diff options
| author | priyanka | 2015-06-24 15:03:17 +0530 |
|---|---|---|
| committer | priyanka | 2015-06-24 15:03:17 +0530 |
| commit | b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b (patch) | |
| tree | ab291cffc65280e58ac82470ba63fbcca7805165 /551 | |
| download | Scilab-TBC-Uploads-b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b.tar.gz Scilab-TBC-Uploads-b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b.tar.bz2 Scilab-TBC-Uploads-b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b.zip | |
initial commit / add all books
Diffstat (limited to '551')
427 files changed, 12260 insertions, 0 deletions
diff --git a/551/CH10/EX10.1/1.sce b/551/CH10/EX10.1/1.sce new file mode 100755 index 000000000..c965270e4 --- /dev/null +++ b/551/CH10/EX10.1/1.sce @@ -0,0 +1,23 @@ +clc
+t_db=293; //K
+W=0.0095; //kg/kg of dry air
+p_t=1.0132;
+disp("(i) Partial pressure of vapour")
+p_v=p_t*W/(W+0.622);
+disp("p_v=")
+disp(p_v)
+disp("bar")
+
+
+disp("(ii) Relative humidity phi :")
+p_vs=0.0234; //bar; From steam tables corresponding to 20 0C
+phi=p_v/p_vs;
+disp("relative hmidity =")
+disp(phi)
+
+
+disp("(iii) Dew point temperature")
+t_dp=13 + (14-13)/(0.01598 - 0.0150)*(0.01524-0.0150); //From stea table by interpolation
+disp("t_dp=")
+disp(t_dp)
+disp("0C")
\ No newline at end of file diff --git a/551/CH10/EX10.10/10.sce b/551/CH10/EX10.10/10.sce new file mode 100755 index 000000000..718b58e42 --- /dev/null +++ b/551/CH10/EX10.10/10.sce @@ -0,0 +1,21 @@ +clc
+p_s=0.0206; //bar
+p_t=1; //bar
+p_s1=0.03782; //bar
+W_2s=0.622*p_s/(p_t-p_s);
+
+cp=1.005;
+t_db2=18; //0C
+t_db1=28; //0C
+
+h_g2=2534.4; //kJ/kg
+h_f2=75.6; //kJ/kg
+h_g1=2552.6; //kJ/kg
+
+W1=(cp*(t_db1-t_db2) + W_2s*(h_g2-h_f2))/(h_g1-h_f2);
+
+p_v1=W1*p_t/(0.622+W1);
+
+RH=p_v1/p_s1; //Relative humidity
+disp("Relative humidity")
+disp(RH)
diff --git a/551/CH10/EX10.11/11.sce b/551/CH10/EX10.11/11.sce new file mode 100755 index 000000000..93a11b397 --- /dev/null +++ b/551/CH10/EX10.11/11.sce @@ -0,0 +1,25 @@ +clc
+t_db1=38; //0C
+t_db2=18; //0C
+phi_1=0.75;
+phi_2=0.85;
+p_t=1; //bar
+cp=1.005;
+
+//At 38 0C
+p_vs=0.0663; //bar
+h_g1=2570.7; //kJ/kg
+p_v=phi_1*p_vs;
+W1=0.622*p_v/(p_t-p_v);
+
+//At 18 0C
+p_vs=0.0206; //bar
+h_g2=2534.4; //kJ/kg
+h_f2=75.6; //kJ/kg
+p_v=phi_2*p_vs;
+W2=0.622*p_v/(p_t-p_v);
+
+q=(W2*h_g2 - W1*h_g1) + cp*(t_db2-t_db1) + (W1-W2)*h_f2;
+disp("Heat transfer rate=")
+disp(q)
+disp("kJ/kg of dry air")
\ No newline at end of file diff --git a/551/CH10/EX10.12/12.sce b/551/CH10/EX10.12/12.sce new file mode 100755 index 000000000..a4f81a497 --- /dev/null +++ b/551/CH10/EX10.12/12.sce @@ -0,0 +1,31 @@ +clc
+
+//At 38 0C
+p_vs=0.0663; //bar
+h_g1=2570.7; //kJ/kg
+phi=0.25;
+p_t=1.0132;
+p_v=phi*p_vs;
+cp=1.005;
+
+//At 18 0C
+h_g2=2534.4; //kJ/kg
+p_vs=0.0206; //bar
+W1=0.622*p_v/(p_t-p_v);
+
+t_db1=38; //0C
+t_db2=18; //0C
+
+W2=(cp*(t_db1-t_db2) + W1*h_g1)/h_g2;
+
+//amount of water added =amt
+amt=W2-W1;
+disp("amt=")
+disp(amt)
+disp("kg/kg of dry air")
+
+p_v2=amt*p_t/(0.622+amt);
+
+RH=p_v2/p_vs;
+disp("Final relative humidity")
+disp(RH)
diff --git a/551/CH10/EX10.13/13.sce b/551/CH10/EX10.13/13.sce new file mode 100755 index 000000000..6af5efa36 --- /dev/null +++ b/551/CH10/EX10.13/13.sce @@ -0,0 +1,43 @@ +clc
+
+disp("(i) Mass of spray water required")
+
+//At 22 0c
+p_vs=0.0264; //bar
+phi_3=0.55;
+p_t=1.0132; //bar
+
+p_v3=phi_3*p_vs;
+W3=0.622*p_v3/(p_t-p_v3);
+
+//At 3 0C
+p_vs1=0.0076; //bar
+p_v1=p_vs1;
+
+W1=0.622*p_v1/(p_t-p_v1);
+
+R=287;
+T_3=295; //K
+
+v=R*T_3/(p_t-p_v3)/10^5;
+
+m=(W3-W1)/v;
+disp(" Mass of spray water required=")
+disp(m)
+disp("kg moisture/m^3")
+
+
+disp("(ii) Temperature to which the air must be heated")
+t_dp=12.5; //0C
+cp=1.005;
+t_db3=22; //0C
+h_g3=2524; //kJ/kg
+h_vapour3=h_g3 + 1.88*(t_db3 - t_dp);
+W2=0.0047;
+h_g2=2524; //kJ/kg
+h4=41.87;
+
+t_db2=(cp*t_db3 + W3*h_vapour3 -W2*h_g2 + 1.88*W2*t_dp - (W3-W2)*h4)/(cp-W2*1.88);
+disp("t_db2=")
+disp(t_db2)
+disp("0C")
\ No newline at end of file diff --git a/551/CH10/EX10.14/14.sce b/551/CH10/EX10.14/14.sce new file mode 100755 index 000000000..d8807d61e --- /dev/null +++ b/551/CH10/EX10.14/14.sce @@ -0,0 +1,52 @@ +clc
+
+disp("(i) Make-up water required")
+p_vs=0.0206; //bar
+phi=0.6;
+p_t=1.013; //bar
+
+p_v1=phi*p_vs;
+p_a1=p_t-p_v1;
+V=9; //m^3
+R=287;
+T=291; //K
+
+m_a=p_a1*10^5*V/R/T;
+
+m_v1=0.0828; //kg/s
+
+//At exit at 26 0C
+p_vs=0.0336; //bar
+phi=1;
+p_v=p_vs;
+W2=0.622*p_v/(p_t-p_v);
+m_v2=W2*m_a;
+
+m=m_v2-m_v1;
+disp("Make-up water required=")
+disp(m)
+disp("kg/s")
+
+
+disp("(ii) Final temperature of the water")
+m_w1=5.5; //kg/s
+m_w2=m_w1-m;
+
+Wi=4.75; //kJ/s
+
+h_w1=184.3; //kJ/kg
+h_a1=18.09; //kJ/kg
+h_v1=2534.74; //kJ/kg
+
+h_v2=2549; //kJ/kg
+h_a2=26.13; //kJ/kg
+
+h_w2=(Wi + m_w1*h_w1 + m_a*h_a1 + m_v1*h_v1 - m_a*h_a2 - m_v2*h_v2)/m_w2;
+
+//By interpolation, h_w2 corresponds to t
+t=26.7; //0C
+disp("final temperature of water=")
+disp(t)
+disp("0C")
+
+
diff --git a/551/CH10/EX10.15/15.sce b/551/CH10/EX10.15/15.sce new file mode 100755 index 000000000..43f66b378 --- /dev/null +++ b/551/CH10/EX10.15/15.sce @@ -0,0 +1,25 @@ +clc
+
+m_water=60000; //kg/s
+c=4.186;
+t1=30; //0C
+t2=35; //0C
+Q=m_water*c*(t2-t1);
+
+h1=76.5; //kJ/kg
+W1=0.016; //kg/kg of air
+h2=92.5; //kJ/kg
+W2=0.0246; //kg/kg of air
+
+m_air=Q/(h2-h1);
+
+A=m_air/10; //Quantity of air handled per fan
+disp("Quantity of air handled per fan=")
+disp(A)
+disp("kg/h")
+
+
+B=m_air*(W2-W1);
+disp("Quantity of make up water=")
+disp(B)
+disp("kg/h")
\ No newline at end of file diff --git a/551/CH10/EX10.17/17.sce b/551/CH10/EX10.17/17.sce new file mode 100755 index 000000000..6c8049f57 --- /dev/null +++ b/551/CH10/EX10.17/17.sce @@ -0,0 +1,20 @@ +clc
+h1=35.4; //kJ/kg
+h2=45.2; //kJ/kg
+v_s1=0.8267; //m^3/kg
+m_a=241.9;
+
+disp("(i) R.H. of heated air =")
+RH=41; // From chart
+disp(RH)
+disp("%")
+
+disp("(ii) WBT of heated air =")
+WBT=16.1; //0C
+disp(WBT)
+disp("ºC")
+
+disp("(iii) Heat added to air per minute =")
+Q=m_a*(h2-h1);
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH10/EX10.18/18.sce b/551/CH10/EX10.18/18.sce new file mode 100755 index 000000000..fe7fcf3e6 --- /dev/null +++ b/551/CH10/EX10.18/18.sce @@ -0,0 +1,29 @@ +clc
+h1=29.3; //kJ/kg
+h2=42.3; //kJ/kg
+h3=h2;
+t_db2=24.5; //0C
+t_db1=12; //0C
+v_s1=0.817; //m^3/kg
+amt=0.30; //Amount of air circulation m^3/min/person
+capacity=60; //Seating capacity of office
+BF=0.4; //By-pass factor
+W3=8.6;
+W1=6.8;
+
+m_a=amt*capacity/v_s1;
+
+disp("(i) Heating capacity of the heating coil =")
+Q=m_a*(h2-h1)/60;
+disp(Q)
+disp("kW")
+
+t_db4=(t_db2-BF*t_db1)/(1-BF);
+disp("Coil surface temperature =")
+disp(t_db4)
+disp("ºC")
+
+disp("(ii) The capacity of the humidifier =")
+c=m_a*(W3-W1)/1000*60;
+disp(c)
+disp("kg/h")
\ No newline at end of file diff --git a/551/CH10/EX10.19/19.sce b/551/CH10/EX10.19/19.sce new file mode 100755 index 000000000..58b848795 --- /dev/null +++ b/551/CH10/EX10.19/19.sce @@ -0,0 +1,37 @@ +clc +h1=82.5; //kJ/kg +h2=47.5; //kJ/kg +h3=55.7; //kJ/kg +h5=36.6; //kJ/kg +W1=19.6; //gm/kg +W3=11.8; //gm/kg +t_db2=17.6; //0C +t_db3=25; //0C +v_s1=0.892; //m^3/kg +amt=250; //m^3/min + +m_a=amt/v_s1; +disp("(i) The capacity of the cooling coil =") +capacity=m_a*(h1-h2)*60/14000; +disp(capacity) +disp("TR") + +BF=(h2-h5)/(h1-h5); +disp("by-pass factor of the cooling coil =") +disp(BF) + +disp("(ii) The heating capacity of the heating coil =") +Q=m_a*(h3-h2)/60; +disp(Q) +disp("kW") + +BF=0.3; +t_db6=(t_db3-BF*t_db2)/(1-BF); +disp("surface temperature of heating coil =") +disp(t_db6) +disp("ºC") + +disp("(iii) The mass of water vapour removed per hour =") +m=m_a*(W1-W3)*60/1000; +disp(m) +disp("kg/h")
\ No newline at end of file diff --git a/551/CH10/EX10.2/2.sce b/551/CH10/EX10.2/2.sce new file mode 100755 index 000000000..c66595aa3 --- /dev/null +++ b/551/CH10/EX10.2/2.sce @@ -0,0 +1,18 @@ +clc
+t_db=290; //K
+phi=0.6; //relative humidity
+p_t=1.01325; //bar
+p_vs=0.0194; //bar
+
+p_v=phi*p_vs;
+
+W=0.622*p_v/(p_t - p_v);
+disp("Specific Humidity=")
+disp(W)
+disp("kg/kg of dry air")
+
+
+t_dp=9 + (10-9)*(0.01164-0.01150)/(0.01230 - 0.01150); //By interpolation from steam tables
+disp("dew point temperature =")
+disp(t_dp)
+ disp("0C")
\ No newline at end of file diff --git a/551/CH10/EX10.3/3.sce b/551/CH10/EX10.3/3.sce new file mode 100755 index 000000000..a9ce8e412 --- /dev/null +++ b/551/CH10/EX10.3/3.sce @@ -0,0 +1,26 @@ +clc
+phi=0.55;
+p_vs=0.0425; //bar
+p_t=1.0132; //bar
+
+p_v=phi*p_vs;
+W=0.622*p_v/(p_t-p_v);
+
+//Specific humidity after removing o.oo4 kg of water vapour
+Wnew=W-0.004;
+p_v=p_t*Wnew/(Wnew+0.622);
+p_vs=0.0234; //bar
+
+disp("(i) Relative humidity")
+phi=p_v/p_vs;
+disp("phi=")
+disp(phi)
+
+
+disp("(ii) Dew point temperature")
+
+disp("Corresponding to 0.0171 bar, from steam tables")
+t_dp=15; //0C
+disp("t_dp=")
+disp(t_dp)
+disp("0C")
\ No newline at end of file diff --git a/551/CH10/EX10.4/4.sce b/551/CH10/EX10.4/4.sce new file mode 100755 index 000000000..1b068dbe5 --- /dev/null +++ b/551/CH10/EX10.4/4.sce @@ -0,0 +1,53 @@ +clc
+t_db=35; //0C
+t_wb=25; //0C
+p_t=1.0132; //bar
+
+//Corresponding to 25 0C in steam tables
+p_vs_wb=0.0317; //bar
+
+p_v=p_vs_wb - (p_t - p_vs_wb)*(t_db - t_wb)/(1527.4 - 1.3*t_wb);
+
+
+disp("(i) Specific humidity")
+W=0.622*p_v/(p_t-p_v);
+disp("W=")
+disp(W)
+disp("kg/kg of dry air")
+
+disp("(ii) Relative humidity")
+
+//Corresponding to 35 0C, from steam tables
+p_vs=0.0563;
+
+phi=p_v/p_vs;
+disp("phi")
+disp(phi)
+
+
+disp("(iii) Vapour density")
+R_v=8314.3/18;
+T_v=308; //K
+
+rho_v=p_v*10^5/(R_v*T_v);
+disp("rho_v=")
+disp(rho_v)
+disp("kg/m^3")
+
+
+disp("(iv) Dew point temperature")
+t_dp=21 + (22-21)*(0.0252-0.0249)/(0.0264-0.0249);
+disp("t_dp")
+disp(t_dp)
+disp("0C")
+
+
+disp("(v) Enthalpy of mixture per kg of dry air")
+cp=1.005;
+h_g=2565.3; //kJ/kg; corresponding to 35 0C
+h_vapour=h_g + 1.88*(t_db - t_dp);
+
+h=cp*t_db + W*h_vapour;
+disp("h=")
+disp(h)
+disp("kJ/kg of dry air")
\ No newline at end of file diff --git a/551/CH10/EX10.5/5.sce b/551/CH10/EX10.5/5.sce new file mode 100755 index 000000000..4c727bf42 --- /dev/null +++ b/551/CH10/EX10.5/5.sce @@ -0,0 +1,46 @@ +clc
+
+//For the air at 35 0C DBT and 60% R.H.
+p_vs=0.0563; //bar; Corresponding to 35 0C from stem tables
+
+phi=0.6;
+p_t=1.0132; //bar
+cp=1.005;
+t_db=35; //0C
+h_g=2565.5; //kJ/kg
+m1=1; //kg
+m2=2; //kg
+m=m1+m2;
+
+p_v=phi*p_vs;
+W1=0.622*p_v/(p_t-p_v);
+
+//Corresponding to 0.0388 bar, from steam tables
+t_dp=26+(27-26)*(0.0338-0.0336)/(0.0356-0.0336);
+
+h_vapour=h_g + 1.88*(t_db - t_dp);
+h1=cp*t_db+W1*h_vapour;
+
+//For the air at 20°C DBT and 13°C dew point temperature :
+p_v=0.0150; //bar
+
+W2=0.622*p_v/(p_t-p_v);
+t_db=20; //0C
+t_dp=13;
+h_g=2538.1; //kJ/kg
+h_vapour=h_g + 1.88*(t_db - t_dp);
+
+h2=cp*t_db+W2*h_vapour;
+
+//let enthalpy per kg of moist air be h
+h=((m1*h1/(1+W1)) + (m2*h2/(1+W2)))/m;
+
+//Let Mass of vapour/kg of moist air be M
+M=(m1*W1/(1+W1) + m2*W2/(1+W2))/m;
+
+
+//Let specific humidity be denoted by SH
+SH=M/(1-M);
+disp("Specific humidity =")
+disp(SH)
+disp("kg/kg of dry air")
\ No newline at end of file diff --git a/551/CH10/EX10.6/6.sce b/551/CH10/EX10.6/6.sce new file mode 100755 index 000000000..6c896a4ae --- /dev/null +++ b/551/CH10/EX10.6/6.sce @@ -0,0 +1,43 @@ +clc
+
+//For air at 20 0C and 75% R.H
+p_vs=0.0234; //bar
+phi=0.75;
+p_t=1.0132;
+cp=1.005;
+t_db=20; //0C
+
+
+p_v=phi*p_vs;
+t_dp=15 + (16-15)*(0.01755-0.017)/(0.0182-0.017);
+W=0.622*p_v/(p_t-p_v);
+
+h_g=2538.1; //kJ/kg
+h_vapour=h_g + 1.88*(t_db - t_dp);
+h1=cp*t_db + W*h_vapour;
+
+
+disp("(i) Relative humidity of heated air :")
+
+//For air at 30°C DBT
+p_vs=0.0425; //bar; corresponding to 30 0C
+phi=p_v/p_vs;
+disp("Relative humidity=")
+disp(phi*100)
+disp("%")
+
+
+disp("(ii) Heat added to air per minute")
+h_g=2556.3; //kJkg
+t_db=30;
+h2=cp*t_db+W*h_vapour;
+V=90; //m^3
+R=287;
+T=293; //K
+
+m=(p_t-p_v)*V*10^5/R/T;
+
+Amt=m*(h2-h1);
+disp("Amount of heat added per minute=")
+disp(Amt)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH10/EX10.7/7.sce b/551/CH10/EX10.7/7.sce new file mode 100755 index 000000000..b225b57b0 --- /dev/null +++ b/551/CH10/EX10.7/7.sce @@ -0,0 +1,43 @@ +clc
+
+//For air at 35 0C DBT and 50% RH
+p_vs=0.0563; //bar; At 35 0C, from steam tables
+phi=0.5;
+p_t=1.0132;
+t_db1=35; //0C
+t_dp1=23; //0C
+cp=1.005;
+R=287;
+p_v=phi*p_vs;
+W1=0.622*p_v/(p_t-p_v);
+h_g1=2565.3; //kJ/kg
+
+h_vapour=h_g1 + 1.88*(t_db1 - t_dp1);
+h1=cp*t_db1+W1*h_vapour;
+
+
+disp("(i) R.H. of cooled air")
+p_vs=0.0317;
+phi=p_v/p_vs;
+disp("RH of cooled air=")
+disp(phi*100)
+disp("%")
+
+
+disp("(ii) Heat removed from air")
+h_g2=2547.2; //kJ/kg
+t_db2=25; //0C
+t_dp2=23; //0C
+W2=W1;
+T=308; //K
+V=40; //m^3
+
+h_vapour=h_g2 + 1.88*(t_db2 - t_dp2);
+h2=cp*t_db2+W2*h_vapour;
+m=(p_t-p_v)*10^5*V/R/T;
+
+//Let Heat removed be denoted by H
+H=m*(h1-h2);
+disp("Heat removed =")
+disp(H)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH10/EX10.8/8.sce b/551/CH10/EX10.8/8.sce new file mode 100755 index 000000000..9b5e89330 --- /dev/null +++ b/551/CH10/EX10.8/8.sce @@ -0,0 +1,58 @@ +clc
+
+//For the air at 35°C DBT and 50% R.H.
+p_vs=0.0563; //bar; At 35 0C, from steam tables
+phi=0.5;
+p_v=phi*p_vs;
+p_t=1.0132; //bar
+
+t_dp1=23; //0C
+t_db1=35; //0C
+W1=0.622*p_v/(p_t-p_v);
+h_g1=2565.3; //kJ/kg
+R=287;
+cp=1.005;
+
+h_vapour=h_g1 + 1.88*(t_db1 - t_dp1);
+h1=cp*t_db1+W1*h_vapour;
+
+
+disp("(i) Relative humidity of out coming air and its wet bulb temperature.")
+
+disp("Relative humidity of exit air is 100 per cent.")
+
+t_wb=20; //0C
+disp("Wet bulb temperture=")
+disp(t_wb)
+disp("0C")
+
+p_v=0.0234; //bar
+p_vs=p_v;
+t_db2=20; //0C
+h_g2=2538.1; //kJ/kg
+t_dp2=t_db2;
+
+W2=0.622*p_v/(p_t-p_v);
+h_vapour=h_g2 + 1.88*(t_db2 - t_dp2);
+h2=cp*t_db2+W2*h_vapour;
+
+T=308; //K
+V=120; //m^3
+
+W=W1-W2; //Weight of water vvapour removed per kg of dry air
+h=h1-h2; //Heat removed per kg of dry air
+m=(p_t-p_v)*10^5*V/R/T;
+
+
+disp("(ii) Capacity of the cooling coil in tonnes of refrigeration")
+C=m*(h1-h2)*60/14000;
+disp("Capacity =")
+disp(C)
+disp("TR")
+
+
+disp("(iii) Amount of water removed per hour")
+Amt=m*(W1-W2)*60;
+disp("Amount of water removed per hour=")
+disp(Amt)
+disp("kg/h")
\ No newline at end of file diff --git a/551/CH10/EX10.9/9.sce b/551/CH10/EX10.9/9.sce new file mode 100755 index 000000000..bf23234df --- /dev/null +++ b/551/CH10/EX10.9/9.sce @@ -0,0 +1,42 @@ +clc
+p_vs=0.0563; //bar
+phi=0.2;
+p_v=phi*p_vs;
+p_t=1.0132; //bar
+
+W1=0.622*p_v/(p_t-p_v);
+
+disp("(i) Dew point temperature")
+//
+t_dp=8+(9-8)*(0.01126-0.01072)/(0.01150-0.01072);
+disp("dew point temperature=")
+disp(t_dp)
+disp("0C")
+
+
+disp("(ii) Relative humidity of the exit air :")
+p_vs_wb=0.0170; //bar
+p_vs=0.0234; //bar
+t_db=20; //0C
+t_wb=15; //0C
+
+p_v=p_vs_wb - (p_t-p_vs_wb)*(t_db-t_wb)/(1527.4-1.3*t_wb);
+W2=0.622*p_v/(p_t-p_v);
+
+RH=p_v/p_vs;
+disp("Relative humidity=")
+disp(RH)
+
+p_v=0.01126; //bar
+R=287;
+T=308; //K
+V=150;
+
+m=(p_t-p_v)*V*10^5/R/T;
+
+
+disp("(iii) Amount of water vapour added to the air per minute")
+amt=m*(W2-W1);
+disp("Amount =")
+disp(amt)
+disp("kg/min")
\ No newline at end of file diff --git a/551/CH11/EX11.1/1.sce b/551/CH11/EX11.1/1.sce new file mode 100755 index 000000000..c62992869 --- /dev/null +++ b/551/CH11/EX11.1/1.sce @@ -0,0 +1,28 @@ +clc
+
+%C=0.88; //Fraction of carbon in coal
+%H=0.042; //Fraction of Hydrogen in coal
+w_f=0.848; //gm
+w_fw=0.027; //gm
+w=1950; //gm
+w_e=380; //gm
+dt=3.06; //0C; Observed temperature rise
+tc=0.017; //0C
+dt1=dt+tc; //Corrected temperature rise
+Cal=6700; //J/gm; Calorific value of fuse wire
+
+Q_received=(w+w_e)*4.18*dt1; //Heat received by water
+
+Q_rejected=w_fw*Cal; //Heat given out by fuse wire
+
+Q_produced=Q_received - Q_rejected;
+
+HCV=Q_produced/w_f;
+disp("Higher calorific value=")
+disp(HCV)
+disp("kJ/kg")
+
+LCV=HCV - 2465*9*%H;
+disp("Lower Calorific value=")
+disp(LCV)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH11/EX11.11/11.sce b/551/CH11/EX11.11/11.sce new file mode 100755 index 000000000..a661229f1 --- /dev/null +++ b/551/CH11/EX11.11/11.sce @@ -0,0 +1,41 @@ +clc
+
+C=80;
+
+//Analysis of gas entering the economiser
+CO2_1=8.3;
+CO_1=0;
+O2_1=11.4;
+N2_1=80.3;
+
+//Analysis of gas leaving the economiser
+CO2_2=7.9;
+CO_2=0;
+O2_2=11.5;
+N2_2=80.6;
+
+A1=N2_1*C/33/(CO2_1 + CO_1); //Air supplied on the basis of conditions at entry to the economiser
+
+A2=N2_2*C/33/(CO2_2 + CO_2); //Air applied on the basis of conditions at exit
+
+leakage=A2-A1; //Air leakage
+disp("Air leakege =")
+disp(leakage)
+disp("kg of air per kg of fuel")
+
+W_fuel=0.85; //kg; Weight of fuel passing up the chimney
+
+c=1.05;
+T2=410;
+T1=0;
+
+W=A1+W_fuel; //Total weight of products
+Q1=W*c*(T2-T1); //Heat in flue gases per kg of coal
+Q2=leakage*1.005*(20-0); //Heat in leakage air
+
+t=(Q1+Q2)/(1.005*leakage + W*1.05);
+
+dT=T2-t;
+disp("Fall in temperature as a result of the air leakage into the economiser")
+disp(dT)
+disp("°C")
diff --git a/551/CH11/EX11.12/12.sce b/551/CH11/EX11.12/12.sce new file mode 100755 index 000000000..0bab44308 --- /dev/null +++ b/551/CH11/EX11.12/12.sce @@ -0,0 +1,23 @@ +clc
+
+w_O2=3*32/46*100/23; //For complete combustion of 1 kg of C2H6O, oxygen required
+
+ratio=w_O2;
+disp("A:F ratio=")
+disp(ratio)
+
+w1=88; //kg
+w2=54; //kg
+
+w=w1+w2; //kg
+W=46; //kg
+
+w_CO2=w1/W*100;
+disp("CO2 produced by fuel")
+disp(w_CO2)
+disp("%")
+
+w_H2O=w2/W*100;
+disp("H2O produced by fuel")
+disp(w_H2O)
+disp("%")
diff --git a/551/CH11/EX11.13/13.sce b/551/CH11/EX11.13/13.sce new file mode 100755 index 000000000..5b34a3206 --- /dev/null +++ b/551/CH11/EX11.13/13.sce @@ -0,0 +1,15 @@ +clc +// C2H2+xO2---->aCO2+bH2O +// 2C=aC; a=2 +// 2H=2bH; b=1 +// x=2.5 + +// C2H2+2.5O2+2.5*(79/21)N2 --> 2CO2+H2O+2.5*(79/21)N2 + +// 26 kg C2H2 + 80 kg O2 + 263.3 N2 → 88 kg CO2 + 18 kg H2O + 263.3 kg N2 +// 1 kg C2H2 + 3.076 kg O2 + 10.12 kg N2 → 3.38 kg CO2 + 0.69 kg H2O + 10.12 kg N2 + +Amount= 3.076 + 10.12; +disp("Hence amount of theoretical air required for combustion of 1 kg acetylene =") +disp(Amount) +disp("kg")
\ No newline at end of file diff --git a/551/CH11/EX11.14/14.sce b/551/CH11/EX11.14/14.sce new file mode 100755 index 000000000..a3915d8f3 --- /dev/null +++ b/551/CH11/EX11.14/14.sce @@ -0,0 +1,34 @@ +clc
+// C2H2+2.5O2+2.5*(79/21)N2 --> 2CO2+H2O+2.5*(79/21)N2
+
+//26 kg C2H2 + 160 kg O2 + 526.6 kg N2 → 88 kg CO2 + 18 kg H2O + 526.6 kg N2 + 80 kg O2
+
+//1 kg C2H2 + 6.15 kg O2 + 20.25 kg N2 → 3.38 kg CO2 + 0.69 kg H2O + 20.25 kg N2 + 3.07 kg O2
+
+m_CO2=3.38; //kg
+m_H2O=0.69; //kg
+m_O2=3.07; //kg
+m_N2=20.25; //kg
+m_total=m_CO2+m_H2O+m_O2+m_N2;
+
+CO2=m_CO2/m_total*100;
+H2O=m_H2O/m_total*100;
+O2=m_O2/m_total*100;
+N2=m_N2/m_total*100;
+
+disp("Hence the gravimetric analysis of the complete combustion is :")
+disp("CO2=")
+disp(CO2)
+disp("%")
+
+disp("H2O=")
+disp(H2O)
+disp("%")
+
+disp("O2=")
+disp(O2)
+disp("%")
+
+disp("N2=")
+disp(N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.15/15.sce b/551/CH11/EX11.15/15.sce new file mode 100755 index 000000000..c0b93cc09 --- /dev/null +++ b/551/CH11/EX11.15/15.sce @@ -0,0 +1,7 @@ +clc
+AF_mole=(12.5+12.5*(79/21))/1;
+AF_mass=AF_mole*28.97/(8*12+1*18);
+
+disp("Air fuel ratio =")
+disp(AF_mass)
+disp("kg air/kg fuel")
\ No newline at end of file diff --git a/551/CH11/EX11.16/16.sce b/551/CH11/EX11.16/16.sce new file mode 100755 index 000000000..7ac5bf175 --- /dev/null +++ b/551/CH11/EX11.16/16.sce @@ -0,0 +1,24 @@ +clc
+// C8H18+12.5*O2+12.5*(79/21)N2 --> 8CO2+9H2O+12.5*(79/21)*N2
+
+// C8H18 + (2) (12.5) O2 + (2) (12.5)*(79/21)N2-->8CO2 + 9H2O + (1) (12.5) O2 + (2) (12.5)*(79/21)*N2
+
+m_fuel=1*(8*12+1*18);
+m_air=2*12.5*(1+79/21)*28.97;
+
+disp("(i) Air-fuel ratio =")
+AF=m_air/m_fuel;
+disp(AF)
+
+disp("(ii) Dew point of the products")
+n=8+9+12.5+2*12.5*(79/21);
+
+x=9/n;
+p=100*x;
+
+//Hence
+t_dp=39.7; //0C
+
+disp("t_dp=")
+disp(t_dp)
+disp("°C")
\ No newline at end of file diff --git a/551/CH11/EX11.17/17.sce b/551/CH11/EX11.17/17.sce new file mode 100755 index 000000000..fbdea5958 --- /dev/null +++ b/551/CH11/EX11.17/17.sce @@ -0,0 +1,29 @@ +clc
+// C2H6 + 3.5O2 → 2CO2 + 3H2O
+// C2H6 + (0.9)*(3.5) O2 + (0.9)*(3.5)*(79/21)N2→a CO2 + b CO + 3H2O + (0.9)*(3.5)*(79/21)*N2
+
+// a+b=2
+// 2*a+b+3=0.9*3.5*2
+// a=1.3
+// b=0.7
+// C2H6 + (0.9)*(3.5) O2 + (0.9)*(3.5)*(79/21)*N2→ 1.3CO2 + 0.7CO + 3H2O + (0.9)*(3.5)*(79/21)N2
+
+n=1.3+0.7+0.9*3.5*(79/21);
+
+CO2=1.3/n*100;
+CO=0.7/n*100;
+N2=11.85/n*100;
+
+disp("Volumetric analysis of dry products of combustion is as follows ")
+
+disp("CO2 =")
+disp(CO2)
+disp("%")
+
+disp("CO =")
+disp(CO)
+disp("%")
+
+disp("N2 =")
+disp(N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.18/18.sce b/551/CH11/EX11.18/18.sce new file mode 100755 index 000000000..014b9ff04 --- /dev/null +++ b/551/CH11/EX11.18/18.sce @@ -0,0 +1,36 @@ +clc
+disp("(i) Combustion equation")
+
+// x CH4 + y O2 + z N2 → 10.0 CO2 + 0.53 CO + 2.37 O2 + a H2O + 87.1 N2
+
+z=87.1;
+y=z*(79/21);
+x=10+0.53;
+a=2*x;
+
+//10.53 CH4 + 23.16 O2 + 87.1 N2 → 10.0 CO2 + 0.53 CO + 2.37 O2 + 21.06 H2O + 87.1 N2
+
+disp("CH4 + 2.2 O2 + 8.27 N2 → 0.95 CO2 + 0.05 CO + 2H2O + 0.225 O2 + 8.27 N2")
+
+disp("(ii) Air-fuel ratio ")
+
+AF_mole=2.2+8.27;
+disp("air-fuel ratio on a mole basis =")
+disp(AF_mole)
+disp("moles air/mole fuel")
+
+AF_mass=AF_mole*28.97/(12+1*4);
+disp("air-fuel ratio on a mass basis =")
+disp(AF_mass)
+disp("air/kg fuel")
+
+// CH4 + 2O2 + 2*(79/21)N2 → CO2 + 2H2O + (2)*(79/21)N2
+AF_theor=(2+2*(79/21))*28.97/(12+1*4);
+disp("theoretical air-fuel ratio =")
+disp(AF_theor)
+disp("kg air/kg fuel")
+
+disp("(iii) Percent theoretical air =")
+%theo=AF_mass/AF_theor*100;
+disp(%theo)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.19/19.sce b/551/CH11/EX11.19/19.sce new file mode 100755 index 000000000..59b39f195 --- /dev/null +++ b/551/CH11/EX11.19/19.sce @@ -0,0 +1,33 @@ +clc
+disp("(i) The stoichiometric A/F ratio")
+
+// 1 kg of coal contains 0.82 kg C and 0.10 kg H2.
+// Let the oxygen required for complete combustion = x moles
+// the nitrogen supplied with the oxygen = x*79/21=3.76*x
+// 0.82/12*C+0.10/2*H2 + x CO2 + 3.76x N2 → a CO2 + b H2O + 3.76 x N2
+a=0.82/12; // Carbon balance
+b=0.10/2; //Hydrogen balance
+x=(2*a+b)/2; // Oxygen balance
+
+Stoichiometric_AF_ratio=2.976/0.233;
+disp("Stoichiometric AF ratio =")
+disp(Stoichiometric_AF_ratio)
+
+n=a+b+3.76*x;
+
+CO2=0.068/n*100;
+H2=0.05/n*100;
+N2=3.76*0.093/n*100;
+
+disp("the analysis of the products is")
+disp("CO2 =")
+disp(CO2)
+disp("%")
+
+disp("H2 =")
+disp(H2)
+disp("%")
+
+disp("N2 =")
+disp(N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.2/2.sce b/551/CH11/EX11.2/2.sce new file mode 100755 index 000000000..a1be2da55 --- /dev/null +++ b/551/CH11/EX11.2/2.sce @@ -0,0 +1,26 @@ +clc
+p1=75.882; //cm of Hg
+T1=286; //K
+V1=0.08; //m^3
+p2=76; //cm of Hg
+T2=288; //K
+
+V2=p1*V1*T2/p2/T1;
+
+m=28; //kg
+c=4.18;
+t2=23.5; //0C
+t1=10; //0C
+
+Q_received=m*c*(t2-t1);
+
+HCV=Q_received/V2;
+disp("Higher calorific value =")
+disp(HCV)
+disp("kJ/m^3")
+
+amt=0.06/0.08; //Amount of vapour formed per m^3 of gas burnt
+LCV=HCV-2465*amt;
+disp("Lower calorific value =")
+disp(LCV)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH11/EX11.20/20.sce b/551/CH11/EX11.20/20.sce new file mode 100755 index 000000000..f61a72615 --- /dev/null +++ b/551/CH11/EX11.20/20.sce @@ -0,0 +1,76 @@ +clc
+
+// C + O2 → CO2
+// 2H2 + O2 → 2H2O
+// S + O2 → SO2
+
+O2_req=2.636; //kg
+
+AF=O2_req/0.233;
+disp("The stoichiometric A/F ratio =")
+disp(AF)
+
+disp("(i) Actual A/F ratio =")
+AF_act=AF+0.3*AF;
+disp(AF_act)
+
+disp("(ii) Wet and dry analyses of products of combustion by volume")
+
+// As per actual A/F ratio, N2 supplied = 0.767 * 14.7 = 11.27 kg
+// Also O2 supplied = 0.233 * 14.7 = 3.42 kg
+
+// In the products then, we have
+// N2 = 11.27 + 0.01 = 11.28 kg
+// excess O2 = 3.42 – 2.636 = 0.78 kg
+
+n_wet=0.5208;
+n_dry=0.5008;
+
+disp("Analysis of wet products is as follows :")
+
+disp("CO2 =")
+CO2=0.0734/n_wet*100;
+disp(CO2)
+disp("%")
+
+disp("H2O =")
+H2O=0.0200/n_wet*100;
+disp(H2O)
+disp("%")
+
+disp("SO2 =")
+SO2=0.0002/n_wet*100;
+disp(SO2)
+disp("%")
+
+disp("O2 =")
+O2=0.0244/n_wet*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=0.4028/n_wet*100;
+disp(N2)
+disp("%")
+
+disp("Analysis of dry products is as follows :")
+
+disp("CO2 =")
+CO2=0.0734/n_dry*100;
+disp(CO2)
+disp("%")
+
+disp("SO2 =")
+SO2=0.0002/n_dry*100;
+disp(SO2)
+disp("%")
+
+disp("O2 =")
+O2=0.0244/n_dry*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=0.4028/n_dry*100;
+disp(N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.21/21.sce b/551/CH11/EX11.21/21.sce new file mode 100755 index 000000000..d83ed8f02 --- /dev/null +++ b/551/CH11/EX11.21/21.sce @@ -0,0 +1,59 @@ +clc
+
+// 2H2 + O2 → 2H2O
+// 2CO + O2 → 2CO2
+// CH4 + 2O2 → CO2 + 2H2O
+// C4H8 + 6O2 → 4CO2 + 4H2O
+
+n_O2=0.853; //total moles of O2
+
+disp("(i) Stoichiometric A/F ratio =")
+AF=n_O2/0.21;
+disp(AF)
+
+disp("(ii) Wet and dry analyses of the products of combustion if the actual mixture is 30% weak :")
+AF_act=AF+0.3*AF;
+n_N2=0.79*AF_act;
+O2_excess=0.21*AF_act-n_O2;
+
+n_wet=5.899;
+n_dry=4.915;
+
+disp("Analysis by volume of wet products is as follows :")
+
+disp("CO2 =")
+CO2=0.490/n_wet*100;
+disp(CO2)
+disp("%")
+
+disp("H2O =")
+H2O=0.984/n_wet*100;
+disp(H2O)
+disp("%")
+
+disp("O2 =")
+O2=O2_excess/n_wet*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=n_N2/n_wet*100;
+disp(N2)
+disp("%")
+
+disp("Analysis by volume of dry products is as follows :")
+
+disp("CO2 =")
+CO2=0.490/n_dry*100;
+disp(CO2)
+disp("%")
+
+disp("O2 =")
+O2=O2_excess/n_dry*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=n_N2/n_dry*100;
+disp(N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.22/22.sce b/551/CH11/EX11.22/22.sce new file mode 100755 index 000000000..932968eab --- /dev/null +++ b/551/CH11/EX11.22/22.sce @@ -0,0 +1,65 @@ +clc
+
+// C2H6O + 3O2 + 3*79/21 N2 → 2CO2 + 3H2O + 3*79/21 N2
+
+O2_req=3*32/46;
+
+AF=O2_req/0.233;
+disp("Stoichiometric A/F ratio =")
+disp(AF)
+
+mix=0.8; //mixture strength
+
+AF_actual=AF/mix;
+disp("Actual A/F ratio =")
+disp(AF_actual)
+
+// C2H6O + 1.25*(3 O2 + 3*79/21 N2) → 2CO2 + 3H2O + 0.25*3O2 + 1.25*3*79/21 N2
+
+n=2+3+0.75+14.1;
+
+disp("Hence wet analysis is")
+
+disp("CO2 =")
+CO2=2/n*100;
+disp(CO2)
+disp("%")
+
+disp("H2O =")
+H2O=3/n*100;
+disp(H2O)
+disp("%")
+
+disp("O2 =")
+O2=0.75/n*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=14.1/n*100;
+disp(N2)
+disp("%")
+
+nd=2+0.75+14.1; //total dry moles
+
+disp("Hence dry analysis is : ")
+
+disp("CO2 =")
+CO2=2/nd*100;
+disp(CO2)
+disp("%")
+
+disp("O2 =")
+O2=0.75/nd*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=14.1/nd*100;
+disp(N2)
+disp("%")
+
+mix=1.3;
+AF_act=AF/mix;
+disp("Actual A/F ratio =")
+disp(AF_act)
\ No newline at end of file diff --git a/551/CH11/EX11.23/23.sce b/551/CH11/EX11.23/23.sce new file mode 100755 index 000000000..b5947cf35 --- /dev/null +++ b/551/CH11/EX11.23/23.sce @@ -0,0 +1,30 @@ +clc
+// C2H6O + 3O2 + 3*79/21 N2 → 2CO2 + 3H2O + 3*79/21 N2
+R0=8.314*10^3; //kJ/kg K
+m=46; //kg
+
+disp("(i) Volume of reactants per kg of fuel ")
+
+n=1+3+3*79/21;
+T=323; //K
+p=1.013*10^5; //Pa
+
+V=n*R0*T/p;
+
+disp("Vr=")
+Vr=V/m;
+disp(Vr)
+disp("m^3")
+
+disp("(ii) Volume of products per kg of fuel")
+
+n=2+3+3*79/21;
+T=403; //K
+p=1*10^5; //Pa
+
+V=n*R0*T/p;
+
+Vp=V/m;
+disp("Vp=")
+disp(Vp)
+disp("m^3")
\ No newline at end of file diff --git a/551/CH11/EX11.24/24.sce b/551/CH11/EX11.24/24.sce new file mode 100755 index 000000000..e4dbc8e34 --- /dev/null +++ b/551/CH11/EX11.24/24.sce @@ -0,0 +1,26 @@ +clc
+
+// 0.506H2 + 0.1CO + 0.26CH4 + 0.04C4H8 + 0.004O2 + 0.03CO2 + 0.06N2 + 0.21 × 7O2 + 0.79 × 7N2 → a CO2 + b H2O + c O2 + d N2
+
+a=0.1*0.26+4*0.04+0.03;
+b=(2*0.506+4*0.26+8*0.04)/2;
+c=(0.1+2*0.004+2*0.03+0.21*7*2-2*a-b)/2;
+d=(2*0.06+2*0.79*7)/2;
+
+n=0.55+0.411+5.59;
+
+disp("analysis by volume is")
+disp("CO2=")
+CO2=0.55/n*100;
+disp(CO2)
+disp("%")
+
+disp("O2=")
+O2=0.411/n*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=5.59/n*100;
+disp(N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.25/25.sce b/551/CH11/EX11.25/25.sce new file mode 100755 index 000000000..5234e1e93 --- /dev/null +++ b/551/CH11/EX11.25/25.sce @@ -0,0 +1,20 @@ +clc
+// C_aH_bO_cN_dS_e
+
+a=60/12;
+b=20;
+c=5/16;
+d=10/14;
+e=5/32;
+
+// C_5 H_20 O_0.3125 N_0.7143 S_0.1562 + x O2 + x*(79/21)N2 → p CO2 + q H2O + r SO2 + s N2
+p=5;
+q=20/2;
+r=0.1562;
+x=(2*p+q+2*r-0.3125)/2;
+s=(0.7143+2*x*79/21)/2;
+
+air=(9.92*32+x*79/21*28)/100;
+disp("Stoichiometric air required =")
+disp(air)
+disp("kg/kg of fuel")
\ No newline at end of file diff --git a/551/CH11/EX11.26/26.sce b/551/CH11/EX11.26/26.sce new file mode 100755 index 000000000..5433e3d82 --- /dev/null +++ b/551/CH11/EX11.26/26.sce @@ -0,0 +1,42 @@ +clc
+
+disp("(i) Stoichiometric air fuel ratio ")
+// C_aH_bO_cN_d
+
+a=84/12;
+b=10;
+c=3.5/16;
+d=1.5/14;
+
+// C7 H10 O0.218 N0.107 + x O2 + x*(79/21)N2 → p CO2 + q H2O + r N2
+
+p=7;
+q=10/2;
+x=(2*p+q-c)/2;
+r=(d+2*x*(79/21))/2;
+
+AF=(x*32+x*79/21*28)/100;
+disp("Stoichiometric A/F ratio =")
+disp(AF)
+
+disp("(ii) Percentage composition of dry flue gases by volume with 20 per cent excess air :")
+
+// C7H10O0.218N0.107 + (1.2)(9.39) O2 + (1.2)(9.39)*(79/21)N2 → 7CO2 + 5H2O + (0.2)(9.39) O2 + (1.2)(35.4) N2
+
+n=7+0.2*9.39+1.2*35.4;
+
+disp("Percentage composition of dry flue gases by volume is as follows :")
+disp("CO2 =")
+CO2=7/n*100;
+disp(CO2)
+disp("%")
+
+disp("O2 =")
+O2=1.878/n*100;
+disp(O2)
+disp("%")
+
+disp("N2 =")
+N2=42.48/n*100;
+disp(N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.27/27.sce b/551/CH11/EX11.27/27.sce new file mode 100755 index 000000000..f4fcfff7e --- /dev/null +++ b/551/CH11/EX11.27/27.sce @@ -0,0 +1,21 @@ +clc
+// a C + b H + c O2 + (79/21)*c N2 = 8CO2 + 0.5CO + 6.3O2 + x H2O + 85.2N2
+
+a=8+0.5;
+c=85.2/(79/21);
+x=2*(c-8-0.5/2-6.3);
+b=2*x;
+
+disp("(i) Air-fuel ratio =")
+AF=(c*32+(79/21)*c*28)/(a*12+b*1);
+disp(AF)
+disp("kg of air/kg of fuel")
+
+disp("(ii) Per cent theoretical air required for combustion ")
+mf_C=12*a/(12*a+b);
+mf_H2=b*1/(12*a+b);
+air=mf_C*8/3*100/23.3 + mf_H2*8*100/23.3; //air required for complete combustion
+percent=AF/air*100;
+disp("Per cent theoretical air required for combustion =")
+disp(percent)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.28/28.sce b/551/CH11/EX11.28/28.sce new file mode 100755 index 000000000..6936cf1a6 --- /dev/null +++ b/551/CH11/EX11.28/28.sce @@ -0,0 +1,22 @@ +clc
+disp("(i) By a carbon balance")
+
+// a C8H18 + 78.1N2 + 78.1*(21/79)O2 → 8.9CO2 + 8.2CO + 4.3H2 + 0.5CH4 + 78.1N2 + x H2O
+a=(8.9+8.2+0.5)/8;
+
+AF1=(78.1*28+78.1*21/79*32)/a/(8*12+1*18);
+disp("Air fuel ratio =")
+disp(AF1)
+
+
+disp("(ii) By a hydrogen-oxygen balance ")
+
+// a C8H18 + b O2 + b*(79/21)N2 → 8.9CO2 + 8.2CO + 4.3H2 + 0.5CH4 + b*(79/21)N2 + x*H2O
+
+a=(8.9+8.2+0.5)/8;
+x=(18*a-4.3*2-4*0.5)/2;
+b=(8.9*2+8.2+x)/2;
+
+AF2=(b*32+b*(79/21)*28)/a/(8*12+1*18);
+disp("Air fuel ratio =")
+disp(AF2)
\ No newline at end of file diff --git a/551/CH11/EX11.29/29.sce b/551/CH11/EX11.29/29.sce new file mode 100755 index 000000000..0e25824b5 --- /dev/null +++ b/551/CH11/EX11.29/29.sce @@ -0,0 +1,12 @@ +clc
+// X(0.88/12 C + 0.12/2 H2) + Y O2 + 79/21*Y N2 → 0.12CO2 + a O2 + (0.88 – a) N2 + b H2O
+
+X=0.12/(0.88/12);
+b=0.06*X;
+a=0.0513;
+Y=0.2203;
+Air_supplied=0.2203*32/0.233;
+
+AF=Air_supplied/X;
+disp("A/F ratio =")
+disp(AF)
\ No newline at end of file diff --git a/551/CH11/EX11.3/3.sce b/551/CH11/EX11.3/3.sce new file mode 100755 index 000000000..e251cfca0 --- /dev/null +++ b/551/CH11/EX11.3/3.sce @@ -0,0 +1,12 @@ +clc
+C=0.85; //Weight of Carbon present
+H2=0.06; //Weight of Hydrogen present
+O2=0.06; //Weight of Oxygen present
+
+w_required=C*8/3 + H2*8; //Weight of O2 required
+w_needed=w_required-O2; //Weight of O2 to be supplied
+
+w_air=w_needed*100/23;
+disp("Weight of air needed=")
+disp(w_air)
+disp("kg")
\ No newline at end of file diff --git a/551/CH11/EX11.30/30.sce b/551/CH11/EX11.30/30.sce new file mode 100755 index 000000000..7dce1cf71 --- /dev/null +++ b/551/CH11/EX11.30/30.sce @@ -0,0 +1,11 @@ +clc
+// X*(x/12 C + y/2 H2) + Y O2 + 79/21*Y/N2 → 0.15CO2 + 0.03CO + 0.03CH4 + 0.01H2 + 0.02O2 + a H2O + 0.76N2
+
+Y=0.76/(79/21);
+a=2*(Y-0.15-0.03/2-0.02);
+Xx=12*(0.15+0.03+0.03);
+Xy=2*(2*0.03+0.01+a);
+ratio=Xx/Xy;
+
+disp("Ratio of C to H2 in fuel =")
+disp(ratio)
\ No newline at end of file diff --git a/551/CH11/EX11.31/31.sce b/551/CH11/EX11.31/31.sce new file mode 100755 index 000000000..f04ab401f --- /dev/null +++ b/551/CH11/EX11.31/31.sce @@ -0,0 +1,9 @@ +clc
+h_fg0=2441.8; //kJ/kg
+m=3*18;
+dH0_liq=-3301000; //kJ/mole
+
+dH0_vap=dH0_liq+m*h_fg0;
+disp("dH0_vapour =")
+disp(dH0_vap)
+disp("kJ/mole")
\ No newline at end of file diff --git a/551/CH11/EX11.32/32.sce b/551/CH11/EX11.32/32.sce new file mode 100755 index 000000000..65a8fc3b0 --- /dev/null +++ b/551/CH11/EX11.32/32.sce @@ -0,0 +1,13 @@ +clc
+
+// C6H6 + 7.5O2 → 6CO2 + 3H2O (vapour)
+dH0=-3169100; //kJ
+n_R=1+7.5;
+n_P=6+3;
+R0=8.314;
+T0=298; //K
+
+dU0=(dH0-(n_P-n_R)*R0*T0)/(6*12+1*6);
+disp("dU0 =")
+disp(dU0)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH11/EX11.33/33.sce b/551/CH11/EX11.33/33.sce new file mode 100755 index 000000000..ab319035c --- /dev/null +++ b/551/CH11/EX11.33/33.sce @@ -0,0 +1,11 @@ +clc
+// CO+1/2 O2 → CO2
+H_R0=1*9705+1/2*9696; //kJ
+H_RT=1*94080+1/2*99790; //kJ
+H_P0=1*10760; //kJ
+H_PT=1*149100; //kJ
+
+dH_T=-(285200+(143975-14553)-(149100-10760));
+disp("dH_T =")
+disp(dH_T)
+disp("kJ/mole")
\ No newline at end of file diff --git a/551/CH11/EX11.34/34.sce b/551/CH11/EX11.34/34.sce new file mode 100755 index 000000000..b3de1135a --- /dev/null +++ b/551/CH11/EX11.34/34.sce @@ -0,0 +1,20 @@ +clc
+disp("(i) Higher heating value at constant pressure")
+m=4*18;
+h_fg=2443; //kJ/kg
+LHVp=2044009; //kJ/kg
+R0=8.3143; //kJ/kg K
+T=298; //K
+
+HHVp=LHVp+m*h_fg;
+disp("HHVp =")
+disp(HHVp)
+disp("kJ/kg")
+
+disp("(ii) Higher heating value at constant volume")
+dn=3-(1+5);
+
+HHVv=HHVp+dn*R0*T;
+disp("HHVv =")
+disp(HHVv)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH11/EX11.35/35.sce b/551/CH11/EX11.35/35.sce new file mode 100755 index 000000000..236015966 --- /dev/null +++ b/551/CH11/EX11.35/35.sce @@ -0,0 +1,8 @@ +clc
+HHV=5494977; //kJ/kg
+m=9*18;
+u_fg=2305; //kJ/kg
+LHVv=HHV-m*u_fg;
+disp("LHVv =")
+disp(LHVv)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH11/EX11.36/36.sce b/551/CH11/EX11.36/36.sce new file mode 100755 index 000000000..7c1af694a --- /dev/null +++ b/551/CH11/EX11.36/36.sce @@ -0,0 +1,36 @@ +clc
+disp("(i) Air and benzene vapour ")
+
+// C6H6(g) + 7.5O2(g) + 7.5*(79/21)N2(g) = 6CO2(g) + 3H2O(g) + 7.5*(79/21)*N2(g)
+
+LHVp=3169500; //kJ/mole
+
+LHVv=LHVp/((12*6+6*1)+(7.5*32)+7.5*(79/21)*28)
+disp("LHVv per kg of mixture =")
+disp(LHVv)
+disp("kJ/kg")
+
+m=54; //kg/kg mole of fuel
+h_fg=2442; //kJ/kg
+
+HHVp=(LHVp+m*h_fg)/(78+240+790);
+disp("HHVp per kg of mixture =")
+disp(HHVp)
+disp("kJ/kg")
+
+disp("(ii) Air and octane vapour ")
+LHVp=5116200; //kJ/mole of C8H18
+
+// C8H18(g) + 12.5O2(g) → 8CO2(g) + 9H2O(g) + 12.5*(79/21)N2(g)
+
+LHVp1=LHVp/((12*8+18*1)+12.5*32+12.5*79/21*28);
+disp("LHVp per kg of mixture =")
+disp(LHVp1)
+disp("kJ/kg")
+
+m=9*18;
+HHVp=LHVp+m*h_fg;
+HHVp1=HHVp/(114+400+1317);
+disp("HHVp per kg of mixture =")
+disp(HHVp1)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH11/EX11.37/37.sce b/551/CH11/EX11.37/37.sce new file mode 100755 index 000000000..a8006f03d --- /dev/null +++ b/551/CH11/EX11.37/37.sce @@ -0,0 +1,32 @@ +clc
+m_CO2=44/12*0.88; //kg
+m_H2O=18/2*0.12; //kg
+u_fg=2304; //kJ/kg
+h_fg=2442; //kJ/kg
+HHVv=45670; //kJ/kg
+R0=8.3143; //kJ/kg K
+T=298; //K
+disp("(i) (LHV)v =")
+LHVv=HHVv-m_H2O*u_fg;
+disp(LHVv)
+disp("kJ/kg")
+
+disp("(ii) (HHV)p, (LHV)p")
+
+//1 mole fuel+x/32 O2-->3.23/44 CO2 + 1.08/18 H2O
+
+x=32*(m_CO2/44+m_H2O/18/2);
+
+// 1 kg fuel + 3.31 kg O2 = 3.23CO2 + 1.08H2O
+
+dn=(m_CO2/44-x/32);
+
+HHVp=HHVv-dn*R0*T;
+disp("HHVp =")
+disp(HHVp)
+disp("kJ/kg")
+
+LHVp=HHVp-m_H2O*h_fg;
+disp("LHVp =")
+disp(LHVp)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH11/EX11.4/4.sce b/551/CH11/EX11.4/4.sce new file mode 100755 index 000000000..02aa2ae55 --- /dev/null +++ b/551/CH11/EX11.4/4.sce @@ -0,0 +1,56 @@ +clc
+C=0.848; //kg
+H2=0.152; //kg
+O2_used=C*8/3 + H2*8;
+
+
+disp("(i) Minimum weight of air needed for combustion")
+w_min=O2_used*100/23;
+disp("Minimum weight of air needed for combustion=")
+disp(w_min)
+disp("kg")
+
+w_excess=w_min*0.15; //Excess air supplied
+
+w_O2=w_excess*23/100; //Weight of O2 in excess air
+
+w_total=w_min + w_excess; //Total air supplied for combustion
+w_N2=w_total*77/100; //Weight of N2 in flue gases
+
+
+disp("(ii) the volumetric composition of the products of combustion")
+
+//For CO2
+x1=3.109;
+y1=44;
+z1=x1/y1;
+
+//For O2
+x2=w_O2;
+y2=32;
+z2=x2/y2;
+
+//For N2
+x3=w_N2;
+y3=28;
+z3=x3/y3;
+
+z=z1+z2+z3;
+
+//For CO2
+%V1=z1/z*100;
+disp("%volume of CO2 =")
+disp(%V1)
+disp("%")
+
+//For O2
+%V2=z2/z*100;
+disp("%volume of O2 =")
+disp(%V2)
+disp("%")
+
+//For CO2
+%V3=z3/z*100;
+disp("%volume of N2 =")
+disp(%V3)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.5/5.sce b/551/CH11/EX11.5/5.sce new file mode 100755 index 000000000..92f8d7f8e --- /dev/null +++ b/551/CH11/EX11.5/5.sce @@ -0,0 +1,52 @@ +clc
+C=0.78;
+H2=0.06;
+O2=0.03;
+
+w_O2=C*8/3 + H2*8;
+w_min=(w_O2-O2)*100/23; //Minimum wt. of air needed for combustion
+
+disp("(i) Weight of dry flue gases per kg of fuel")
+
+//For CO2
+x1=0.104;
+y1=44;
+z1=x1*y1;
+
+//For CO
+x2=0.002;
+y2=28;
+z2=x2*y2;
+
+//For N2
+x3=0.816;
+y3=28;
+z3=x3*y3;
+
+//For O2
+x4=0.078;
+y4=32;
+z4=x4*y4;
+
+z=z1+z2+z3+z4;
+
+W_CO2=z1/z; //Weight per kg of flue gas
+W_CO=z2/z; //Weight per kg of flue gas
+W_N2=z3/z; //Weight per kg of flue gas
+W_O2=z4/z; //Weight per kg of flue gas
+
+amt=3/11*W_CO2 + 3/7*W_CO;
+
+W=C/amt; //Weight of dry flue gas per kg of fuel
+disp("Weight of dry flue gas per kg of fuel = ")
+disp(W)
+disp("kg")
+
+disp("(ii) Weight of excess air per kg of fuel")
+m_O2=W_O2-4/7*W_CO; //Weight of excess oxygen per kg of flue gas
+m_excess=W*m_O2; //Weight of excess O2 per kg of fuel
+
+w_excess=m_excess*100/23; //Weight of excess air per kg of fuel
+disp("Weight of excess air per kg of fuel=")
+disp(w_excess)
+disp("kg")
\ No newline at end of file diff --git a/551/CH11/EX11.6/6.sce b/551/CH11/EX11.6/6.sce new file mode 100755 index 000000000..bd617e13a --- /dev/null +++ b/551/CH11/EX11.6/6.sce @@ -0,0 +1,25 @@ +clc
+v_CO=0.05;
+v_CO2=0.10;
+v_H2=0.50;
+v_CH4=0.25;
+v_N2=0.10;
+
+V_fuel=1;
+
+V_O2=v_CO/2+v_H2/2+2*v_CH4; //Volume of O2 needed
+
+V_air=V_O2*100/21; //Volume of air required
+
+V_N2=V_air*79/100; //Volume of nitrogen in the air
+
+V=v_CO + v_CO2 + v_CH4 + v_N2 + V_N2; //Dry combustion products
+
+O2=6;
+V_excess=O2*V/(21-O2);
+
+V_total=V_air+V_excess;
+
+ratio=V_total/V_fuel;
+disp("Air fuel ratio=")
+disp(ratio)
\ No newline at end of file diff --git a/551/CH11/EX11.7/7.sce b/551/CH11/EX11.7/7.sce new file mode 100755 index 000000000..0b9b8fa26 --- /dev/null +++ b/551/CH11/EX11.7/7.sce @@ -0,0 +1,54 @@ +clc
+
+C=0.85;
+H2=0.15;
+
+//For CO2
+x1=0.115;
+y1=44;
+z1=x1*y1;
+
+//For CO
+x2=0.012;
+y2=28;
+z2=x2*y2;
+
+//For O2
+x3=0.009;
+y3=32;
+z3=x3*y3;
+
+//For N2
+x4=0.86;
+y4=28;
+z4=x4*y4;
+
+z=z1+z2+z3+z4;
+
+W_CO2=z1/z; //Weight per kg of flue gas
+W_CO=z2/z; //Weight per kg of flue gas
+W_O2=z3/z; //Weight per kg of flue gas
+W_N2=4/z; //Weight per kg of flue gas
+
+W_C=3/11*W_CO2 + 3/7*W_CO; //Weight of carbon per kg of flue gas
+
+W=C/W_C; //Weight of dry flue gas per kg of fuel
+
+Vapour=1.35; //kg; Vapour of combustion
+
+W_total=W+Vapour; //Total weight of gas
+
+W_air=W_total-1; //Air supplied
+
+ratio=W_air/1;
+disp("Ratio of air to petrol =")
+disp(ratio)
+
+S_air=[C*8/3 + H2*8]*100/23; //Stoichiometric air
+
+W_excess=W_air-S_air; //Excess air
+
+%Excess=W_excess/S_air*100; //Percentage excess air
+disp("Percentage excess air")
+disp(%Excess)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.8/8.sce b/551/CH11/EX11.8/8.sce new file mode 100755 index 000000000..cf055cb4d --- /dev/null +++ b/551/CH11/EX11.8/8.sce @@ -0,0 +1,77 @@ +clc
+C=0.86;
+H2=0.08;
+S=0.03;
+O2=0.02;
+
+W_O2=C*8/3 + H2*8 + S*1;
+
+A=W_O2-O2; //Weight of oxygen to be supplied per kg of fuel
+
+W_min=A*100/23;
+r_correct=1/W_min/1; //“correct” fuel-air ratio
+r_actual=1/12;
+
+
+disp("(i) Mixture strength")
+s=r_actual/r_correct*100; //Mixture strength
+
+richness=s-100;
+disp("richness=")
+disp(richness)
+disp("%")
+disp("This show that mixture is 6.5% rich.")
+
+D=1/r_correct-1/r_actual;
+
+CO=0.313; //kg
+CO2=2.662; //kg
+N2=9.24; //kg
+SO2=0.06; //kg
+
+disp("(ii) The percentage composition of dry flue gases")
+
+//For CO
+x1=0.313; //kg
+y1=28;
+z1=x1/y1;
+
+//For CO2
+x2=2.662; //kg
+y2=44;
+z2=x2/y2;
+
+//For N2
+x3=9.24; //kg
+y3=28;
+z3=x3/y3;
+
+//For SO2
+x4=0.06; //kg
+y4=64;
+z4=x4/y4;
+
+z=z1+z2+z3+z4;
+
+//Let percentage volume be denoted by V
+
+V_CO=z1/z*100;
+disp("Percentage volume of CO=")
+disp(V_CO)
+disp("%")
+
+V_CO2=z2/z*100;
+disp("Percentage volume of CO2=")
+disp(V_CO2)
+disp("%")
+
+V_N2=z3/z*100;
+disp("Percentage volume of N2=")
+disp(V_N2)
+disp("%")
+
+
+V_SO2=z4/z*100;
+disp("Percentage volume of SO2=")
+disp(V_SO2)
+disp("%")
\ No newline at end of file diff --git a/551/CH11/EX11.9/9.sce b/551/CH11/EX11.9/9.sce new file mode 100755 index 000000000..d664959d5 --- /dev/null +++ b/551/CH11/EX11.9/9.sce @@ -0,0 +1,54 @@ +clc
+
+A=992/284*100/23; //Air required for complete combustion
+
+B=13; //kg/kg of fuel; Air actually supplied
+
+D=A-B; //Deficiency of air
+
+W_CO2=0.466*11/3;
+W_CO=0.379*7/3;
+W_H2O=22/142*9;
+W_N2=13*0.77;
+
+//For CO2
+x1=W_CO2
+y1=44;
+z1=x1/y1;
+
+//For CO
+x2=W_CO;
+y2=28;
+z2=x2/y2;
+
+//For H2O
+x3=W_H2O;
+y3=18;
+z3=x3/y3;
+
+//For N2
+x4=W_N2;
+y4=28;
+z4=x4/y4;
+
+z=z1+z2+z3+z4;
+
+%CO2=z1/z*100;
+disp("Percentage of CO2=")
+disp(%CO2)
+disp("%")
+
+%CO=z2/z*100;
+disp("Percentage of CO=")
+disp(%CO)
+disp("%")
+
+%H2O=z3/z*100;
+disp("Percentage of H2O=")
+disp(%H2O)
+disp("%")
+
+%N2=z4/z*100;
+disp("Percentage of N2=")
+disp(%N2)
+disp("%")
\ No newline at end of file diff --git a/551/CH12/EX12.1/1.sce b/551/CH12/EX12.1/1.sce new file mode 100755 index 000000000..e46175302 --- /dev/null +++ b/551/CH12/EX12.1/1.sce @@ -0,0 +1,68 @@ +clc
+p1=60; //bar; Inlet to turbine
+p2=0.1; //bar; Exit from turbine
+p3=0.09; //bar; Exit from condenser
+p4=70; //bar ; Exit from pump
+p5=65; //bar; Exit from boiler
+
+t1=380; //0C
+t5=400; //0C
+
+x2=0.9; //Quality at exit from turbine
+
+C=200; //m/s; Velocity at the exit from turbine
+
+disp("(i) Power output of the turbine")
+
+//At 60 bar 380 0C, From steam tables
+
+h1=3123.5; //kJ/kg; By interpolation
+h_f2=191.8; //kJ/kg
+h_fg2=2392.8; //kJ/kg
+x2=0.9;
+
+h2=h_f2+x2*h_fg2;
+m_s=10000/3600; //Rate of stem flow in kg/s
+
+P=m_s*(h1-h2);
+disp("Power output of the turbine =")
+disp(P)
+disp("kW")
+
+
+disp("(ii) Heat transfer per hour in the boiler and condenser")
+
+h_f4=1267.4; //kJ/kg
+h_a=3167.6; //kJ/kg
+
+Q1=10000*(h_a - h_f4);
+disp("Heat transfer per hour in the boiler =")
+disp(Q1)
+disp("kJ/h")
+
+h_f3=183.3; //kJ/kg
+Q2=10000*(h2-h_f3);
+disp("Heat transfer per hour in the condenser =")
+disp(Q2)
+disp("kJ/h")
+
+
+disp("(iii) Mass of cooling water circulated per hour in the condenser")
+c_pw=4.18;
+t2=30;
+t1=20;
+
+m_w=Q2/c_pw/(t2-t1);
+disp("m_w=")
+disp(m_w)
+disp("kg/h")
+disp("This is the exact answer.")
+
+disp("(iv) Diameter of the pipe connecting turbine with condenser")
+
+v_g2=14.67; //m^3/kg
+
+d=sqrt(m_s*x2*v_g2*4/%pi/C)*1000;
+disp("Diameter =")
+disp(d)
+disp("mm")
\ No newline at end of file diff --git a/551/CH12/EX12.10/10.sce b/551/CH12/EX12.10/10.sce new file mode 100755 index 000000000..65bf9a00d --- /dev/null +++ b/551/CH12/EX12.10/10.sce @@ -0,0 +1,64 @@ +clc
+p2=2; //bar
+p3=1.1; //bar
+IP=1;
+m=12.8/3600; //kg/kWs
+n_mech=0.8; //Mechanical efficiency
+h1=3037.6; //kJ/kg
+v1=0.169; //m^3/kg
+s1=6.918; //kJ/kg K
+t_s2=120.2; //0C
+h_f2=504.7; //kJ/kg
+h_fg2=2201.6; //kJ/kg
+s_f2=1.5301; //kJ/kg K
+s_fg2=5.5967; //kJ/kg K
+v_f2=0.00106; //m^3/kg
+v_g2=0.885; //m^3/kg
+t_s3=102.3; //0C
+h_f3=428.8; //kJ/kg
+h_fg3=2250.8; //kJ/kg
+s_f3=1.333; //kJ/kg K
+s_fg3=5.9947; //kJ/kg K
+v_f3=0.001; //m^3/kg
+v_g3=1.549; //m^3/kg
+
+x2=(s1-s_f2)/s_fg2;
+h2=h_f2+x2*h_fg2;
+v2=x2*v_g2+(1-x2)*v_f2;
+
+disp("(i)Ideal work=")
+W=(h1-h2) + (p2-p3)*v2*100; //kJ/kg
+disp(W)
+disp("kJ/kg")
+
+
+disp("(ii) Rankine engine efficiency=")
+n_rankine=W/(h1-h_f3);
+disp(n_rankine)
+
+
+disp("(iii) Indicated and brake work per kg")
+W_indicated=IP/m;
+disp("Indicated worK =")
+disp(W_indicated)
+disp("kJ/kg")
+
+W_brake=n_mech*IP/m;
+disp("Brake work =")
+disp(W_brake)
+disp("kJ/kg")
+
+disp("(iv) Brake thermal efficiency=")
+n_brake=W_brake/(h1-h_f3);
+disp(n_brake)
+
+
+disp("(v) Relative efficiency :")
+
+n1=W_indicated/W; //on the basis of indicated work
+disp("Relative efficiency on the basis of indicated work=")
+disp(n1)
+
+n2=W_brake/W; //on the basis of brake work
+disp("Relative efficiency on the basis of brake work=")
+disp(n2)
\ No newline at end of file diff --git a/551/CH12/EX12.11/11.sce b/551/CH12/EX12.11/11.sce new file mode 100755 index 000000000..8b4deb494 --- /dev/null +++ b/551/CH12/EX12.11/11.sce @@ -0,0 +1,47 @@ +clc
+p2=0.75; //bar
+p3=0.3; //bar
+h1=3263.9; //kJ/kg
+v1=0.307; //m^3/kg
+s1=7.465; //kJ/kg K
+T_s2=369.7; //K
+h_g2=2670.9; //kJ/kg
+s_g2=7.3954; //kJ/kg K
+v_g2=1.869; //m^3/kg
+h_f3=289.3; //kJ/kg
+v_g3=5.229; //m^3/kg
+cp=2.1;
+
+disp("(i) Quality of steam at the end of expansion")
+T_sup2=T_s2*(%e^((s1-s_g2)/cp));
+t_sup2=T_sup2-273;
+disp("t_sup2=")
+disp(t_sup2)
+disp("°C")
+
+h2=h_g2+cp*(T_sup2-366.5);
+
+disp("(ii) Quality of steam at the end of constant volume operation, x3 :")
+v2=v_g2/T_s2*T_sup2;
+v3=v2;
+x3=v3/v_g3;
+disp("x3=")
+disp(x3)
+
+
+disp("(iii) Power developed")
+P=(h1-h2) + (p2-p3)*v2*100;
+disp("P=")
+disp(P)
+disp("kW")
+
+
+disp("(iv) Specific steam consumption =")
+ssc=3600/P;
+disp(ssc)
+disp("kg/kWh")
+
+
+disp("(v) Modified Rankine cycle efficiency =")
+n_mR=((h1-h2)+(p2-p3)*v2*100)/(h1-h_f3);
+disp(n_mR)
\ No newline at end of file diff --git a/551/CH12/EX12.12/12.sce b/551/CH12/EX12.12/12.sce new file mode 100755 index 000000000..6c929dab5 --- /dev/null +++ b/551/CH12/EX12.12/12.sce @@ -0,0 +1,19 @@ +clc
+h1=3100; //kJ/kg
+h2=2100; //kJ/kg
+h3=2500; //kJ/kg
+h_f2=570.9; //kJ/kg
+h_f5=125; //kJ/kg
+h_f2=570.9; //kJ/kg
+a=11200; //Quantity of bled steam in kg/h
+
+m=(h_f2-h_f5)/(h2-h_f5);
+
+S=a/m; //Steam supplied to the turbine per hour
+
+W_net=(h1-h3) + (1-m)*(h3-h2);
+
+P=W_net*S/3600; //Power developed by the turbine
+disp("Power developed by the turbine=")
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH12/EX12.13/13.sce b/551/CH12/EX12.13/13.sce new file mode 100755 index 000000000..8dc0fa663 --- /dev/null +++ b/551/CH12/EX12.13/13.sce @@ -0,0 +1,69 @@ +clc
+//At 30bar, 400 0C
+
+h1=3230.9; //kJ/kg
+s1=6.921; //kJ/kg
+s2=s1;
+s3=s1;
+//At 5 bar
+s_f1=1.8604;
+s_g1=6.8192; //kJ/kg K
+h_f1=640.1; //kJ/kg
+
+t2=172 //0C
+h2=2796; //kJ/kg
+
+//At 0.1 bar
+s_f3=0.649; //kJ/kg K
+s_fg3=7.501; //kJ/kg K
+h_f3=191.8; //kJ/kg
+h_fg3=2392.8; //kJ/kg
+
+x3=(s2-s_f3)/s_fg3;
+h3=h_f3+x3*h_fg3;
+
+h_f4=191.8; //kJ/kg
+h_f5=h_f4;
+
+h_f6=640.1; //kJ/kg
+h_f7=h_f6;
+s7=1.8604; //kJ/kg K
+s4=0.649; //kJ/kg K
+
+m=(h_f6-h_f5)/(h2-h_f5);
+
+W_T=(h1-h2) + (1-m)*(h2-h3);
+
+Q1=h1-h_f6;
+
+disp("(i) Efficiency of cycle =")
+n_cycle=W_T/Q1;
+disp(n_cycle)
+
+SR=3600/W_T; //Steam rate
+disp("Steam rate =")
+disp(SR)
+disp("kg/kWh")
+
+
+T_m1=(h1-h_f7)/(s1-s7);
+
+T_m1r=(h1-h_f4)/(s1-s4); //Without regeneration
+
+dT_m1=T_m1-T_m1r;
+disp("Increase in T_m1 due to regeneration=")
+disp(dT_m1)
+disp("0C")
+
+W_Tr=h1-h3; //Without regeneration
+SR1=3600/W_Tr; //Steam rate without regeneration
+dSR=SR-SR1;
+disp("Increase in steam rate due to regeneration=")
+disp(dSR)
+disp("kg/kWh")
+
+n_cycle1=(h1-h3)/(h1-h_f4); //without regeneration
+dn_cycle=n_cycle-n_cycle1;
+disp("Increase in cycle efficiency due to regeneration")
+disp(dn_cycle*100)
+disp("%")
diff --git a/551/CH12/EX12.14/14.sce b/551/CH12/EX12.14/14.sce new file mode 100755 index 000000000..d1fe895af --- /dev/null +++ b/551/CH12/EX12.14/14.sce @@ -0,0 +1,32 @@ +clc
+
+//At 3 bar
+t_s1=133.5; //0C
+h_f1=561.4; //kJ/kg
+
+//At 0.04 bar
+t_s2=29; //0C
+h_f2=121.5; //0C
+
+h0=3231; //kJ/kg
+h1=2700; //kJ/kg
+h2=2085; //kJ/kg
+
+t1=130; //0C
+t2=27; //0C
+c=4.186;
+
+disp("(i) Mass of steam used")
+m1=c*(t1-t2)/(h1-h_f2);
+disp("m1=")
+disp(m1)
+disp("kg")
+
+
+disp("(ii) Thermal efficiency of the cycle")
+W=(h0-h1)+(1-m1)*(h1-h2);
+Q=h0-c*t1;
+
+n_thermal=W/Q;
+disp("n_thermal=")
+disp(n_thermal)
diff --git a/551/CH12/EX12.15/15.sce b/551/CH12/EX12.15/15.sce new file mode 100755 index 000000000..833d549be --- /dev/null +++ b/551/CH12/EX12.15/15.sce @@ -0,0 +1,27 @@ +clc
+
+h0=3115.3; //kJ/kg
+h1=2720; //kJ/kg
+h2=2450; //kJ/kg
+h3=2120; //kJ/kg
+
+h_f1=640.1; //kJ/kg
+h_f2=417.5; //kJ/kg
+h_f3=173.9; //kJ/kg
+
+m1=(h_f1-h_f2)/(h1-h_f1);
+disp("m1=")
+disp(m1)
+disp("kJ/kg")
+
+m2=((h_f2-h_f3)-m1*(h_f1-h_f3))/(h2-h_f3);
+disp("m2=")
+disp(m2)
+disp("kJ/kg")
+
+W=h0-h1 + (1-m1)*(h1-h2) + (1-m1-m2)*(h2-h3);
+Q=h0-h_f1;
+
+n=W/Q;
+disp("Thermal Efficiency of the cycle=")
+disp(n)
\ No newline at end of file diff --git a/551/CH12/EX12.16/16.sce b/551/CH12/EX12.16/16.sce new file mode 100755 index 000000000..1a570cc46 --- /dev/null +++ b/551/CH12/EX12.16/16.sce @@ -0,0 +1,68 @@ +clc
+h0=2905; //kJ/kg
+h1=2600; //kJ/kg
+h2=2430; //kJ/kg
+h3=2210; //kJ/kg
+h4=2000; //kJ/kg
+
+h_f1=640.1; //kJ/kg
+h_f2=467.1; //kJ/kg
+h_f3=289.3; //kJ/kg
+h_f4=137.8; //kJ/kg
+
+disp("(i) Mass of bled steam")
+
+m1=(h_f1-h_f2)/(h1-h_f1);
+disp("m1=")
+disp(m1)
+disp("kJ/kg")
+
+m2=((h_f2-h_f3) - (m1*(h_f1-h_f2)))/(h2-h_f2);
+disp("m2=")
+disp(m2)
+disp("kJ/kg")
+
+m3=((h_f3-h_f4)-(m1+m2)*(h_f2-h_f4))/(h3-h_f4);
+disp("m3=")
+disp(m3)
+disp("kJ/kg")
+
+W=(h0-h1) + (1-m1)*(h1-h2)+(1-m1-m2)*(h2-h3) + (1-m1-m2-m3)*(h3-h4);
+
+Q=h0-h_f1;
+
+disp("(ii) Thermal efficiency of the cycle=")
+n_thermal=W/Q;
+disp(n_thermal)
+
+
+disp("(iii) Thermal efficiency of Rankine cycle =")
+n_rankine=(h0-h4)/(h0-h_f4);
+disp(n_rankine)
+
+
+disp("(iv) Theoretical gain due to regenerative feed heating =")
+gain=(n_thermal-n_rankine)/(n_thermal);
+disp(gain)
+
+disp("(v) Steam consumption with regenerative feed heating =")
+S1=3600/W;
+disp(S1)
+disp("kg/kWh")
+
+disp("Steam consumption without regenerative feed heating =")
+S2=3600/(h0-h4);
+disp(S2)
+disp("kg/kWh")
+
+disp("(vi) Quantity of steam passing through the last stage of a 50000 kW turbine with regenerative feed-heating =")
+quantity1=S1*(1-m1-m2-m3)*50000;
+disp(quantity1)
+disp("kg/h")
+
+disp("quantity of steam without regeneration =")
+quantity2=S2*50000;
+disp(quantity2)
+disp("kg/h")
+
+
diff --git a/551/CH12/EX12.17/17.sce b/551/CH12/EX12.17/17.sce new file mode 100755 index 000000000..7f5bc583d --- /dev/null +++ b/551/CH12/EX12.17/17.sce @@ -0,0 +1,65 @@ +clc
+h1=3460; //kJ/kg
+h2=3460; //kJ/kg
+h3=3111.5; //kJ/kg
+h4=3585; //kJ/kg
+h5=3207; //kJ/kg
+h6=2466; //kJ/kg
+h7=137.8; //kJ/kg
+h8=962; //kJ/kg
+h9=670.4; //kJ/kg
+h10=962; //kJ/kg
+
+p1=100; //bar
+p2=95; //bar
+p3=25; //bar
+p4=22; //bar
+p5=6; //bar
+p6=0.05; //bar
+
+n_mech=0.9;
+n_gen=0.96;
+n_boiler=0.9;
+
+P=120*10^3; //kW
+
+m1=(h10-h9)/(h3-h8);
+
+m2=(h9-m1*h8-(1-m1)*h7)/(h5-h7);
+
+W_IP=(1-m1-m2)*(p5-p6)*0.001*10^2;
+W_HP=(p1-p5)*0.001*10^2;
+
+W_total=(W_IP+W_HP)/n_mech;
+
+W_indicated=(h2-h3) + (1-m1)*(h4-h5) + (1-m1-m2)*(h5-h6);
+
+Output=(W_indicated - W_total)*n_mech*n_gen; //net electrical output
+
+rate=P*3600/Output;
+
+amt1=m1*rate; //Amounts of bled off, surface(high pressure) heater
+disp("Amounts of bled off, surface(high pressure) heater =")
+disp(amt1)
+disp("kg/h")
+
+amt2=m2*rate; //Amounts of bled off, surface(low pressure) heater
+disp("Amounts of bled off, surface(low pressure) heater")
+disp(amt2)
+disp("kg/h")
+
+
+disp("(iii) Overall thermal efficiency")
+Q_boiler=(h1-h10)/n_boiler;
+Q_reheater=(h4-h3)/n_boiler;
+
+n_overall=Output/(Q_boiler+Q_reheater)*100;
+disp("Overall thermal efficiency =")
+disp(n_overall)
+disp("%")
+
+
+disp("(iv) Specific steam consumption =")
+ssc=rate/P; //Specific steam consumption
+disp(ssc)
+disp("kg/kWh")
\ No newline at end of file diff --git a/551/CH12/EX12.18/18.sce b/551/CH12/EX12.18/18.sce new file mode 100755 index 000000000..b0ee7449e --- /dev/null +++ b/551/CH12/EX12.18/18.sce @@ -0,0 +1,26 @@ +clc
+p1=15; //bar
+p2=4; //bar
+p4=0.1; //bar
+
+h1=2920; //kJ/kg
+h2=2660; //kJ/kg
+h3=2960; //kJ/kg
+h4=2335; //kJ/kg
+
+W=h1-h2+h3-h4;
+disp("work done per kg of steam")
+disp(W)
+disp("kJ/kg")
+
+h_reheat=h3-h2;
+disp("Amount of heat supplied during reheat =")
+disp(h_reheat)
+disp("kJ/kg")
+
+h_4a=2125; //kJ/kg
+
+W1=h1-h_4a;
+disp("Work output without reheat =")
+disp(W1)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH12/EX12.19/19.sce b/551/CH12/EX12.19/19.sce new file mode 100755 index 000000000..b15a9e539 --- /dev/null +++ b/551/CH12/EX12.19/19.sce @@ -0,0 +1,24 @@ +clc
+
+h1=3450; //kJ/kg
+h2=3050; //kJ/kg
+h3=3560; //kJ/kg
+h4=2300; //kJ/kg
+
+h_f4=191.8; //kJ/kg
+
+//From mollier diagram
+x4=0.88;
+disp("(i)Quality of steam at turbine exhaust =")
+disp(x4)
+
+
+n_cycle=((h1-h2) + (h3-h4))/((h1-h_f4) + (h3-h2));
+disp("(ii) Cycle efficiency =")
+disp(n_cycle)
+
+
+SR=3600/((h1-h2) + (h3-h4));
+disp("(iii) Steam rate in kg/kWh =")
+disp(SR)
+disp("kg/kWh")
\ No newline at end of file diff --git a/551/CH12/EX12.2/2.sce b/551/CH12/EX12.2/2.sce new file mode 100755 index 000000000..2e9fd4968 --- /dev/null +++ b/551/CH12/EX12.2/2.sce @@ -0,0 +1,30 @@ +clc
+p1=15; //bar
+x1=1;
+p2=0.4; //bar
+
+//At 15 bar
+t_s1=198.3; //0C
+h_g1=2789.9; //kJ/kg
+s_g1=6.4406; //kJ/kg K
+
+//At 0..4 bar
+t_s2=198.3; //0C
+h_f2=317.7; //kJ/kg
+h_fg2=2319.2; //kJ/kg
+s_f2=1.0261; //kJ/kg K
+s_fg2=6.6448; //kJ/kg K
+T1=471.3; //K
+T2=348.9; //K
+
+n_carnot=(T1-T2)/T1;
+disp("Carnot efficiency=")
+disp(n_carnot)
+
+
+x2=(s_g1 - s_f2)/s_fg2;
+h2=h_f2+x2*h_fg2;
+
+n_rankine=(h_g1-h2)/(h_g1-h_f2);
+disp("Rankine efficiency=")
+disp(n_rankine)
\ No newline at end of file diff --git a/551/CH12/EX12.20/20.sce b/551/CH12/EX12.20/20.sce new file mode 100755 index 000000000..7d3d6a631 --- /dev/null +++ b/551/CH12/EX12.20/20.sce @@ -0,0 +1,35 @@ +clc
+
+h1=3250; //kJ/kg
+h2=2170; //kJ/kg
+h_f2=173.9; //kJ/kg
+
+W=h1-h2;
+Q=h1-h_f2;
+
+n_thermal=W/Q;
+disp("Thermal effifciency=")
+disp(n_thermal);
+
+x2=0.83; //From mollier chart
+disp("x2=")
+disp(x2)
+
+
+disp("Second case")
+
+h1=3250; //kJ/kg
+h2=2807; //kJ/kg
+h3=3263; //kJ/kg
+h4=2426; //kJ/kg
+h_f4=173.9; //kJ/kg
+W=h1-h2+h3-h4;
+Q=h1-h_f4+h3-h2;
+
+n_thermal=W/Q;
+disp("Thermal effifciency=")
+disp(n_thermal);
+
+x4=0.935; //From mollier chart
+disp("x4=")
+disp(x4)
diff --git a/551/CH12/EX12.21/21.sce b/551/CH12/EX12.21/21.sce new file mode 100755 index 000000000..46d2bfe8f --- /dev/null +++ b/551/CH12/EX12.21/21.sce @@ -0,0 +1,47 @@ +clc
+
+disp("(a) The erosion of the moving blades is caused by the presence of water particles in (wet) steam in the L.P. stages. The water particles strike the leading surface of the blades. Such impact, if sufficiently heavy, produces severe local stresses in the blade material causing the surface metal to fail and flake off.")
+
+disp(" The erosion, if any, is more likely to occur in the region where the steam is wettest, i.e., in the last one or two stages of the turbine. Moreover, the water droplets are concentrated in the outer parts of the flow annuals where the velocity of impact is highest.")
+disp("Erosion difficulties due to moisture in the steam may be avoided by reheating. The whole of steam is taken from the turbine at a suitable point 2, and a further supply of heat is given to it along 2-3 after which the steam is readmitted to the turbine and expanded along 3-4 to condenser pressure. Erosion may also be reduced by using steam traps in between the stages to separate moisture from the steam.")
+
+
+
+disp("(b) TTD means “Terminal temperature difference”. It is the difference between temperatures of bled steam/condensate and the feed water at the two ends of the feed water heater")
+
+
+
+disp("Part (c)")
+
+h1=3580; //kJ/kg
+h2=3140; //kJ/kg
+h3=3675; //kJ/kg
+h4=2335; //kJ/kg
+h5=191.8; //kJ/kg
+
+P=15*10^3; //kW
+a=0.104; //moisture content in exit from LP turbine
+
+p=40; //bar; From the mollier diagram
+disp("(i)Reheat pressure=")
+disp(p)
+disp("bar")
+
+disp("(ii) Thermal efficiency")
+W=h1-h2+h3-h4;
+Q=h1-h5+h3-h2;
+n_th=W/Q*100;
+disp("n_th=")
+disp(n_th)
+disp("%")
+
+sc=P/W;//steam consumption
+ssc=sc*3600/P; //specific steam consumption
+disp("Specific steam consumption=")
+disp(ssc)
+disp("kg/kWh")
+
+disp("(iv) Rate of pump work =")
+rate=sc*0.15;
+disp(rate)
+
diff --git a/551/CH12/EX12.22/22.sce b/551/CH12/EX12.22/22.sce new file mode 100755 index 000000000..d3f3b66ef --- /dev/null +++ b/551/CH12/EX12.22/22.sce @@ -0,0 +1,83 @@ +clc
+
+h_l=355.988; //kJ/kg
+s_l=0.5397; //kJ/kg K
+s_f=0.0808; //kJ/kg K
+s_g=0.6925; //kJ/kg K
+h_f=29.98; //kJ/kg
+h_g=329.85; //kJ/kg
+
+p1=4; //bar
+p2=0.04; //bar
+v_f2=76.5*10^(-6); //m^3/kg
+
+h1=2789.9; //kJ/kg
+s1=6.4406; //kJ/kg
+h_f=121.5; //kJ/kg
+h_fg=2432.9; //kJ/kg
+s_f=0.432; //kJ/kg K
+s_fg2=8.052; //kJ/kg K
+
+p4=15; //bar
+p3=0.04; //bar
+
+v_f=0.0001; //kJ/kg K
+
+h_f4=123; //kJ/kg
+h_m=254.88; //kJ/kg
+h_fn=29.98; //kJ/kg
+h_fk=29.988; //kJ/kg
+
+disp("(i) Overall thermal efficiency ")
+m=(h1-h_f4)/(h_m-h_fn); //The amount of mercury circulating for 1kg of steam in the bottom cycle
+Q1=m*(h_l-h_fk); //total
+
+x2=(s1-s_f)/(s_fg2);
+
+h2=h_f+x2*h_fg;
+
+W_T=m*(h_l-h_m)+(h1-h2); //total
+
+n_overall=W_T/Q1; //W_P may be neglected
+disp("n_overall =")
+disp(n_overall)
+
+
+disp("(ii) Flow through mercury turbine=")
+A=48000; //kg/h
+m_Hg=m*A;
+disp(m_Hg)
+disp("kg/h")
+
+
+disp("(iii) Useful work in binary vapour cycle=")
+W_total=A*W_T/3600;
+disp(W_total)
+disp("kW")
+
+
+disp("(iv) Overall efficiency under new conditions ")
+n_Hg=0.84;
+n_steam=0.88;
+
+W_Hg=n_Hg*101.1;
+h_m1=h_l-W_Hg;
+m1=(h1-h_f4)/(h_m1-h_fn);
+
+h_g=3037.6; //kJ/kg
+s_g=6.918; //kJ/kg
+s_f2=0.423; //kJ/kg K
+s_fg2=8.052; //kJ/kg K
+
+Q1=m1*(h_l - h_fk) + (h_g-h1);
+
+x2=(s_g-s_f2)/s_fg2;
+h2=h_f+x2*h_fg;
+
+W_steam=n_steam*(h_g-h2);
+
+W_total=m1*W_Hg + W_steam;
+
+n_overall=W_total/Q1;
+disp("n_overall")
+disp(n_overall)
\ No newline at end of file diff --git a/551/CH12/EX12.23/23.sce b/551/CH12/EX12.23/23.sce new file mode 100755 index 000000000..7aa009e5e --- /dev/null +++ b/551/CH12/EX12.23/23.sce @@ -0,0 +1,48 @@ +clc
+p1=60; //bar
+t1=450; //0C
+p2=3; //bar
+p3=0.07; //bar; p3=(760-707.5)/760*1.013
+
+n_turbine=0.87;
+n_boiler=0.86;
+n_alt=0.94;
+n_mech=0.97;
+
+P=22500; //kW
+
+h1=3300; //kJ/kg
+h2=2607; //kJ/kg
+
+h2a=h1-n_turbine*(h1-h2);
+h3=2165; //kJ/kg
+
+h3a=h2a-n_turbine*(h2a-h3);
+
+h_f4=163.4; //kJ/kg
+h_f5=561.4; //kJ/kg
+
+disp("(i) The steam bled per kg of steam supplied to the turbine")
+m=(h_f5-h_f4)/(h2a-h_f4);
+disp("m=")
+disp(m)
+disp("kJ/kg")
+
+
+disp("(ii) Steam generated per hour")
+W=(h1-h2a) + (1-m)*(h2a-h3a); //Work developed per kg of steam in the turbine
+W_act=P/n_alt/n_mech; //actual work
+
+steam=W_act/W*3600/1000; //tonnes/h
+disp("Steam generated=")
+disp(steam)
+disp("tonnes/h")
+
+
+disp("(iii) The overall efficiency of the plant")
+P_avail=P*(1-0.09); //Net power available deducting pump power
+Q=steam*1000*(h1-h_f5)/n_boiler/3600; //kW
+
+n_overall=P_avail/Q
+disp("n_overall=")
+disp(n_overall)
\ No newline at end of file diff --git a/551/CH12/EX12.24/24.sce b/551/CH12/EX12.24/24.sce new file mode 100755 index 000000000..9a8491920 --- /dev/null +++ b/551/CH12/EX12.24/24.sce @@ -0,0 +1,36 @@ +clc
+t1=350; //0C
+t_s=350; //0C
+
+p2=7; //bar
+p3=7; //bar
+p4=0.4; //bar
+t3=350; //0C
+
+h1=2985; //kJ/kg
+h2=2520; //kJ/kg
+h3=3170; //kJ/kg
+h4=2555; //kJ/kg
+
+h_f2=697.1; //kJ/kg
+h_f4=317.7; //kJ/kg
+
+P=110*10^3; //kW
+
+disp("(i) The ratio of steam bled to steam generated")
+m=(h_f2-h_f4)/(h2-h_f4);
+
+ratio=1/m;
+disp("ratio=")
+disp(ratio)
+
+
+disp("(ii) The boiler generating capacity =")
+m_s=P/(h1-h2+(1-m)*(h3-h4))*3600/1000; //tonnes/hour
+disp(m_s)
+disp("tonnes/hour")
+
+
+disp("(iii) Thermal efficiency of the cycle =")
+n_thermal=((h1-h2) + (1-m)*(h3-h4))/((h1-h_f2)+(1-m)*(h3-h2));
+disp(n_thermal)
\ No newline at end of file diff --git a/551/CH12/EX12.25/25.sce b/551/CH12/EX12.25/25.sce new file mode 100755 index 000000000..c3335a32a --- /dev/null +++ b/551/CH12/EX12.25/25.sce @@ -0,0 +1,49 @@ +clc
+h1=3315; //kJ/kg
+h2=2716; //kJ/kg
+h3=3165; //kJ/kg
+h4=2236; //kJ/kg
+h_f2=697.1;//kJ/kg
+h_f6=h_f2;
+h_f4=111.9; //kJ/kg
+h_f5=h_f4;
+
+disp("(i) Amount of steam bled off for feed heating =")
+m=(h_f2-h_f4)/(h2-h_f4);
+disp(m)
+disp("steam bled off is 22.5% of steam generated by the boiler.")
+
+
+disp("(ii) Amount of steam supplied to L.P. turbine =")
+amt=100-m*100;
+disp(amt)
+disp("77.5% of the steam generated by the boiler.")
+
+
+disp("(iii) Heat supplied in the boiler and reheater")
+Q_boiler=h1-h_f6;
+disp("Q_boiler=")
+disp(Q_boiler)
+disp("kJ/kg")
+
+Q_reheater=(1-m)*(h3-h2);
+disp("Q_reheater=")
+disp(Q_reheater)
+disp("kJ/kg")
+
+Qs=Q_boiler+Q_reheater;
+
+disp("(iv) Cycle efficiency")
+W=h1-h2 + (1-m)*(h3-h4);
+
+n_cycle=W/Qs;
+disp("n_cycle=")
+disp(n_cycle)
+
+
+disp("(v) Power developed by the system")
+ms=50; //kg/s
+Power=ms*W/1000; //MW
+disp("Power=")
+disp(Power)
+disp("MW")
\ No newline at end of file diff --git a/551/CH12/EX12.26/26.sce b/551/CH12/EX12.26/26.sce new file mode 100755 index 000000000..71423ee2d --- /dev/null +++ b/551/CH12/EX12.26/26.sce @@ -0,0 +1,54 @@ +clc
+
+h1 = 3578; //kJ/kg
+h2 = 3140; //kJ/kg
+h3 = 3678; //kJ/kg
+h4 = 3000; //kJ/kg
+h5 = 2330; //kJ/kg
+h_f1=1611; //kJ/kg
+h_f2=1087.4; //kJ/kg
+h_f4=640.1; //kJ/kg
+h_f5=191.8; //kJ/kg
+h_f6=h_f5;
+
+disp("(i) Fraction of steam extracted from the turbines at each bled heater =")
+
+disp("closed feed heater")
+m1=(h_f2-h_f4)/(h2-h_f4);
+disp(m1)
+disp("kg/kg of steam supplied by the boiler")
+
+disp("open feed heater")
+m2=(1-m1)*(h_f4-h_f5)/(h4-h_f6);
+disp(m2)
+disp("kg/kg of steam supplied by the boiler")
+
+
+disp("(ii) Thermal efficiency of the system")
+
+W_total=(h1-h2) + (1-m1)*(h3-h4) + (1-m1-m2)*(h4-h5);
+p1=150; //bar
+p2=40; //bar
+p4=5; //bar
+p5=0.1; //bar
+
+v_w1=1/1000; //m^3/kg
+v_w2=v_w1;
+v_w3=v_w1;
+
+W_P1=v_w1*(1-m1-m2)*(p4-p5)*100; //kJ/kg
+W_P2=v_w2*(1-m1)*(p1-p4)*100; //kJ/kg
+W_P3=v_w3*m1*(p1-p2)*100; //kJ/kg
+
+W_P=W_P1+W_P2+W_P3; //Total pump work
+W_net=W_total-W_P;
+
+Q=(1-m1)*h_f1 +m1*(h_f1); //Heat of feed water extering the boiler
+Qs1=h1-Q;
+Qs2=(1-m1)*(h3-h2);
+Qst=Qs1+Qs2;
+
+n_thermal=W_net/Qst*100;
+disp("n_thermal=")
+disp(n_thermal)
+disp("%")
\ No newline at end of file diff --git a/551/CH12/EX12.27/27.sce b/551/CH12/EX12.27/27.sce new file mode 100755 index 000000000..a497318cb --- /dev/null +++ b/551/CH12/EX12.27/27.sce @@ -0,0 +1,31 @@ +clc
+
+disp("(i) The minimum pressure at which bleeding is necessary=")
+
+//It would be assumed that the feed water heater is an open heater. Feed water is heated to 180°C. So psat at 180°C ~= 10 bar is the pressure at which the heater operates. Thus, the pressure at which bleeding is necessary is 10 bar.
+p_min=10; //bar
+disp(p_min)
+disp("bar")
+
+h1=3285; //kJ/kg
+h2=2980; //kJ/kg
+h3=3280; //kJ/kg
+h4a=3072.5; //kJ/kg
+h5=2210; //kJ/kg
+h5a=2356.6; //kJ/kg
+
+h_f6=163.4; //kJ/kg
+h_f8=762.6; //kJ/kg
+h2a=3045.6; //kJ/kg
+
+
+disp("(ii) The quantity of steam bled per kg of flow at the turbine inlet =")
+m=(h_f8-h_f6)/(h4a-h_f6);
+disp(m)
+disp("kg of steam flow at turbine inlet.")
+
+
+disp("(iii) Cycle efficiency =")
+n_cycle=((h1-h2a)+(h3-h4a)+(1-m)*(h4a-h5a))/((h1-h_f8) + (h3 - h2a))*100;
+disp(n_cycle)
+disp("%")
\ No newline at end of file diff --git a/551/CH12/EX12.3/3.sce b/551/CH12/EX12.3/3.sce new file mode 100755 index 000000000..5800f34ef --- /dev/null +++ b/551/CH12/EX12.3/3.sce @@ -0,0 +1,36 @@ +clc
+p1=20; //bar
+p2=0.08; //bar
+
+//At 20 bar, 360 0C
+
+h1=3159.3; //kJ/kg
+s1=6.9917; //kJ/kg K
+
+//At 0.08 bar
+h_f2=173.88; //kJ/kg
+s_f2=0.5926; //kJ/kg K
+
+h_fg2=2403.1; //kJ/kg
+s_g=8.2287; //kJ/kg K
+v_f=0.001008; //m^3/kg
+s_fg=7.6361; //kJ/kg K
+
+x2=(s1-s_f2)/s_fg;
+
+h2=h_f2+x2*h_fg2;
+
+W_pump=v_f*(p1-p2)*100; //kJ/kg
+W_turbine=h1-h2;
+
+W_net=h1-h2;
+disp("Net work done=")
+disp(W_net)
+disp("kJ/kg")
+
+h_f4=W_pump+h_f2;
+Q1=h1-h_f4;
+
+n_cycle=W_net/Q1;
+disp("Cycle efficiency=")
+disp(n_cycle)
diff --git a/551/CH12/EX12.4/4.sce b/551/CH12/EX12.4/4.sce new file mode 100755 index 000000000..260a8d88c --- /dev/null +++ b/551/CH12/EX12.4/4.sce @@ -0,0 +1,35 @@ +clc
+
+n_turbine=0.9;
+n_pump=0.8;
+p1=80; //bar
+p2=0.1; //bar
+v_f=0.0010103; //m^3
+
+//At 80 bar, 600 0C
+h1=3642; //kJ/kg
+s1=7.0206; //kJ/kg K
+s_f2=0.6488; //kJ/kg K
+s_fg2=7.5006; //kJ/kg K
+h_f2=191.9; //kJ/kg
+h_fg2=2392.3; //kJ/kg
+
+x2=(s1-s_f2)/s_fg2;
+h2=h_f2+x2*h_fg2;
+
+W_turbine=n_turbine*(h1-h2);
+W_pump=v_f*(p1-p2)*10^2;
+
+W_actual=W_pump/n_pump; //Actual pump work
+
+W_net=W_turbine - W_actual;
+disp("Specific work =")
+disp(W_net)
+disp("kJ/kg")
+
+h_f4=h_f2+W_actual;
+Q1=h1-h_f4;
+
+n_thermal=W_net/Q1; //Thermal efficiency
+disp("Thermal efficiency =")
+disp(n_thermal)
\ No newline at end of file diff --git a/551/CH12/EX12.5/5.sce b/551/CH12/EX12.5/5.sce new file mode 100755 index 000000000..387aa425e --- /dev/null +++ b/551/CH12/EX12.5/5.sce @@ -0,0 +1,39 @@ +clc
+p1=28; //bar
+p2=0.06; //bar
+
+//At 28 bar
+h1=2802; //kJ/kg
+s1=6.2104; //kJ/kg K
+
+//At 0.06 bar
+h_f2=151.5; //kJ/kg
+h_f3=h_f2;
+h_fg2=2415.9; //kJ/kg
+s_f2=0.521; //kJ/kg K
+s_fg2=7.809; //kJ/kg K
+v_f=0.001; //m^3/kg
+
+x2=(s1-s_f2)/s_fg2;
+
+h2=h_f2 + x2*h_fg2;
+
+W_turbine=h1-h2;
+W_pump=v_f*(p1-p2)*100; //kJ/kg
+
+h_f4=h_f2+W_pump;
+Q1=h1-h_f4;
+W_net=W_turbine - W_pump;
+
+n_cycle=W_net/Q1;
+disp("cyclic efficiency =")
+disp(n_cycle)
+
+ratio=W_net/W_turbine; //Work ratio
+disp("Work ratio =")
+disp(ratio)
+
+S=3600/W_net; //Specific steam combustion
+disp("Specific steam combustion=")
+disp(S)
+disp("kg/kWh")
\ No newline at end of file diff --git a/551/CH12/EX12.6/6.sce b/551/CH12/EX12.6/6.sce new file mode 100755 index 000000000..256b8728e --- /dev/null +++ b/551/CH12/EX12.6/6.sce @@ -0,0 +1,52 @@ +clc
+p1=35; //bar
+x=1;
+p2=0.2; //bar
+m=9.5; //kg/s
+
+//At 35 bar
+h1=2802; //kJ/kg
+h_g1=h1;
+s_g1=6.1228; //kJ/kg K
+
+//At0.26 bar
+h_f=251.5; //kJ/kg
+h_fg=2358.4; //kJ/kg
+v_f=0.001017; //m^3/kg
+s_f=0.8321; //kJ/kg
+s_fg=7.0773; //kJ/kg K
+
+disp("(i) The pump work")
+W_pump=v_f*(p1-p2)*100; //kJ/kg
+P=m*W_pump; //power required
+disp("Power required to drive the pump")
+disp(P)
+disp("kW")
+
+
+disp("(ii) The turbine work")
+
+x2=(s_g1-s_f)/s_fg;
+h2=h_f+x2*h_fg;
+
+W_turbine=m*(h1-h2);
+disp("Turbine work=")
+disp(W_turbine)
+disp("kW")
+
+
+disp("(iii) The Rankine efficiency")
+n_rankine=(h1-h2)/(h1-h_f);
+disp("rankine efficiency=")
+disp(n_rankine)
+
+
+disp("(iv) The condenser heat flow :")
+Q=m*(h2-h_f);
+disp("The condenser heat flow=")
+disp(Q)
+disp("kW")
+
+
+disp("(v) The dryness at the end of expansion=")
+disp(x2)
\ No newline at end of file diff --git a/551/CH12/EX12.7/7.sce b/551/CH12/EX12.7/7.sce new file mode 100755 index 000000000..2a7e15448 --- /dev/null +++ b/551/CH12/EX12.7/7.sce @@ -0,0 +1,14 @@ +clc
+dh=840; //kJ/kg; Adiabatic enthalpy drop
+h1=2940; ///kJ/kg;
+p2=0.1; //bar
+h_f2=191.8; //kJ/kg
+
+n_rankine=(dh)/(h1-h_f2)*100;
+disp("rankine efficiency=")
+disp(n_rankine)
+
+S=3600/dh; //Specific steam combustion
+disp("Specific steam combustion=")
+disp(S)
+disp("kg/kWh")
\ No newline at end of file diff --git a/551/CH12/EX12.8/8.sce b/551/CH12/EX12.8/8.sce new file mode 100755 index 000000000..f4d57296f --- /dev/null +++ b/551/CH12/EX12.8/8.sce @@ -0,0 +1,30 @@ +clc
+IP=35; // Power developed by the engine in kW
+S=284; //Steam combustion in kg/h
+p2=0.14; //Condenser pressure in bar
+p1=15; //bar
+
+h1=2923.3; //kJ/kg
+s1=6.709; //kJ/kg K
+
+h_f=220; //kJ/kg
+h_fg=2376.6; //kJ/kg
+s_f=0.737; //kJ/kg K
+s_fg=7.296; //kJ/kg K
+
+x2=(s1-s_f)/s_fg;
+disp("(i) Final condition of steam =")
+disp(x2)
+
+h2=h_f+x2*h_fg;
+
+disp("(ii) Rankine efficiency=")
+n_rankine=(h1-h2)/(h1-h_f);
+disp(n_rankine)
+
+disp("(iii) Relative efficiency")
+n_thermal=IP/(S/3600)/(h1-h_f);
+
+n_relative=n_thermal/n_rankine;
+disp("relative efficiency=")
+disp(n_relative)
diff --git a/551/CH12/EX12.9/9.sce b/551/CH12/EX12.9/9.sce new file mode 100755 index 000000000..705398e26 --- /dev/null +++ b/551/CH12/EX12.9/9.sce @@ -0,0 +1,12 @@ +clc
+P=5000; //kW
+C=40000; //kJ/kg
+n_rankine=0.5;
+n_turbine=0.9;
+n_heat_transfer=0.85;
+n_combustion=0.98;
+
+m_f=P/n_turbine/(C*n_heat_transfer*n_combustion*n_rankine);
+disp("Fuel oil combustion=")
+disp(m_f)
+disp("kg/s")
diff --git a/551/CH13/EX13.1/1.sce b/551/CH13/EX13.1/1.sce new file mode 100755 index 000000000..450b4c5e2 --- /dev/null +++ b/551/CH13/EX13.1/1.sce @@ -0,0 +1,24 @@ +clc
+T1=671; //K
+T2=T1;
+T3=313; //K
+T4=T3;
+W=130; //kJ
+
+disp("(i) Engine thermal efficiency =")
+n_th=(T2-T3)/T2;
+disp(n_th)
+
+
+disp("(ii) Heat added =")
+Q=W/n_th;
+disp(Q)
+disp("kJ")
+
+
+disp("(iii) The entropy changes during heat rejection process")
+Q_rejected=Q-W;
+dS=Q_rejected/T3;
+disp("dS=")
+disp(dS)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH13/EX13.10/10.sce b/551/CH13/EX13.10/10.sce new file mode 100755 index 000000000..2c41c5b4a --- /dev/null +++ b/551/CH13/EX13.10/10.sce @@ -0,0 +1,44 @@ +clc
+r=6; //v1/v2=v4/v3=r
+p1=1; //bar
+T1=300; //K
+T3=1842; //K
+y=1.4;
+
+disp("(i) Temperature and pressure after the isentropic expansion")
+p2=p1*(r)^y;
+T2=T1*r^(y-1);
+p3=p2*(T3/T2);
+
+T4=T3/r^(y-1);
+disp("T4=")
+disp(T4)
+disp("K")
+
+p4=p3/(r)^(y);
+disp("p4 =")
+disp(p4)
+disp("bar")
+
+disp("(ii) Process required to complete the cycle")
+
+disp("Process required to complete the cycle is the constant pressure scavenging. The cycle is called Atkinson cycle")
+
+disp("(iii) Percentage improvement/increase in efficiency")
+p5=1; //bar
+T5=T3*(p5/p3)^((y-1)/y);
+
+n_otto=(1-1/r^(y-1))*100;
+disp("n_otto = ")
+disp(n_otto)
+disp("%")
+
+n_atkinson=(1-y*(T5-T1)/(T3-T2))*100;
+disp("n_atkinson=")
+disp(n_atkinson)
+disp("%")
+
+dn=n_atkinson - n_otto; //Improvement in efficiency
+disp("Improvement in efficiency =")
+disp(dn)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.11/11.sce b/551/CH13/EX13.11/11.sce new file mode 100755 index 000000000..c3fc6cf66 --- /dev/null +++ b/551/CH13/EX13.11/11.sce @@ -0,0 +1,25 @@ +clc
+p1=1; //bar
+T1=343; //K
+p2=7; //bar
+Qs=465; //kJ/kg of air
+cp=1; //kJ/kg K
+cv=0.706; //kJ/kg K
+y=1.41;
+
+disp("(i) Compression ratio of engine =")
+r=(p2/p1)^(1/y);
+disp(r)
+
+
+disp("(ii) Temperature at the end of compression =")
+T2=T1*(r)^(y-1);
+t2=T2-273;
+disp(t2)
+disp("0C")
+
+disp("(iii) Temperature at the end of heat addition =")
+T3=Qs/cv+T2;
+t3=T3-273;
+disp(t3)
+disp("0C")
diff --git a/551/CH13/EX13.12/12.sce b/551/CH13/EX13.12/12.sce new file mode 100755 index 000000000..2798c8b39 --- /dev/null +++ b/551/CH13/EX13.12/12.sce @@ -0,0 +1,29 @@ +clc
+
+y=1.4;
+R=0.287; //kJ/kg K
+T1=311; //K
+T3=2223; //K
+//p2/p1=15
+
+disp("(i) Compression ratio =")
+r=15^(1/1.4);
+disp(r)
+
+
+disp("(ii) Thermal efficiency =")
+n_th=1-1/r^(y-1);
+disp(n_th)
+
+disp("(iii) Work done")
+T2=T1*(r)^(y-1);
+T4=T3/r^(y-1);
+cv=R/(y-1);
+
+Q_supplied=cv*(T3-T2);
+Q_rejected=cv*(T4-T1);
+
+W=Q_supplied-Q_rejected;
+disp("Work done=")
+disp(W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH13/EX13.13/13.sce b/551/CH13/EX13.13/13.sce new file mode 100755 index 000000000..f941e0f20 --- /dev/null +++ b/551/CH13/EX13.13/13.sce @@ -0,0 +1,78 @@ +clc
+V1=0.45; //m^3
+p1=1; //bar
+T1=303; //K
+p2=11; //bar
+Qs=210; //kJ
+n=210; //number of working cycles/min
+R=287; //J/kg K
+cv=0.71; //kJ/kg K
+y=1.4;
+
+disp("(i) Pressures, temperatures and volumes at salient points")
+r=(p2/p1)^(1/y);
+
+T2=T1*(r)^(y-1);
+disp("T2=")
+disp(T2)
+disp("K")
+
+V2=T2/T1*p1/p2*V1;
+disp("V2=")
+disp(V2)
+disp("m^3")
+
+m=p1*10^5*V1/R/T1;
+T3=Qs/m/cv+T2;
+disp("T3=")
+disp(T3)
+disp("K")
+
+p3=T3/T2*p2;
+disp("p3=")
+disp(p3)
+disp("bar")
+
+V3=V2;
+disp("V3=")
+disp(V3)
+disp("m^3")
+
+p4=p3/r^y;
+disp("p4=")
+disp(p4)
+disp("bar")
+
+T4=T3/r^(y-1);
+disp("T4=")
+disp(T4)
+disp("K")
+
+V4=V1;
+disp("V4=")
+disp(V4)
+disp("m^3")
+
+
+disp("(ii) Percentage clearance =")
+%clearance=V2/(V1-V2)*100;
+disp(%clearance)
+disp("%")
+
+
+disp("(iii) Efficiency =")
+Qr=m*cv*(T4-T1);
+n_otto=(Qs-Qr)/Qs;
+disp(n_otto)
+
+
+disp("(iv) Mean effective pressure =")
+p_m=(Qs-Qr)/(V1-V2)/100; //bar
+disp(p_m)
+disp("bar")
+
+
+disp("(v) Power developed =")
+P=(Qs-Qr)*n/60;
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.14/14.sce b/551/CH13/EX13.14/14.sce new file mode 100755 index 000000000..cdcd079d5 --- /dev/null +++ b/551/CH13/EX13.14/14.sce @@ -0,0 +1,39 @@ +clc
+
+// W=Qs-Qr=cv*(T3-T2) - cv*(T4-T1)
+// T2=T1*(r^(y-1))
+// T3=T4*(r^(y-1))
+// W=cv*[T3-T1*r^(y-1) - T3/r^(y-1)+T1];
+// dW/dr=-T1*(y-1)*r^(y-2) - T3*(1-y)*r^(-y)=0
+
+//By solving this we get
+
+disp("r=(T3/T1)^(1/2/(y-1))")
+
+disp("(b)Change in efficiency")
+
+T3=1220; //K
+T1=310; //K
+
+// For air
+y=1.4;
+r1=(T3/T1)^(1/2/(y-1));
+n1=1-1/r1^(y-1); //air standard Efficiency
+disp("Air standard Efficiency =")
+disp(n1)
+
+//For helium
+cp=5.22; //kJ/kg K
+cv=3.13; //kJ/kg K
+y=cp/cv;
+r2=(T3/T1)^(1/2/(y-1));
+
+n2=1-1/r2^(y-1);
+disp("Air standard efficiency for helium =")
+disp(n2)
+
+change=n1-n2;
+disp("Change in efficiency=")
+disp(change)
+
+disp("Hence change in efficiency is nil")
\ No newline at end of file diff --git a/551/CH13/EX13.15/15.sce b/551/CH13/EX13.15/15.sce new file mode 100755 index 000000000..a7aeb5aad --- /dev/null +++ b/551/CH13/EX13.15/15.sce @@ -0,0 +1,32 @@ +clc
+// W=cv*[T3-T1*r^(y-1) - T3/r^(y-1)+T1]
+// r=(T3/T1)^(1/2/(y-1))
+// T2=T1*r^(y-1)
+// T4=T3/r^(y-1)
+
+// T2=T1*[(T3/T1)^(1/2/(y-1))]^(y-1)
+
+
+//T2=sqrt(T1*T3)
+
+//Similarly T4=T3/[(T3/T1)^(1/2/(y-1))]^(y-1)
+//T4=sqrt(T1*T3)
+
+disp("T2=T4=sqrt(T1*T3)")
+
+
+disp("(b) Power developed ")
+T1=310; //K
+T3=1450; //K
+m=0.38; //kg
+cv=0.71; //kJ/kg K
+
+T2=sqrt(T1*T3);
+T4=T2;
+
+W1=cv*[(T3-T2) - (T4-T1)]; //Work done
+W=m/60*W1; //Work done per second
+
+disp("Power =")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.17/17.sce b/551/CH13/EX13.17/17.sce new file mode 100755 index 000000000..ef5ba6174 --- /dev/null +++ b/551/CH13/EX13.17/17.sce @@ -0,0 +1,10 @@ +clc
+r=15;
+y=1.4;
+
+//V3-V2=0.06*(V1-V2)
+rho=1.84; //cut off ratio rho=V3/V2
+
+n_diesel=1-1/y/r^(y-1)*((rho^y-1)/(rho-1));
+disp("efficiency =")
+disp(n_diesel)
diff --git a/551/CH13/EX13.18/18.sce b/551/CH13/EX13.18/18.sce new file mode 100755 index 000000000..1fb6d1c68 --- /dev/null +++ b/551/CH13/EX13.18/18.sce @@ -0,0 +1,15 @@ +clc
+
+L=0.25; //m
+D=0.15; //m
+V2=0.0004; //m^3
+Vs=%pi/4*D^2*L;
+V_total=Vs+V2;
+y=1.4;
+V3=V2+5/100*Vs;
+rho=V3/V2;
+r=(Vs+V2)/V2; //V1=Vs+V2
+
+n_diesel=1-1/y/r^(y-1)*((rho^y-1)/(rho-1));
+disp("efficiency =")
+disp(n_diesel)
\ No newline at end of file diff --git a/551/CH13/EX13.19/19.sce b/551/CH13/EX13.19/19.sce new file mode 100755 index 000000000..25f36a543 --- /dev/null +++ b/551/CH13/EX13.19/19.sce @@ -0,0 +1,16 @@ +clc
+r=14; //let clearance volume be unity
+y=1.4;
+
+//When the fuel is cut-off at 5%
+rho1=5/100*(r-1)+1;
+n_diesel1=1-1/y/r^(y-1)*((rho1^y-1)/(rho1-1));
+
+//When the fuel is cut-off at 8%
+rho2=8/100*(r-1)+1;
+n_diesel2=1-1/y/r^(y-1)*((rho2^y-1)/(rho2-1));
+
+%loss=(n_diesel1-n_diesel2)*100;
+disp("percentage loss in efficiency due to delay in fuel cut off =")
+disp(%loss)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.2/2.sce b/551/CH13/EX13.2/2.sce new file mode 100755 index 000000000..dcd8dac1a --- /dev/null +++ b/551/CH13/EX13.2/2.sce @@ -0,0 +1,46 @@ +clc
+cv=0.721; //kJ/kg K
+cp=1.008; //kJ/kg K
+m=0.5; //kg
+n_th=0.5;
+Q_isothermal=40; //kJ
+p1=7*10^5; //Pa
+V1=0.12; //m^3
+R=287; //J/kg K
+
+disp("(i) The maximum and minimum temperatures")
+T1=p1*V1/m/R;
+disp("Maximun temperature =")
+disp(T1)
+disp("K")
+
+T2=(1-n_th)*T1;
+disp("Minimum temperature =")
+disp(T2)
+disp("K")
+
+
+disp("(ii) The volume at the end of isothermal expansion =")
+V2=V1*%e^(Q_isothermal*10^3/m/R/T1);
+disp(V2)
+disp("m^3")
+
+
+disp("(iii) The heat transfer for each of the four processes")
+
+Q1=Q_isothermal;
+disp("Isothermal expansion")
+disp(Q1)
+disp("kJ")
+
+Q2=0;
+disp("Adiabatic reversible expansion")
+disp(Q2)
+
+Q3=-Q_isothermal;
+disp("Isothermal compression")
+disp(Q3)
+
+Q4=0;
+disp("Adiabatic reversible compression")
+disp(Q4)
\ No newline at end of file diff --git a/551/CH13/EX13.20/20.sce b/551/CH13/EX13.20/20.sce new file mode 100755 index 000000000..9e2ade33a --- /dev/null +++ b/551/CH13/EX13.20/20.sce @@ -0,0 +1,15 @@ +clc
+
+pm=7.5; //bar
+r=12.5;
+p1=1; //bar
+y=1.4;
+
+// pm = p1*r^y*[y*(rho-1) - r^(1-y)*(rho^y-1)]/(y-1)/(r-1)
+//Solving above equation we get
+rho=2.24;
+
+%cutoff=(rho-1)/(r-1)*100;
+disp("%cutoff=")
+disp(%cutoff)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.21/21.sce b/551/CH13/EX13.21/21.sce new file mode 100755 index 000000000..3afd2c579 --- /dev/null +++ b/551/CH13/EX13.21/21.sce @@ -0,0 +1,81 @@ +clc
+D=0.2; //m
+L=0.3; //m
+p1=1; //bar
+T1=300; //K
+R=287;
+r=15;
+y=1.4;
+
+disp("(i) Pressures and temperatures at salient points")
+Vs=%pi/4*D^2*L;
+
+V1=r/(r-1)*Vs;
+disp("V1=")
+disp(V1)
+disp("m^3")
+
+m=p1*10^5*V1/R/T1;
+
+p2=p1*r^y;
+disp("p2=")
+disp(p2)
+disp("bar")
+
+T2=T1*r^(y-1);
+disp("T2=")
+disp(T2)
+disp("K")
+
+V2=Vs/(r-1);
+disp("V2=")
+disp(V2)
+disp("m^3")
+
+rho=8/100*(r-1) + 1;
+V3=rho*V2;
+disp("V3=")
+disp(V3)
+disp("m^3")
+
+T3=T2*V3/V2;
+disp("T3=")
+disp(T3)
+disp("K")
+
+p3=p2;
+disp("p3=")
+disp(p3)
+disp("bar")
+
+p4=p3*(rho/r)^y;
+disp("p4=")
+disp(p4)
+disp("bar")
+
+T4=T3*(rho/r)^(y-1);
+disp("T4=")
+disp(T4)
+disp("K")
+
+V4=V1;
+disp("V4=")
+disp(V4)
+disp("m^3")
+
+disp("(ii) Theoretical air standard efficiency =")
+n_diesel=1-1/y/r^(y-1)*((rho^y-1)/(rho-1));
+disp("efficiency =")
+disp(n_diesel)
+
+
+disp("(iii) Mean effective pressure =")
+pm=(p1*r^y*(y*(rho-1) - r^(1-y)*(rho^y-1)))/(y-1)/(r-1);
+disp(pm)
+disp("bar")
+
+disp("(iv) Power of the engine =")
+n=380; //number of cycles per min
+P=n/60*pm*Vs*100; //kW
+disp(P)
+disp("kW")
diff --git a/551/CH13/EX13.22/22.sce b/551/CH13/EX13.22/22.sce new file mode 100755 index 000000000..40d145d54 --- /dev/null +++ b/551/CH13/EX13.22/22.sce @@ -0,0 +1,46 @@ +clc
+r1=15.3; //V1/V2
+r2=7.5; //V4/V3
+p1=1; //bar
+T1=300; //K
+n_mech=0.8;
+C=42000; //kJ/kg
+y=1.4;
+R=287;
+cp=1.005;
+cv=0.718;
+V2=1; ////Assuming V2=1 m^3
+
+T2=T1*r1^(y-1);
+p2=p1*r1^y;
+T3=r1/r2*T2;
+m=p2*10^5*V2/R/T2;
+T4=T3/r2^(y-1);
+
+Q_added=m*cp*(T3-T2);
+Q_rejected=m*cv*(T4-T1);
+W=Q_added-Q_rejected;
+
+pm=W/(r1-1)/V2/100;
+disp("Mean effective pressure =")
+disp(pm)
+disp("bar")
+
+ratio=p2/pm;
+disp("Ratio of maximum pressure to mean effective pressure =")
+disp(ratio)
+
+n_cycle=W/Q_added;
+disp("Cycle efficiency =")
+disp(n_cycle)
+
+n_thI=0.5;
+n_cycle1=n_thI*n_cycle;
+
+n_thB=n_mech*n_cycle1;
+
+BP=1;
+mf=BP/C/n_thB*3600;
+disp("Fuel consumption per kWh =")
+disp(mf)
+disp("kg/kWh")
\ No newline at end of file diff --git a/551/CH13/EX13.23/23.sce b/551/CH13/EX13.23/23.sce new file mode 100755 index 000000000..20d2f678f --- /dev/null +++ b/551/CH13/EX13.23/23.sce @@ -0,0 +1,19 @@ +clc
+Vs=0.0053; //m^3
+Vc=0.00035; //m^3
+V3=Vc;
+V2=V3;
+p3=65; //bar
+p4=65; //bar
+T1=353; //K
+p1=0.9; //bar
+y=1.4;
+
+r=(Vs+Vc)/Vc;
+rho=(5/100*Vs+V3)/V3;
+p2=p1*(r)^y;
+B=p3/p2;
+
+n_dual=1-1/r^(y-1)*[(B*rho^y-1)/((B-1)+B*y*(rho-1))];
+disp("Efficiency of the cycle =")
+disp(n_dual)
\ No newline at end of file diff --git a/551/CH13/EX13.24/24.sce b/551/CH13/EX13.24/24.sce new file mode 100755 index 000000000..71a4283dd --- /dev/null +++ b/551/CH13/EX13.24/24.sce @@ -0,0 +1,9 @@ +clc
+r=14;
+B=1.4;
+rho=6/100*(r-1) + 1;
+y=1.4;
+
+n_dual=1-1/r^(y-1)*[(B*rho^y-1)/((B-1)+B*y*(rho-1))]
+disp("Efficiency of the cycle =")
+disp(n_dual)
\ No newline at end of file diff --git a/551/CH13/EX13.25/25.sce b/551/CH13/EX13.25/25.sce new file mode 100755 index 000000000..026f5cb9a --- /dev/null +++ b/551/CH13/EX13.25/25.sce @@ -0,0 +1,46 @@ +clc
+D=0.25; //m
+r=9;
+L=0.3; //m
+cv=0.71; //kJ/kg K
+cp=1; //kJ/kg K
+p1=1; //bar
+T1=303; //K
+p3=60; //bar
+p4=p3;
+n=3; //number of working cycles/ sec
+y=1.4;
+R=287;
+
+disp("(i) Air standard efficiency")
+Vs=%pi/4*D^2*L;
+
+Vc=Vs/(r-1);
+V1=Vs+Vc;
+p2=p1*(r)^y;
+T2=T1*r^(y-1);
+T3=T2*p3/p2;
+rho=4/100*(r-1)+1;
+T4=T3*rho;
+
+T5=T4*(rho/r)^(y-1);
+p5=p4*(r/rho)^(y);
+
+Qs=cv*(T3-T2)+cp*(T4-T3)
+
+Qr=cv*(T5-T1);
+
+n_airstandard=(Qs-Qr)/Qs;
+disp("efficiency =")
+disp(n_airstandard)
+
+
+disp("(ii) Power developed by the engine")
+m=p1*10^5*V1/R/T1;
+
+W=m*(Qs-Qr);
+
+P=W*n;
+disp("P=")
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.26/26.sce b/551/CH13/EX13.26/26.sce new file mode 100755 index 000000000..bcf833d65 --- /dev/null +++ b/551/CH13/EX13.26/26.sce @@ -0,0 +1,66 @@ +clc
+p1=1; //bar
+T1=363; //K
+r=9;
+p3=68; //bar
+p4=68; //bar
+Q=1750; //kJ/kg
+y=1.4;
+cv=0.71;
+cp=1.0;
+
+disp("(i) Pressures and temperatures at salient points")
+p2=p1*(r)^y;
+disp("p2=")
+disp(p2)
+disp("bar")
+
+T2=T1*r^(y-1);
+disp("T2=")
+disp(T2)
+disp("K")
+
+disp("p3=")
+disp(p3)
+disp("bar")
+
+disp("p4=")
+disp(p4)
+disp("bar")
+
+T3=T2*(p3/p2);
+disp("T3=")
+disp(T3)
+disp("K")
+
+Q1=cv*(T3-T2); //heat added at constant volume
+Q2=Q-Q1; //heat added at constant pressure
+
+T4=Q2/cp+T3;
+disp("T4=")
+disp(T4)
+disp("K")
+
+rho=T4/T3; //V4/V3=T4/T3
+
+p5=p4*(rho/r)^y;
+disp("p5=")
+disp(p5)
+disp("bar")
+
+T5=T4*(rho/r)^(y-1);
+disp("T5=")
+disp(T5)
+disp("K")
+
+
+disp("(ii) Air standard efficiency =")
+Qr=cv*(T5-T1);
+n_airstandard=(Q-Qr)/Q;
+disp(n_airstandard)
+
+
+disp("(iii) Mean effective pressure =")
+pm=1/(r-1)*(p3*(rho-1) + (p4*rho-p5*r)/(y-1) - (p2-p1*r)/(y-1));
+disp(pm)
+disp("bar")
diff --git a/551/CH13/EX13.27/27.sce b/551/CH13/EX13.27/27.sce new file mode 100755 index 000000000..edbbc6e33 --- /dev/null +++ b/551/CH13/EX13.27/27.sce @@ -0,0 +1,32 @@ +clc
+T1=300; //K
+r=15;
+y=1.4;
+//p3/p1=70
+
+T2=T1*(r)^(y-1);
+
+//p2/p1=r^y
+//p2=44.3*p1
+
+T3=1400; //K; T3=T2*p3/p2
+
+T4=T3 + (T3-T2)/y;
+
+//v1/v3=15
+//v4=0.084*v1
+//v5=v1
+//T5=T4*(v5/v1)^(y-1)
+T5=656.9; //K
+
+n_airstandard=1-(T5-T1)/((T3-T2) + y*(T4-T3));
+disp("Efficiency =")
+disp(n_airstandard)
+
+disp("Reasons for actual thermal efficiency being different from the theoretical value :")
+
+disp("1. In theoretical cycle working substance is taken air whereas in actual cycle air with fuel acts as working substance")
+
+disp("2. The fuel combustion phenomenon and associated problems like dissociation of gases, dilution of charge during suction stroke, etc. have not been taken into account")
+
+disp("3. Effect of variable specific heat, heat loss through cylinder walls, inlet and exhaust velocities of air/gas etc. have not been taken into account.")
\ No newline at end of file diff --git a/551/CH13/EX13.28/28.sce b/551/CH13/EX13.28/28.sce new file mode 100755 index 000000000..ea5a48a84 --- /dev/null +++ b/551/CH13/EX13.28/28.sce @@ -0,0 +1,41 @@ +clc
+T1=373; //K
+p1=1; //bar
+p3=65; //bar
+p4=p3;
+Vs=0.0085; //m^3
+ratio=21; //Air fuel ratio
+r=15;
+C=43890; //kJ/kg
+cp=1;
+cv=0.71;
+V2=0.0006; //m^3
+V1=0.009; //m^3
+y=1.41;
+V5=V1;
+V3=V2;
+R=287;
+
+p2=p1*(r)^y;
+T2=T1*r^(y-1);
+T3=T2*p3/p2;
+m=p1*10^5*V1/R/T1;
+
+Q1=m*cv*(T3-T2); //Heat added during constant volume process 2-3
+amt=Q1/C; //Amount of fuel added during the constant volume process 2-3
+total=m/ratio; //Total amount of fuel added
+quantity=total-amt; //Quantity of fuel added during the process 3-4
+
+Q2=quantity*C; //Heat added during constant pressure process
+
+T4=Q2/(m+total)/cp+T3;
+V4=V3*T4/T3;
+T5=T4*(V4/V5)^(y-1);
+
+Q3=(m+total)*cv*(T5-T1); //Heat rejected during constant volume process 5-1
+
+W=(Q1+Q2) - Q3;
+
+n_th=W/(Q1+Q2);
+disp("Thermal efficiency =")
+disp(n_th)
\ No newline at end of file diff --git a/551/CH13/EX13.29/29.sce b/551/CH13/EX13.29/29.sce new file mode 100755 index 000000000..69fc24891 --- /dev/null +++ b/551/CH13/EX13.29/29.sce @@ -0,0 +1,83 @@ +clc
+T1=303; //K
+p1=1; //bar
+rc=9;
+re=5;
+n=1.25;
+D=0.25; //m
+L=0.4; //m
+R=287;
+cv=0.71;
+cp=1;
+num=8; //no. 0f cycles/sec
+
+disp("(i) Pressure and temperatures at all salient points =")
+p2=p1*(rc)^n;
+disp("p2=")
+disp(p2)
+disp("bar")
+
+T2=T1*(rc)^(n-1);
+disp("T2=")
+disp(T2)
+disp("K")
+
+//T4=1.8*T3
+//Heat liberated at constant pressure= 2 × heat liberated at constant volume
+//cp*(T4-T3)=2*cv*(T3-T2)
+//T4/T3=1.8
+
+rho=rc/re;
+T3=1201.9; //K
+disp("T3=")
+disp(T3)
+disp("K")
+
+p3=p2*T3/T2;
+disp("p3=")
+disp(p3)
+disp("bar")
+
+p4=p3;
+disp("p4=")
+disp(p4)
+disp("bar")
+
+T4=1.8*T3;
+disp("T4=")
+disp(T4)
+disp("K")
+
+p5=p4*(1/re)^(n);
+disp("p5=")
+disp(p5)
+disp("bar")
+
+T5=T4*(1/re)^(n-1)
+disp("T5=")
+disp(T5)
+disp("K")
+
+
+disp("(ii) Mean effective pressure = ")
+pm=1/(rc-1)*[p3*(rho-1)+(p4*rho-p5*rc)/(n-1)-(p2-p1*rc)/(n-1)];
+disp(pm)
+disp("bar")
+
+disp("(iii) Efficiency of the cycle")
+Vs=%pi/4*D^2*L;
+W=pm*10^5*Vs/1000;
+
+V1=rc/(rc-1)*Vs
+m=p1*10^5*V1/R/T1;
+Q=m*(cv*(T3-T2) + cp*(T4-T3));
+
+Efficiency=W/Q;
+disp("Efficiency =")
+disp(Efficiency)
+
+
+disp("(iv) Power of the engine =")
+P=W*num;
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.3/3.sce b/551/CH13/EX13.3/3.sce new file mode 100755 index 000000000..a320b137f --- /dev/null +++ b/551/CH13/EX13.3/3.sce @@ -0,0 +1,63 @@ +clc
+p1=18*10^5; //Pa
+T1=683; //K
+T2=T1;
+r1=6; //ratio V4/V1; Isentropic compression
+r2=1.5; //ratio V2/V1; Isothermal expansion
+y=1.4;
+V1=0.18; //m^3
+
+disp("(i) Temperatures and pressures at the main points in the cycle")
+
+T4=T1/(r1)^(y-1);
+disp("T4=")
+disp(T4)
+disp("K")
+
+T3=T4;
+disp("T3=")
+disp(T3)
+disp("K")
+
+p2=p1/r2;
+disp("p2=")
+disp(p2/10^5)
+disp("bar")
+
+p3=p2/(r1)^y;
+disp("p3=")
+disp(p3/10^5)
+disp("bar")
+
+p4=p1/(r1)^y;
+disp("p4=")
+disp(p4/10^5)
+disp("bar")
+
+
+disp("(ii) Change in entropy =")
+dS=p1*V1/T1/10^3*log(r2);
+disp(dS)
+disp("kJ/K")
+
+
+disp("(iii) Mean thermal efficiency of the cycle")
+Qs=T1*(dS);
+Qr=T4*(dS);
+
+n=1-Qr/Qs;
+disp("n=")
+disp(n)
+
+
+disp("(iv) Mean effective pressure of the cycle =")
+pm=(Qs-Qr)/8/V1/100; //bar
+disp(pm)
+disp("bar")
+
+
+n=210; //cycles per minute
+disp("(v) Power of the engine =")
+P=(Qs-Qr)*n/60; //kW
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.30/30.sce b/551/CH13/EX13.30/30.sce new file mode 100755 index 000000000..f8823db0f --- /dev/null +++ b/551/CH13/EX13.30/30.sce @@ -0,0 +1,84 @@ +clc
+v=10:1:100;
+function p=f(v)
+ p=1/v^1.4;
+endfunction
+plot(v,f)
+
+v=[10 20]
+p=[f(10) f(10)]
+plot(v,p,'r')
+
+v=20:1:100;
+function p=fa(v)
+ p=2.6515/v^1.4;
+endfunction
+plot(v,fa,'g')
+
+v=[100 100]
+p=[f(100) fa(100)]
+plot(v,p,'--p')
+
+v=[15 15]
+p=[f(15) 0.040]
+plot(v,p,'--')
+
+v=[20 20]
+p=[f(20) 0.040]
+plot(v,p,'--r')
+
+xtitle("p-v diagram", "v", "p")
+legend("1-2b","2b-3", "3-4", "4-1", "2a-3a", "2-3")
+
+//The air-standard Otto, Dual and Diesel cycles are drawn on common p-v and T-s diagrams for the same maximum pressure and maximum temperature, for the purpose of comparison.
+// Otto 1-2-3-4-1
+// Dual 1-2a-3a-3-4-1
+// Diesel 1-2b-3-4-1
+
+
+xset('window', 1)
+
+s=10:1:50;
+function T=fb(s)
+ T=s^2
+endfunction
+plot(s,fb)
+
+s=10:1:50;
+function T=fc(s)
+ T=(s+30)^2
+endfunction
+plot(s,fc,'r')
+
+s=[12 12];
+T=[fb(12) fc(12)];
+plot(s,T,'--p')
+
+s=[45 45];
+T=[fb(45) fc(45)]
+plot(s,T,'m')
+
+s=10:1:27;
+T=5*(s)^2;
+plot(s,T,'g')
+
+s=10:1:20;
+T=7*s^2;
+plot(s,T,'--r')
+
+xtitle("T-s diagram", "s", "T")
+legend("1-4", "2b-3", "1-2b", "3-4", "2-3", "2a-3a")
+
+// The construction of cycles on T-s diagram proves that for the given conditions the heat rejected is same for all the three cycles (area under process line 4-1).
+// η=1-(Heat rejected)/(Heat supplied)=1-constant/Qs
+
+// The cycle with greater heat addition will be more efficient.
+// From the T-s diagram
+
+// Qs(diesel) = Area under 2b-3
+// Qs(dual) = Area under 2a-3a-3
+// Qs(otto) = Area under 2-3.
+
+// Qs(diesel) > Qs(dual) > Qs(otto)
+
+disp("Thus, ηdiesel > ηdual > ηotto")
\ No newline at end of file diff --git a/551/CH13/EX13.31/31.sce b/551/CH13/EX13.31/31.sce new file mode 100755 index 000000000..9fac4a29d --- /dev/null +++ b/551/CH13/EX13.31/31.sce @@ -0,0 +1,27 @@ +clc
+cp=0.92;
+cv=0.75;
+y=1.22; //y=cp/cv
+p1=1; //bar
+p2=p1;
+p3=4; //bar
+p4=16; //bar
+T2=300; //K
+
+T3=T2*(p3/p2)^((y-1)/y);
+T4=p4/p3*T3;
+T1=T4/(p4/p1)^((y-1)/y);
+
+disp("(i) Work done per kg of gas ")
+Q_supplied=cv*(T4-T3);
+Q_rejected=cp*(T1-T2);
+
+W=Q_supplied-Q_rejected;
+disp("W=")
+disp(W)
+disp("kJ/kg")
+
+
+disp("(ii) Efficiency of the cycle =")
+n=W/Q_supplied;
+disp(n)
\ No newline at end of file diff --git a/551/CH13/EX13.32/32.sce b/551/CH13/EX13.32/32.sce new file mode 100755 index 000000000..a2a9536c3 --- /dev/null +++ b/551/CH13/EX13.32/32.sce @@ -0,0 +1,25 @@ +clc
+p1=101.325; //kPa
+T1=300; //K
+rp=6;
+y=1.4;
+
+T2=T1*rp^((y-1)/y);
+
+//T3/T4=rp^((y-1)/y)
+//T4=T3/1.668
+
+//W_T=2.5*W_C
+
+T3=2.5*(T2-T1)/(1-1/1.668);
+disp("(i) Maximum temperature in the cycle =")
+disp(T3)
+disp("K")
+
+
+disp("(ii) Cycle efficiency")
+T4=T3/1.668;
+
+n_cycle=((T3-T4) - (T2-T1))/(T3-T2);
+disp(" Cycle efficiency =")
+disp(n_cycle)
\ No newline at end of file diff --git a/551/CH13/EX13.33/33.sce b/551/CH13/EX13.33/33.sce new file mode 100755 index 000000000..01a6ec8fa --- /dev/null +++ b/551/CH13/EX13.33/33.sce @@ -0,0 +1,40 @@ +clc
+p1=1; //bar
+p2=5; //bar
+T3=1000; //K
+cp=1.0425; //kJ/kg K
+cv=0.7662; //kJ/kg K
+y=cp/cv;
+
+disp("(i)Temperature entropy diagram")
+
+s=10:1:50;
+function T=fb(s)
+ T=s^2
+endfunction
+plot(s,fb,'--')
+
+s=10:1:50;
+function T=fc(s)
+ T=(s+30)^2
+endfunction
+plot(s,fc,'r')
+
+s=[12 12];
+T=[fb(12) fc(12)];
+plot(s,T,'m')
+
+s=[45 45];
+T=[fb(45) fc(45)]
+plot(s,T,'g')
+
+
+xtitle("T-s diagram", "s", "T")
+legend("p1=1 bar", "p2=5 bar", "1-2", "3-4")
+
+disp("(ii) Power required =")
+T4=T3*(p1/p2)^((y-1)/y);
+P=cp*(T3-T4);
+disp("P=")
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.34/34.sce b/551/CH13/EX13.34/34.sce new file mode 100755 index 000000000..68cc266ce --- /dev/null +++ b/551/CH13/EX13.34/34.sce @@ -0,0 +1,17 @@ +clc
+m=0.1; //kg/s
+p1=1; //bar
+T4=285; //K
+p2=4; //bar
+cp=1; //kJ/kg K
+y=1.4;
+
+T3=T4*(p2/p1)^((y-1)/y);
+disp("Temperature at turbine inlet =")
+disp(T3)
+disp("K")
+
+P=m*cp*(T3-T4);
+disp("Power developed =")
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.35/35.sce b/551/CH13/EX13.35/35.sce new file mode 100755 index 000000000..4777574cb --- /dev/null +++ b/551/CH13/EX13.35/35.sce @@ -0,0 +1,34 @@ +clc
+y=1.4;
+cp=1.005; //kJ/kg K
+p1=1; //bar
+T1=293; //K
+p2=3.5; //bar
+T3=873; //K
+rp=p2/p1;
+
+disp("(i) Efficiency of the cycle =")
+n_cycle=1-1/rp^((y-1)/y);
+disp(n_cycle)
+
+
+disp("(ii) Heat supplied to air =")
+T2=T1*(p2/p1)^((y-1)/y);
+Q1=cp*(T3-T2);
+disp(Q1)
+disp("kJ/kg")
+
+disp("(iii) Work available at the shaft =")
+W=n_cycle*Q1;
+disp(W)
+disp("kJ/kg")
+
+disp("(iv) Heat rejected in the cooler =")
+Q2=Q1-W;
+disp(Q2)
+disp("kJ/kg")
+
+disp("(v) Temperature of air leaving the turbine =")
+T4=T3/rp^((y-1)/y);
+disp(T4)
+disp("K")
\ No newline at end of file diff --git a/551/CH13/EX13.36/36.sce b/551/CH13/EX13.36/36.sce new file mode 100755 index 000000000..fa9d3e541 --- /dev/null +++ b/551/CH13/EX13.36/36.sce @@ -0,0 +1,21 @@ +clc
+T1=303; //K
+T3=1073; //K
+C=45000; //kJ/kg
+cp=1; //kJ/kg K
+y=1.4;
+
+T2=sqrt(T1*T3);
+T4=T2;
+
+//W_turbine-W_compressor=m_f*C*n=100;
+
+m_f=100/C/(1-(T4-T1)/(T3-T2));
+disp("m_f=")
+disp(m_f)
+disp("kg/s")
+
+m_a=(100-m_f*(T3-T4))/(T3-T4-T2+T1);
+disp("m_a=")
+disp(m_a)
+disp("kg/s")
\ No newline at end of file diff --git a/551/CH13/EX13.37/37.sce b/551/CH13/EX13.37/37.sce new file mode 100755 index 000000000..bfa324954 --- /dev/null +++ b/551/CH13/EX13.37/37.sce @@ -0,0 +1,44 @@ +clc
+T1=300; //K
+p1=1; //bar
+rp=6.25;
+T3=1073; //K
+n_comp=0.8;
+n_turbine=0.8;
+cp=1.005; //kJ/kg K
+y=1.4;
+
+T2=T1*(rp)^((y-1)/y);
+
+//Let T2'=T2a
+T2a=(T2-T1)/n_comp + T1;
+
+W_comp=cp*(T2a-T1);
+disp("Compressor work =")
+disp(W_comp)
+disp("kJ/kg")
+
+T4=T3/rp^((y-1)/y);
+T4a=T3-n_turbine*(T3-T4);
+
+W_turbine=cp*(T3-T4a);
+disp("Turbine work =")
+disp(W_turbine)
+disp("kJ/kg")
+
+Q_s=cp*(T3-T2a);
+disp("Heat supplied =")
+disp(Q_s)
+disp("kJ/kg")
+
+W_net=W_turbine - W_comp;
+
+n_cycle=W_net/Q_s*100;
+disp("n_cycle")
+disp(n_cycle)
+disp("%")
+
+t4a=T4a-273;
+disp("Turbine exhaust temperature =")
+disp(t4a)
+disp("0C")
\ No newline at end of file diff --git a/551/CH13/EX13.38/38.sce b/551/CH13/EX13.38/38.sce new file mode 100755 index 000000000..761e53e8b --- /dev/null +++ b/551/CH13/EX13.38/38.sce @@ -0,0 +1,19 @@ +clc
+n_turbine=0.85;
+n_compressor=0.80;
+T3=1148; //K
+T1=300; //K
+cp=1; //kJ/kg K
+y=1.4;
+p1=1; //bar
+p2=4; //bar
+C=42000; //kJ/kg K
+n_cc=0.90;
+
+T2=T1*(p2/p1)^((y-1)/y);
+
+T2a=(T2-T1)/n_compressor + T1;
+
+ratio=0.9*C/cp/(T3-T2a) - 1; //ratio=ma/mf
+disp("A/F ratio =")
+disp(ratio)
\ No newline at end of file diff --git a/551/CH13/EX13.39/39.sce b/551/CH13/EX13.39/39.sce new file mode 100755 index 000000000..95ecf0c81 --- /dev/null +++ b/551/CH13/EX13.39/39.sce @@ -0,0 +1,30 @@ +clc
+cp=1.005; //kJ/kg K
+y1=1.4;
+y2=1.333;
+p1=1; //bar
+p4=p1;
+T1=300; //K
+p2=6.2; //bar
+p3=p2;
+n_compressor=0.88;
+C=44186; //kJ/kg
+ratio=0.017; //Fuel-air ratio; kJ/kg of air
+n_turbine=0.9; //
+cpg=1.147;
+
+T2=T1*(p2/p1)^((y1-1)/y1);
+T2a=(T2-T1)/n_compressor + T1; //T2'
+
+T3=ratio*C/(1+ratio)/cp + T2a;
+T4=T3*(p4/p3)^((y2-1)/y2);
+T4a=T3-n_turbine*(T3-T4);
+W_compressor=cp*(T2a-T1);
+W_turbine=cpg*(T3-T4a);
+W_net=W_turbine-W_compressor;
+Qs=ratio*C;
+
+n_th=W_net/Qs*100;
+disp("Thermal efficiency =")
+disp(n_th)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.4/4.sce b/551/CH13/EX13.4/4.sce new file mode 100755 index 000000000..9ca5049cd --- /dev/null +++ b/551/CH13/EX13.4/4.sce @@ -0,0 +1,21 @@ +clc
+
+// First case
+//(T1-T2)/T1=1/6
+//T1=1.2*T2
+
+
+// Second case
+//(T1-(T2-(70+273)))/T3=1/3
+
+T2=1029/0.6;
+T1=1.2*T2;
+
+disp("Temperature of the source =")
+disp(T1)
+disp("K")
+
+
+disp("Temperature of the sink=")
+disp(T2)
+disp("K")
\ No newline at end of file diff --git a/551/CH13/EX13.40/40.sce b/551/CH13/EX13.40/40.sce new file mode 100755 index 000000000..564dc84c9 --- /dev/null +++ b/551/CH13/EX13.40/40.sce @@ -0,0 +1,36 @@ +clc
+cp=1; //kJ/kg K
+y=1.4;
+C=41800; //kJ/kg
+p1=1; //bar
+T1=293; //K
+p2=4; //bar
+p4=p1;
+p3=p2;
+n_compressor=0.80;
+n_turbine=0.85;
+ratio=90; //Air-Fuel ratio
+m_a=3; //kg/s
+
+disp("(i)Power developed ")
+T2=T1*(p2/p1)^((y-1)/y);
+T2a=(T2-T1)/n_compressor + T1;
+T3=C/(1+ratio)/cp + T2a;
+T4=T3*(p4/p3)^((y-1)/y);
+T4a=T3-n_turbine*(T3-T4);
+
+W_turbine=(ratio+1)/ratio*cp*(T3-T4a);
+W_compressor=cp*(T2a-T1);
+W_net=W_turbine-W_compressor;
+Qs=1/ratio*C;
+
+P=m_a*W_net;
+disp("Power=")
+disp(P)
+disp("kW/kg of air")
+
+
+disp("(ii) Thermal efficiency of cycle =")
+n_thermal=W_net/Qs;
+disp(n_thermal)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.41/41.sce b/551/CH13/EX13.41/41.sce new file mode 100755 index 000000000..84555c48d --- /dev/null +++ b/551/CH13/EX13.41/41.sce @@ -0,0 +1,25 @@ +clc
+T1=288; //K
+T3=883; //K
+rp=6; //rp=p2/p1
+n_compressor=0.80;
+n_turbine=0.82;
+m_a=16; //kg/s
+cp1=1.005; //kJ/kg K, For compression process
+y1=1.4; // For compression process
+cp2=1.11; //kJ/kg K
+y2=1.333;
+
+T2=T1*(rp)^((y1-1)/y1);
+T2a=(T2-T1)/n_compressor + T1;
+T4=T3/rp^((y2-1)/y2);
+T4a=T3-n_turbine*(T3-T4);
+
+W_compressor=cp1*(T2a-T1);
+W_turbine=cp2*(T3-T4a);
+W_net=W_turbine-W_compressor;
+
+Power=m_a*W_net;
+disp("Power =")
+disp(Power)
+disp("kW")
\ No newline at end of file diff --git a/551/CH13/EX13.42/42.sce b/551/CH13/EX13.42/42.sce new file mode 100755 index 000000000..ac605c087 --- /dev/null +++ b/551/CH13/EX13.42/42.sce @@ -0,0 +1,17 @@ +clc
+cp=1.11;
+T3=883; //K
+T2a=529; //K
+W_turbine=290.4; //kJ/kg
+W_net=48.2; //kJ/kg
+
+Qs=cp*(T3-T2a);
+
+n_thermal=W_net/Qs*100;
+disp("Thermal efficiency =")
+disp(n_thermal)
+disp("%")
+
+W_ratio=W_net/W_turbine; //Work ratio=net work output/Gross work output
+disp("Work ratio =")
+disp(W_ratio)
\ No newline at end of file diff --git a/551/CH13/EX13.43/43.sce b/551/CH13/EX13.43/43.sce new file mode 100755 index 000000000..144665e27 --- /dev/null +++ b/551/CH13/EX13.43/43.sce @@ -0,0 +1,40 @@ +clc
+p1=1; //bar
+p2=5; //bar
+p3=4.9; //bar
+p4=1; //bar
+T1=293; //K
+T3=953; //K
+n_compressor=0.85;
+n_turbine=0.80;
+n_combustion=0.85;
+y=1.4;
+cp=1.024; //kJ/kg K
+P=1065; //kW
+
+disp("(i) The quantity of air circulation")
+T2=T1*(p2/p1)^((y-1)/y);
+T2a=(T2-T1)/n_compressor + T1;
+T4=T3*(p4/p3)^((y-1)/y);
+T4a=T3-n_turbine*(T3-T4);
+
+W_compressor=cp*(T2a-T1);
+W_turbine=cp*(T3-T4a);
+W_net=W_turbine-W_compressor;
+
+m_a=P/W_net;
+disp("m_a =")
+disp(m_a)
+disp("kg")
+
+
+disp("(ii) Heat supplied per kg of air circulation =")
+Qs=cp*(T3-T2a)/n_combustion;
+disp(Qs)
+disp("kJ/kg")
+
+
+disp("(iii) Thermal efficiency of the cycle =")
+n_thermal=W_net/Qs*100;
+disp(n_thermal)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.44/44.sce b/551/CH13/EX13.44/44.sce new file mode 100755 index 000000000..89a9f4fe8 --- /dev/null +++ b/551/CH13/EX13.44/44.sce @@ -0,0 +1,25 @@ +clc
+m_a=20; //kg/s
+T1=300; //K
+T3=1000; //K
+rp=4; //rp=p2/p1
+cp=1; //kJ/kg K
+y=1.4;
+
+T2=T1*(rp)^((y-1)/y);
+T4=T3-T2+T1;
+
+//p5/p4=(p5/p3)*(p3/p4)
+//let p3/p4=r1
+r1=(T3/T4)^(y/(y-1));
+
+//r2=p5/p4;
+r2=1/4*r1;
+P_ratio=1/r2; //Pressure ratio of low pressure turbine
+disp("Pressure ratio of low pressure turbine =")
+disp(P_ratio)
+
+T5=T4/(P_ratio)^((y-1)/y);
+disp("Temperature of the exhaust from the unit =")
+disp(T5)
+disp("K")
\ No newline at end of file diff --git a/551/CH13/EX13.45/45.sce b/551/CH13/EX13.45/45.sce new file mode 100755 index 000000000..f40ffe5bd --- /dev/null +++ b/551/CH13/EX13.45/45.sce @@ -0,0 +1,57 @@ +clc
+T1=288; //K
+p1=1.01; //bar
+rp=7;
+p2=rp*p1;
+p3=p2;
+p5=p1;
+n_compressor=0.82;
+n_turbine=0.85;
+n_turbine=0.85;
+T3=883; //K
+cpa=1.005;
+cpg=1.15;
+y1=1.4;
+y2=1.33;
+
+disp("(i) Pressure and temperature of the gases entering the power turbine =")
+
+T2=T1*rp^((y1-1)/y1);
+T2a=(T2-T1)/n_compressor + T1;
+
+W_compressor=cpa*(T2a-T1);
+
+T4a=(cpg*T3-W_compressor)/cpg;
+disp("Temperature of gases entering the power turbine =")
+disp(T4a)
+disp("K")
+
+T4=T3-(T3-T4a)/n_turbine;
+
+p4=p3/(T3/T4)^(y2/(y2-1));
+disp("Pressure of gases entering the power turbine =")
+disp(p4)
+disp("bar")
+
+
+disp("(ii) Net power developed per kg/s mass flow")
+T5=T4a/(p4/p5)^((y2-1)/y2);
+T5a=T4a-n_turbine*(T4a-T5);
+
+W_turbine=cpg*(T4a-T5a);
+disp(" Net power developed per kg/s mass flow =")
+disp(W_turbine)
+disp("kW")
+
+
+disp("(iii) Work ratio =")
+W_ratio=W_turbine/(W_turbine+W_compressor);
+disp(W_ratio)
+
+
+disp("(iv) Thermal efficiency of the unit")
+Qs=cpg*(T3-T2a);
+n_thermal=W_turbine/Qs*100;
+disp("n_thermal =")
+disp(n_thermal)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.46/46.sce b/551/CH13/EX13.46/46.sce new file mode 100755 index 000000000..2e064a6db --- /dev/null +++ b/551/CH13/EX13.46/46.sce @@ -0,0 +1,27 @@ +clc
+T1=288; //K
+rp=4; //rp=p2/p1=p3/p4
+n_compressor=0.82;
+e=0.78; //Effectiveness of the heat exchanger
+n_turbine=0.70;
+T3=873; //K
+y=1.4;
+R=0.287;
+
+T2=T1*(rp)^((y-1)/y);
+T2a=(T2-T1)/n_compressor + T1;
+T4=T3/rp^((y-1)/y);
+T4a=T3-n_turbine*(T3-T4);
+
+cp=R*y/(y-1);
+W_compressor=cp*(T2a-T1);
+W_turbine=cp*(T3-T4a);
+W_net=W_turbine-W_compressor;
+
+T5=e*(T4a-T2a) + T2a;
+Qs=cp*(T3-T5);
+
+n_cycle=W_net/Qs*100;
+disp("Efficiency =")
+disp(n_cycle)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.47/47.sce b/551/CH13/EX13.47/47.sce new file mode 100755 index 000000000..75b6f70a2 --- /dev/null +++ b/551/CH13/EX13.47/47.sce @@ -0,0 +1,50 @@ +clc
+
+//Simple cycle
+p2=4; //bar
+p1=1; //bar
+T1=293;
+n_compressor=0.8;
+n_turbine=0.85;
+ratio=90; //Air Fuel ratio
+C=41800; //kJ/kg
+cp=1.024;
+p4=1.01; //bar
+p3=3.9; //bar
+y=1.4;
+e=0.72; //thermal ratio
+
+T2=T1*(p2/p1)^((y-1)/y);
+T2a=(T2-T1)/n_compressor + T1;
+T3=C/cp/(ratio+1)+471;
+T4=T3*(p4/p3)^((y-1)/y);
+
+T4a=T3-n_turbine*(T3-T4);
+
+n_thermal1=((T3-T4a)-(T2a-T1))/(T3-T2a)*100;
+disp("Thermal efficiency of simple cycle=")
+disp(n_thermal1)
+disp("%")
+
+
+//Heat exchanger cycle
+
+T2a=471; // K (as for simple cycle)
+T3=919.5; // K (as for simple cycle)
+p3=4.04-0.14-0.05; //bar
+p4=1.01+0.05; //bar
+
+T4=T3*(p4/p3)^((y-1)/y);
+T4a=T3-n_turbine*(T3-T4);
+
+T5=e*(T4a-T2a) + T2a;
+
+n_thermal2=((T3-T4a) - (T2a-T1))/(T3-T5)*100;
+disp("Thermal efficiency of heat exchanger cycle =")
+disp(n_thermal2)
+disp("%")
+
+dn=n_thermal2-n_thermal1;
+disp("Increase in thermal efficiency =")
+disp(dn)
+disp("%")
\ No newline at end of file diff --git a/551/CH13/EX13.48/48.sce b/551/CH13/EX13.48/48.sce new file mode 100755 index 000000000..722ff5907 --- /dev/null +++ b/551/CH13/EX13.48/48.sce @@ -0,0 +1,50 @@ +clc +T1=293; //K +T6=898; //K +T8=T6; +n_c=0.8; //Efficiency of each compressor stage +n_t=0.85; //Efficiency of each turbine stage +n_mech=0.95; +e=0.8; +cpa=1.005; //kJ/kg K +cpg=1.15; //kJ/kg K +y1=1.4; +y2=1.333; + +disp("(i) Thermal efficiency") +T3=T1; + +// p2/p1=sqrt(9)=3 +T2=T1*(3)^((y1-1)/y1); +T2a=(T2-T1)/n_c + T1; +T4a=T2a; +W_c=cpa*(T2a-T1); //Work input per compressor stage +W_t=2*W_c/n_mech; //Work output of H.P. turbine +T7a=T6-W_t/cpg; +T7=T6-(T6-T7a)/n_t; + +// (p6/p7)=(T6/T7)^(y2/(y2-1))=4.82; +// p8/p9=9/4.82=1.86 +T9=T8/(1.86)^((y2-1)/y2); +T9a=T8-n_t*(T8-T9); + +W=cpg*(T8-T9a)*n_mech; //Net work output +T5=e*(T9a-T4a)+T4a; + +Q=cpg*(T6-T5)+cpg*(T8-T7a); //Heat supplied +n_thermal=W/Q*100; +disp("n_thermal =") +disp(n_thermal) +disp("%") + +disp("(ii) Work ratio") +Gross_work=W_t+W/n_mech; +W_ratio=W/Gross_work; +disp("Work ratio=") +disp(W_ratio) + + +disp("(iii) Mass flow rate =") +m=4500/W; +disp(m) +disp("kg/s")
\ No newline at end of file diff --git a/551/CH13/EX13.49/49.sce b/551/CH13/EX13.49/49.sce new file mode 100755 index 000000000..5acd314c1 --- /dev/null +++ b/551/CH13/EX13.49/49.sce @@ -0,0 +1,42 @@ +clc +T1=293; //K +T5=1023; //K +T7=T5; +p1=1.5; //bar +p2=6; //bar +n_c=0.82; +n_t=0.82; +e=0.70; +P=350; //kW +cp=1.005; //kJ/kg K +y=1.4; + +T3=T1; +px=sqrt(p1*p2); +T2=T1*(px/p1)^((y-1)/y); +T2a=T1+(T2-T1)/n_c; +T4a=T2a; +p5=p2; +T6=T5/(p5/px)^((y-1)/y); +T6a=T5-n_t*(T5-T6); +T8a=T6a; +Ta=T4a+e*(T8a-T4a); +W_net=2*cp*[(T5-T6a)-(T2a-T1)]; + +Q1=cp*(T5-T4a)+cp*(T7-T6a); //Without regenerator +Q2=cp*(T5-Ta)+cp*(T7-T6a); + +disp("n_thermal without regenerator =") +n1=W_net/Q1*100; +disp(n1) +disp("%") + +disp("n_thermal woth regenerator =") +n2=W_net/Q2*100; +disp(n2) +disp("%") + +disp("(iii) Mass of fluid circulated =") +m=P/W_net; +disp(m) +disp("kg/s")
\ No newline at end of file diff --git a/551/CH13/EX13.5/5.sce b/551/CH13/EX13.5/5.sce new file mode 100755 index 000000000..5f2622c9b --- /dev/null +++ b/551/CH13/EX13.5/5.sce @@ -0,0 +1,17 @@ +clc
+
+T1=1990; //K
+T2=850; //K
+Q=32.5/60; //kJ/s
+P=0.4; //kW
+
+n_carnot=(T1-T2)/T1;
+disp("most efficient engine is one that works on Carnot cycle")
+disp(n_carnot)
+
+n_th=P/Q;
+disp("n_thermal =")
+disp(n_th)
+
+disp("which is not feasible as no engine can be more efficient than that working on Carnot")
+disp("Hence claims of the inventor is not true.")
\ No newline at end of file diff --git a/551/CH13/EX13.7/7.sce b/551/CH13/EX13.7/7.sce new file mode 100755 index 000000000..9db6085ef --- /dev/null +++ b/551/CH13/EX13.7/7.sce @@ -0,0 +1,8 @@ +clc
+
+n=0.6;
+y=1.5;
+
+r=(1/(1-n))^(1/(y-1));
+disp("Compression ratio =")
+disp(r)
\ No newline at end of file diff --git a/551/CH13/EX13.8/8.sce b/551/CH13/EX13.8/8.sce new file mode 100755 index 000000000..cb0fb3984 --- /dev/null +++ b/551/CH13/EX13.8/8.sce @@ -0,0 +1,25 @@ +clc
+
+D=0.25; //m
+L=0.375; //m
+Vc=0.00263; //m^3
+p1=1; //bar
+T1=323; //K
+p3=25; //bar
+Vs=%pi/4*D^2*L;
+r=(Vs+Vc)/Vc;
+y=1.4;
+
+disp("(i) Air standard efficiency=")
+n_otto=1-1/(r^(y-1));
+disp(n_otto)
+
+
+disp("(ii) Mean effective pressure ")
+p2=p1*(r)^(y);
+r_p=p3/p2;
+
+p_m=p1*r*(r^(y-1) - 1)*(r_p - 1)/(y-1)/(r-1);
+disp("Mean effective pressure =")
+disp(p_m)
+disp("bar")
\ No newline at end of file diff --git a/551/CH13/EX13.9/9.sce b/551/CH13/EX13.9/9.sce new file mode 100755 index 000000000..39612f0f3 --- /dev/null +++ b/551/CH13/EX13.9/9.sce @@ -0,0 +1,50 @@ +clc
+cv=0.72; //kJ/kg K
+y=1.4;
+p1=1; //bar
+T1=300; //K
+Q=1500; //kJ/kg
+r=8;
+y=1.4;
+
+disp("(i) Pressures and temperatures at all points")
+T2=T1*(r)^(y-1);
+disp("T2=")
+disp(T2)
+disp("K")
+
+p2=p1*(r)^y;
+disp("p2=")
+disp(p2)
+disp("bar")
+
+T3=Q/cv + T2;
+disp("T3=")
+disp(T3)
+disp("K")
+
+p3=p2*T3/T2;
+disp("p3=")
+disp(p3)
+disp("bar")
+
+T4=T3/r^(y-1);
+disp("T4=")
+disp(T4)
+disp("K")
+
+p4=p3/r^(y);
+disp("p4=")
+disp(p4)
+disp("bar")
+
+
+disp("(ii) Specific work and thermal efficiency")
+SW=cv*[(T3-T2) - (T4-T1)];
+disp("Specific work =")
+disp(SW)
+disp("kJ/kg")
+
+n_th=1-1/r^(y-1);
+disp("Thermal efficiency =")
+disp(n_th)
\ No newline at end of file diff --git a/551/CH14/EX14.1/1.sce b/551/CH14/EX14.1/1.sce new file mode 100755 index 000000000..418a1d84f --- /dev/null +++ b/551/CH14/EX14.1/1.sce @@ -0,0 +1,27 @@ +clc
+T2=235; //K
+P=1.3; //kW
+
+disp("(i) C.O.P. of Carnot refrigerator =")
+COP=14000/P/60/60;
+disp(COP)
+
+
+disp("(ii) Higher temperature of the cycle =")
+T1=T2/COP + T2;
+t1=T1-273;
+disp(t1)
+disp("0C")
+
+
+disp("(iii) Heat delivered as heat pump")
+Qabs=14000/60; //Heat absorbed
+W=P*60;
+Q=Qabs+W;
+disp("Q=")
+disp(Q)
+disp("kJ/min")
+
+COP=Q/W;
+disp("COP of heat pump =")
+disp(COP)
\ No newline at end of file diff --git a/551/CH14/EX14.10/10.sce b/551/CH14/EX14.10/10.sce new file mode 100755 index 000000000..cd9106b66 --- /dev/null +++ b/551/CH14/EX14.10/10.sce @@ -0,0 +1,48 @@ +clc
+p1=1000; //kPa
+p2=100; //kPa
+p4=p1;
+p3=p2;
+E=2000; // Refrigerating effect produced in kJ/min
+T3=268; //K
+T1=303; //K
+y=1.4;
+
+disp("(i) Mass of air circulated per minute")
+T2=T1*(p2/p1)^((y-1)/y);
+e=cp*(T3-T2); //Refrigerating effect per kg; kJ/kg
+
+m=E/e;
+disp("m=")
+disp(m)
+disp("kg/min")
+
+
+disp("(ii) Compressor work (Wcomp.), expander work (Wexp.) and cycle work (Wcycle)")
+T4=T3*(p4/p3)^((y-1)/y);
+
+Wcomp=y/(y-1)*m*R*(T4-T3);
+disp("Compressor work =")
+disp(Wcomp)
+disp("kJ/min")
+
+Wexp=y/(y-1)*m*R*(T1-T2);
+disp("Expander work =")
+disp(Wexp)
+disp("kJ/min")
+
+W_cycle=Wcomp-Wexp;
+disp("Wcycle=")
+disp(W_cycle)
+disp("kJ/min")
+
+
+disp("(iii) C.O.P. and power required")
+COP=E/W_cycle;
+disp("COP =")
+disp(COP)
+
+P=W_cycle/60;
+disp("Power required =")
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.11/11.sce b/551/CH14/EX14.11/11.sce new file mode 100755 index 000000000..6b75dc31d --- /dev/null +++ b/551/CH14/EX14.11/11.sce @@ -0,0 +1,55 @@ +clc
+y=1.4;
+cp=1.003; //kJ/kg K
+T3=289; //K
+T1=314; //K
+p1=5.2; //bar
+p2=1; //bar
+capacity=6; //tonnes
+R=287; //J/kg K
+l=0.2; //m
+
+T4=T3*(p1/p2)^((y-1)/y);
+T2=T1*(p2/p1)^((y-1)/y);
+
+
+disp("(i) C.O.P. =")
+COP=T2/(T1-T2);
+disp(COP)
+
+disp("(ii) Mass of air in circulation")
+e=cp*(T3-T2); //Refrigerating effect per kg of air
+E=capacity*14000; //Refrigerating effect produced by the refrigerating machine in kJ/h
+
+m=E/e/60;
+disp("mass of air in circulation =")
+disp(m)
+disp("kg/min")
+
+
+disp("Piston displacement of compressor")
+V3=m*R*T3/p2/10^5;
+
+V_swept=V3/2/240;
+
+d_c=sqrt(V_swept/l/%pi*4);
+
+disp("Diameter or bore of the compressor cylinder =")
+disp(d_c*1000)
+disp("mm")
+
+disp("Piston displacement of expander")
+V2=m*R*T2/p2/10^5;
+V_swept=V2/2/240;
+
+d_c=sqrt(V_swept/l/%pi*4);
+disp("Diameter or bore of the expander cylinder =")
+disp(d_c*1000)
+disp("mm")
+
+
+disp("(v) Power required to drive the unit")
+W=capacity*14000/COP/3600;
+disp("power =")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.12/12.sce b/551/CH14/EX14.12/12.sce new file mode 100755 index 000000000..af02dde34 --- /dev/null +++ b/551/CH14/EX14.12/12.sce @@ -0,0 +1,30 @@ +clc
+m=6; //kg/min
+n_relative=0.50;
+cpw=4.187; //kJ/kg K
+L=335; //kJ/kg
+
+h_f2=31.4; //kJ/kg
+h_fg2=154; //kJ/kg
+h_f3=59.7; //kJ/kg
+h_fg3=138; //kJ/kg
+h_f4=59.7; //kJ/kg
+x2=0.6;
+s_f3=0.2232; //kJ/kg K
+s_f2=0.1251; //kJ/kg K
+T2=268; //K
+T3=298; //K
+
+h2=h_f2+x2*h_fg2;
+x3=((s_f2-s_f3)+x2*(h_fg2/T2))*T3/h_fg3;
+h3=h_f3+x3*h_fg3;
+h1=h_f4;
+COP_th=(h2-h1)/(h3-h2); //Theoritical COP
+COP=n_relative*COP_th;
+
+Q=cpw*(20-0) + L; //Heat extracted from 1 kg of water at 20°C for the formation of 1 kg of ice at 0°C
+
+m_ice=COP*m*(h3-h2)/Q*60*24/1000; //in 24 hours
+disp("m_ice=")
+disp(m_ice)
+disp("tonnes")
\ No newline at end of file diff --git a/551/CH14/EX14.13/13.sce b/551/CH14/EX14.13/13.sce new file mode 100755 index 000000000..4449b3862 --- /dev/null +++ b/551/CH14/EX14.13/13.sce @@ -0,0 +1,25 @@ +clc
+L=335; //kJ/kg
+h3=1319.22; //kJ/kg
+h1=100.04; //kJ/kg
+h4=h1;
+s_f2=-2.1338; //kJ/kg K
+s_g2=5.0585; //kJ/kg K
+s_g3=4.4852; //kJ/kg K
+h_f2=-54.56; //kJ/kg
+h_g2=1304.99; //kJ/kg
+
+x2=(s_g3-s_f2)/(s_g2-s_f2);
+
+h2=h_f2+x2*(h_g2-h_f2);
+COP_theoritical=(h2-h1)/(h3-h2);
+COP_actual=0.62*COP_theoritical;
+RE=COP_actual*(h3-h2); //Actual refrigerating effect per kg
+Q=28*1000*L/24/3600; //Heat to be extracted per second
+
+m=Q/RE; //Mass of refrigerant circulated per second
+
+W=m*(h3-h2);
+disp("Power required =")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.14/14.sce b/551/CH14/EX14.14/14.sce new file mode 100755 index 000000000..b373abaf6 --- /dev/null +++ b/551/CH14/EX14.14/14.sce @@ -0,0 +1,31 @@ +clc
+h_f2=158.2; //kJ/kg
+x2=0.62;
+h_fg2=1280.8;
+h1=298.9; //kJ/kg
+h_f4=h1;
+s_f2=0.630; //kJ/kg K
+T2=268; //K
+T3=298; //K
+s_f3=1.124; //kJ/kg K
+h_fg3=1167.1; //kJ/kg
+m=6.4; //kg/min
+cp=4.187;
+L=335; //kJ/kg
+h_f3=298.9; //kJ/kg
+
+h2=h_f2+x2*h_fg2;
+x3=((s_f2-s_f3)+x2*h_fg2/T2)/h_fg3*T3;
+h3=h_f3+x3*h_fg3;
+
+COP_theoritical=(h2-h1)/(h3-h2);
+COP_actual=0.55*COP_theoritical;
+
+W1=h3-h2; //Work done per kg of refrigerant
+W=m*W1/60; //Work done per second kJ/s
+
+Q=15*cp+L;
+m_ice=W*3600*24/Q;
+disp("Amount of ice formed in 24 hours =")
+disp(m_ice)
+disp("kg")
\ No newline at end of file diff --git a/551/CH14/EX14.15/15.sce b/551/CH14/EX14.15/15.sce new file mode 100755 index 000000000..a7fb1da78 --- /dev/null +++ b/551/CH14/EX14.15/15.sce @@ -0,0 +1,30 @@ +clc
+RE=5*14000/3600; //Total refrigeration produced in kg/s
+h2=183.19; //kJ/kg
+h3=209.41; //kJ/kg
+h4=74.59; //kJ/kg
+h1=h4;
+
+disp("(i) The refrigerant flow rate")
+RE_net=h2-h1; //Net refrigerating effect produced per kg
+m=RE/RE_net;
+disp("Refrigerant flow rate =")
+disp(m)
+disp("kg/s")
+
+
+disp("(ii) The C.O.P. =")
+COP=(h2-h1)/(h3-h2);
+disp(COP)
+
+
+disp("(iii) The power required to drive the compressor =")
+P=m*(h3-h2);
+disp(P)
+disp("kW")
+
+
+disp("(iv) The rate of heat rejection to the condenser =")
+rate=m*(h3-h4);
+disp(rate)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.16/16.sce b/551/CH14/EX14.16/16.sce new file mode 100755 index 000000000..167ff6992 --- /dev/null +++ b/551/CH14/EX14.16/16.sce @@ -0,0 +1,129 @@ +clc
+
+disp("(i) If an expansion cylinder is used in a vapour compression system, the work recovered would be extremely small, in fact not even sufficient to overcome the mechanical friction. It will not be possible to gain any work. Further, the expansion cylinder is bulky. On the other hand the expansion valve is a very simple and handy device, much cheaper than the expansion cylinder. It does not need installation, lubrication or maintenance.")
+disp("The expansion valve also controls the refrigerant flow rate according to the requirement, in addition to serving the function of reducting the pressure of the refrigerant.")
+
+
+disp("(ii) The comparison between centrifugal and reciprocating compressors ")
+
+disp("1.Suitability")
+
+disp("Centrifugal compressor")
+disp("Suitable for handling large volumes of air at low pressures")
+
+disp("Reciprocating compressor")
+disp("Suitable for low discharges of air at high pressure.")
+
+
+disp("2.Operational speeds")
+
+disp("Centrifugal compressor")
+disp("Usually high")
+
+disp("Reciprocating compressor")
+disp("Low")
+
+
+disp("3.Air supply")
+
+disp("Centrifugal compressor")
+disp("Continuous")
+
+disp("Reciprocating compressor")
+disp("Pulsating")
+
+
+disp("4.Balancing")
+
+disp("Centrifugal compressor")
+disp("Less Vibrations")
+
+disp("Reciprocating compressor")
+disp("Cyclic vibrations occur")
+
+
+disp("5.Lubrication system")
+
+disp("Centrifugal compressor")
+disp("Generally simple lubrication systems are required.")
+
+disp("Reciprocating compressor")
+disp("Generally complicated")
+
+
+disp("6.Quality of air delivered")
+
+disp("Centrifugal compressor")
+disp("Air delivered is relatively more clean")
+
+disp("Reciprocating compressor")
+disp("Generally contaminated with oil.")
+
+
+disp("7.Air compressor size")
+
+disp("Centrifugal compressor")
+disp("Small for given discharge")
+
+disp("Reciprocating compressor")
+disp("Large for same discharge")
+
+
+disp("8.Free air handled")
+
+disp("Centrifugal compressor")
+disp("2000-3000 m3/min")
+
+disp("Reciprocating compressor")
+disp("250-300 m3/min")
+
+
+disp("9.Delivery pressure")
+
+disp("Centrifugal compressor")
+disp("Normally below 10 bar")
+
+disp("Reciprocating compressor")
+disp("500 to 800 bar")
+
+
+disp("10.Usual standard of compression")
+
+disp("Centrifugal compressor")
+disp("Isentropic compression")
+
+disp("Reciprocating compressor")
+disp("Isothermal compression")
+
+
+disp("11.Action of compressor")
+
+disp("Centrifugal compressor")
+disp("Dynamic action")
+
+disp("Reciprocating compressor")
+disp("Positive displacement")
+
+
+disp("(iii)")
+h2=344.927; //kJ/kg
+h4=228.538; //kJ/kg
+h1=h4;
+cpv=0.611; ///kJ/kg0C
+// s2=s3
+t3=39.995; //0C
+h3=363.575+cpv*(t3-30);
+Rn=h2-h1;
+W=h3-h2;
+
+COP=Rn/W;
+disp("COP =")
+disp(COP)
+
+cp=2.0935; //kJ/kg 0C
+Q=2400/24/3600*[4.187*(15-0)+335+cp*(0-(-5))];
+
+W=Q/COP;
+disp("Work required =")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.17/17.sce b/551/CH14/EX14.17/17.sce new file mode 100755 index 000000000..f69510832 --- /dev/null +++ b/551/CH14/EX14.17/17.sce @@ -0,0 +1,28 @@ +clc +disp("(ii) Mass of refrigerant circulated per minute") +h2=352; //kJ/kg +h3=374; //kJ/kg +h4=221; //kJ/kg +h1=h4; +v2=0.08; //m^3/kg +rpm=500; +D=0.2; +L=0.15; +n_vol=0.85; + +RE=h2-h1; +V=%pi/4*D^2*L*rpm*2*n_vol; + +m=V/v2; +disp("Mass of refrigerant circulated per minute = ") +disp(m) +disp("kg/min") + +disp("(iii) Cooling capacity in tonnes of refrigeration =") +cc=50*(h2-h1)*60/14000; +disp(cc) +disp("TR") + +disp("(iv)COP =") +COP=(h2-h1)/(h3-h2); +disp(COP)
\ No newline at end of file diff --git a/551/CH14/EX14.18/18.sce b/551/CH14/EX14.18/18.sce new file mode 100755 index 000000000..750fab604 --- /dev/null +++ b/551/CH14/EX14.18/18.sce @@ -0,0 +1,22 @@ +clc
+te=-10; //0C
+tc=40; //0C
+h3=220; //kJ/kg
+h2=183.1; //kJ/kg
+h1=74.53; //kJ/kg
+h_f4=26.85; //kJ/kg
+m=1; //kg
+
+disp("(i) The C.O.P. the cycle =")
+COP=(h2-h1)/(h3-h2);
+disp(COP)
+
+disp("(ii) Refrigerating capacity =")
+RC=m*(h2-h1);
+disp(RC)
+disp("kJ/min")
+
+disp("Compressor power =")
+CP=m*(h3-h2)/60;
+disp(CP)
+disp("kJ/s")
\ No newline at end of file diff --git a/551/CH14/EX14.19/19.sce b/551/CH14/EX14.19/19.sce new file mode 100755 index 000000000..93899bc95 --- /dev/null +++ b/551/CH14/EX14.19/19.sce @@ -0,0 +1,33 @@ +clc
+h2=178.61; //kJ/kg
+h3a=203.05; //kJ/kg
+h_f4=74.53; //kJ/kg
+h1=h_f4;
+s3a=0.682; //kJ/kg K
+s2=0.7082; //kJ/kg K
+cp=0.747; //kJ/kg K
+T3a=313; //K
+CE=20; //Cooling effect
+C=0.03;
+v_g=0.1088;
+p_d=9.607;
+p_s=1.509;
+n=1.13;
+
+m=CE/(h2-h1);
+T3=T3a*%e^((s2-s3a)/cp)
+h3=h3a+cp*(T3-T3a);
+
+P=m*(h3-h2);
+disp("Power required by the machine =")
+disp(P)
+disp("kW")
+
+n_vol=1+C-C*(p_d/p_s)^(1/n); //Volumetric efficiency
+V1=m*v_g; //volume of refrigerant at the intake conditions
+V_swept=V1/n_vol;
+
+V=V_swept*60/300;
+disp("Piston displacement =")
+disp(V)
+disp("m^3")
\ No newline at end of file diff --git a/551/CH14/EX14.2/2.sce b/551/CH14/EX14.2/2.sce new file mode 100755 index 000000000..a6017eb99 --- /dev/null +++ b/551/CH14/EX14.2/2.sce @@ -0,0 +1,22 @@ +clc
+T1=308; //K
+T2=258; //K
+capacity=12; //tonne
+
+COP=T2/(T1-T2);
+disp("(i) Co-efficient of performance =")
+disp(COP)
+
+
+disp("(ii) Heat rejected from the system per hour")
+W=capacity*14000/5.16;
+Q=capacity*14000+W;
+disp("Q=")
+disp(Q)
+disp("kJ/h")
+
+
+disp("(iii) Power required =")
+P=W/60/60;
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.20/20.sce b/551/CH14/EX14.20/20.sce new file mode 100755 index 000000000..091451387 --- /dev/null +++ b/551/CH14/EX14.20/20.sce @@ -0,0 +1,37 @@ +clc
+h2=1450.22; //kJ/kg
+h3a=1488.57; //kJ/kg
+h_f4=366.072; //kJ/kg
+cpl2=4.556; //kJ/kg K
+cpv1=2.492; //kJ/kg K
+cpv2=2.903; //kJ/kg K
+T1=303; //K
+T2=308; //K
+s3a=5.2086; //kJ/kg K
+s2=5.755; //kJ/kg K
+T3a=308; //K
+N=1000;
+
+h_f4a=h_f4-cpl2*(T2-T1);
+h1=h_f4a;
+T3=T3a*%e^((s2-s3a)/cpv2);
+h3=h3a+cpv2*(T3-T3a);
+m=50/(h2-h1);
+
+
+disp("(i) Power required =")
+P=m*(h3-h2);
+disp(P)
+disp("kW")
+
+
+disp("(ii) Cylinder dimensions ")
+D=(m*4*60/%pi/1.2/N/0.417477)^(1/3);
+disp("Diameter of cylinder =")
+disp(D)
+disp("m")
+
+L=1.2*D;
+disp("Length of the cylinder=")
+disp(L)
+disp("m")
\ No newline at end of file diff --git a/551/CH14/EX14.21/21.sce b/551/CH14/EX14.21/21.sce new file mode 100755 index 000000000..d38900f4c --- /dev/null +++ b/551/CH14/EX14.21/21.sce @@ -0,0 +1,17 @@ +clc
+cooling_load=150; //W
+n_vol=0.8;
+N=720; //rpm
+h2=183; //kJ/kg
+h1=74.5; //kJ/kg
+v2=0.08; //m^3/kg
+
+m=cooling_load/(108.5*1000);
+disp("Mass flow rate of the refrigerant =")
+disp(m)
+disp("kJ/s")
+
+d=m*v2/n_vol;
+disp("Displacement volume of the compressor =")
+disp(d)
+disp("m^3/s")
\ No newline at end of file diff --git a/551/CH14/EX14.22/22.sce b/551/CH14/EX14.22/22.sce new file mode 100755 index 000000000..66b87d752 --- /dev/null +++ b/551/CH14/EX14.22/22.sce @@ -0,0 +1,26 @@ +clc
+h2=183.2; //kJ/kg
+h3=222.6; //kJ/kg
+h4=84.9; //kJ/kg
+
+v2=0.0767; //m^3/kg
+v3=0.0164; //m^3/kg
+v4=0.00083; //m^3/kg
+
+V=1.5*1000*10^(-6); //Piston displacement volume m^3/revolution
+n_vol=0.80;
+
+disp("(i) Power rating of the compressor (kW)")
+discharge=V*1600*n_vol; //Compressor discharge
+m=discharge/v2;
+
+P=m/60*(h3-h2); //kW
+disp("Power =")
+disp(P)
+disp("kW")
+
+
+disp("(ii) Refrigerating effect =")
+RE=m/60*(h2-h4);
+disp(RE)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.23/23.sce b/551/CH14/EX14.23/23.sce new file mode 100755 index 000000000..d139ea66c --- /dev/null +++ b/551/CH14/EX14.23/23.sce @@ -0,0 +1,21 @@ +clc
+COP=6.5;
+W=50; //kW
+h3a=201.45; //kJ/kg
+h_f4=69.55; //kJ/kg
+h1=h_f4;
+h2=187.53; //kJ/kg
+cp=0.6155; //kJ/kg
+t3a=35; //0C
+
+RC=W*COP; //Refrigerating capacity
+Q1=h2-h_f4; //Heat extracted per kg of refrigerant
+rate=RC/Q1; //Refrigerant flow rate
+Q2=W/rate; //Heat input per kg
+h=h2+Q2; //Enthalpy of vapour after compression
+Q=h-h3a; //Superheat
+
+t3=Q/cp+t3a;
+disp("t3=")
+disp(t3)
+disp("°C")
\ No newline at end of file diff --git a/551/CH14/EX14.24/24.sce b/551/CH14/EX14.24/24.sce new file mode 100755 index 000000000..e3ce463f9 --- /dev/null +++ b/551/CH14/EX14.24/24.sce @@ -0,0 +1,24 @@ +clc
+Q1=500; //total heating requirement of 500 kJ/min
+n_compressor=0.8;
+s1=0.7035; //kJ/kg K
+s2=0.6799; //kJ/kg K
+T2=322.31; //K
+cp=0.7; //kJ/kg K
+h_v2=206.24; //kJ/kg
+h_l2=84.21; //kJ/kg
+h_v1=182.07 //kJ/kg
+
+Q2=Q1/n_compressor; //Heat rejected by the cycle
+
+//Entropy of dry saturated vapour at 2 bar= Entropy of superheated vapour at 12 bar
+T=T2*%e^((s1-s2)/cp);
+
+H=h_v2+cp*(T-T2); //Enthalpy of superheated vapour at 12 bar
+Q3=H-h_l2; //Heat rejected per cycle
+m=Q2/Q3; //kg/min
+W=m*(H-h_v1)/60; //kW
+W_actual=W/n_compressor;
+disp("Power =")
+disp(W_actual)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.25/25.sce b/551/CH14/EX14.25/25.sce new file mode 100755 index 000000000..3ca6233aa --- /dev/null +++ b/551/CH14/EX14.25/25.sce @@ -0,0 +1,60 @@ +clc
+h2a=183.2; //kJ/kg K
+cpv=0.733; //Vapour specific heat in kJ/kg K
+cpl=1.235; //Liquid specific heat in kJ/kg K
+s2a=0.7020; //Entropy of vapour in kJ/kg K
+s3a=0.6854; //Entropy of vapour in kJ/kg K
+T2=270; //K
+T2a=263; //K
+T3a=303; //K
+h3a=199.6; //kJ/kg
+h_f4=64.6; //kJ/kg
+dT4=6; //dT4=T4-T4a
+v2a=0.0767;
+n=2; //number of cylinder
+
+h2=h2a+cpv*(T2-T2a);
+s2=s2a+cpv*log(T2/T2a);
+
+T3=T3a*%e^((s2-s3a)/cpv);
+h3=h3a+cpv*(T3-T3a);
+h_f4a=h_f4-cpl*dT4;
+h1=h_f4a;
+
+v2=v2a/T2a*T2;
+
+disp("(i) Refrigerating effect per kg =")
+RE=h2-h1;
+disp(RE)
+disp("kJ/kg")
+
+disp("(ii) Mass of refrigerant to be circulated per minute =")
+m=2400/RE;
+disp(m)
+disp("kg/min")
+
+disp("(iii) Theoretical piston displacement per minute =")
+v=m*v2;
+disp(v)
+disp("m^3/min")
+
+disp("(iv) Theoretical power required to run the compressor = ")
+P=m/60*(h3-h2);
+disp(P)
+disp("kW")
+
+disp("(v) Heat removed through the condenser per min =")
+Q=m*(h3-h_f4a);
+disp(Q)
+disp("kJ/min")
+
+disp("(vi) Theoretical bore (d) and stroke (l)")
+d=(v/n/%pi*4/1.25/1000)^(1/3)*1000;
+disp("Theroritical bore =")
+disp(d)
+disp("mm")
+
+disp("stroke =")
+l=1.25*d;
+disp(l)
+disp("mm")
\ No newline at end of file diff --git a/551/CH14/EX14.26/26.sce b/551/CH14/EX14.26/26.sce new file mode 100755 index 000000000..3222524de --- /dev/null +++ b/551/CH14/EX14.26/26.sce @@ -0,0 +1,26 @@ +clc
+h2=1597; //kJ/kg
+h3=1790; //kJ/kg
+h4=513; //kJ/kg
+h1=h4;
+t3=58; //0C
+x1=0.13;
+tc=27; //0C
+capacity=10.5; //tonnes
+
+disp("(i) Condition of the vapour at the outlet of the compressor =")
+t=t3-tc;
+disp(t)
+disp("°C")
+
+disp("(ii) Condition of vapour at entrance to evaporator =")
+disp(x1)
+
+disp("COP =")
+COP=(h2-h1)/(h3-h2);
+disp(COP)
+
+disp("(iv) Power required =")
+P=capacity*14000/COP/3600;
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.27/27.sce b/551/CH14/EX14.27/27.sce new file mode 100755 index 000000000..c3db653fc --- /dev/null +++ b/551/CH14/EX14.27/27.sce @@ -0,0 +1,49 @@ +clc
+h2=615; //kJ/kg
+h3=664; //kJ/kg
+h4=446; //kJ/kg
+h1=h4;
+v2=0.14; //m^3/kg
+capacity=20; //tonnes
+n=6; //number of cylinder
+
+disp("(i) Refrigerating effect per kg =")
+RE=h2-h1;
+disp(RE)
+disp("kJ/kg")
+
+disp("(ii) Mass of refrigerant to be circulated per minute =")
+m=capacity*14000/RE/60;
+disp(m)
+disp("kg/min")
+
+disp("(iii) Theoretical piston displacement =")
+v=v2*m;
+disp(v)
+disp("m^3/min")
+
+disp("(iv) Theoretical power =")
+P=m/60*(h3-h2);
+disp(P)
+disp("kW")
+
+disp("(v)COP =")
+COP=(h2-h1)/(h3-h2);
+disp(COP)
+
+disp("(vi) Heat removed through the condenser =")
+Q=m*(h3-h4);
+disp(Q)
+disp("kJ/min")
+
+disp("(vii) Theoretical displacement per minute per cylinder")
+
+d=(v/n*4/%pi/950)^(1/3)*1000;
+disp("Diameter of cylinder =")
+disp(d)
+disp("mm")
+
+l=d;
+disp("Stroke length =")
+disp(l)
+disp("mm")
\ No newline at end of file diff --git a/551/CH14/EX14.3/3.sce b/551/CH14/EX14.3/3.sce new file mode 100755 index 000000000..243ef1939 --- /dev/null +++ b/551/CH14/EX14.3/3.sce @@ -0,0 +1,11 @@ +clc
+T2=268; //K
+T1=308; //K
+Q=29; //Heat leakage from the surroundings into the cold storage in kW
+COP_ideal=T2/(T1-T2);
+COP_actual=1/3*COP_ideal;
+
+W=Q/COP_actual;
+disp("Power required =")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.4/4.sce b/551/CH14/EX14.4/4.sce new file mode 100755 index 000000000..ae0563c4d --- /dev/null +++ b/551/CH14/EX14.4/4.sce @@ -0,0 +1,13 @@ +clc
+T1=293; //K
+T2=265; //K
+T0=273; //K
+L=335; //Latent heat of ice in kJ/kg
+cpw=4.18;
+
+COP=T2/(T1-T2);
+Rn=cpw*(T1-T0)+L;
+m_ice=COP*3600/Rn;
+disp("ice formed per kWh =")
+disp(m_ice)
+disp("kg")
\ No newline at end of file diff --git a/551/CH14/EX14.5/5.sce b/551/CH14/EX14.5/5.sce new file mode 100755 index 000000000..3d88afec2 --- /dev/null +++ b/551/CH14/EX14.5/5.sce @@ -0,0 +1,16 @@ +clc
+T1=291; //K
+T2=265; //K
+T0=273; //K
+cpw=4.18; //kJ/kg
+cpi=2.09; //kJ/kg
+L=334; //kJ/kg
+m=400; //kg
+
+COP=T2/(T1-T2);
+Rn=cpw*(T1-T0) + L + cpi*(T0-T2);
+
+W=Rn*m/COP/3600; //kJ/s
+disp("Least power =")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.6/6.sce b/551/CH14/EX14.6/6.sce new file mode 100755 index 000000000..d327a80a7 --- /dev/null +++ b/551/CH14/EX14.6/6.sce @@ -0,0 +1,26 @@ +clc
+cpw=4.18; //kJ/kg
+
+disp("(i) Quantity of ice produced")
+t=20; //0C
+L=335; //kJ/kg
+capacity=280; //tonnes
+
+Q1=cpw*t + L; //Heat to be extracted per kg of water (to form ice at 0°C)
+Rn=capacity*14000; //kJ/h
+
+m_ice=Rn*24/Q1/1000;
+disp("Quantity of ice produced in 24 hours =")
+disp(m_ice)
+disp("tonnes")
+
+
+disp("(ii) Minimum power required =")
+T1=298; //K
+T2=263; //K
+
+COP=T2/(T1-T2);
+W=Rn/COP/3600; //kJ/s
+disp("Power required =")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH14/EX14.7/7.sce b/551/CH14/EX14.7/7.sce new file mode 100755 index 000000000..cb7ab1852 --- /dev/null +++ b/551/CH14/EX14.7/7.sce @@ -0,0 +1,33 @@ +clc
+cp1=1.25; //kJ/kg 0C
+cp2=2.93; //kJ/kg 0C
+L=232; //kJ/kg
+T1=-3; //0C
+T2=-8; //0C
+T3=25; //0C
+
+Q1=cp2*(T3-T1) + L + cp1*(T1-T2); //Heat removed in 8 hours from each kg of fish
+
+Q=Q1*20*1000/8; //Heat removed by the plant /min
+
+disp("(i) Capacity of the refrigerating plant =")
+capacity=Q/14000; //tonnes
+disp(capacity)
+disp("tonnes")
+
+disp("(ii) Carnot cycle C.O.P. between this temperature range.")
+T1=298; //K
+T2=265; //K
+
+COP=T2/(T1-T2);
+disp("COP of reversed carnot cycle =")
+disp(COP)
+
+
+disp("(iii) Power required")
+COP_actual=1/3*COP;
+
+W=Q/COP_actual/3600; //kJ/s
+disp("Power =")
+disp(W)
+disp("kW")
diff --git a/551/CH14/EX14.8/8.sce b/551/CH14/EX14.8/8.sce new file mode 100755 index 000000000..df63ab405 --- /dev/null +++ b/551/CH14/EX14.8/8.sce @@ -0,0 +1,14 @@ +clc
+T1=1273; //K
+T2=298; //K
+T3=268; //K
+T4=298; //K
+
+//Let Q2/Q1=r1, r2=Q3/Q4;
+r1=298/1273; //Q2/Q1
+r2=268/298; //Q3/Q4
+
+//Let Q4/Q1=r
+r=(1-r1)/(1-r2);
+disp("The ratio in which the heat pump and heat engine share the heating load =")
+disp(r)
diff --git a/551/CH14/EX14.9/9.sce b/551/CH14/EX14.9/9.sce new file mode 100755 index 000000000..e76b69765 --- /dev/null +++ b/551/CH14/EX14.9/9.sce @@ -0,0 +1,21 @@ +clc
+y=1.4;
+n=1.35;
+cp=1.003; //kJ/kg K
+p2=1; //bar
+p1=8; //bar
+T3=282; //K
+T4=302; //K
+T1=T4;
+T4=T3*(p1/p2)^((n-1)/n);
+T2=T1*(p2/p1)^((n-1)/n);
+
+Q1=cp*(T3-T2); //Heat extracted from cold chamber per kg of air
+Q2=cp*(T4-T1); //Heat rejected in the cooling chamber per kg of air
+cv=cp/y;
+R=cp-cv;
+W=n/(n-1)*R*((T4-T3) - (T1-T2));
+
+COP=Q1/W;
+disp("COP=")
+disp(COP)
\ No newline at end of file diff --git a/551/CH15/EX15.1/1.sce b/551/CH15/EX15.1/1.sce new file mode 100755 index 000000000..2a4d6648f --- /dev/null +++ b/551/CH15/EX15.1/1.sce @@ -0,0 +1,10 @@ +clc
+t1=60; //0C
+t2=35; //0C
+L=0.22; //m
+k=0.51; //W/m 0C
+
+q=k*(t1-t2)/L;
+disp("Rate of heat transfer per m^2 =")
+disp(q)
+disp("W/m^2")
\ No newline at end of file diff --git a/551/CH15/EX15.10/10.sce b/551/CH15/EX15.10/10.sce new file mode 100755 index 000000000..6390ae5fe --- /dev/null +++ b/551/CH15/EX15.10/10.sce @@ -0,0 +1,16 @@ +clc
+r1=0.06; //m
+r2=0.12; //m
+r3=0.16; //m
+k_A=0.24; //W/m 0C
+k_B=0.4; //W/m 0C
+h_hf=60; //W/m^2 0C
+h_cf=12; //W/m^2 0C
+t_hf=65; //0C
+t_cf=20; //0C
+L=60; //m
+
+Q=2*%pi*L*(t_hf-t_cf)/(1/h_hf/r1 + log(r2/r1)/k_A + log(r3/r2)/k_B + 1/h_cf/r3);
+disp("Rate of heat loss =")
+disp(Q)
+disp("W")
\ No newline at end of file diff --git a/551/CH15/EX15.11/11.sce b/551/CH15/EX15.11/11.sce new file mode 100755 index 000000000..f80dd41a5 --- /dev/null +++ b/551/CH15/EX15.11/11.sce @@ -0,0 +1,20 @@ +clc
+r1=0.06; //m
+r2=0.08; //m
+k_A=42; //W/m 0C
+k_B=0.8; //W/m 0C
+t_hf=150; //0C
+t_cf=20; //0C
+h_hf=100; //W/m^2 0C
+h_cf=30; //W/m^2 0C
+
+//Q=2.1*2*%pi*r*L kW
+//Q=0.989*L*10^3 W
+
+//Q=2*%pi*L*(t_hf-t_cf)/(1/h_hf/r1 + log(r2/r1)/k_A + log(r3/r2)/k_B + 1/h_cf/r3)
+//By solving above equation, using hit and trial method we get
+r3=0.105; //m
+thickness=(r3-r2)*1000; //mm
+disp("Thickness of insulation =")
+disp(thickness)
+disp("mm")
\ No newline at end of file diff --git a/551/CH15/EX15.12/12.sce b/551/CH15/EX15.12/12.sce new file mode 100755 index 000000000..969132388 --- /dev/null +++ b/551/CH15/EX15.12/12.sce @@ -0,0 +1,10 @@ +clc
+r2=0.7; //m
+r1=0.61; //m
+dt=220; //dt=t1-t2; 0C
+k=0.083; //W/m 0C
+
+Q=dt/((r2-r1)/(4*%pi*k*r1*r2));
+disp("Rate of heat leakage =")
+disp(Q)
+disp("W")
\ No newline at end of file diff --git a/551/CH15/EX15.13/13.sce b/551/CH15/EX15.13/13.sce new file mode 100755 index 000000000..223f3a617 --- /dev/null +++ b/551/CH15/EX15.13/13.sce @@ -0,0 +1,27 @@ +clc
+r1=0.001; //m
+r2=0.0018; //m
+k=0.12; //W/m 0C
+h0=35; //W/m^2 0C
+
+rc=k/h0;
+
+thickness=(rc-r1)*10^3; //mm
+disp("Critical thickness of insulation =")
+disp(thickness)
+disp("mm")
+
+//Percentage change in heat transfer rate :
+//Case I : The heat flow through an insulated wire
+
+//Q1=2*%pi*L*(t1-tair)/(log(r2/r1)/k + 1/h0/r2)
+
+//Case II : The heat flow through an insulated wire when critical thickness is used is given
+
+//Q2=2*%pi*L*(t1-tair)/(log(rc/r1)/k + 1/h0/rc)
+
+//%increase=(Q2-Q1)/Q1*100
+%increase=(1/(log(rc/r1)/k + 1/h0/rc)-1/(log(r2/r1)/k + 1/h0/r2))/(1/(log(r2/r1)/k + 1/h0/r2))*100;
+disp("Percentage change in heat transfer rate =")
+disp(%increase)
+disp("%")
\ No newline at end of file diff --git a/551/CH15/EX15.14/14.sce b/551/CH15/EX15.14/14.sce new file mode 100755 index 000000000..552989bdd --- /dev/null +++ b/551/CH15/EX15.14/14.sce @@ -0,0 +1,9 @@ +clc
+A=1*1.5; //m^2
+ts=300; //0C
+tf=20; //0C
+h=20; //W/m^2 0C
+Q=h*A*(ts-tf)/10^3; //kW
+disp("Rate of heat transfer =")
+disp(Q)
+disp("kW")
\ No newline at end of file diff --git a/551/CH15/EX15.15/15.sce b/551/CH15/EX15.15/15.sce new file mode 100755 index 000000000..308f5d0da --- /dev/null +++ b/551/CH15/EX15.15/15.sce @@ -0,0 +1,12 @@ +clc
+d=0.0015; //m
+l=0.15; //m
+A=%pi*d*l;
+ts=120; //0C
+tf=100; //0C
+h=4500; //W/m^2 0C
+
+Q=h*A*(ts-tf);
+disp("Electric power to be supplied =")
+disp(Q)
+disp("W")
\ No newline at end of file diff --git a/551/CH15/EX15.16/16.sce b/551/CH15/EX15.16/16.sce new file mode 100755 index 000000000..5795bdfd5 --- /dev/null +++ b/551/CH15/EX15.16/16.sce @@ -0,0 +1,22 @@ +clc
+D=0.045; //m
+l=3.2; //m
+u=0.78; //m/s
+k=0.66; //W/m K
+v=0.478*10^(-6); //m^2/s
+Pr=2.98;
+tw=70; //0C
+tf=50; //0C
+
+A=%pi*D*l;
+Re=D*u/v;
+
+h=0.023*(Re)^0.8*(Pr)^0.4/D*k;
+disp("Heat transfer co-efficient =")
+disp(h)
+disp("W/m^2 K")
+
+Q=h*A*(tw-tf)/10^3;
+disp("Rate of heat transfer =")
+disp(Q)
+disp("kW")
\ No newline at end of file diff --git a/551/CH15/EX15.17/17.sce b/551/CH15/EX15.17/17.sce new file mode 100755 index 000000000..810f96f44 --- /dev/null +++ b/551/CH15/EX15.17/17.sce @@ -0,0 +1,25 @@ +clc
+rho=983.2; //kg/m^2
+cp=4.187; //kJ/kg K
+k=0.659; //W/m 0C
+v=0.478*10^(-6); //m^2/s
+m=0.5/60; //kg/s
+D=0.02; //m
+ti=20; //0C
+t0=50; //0C
+ts=85; //surface temperature in 0C
+
+tf=1/2*(ts+(ti+t0)/2);
+A=%pi/4*D^2;
+u=m/rho/A;
+Re=D*u/v;
+//Since Re < 2000, hence the flow is laminar.
+
+Nu=3.65;
+h=Nu*k/D;
+tb=(t0+ti)/2;
+
+L=m*cp*10^3*(t0-ti)/(ts-tb)/h/D/%pi;
+disp("Length of the tube required for fully developed flow =")
+disp(L)
+disp("m")
\ No newline at end of file diff --git a/551/CH15/EX15.18/18.sce b/551/CH15/EX15.18/18.sce new file mode 100755 index 000000000..8b9d02686 --- /dev/null +++ b/551/CH15/EX15.18/18.sce @@ -0,0 +1,21 @@ +clc
+m_h=0.2; //kg/s
+m_c=0.5; //kg/s
+t_h1=75; //0C
+t_h2=45; //0C
+t_c1=20; //0C
+hi=650; //W/m^2 0C
+h0=hi;
+cph=4.187;
+cpc=cph;
+
+Q=m_h*cph*(t_h1-t_h2);
+t_c2=m_h*cph/cpc*(t_h1-t_h2)/m_c+t_c1;
+
+theta=((t_h1-t_c1)- (t_h2-t_c2))/log((t_h1-t_c1)/(t_h2-t_c2)); //Logarithmic mean temperature difference
+
+U=hi*h0/(hi+h0);
+A=Q*10^3/U/theta;
+disp("The area of heat exchanger =")
+disp(A)
+disp("m^2")
\ No newline at end of file diff --git a/551/CH15/EX15.19/19.sce b/551/CH15/EX15.19/19.sce new file mode 100755 index 000000000..4f63b58fe --- /dev/null +++ b/551/CH15/EX15.19/19.sce @@ -0,0 +1,28 @@ +clc
+t_c1=25; //0C
+t_c2=65; //0C
+cph=1.45; //kJ/kg K
+m_h=0.9; //kg/s
+t_h1=230; //0C
+t_h2=160; //0C
+U=420; //W/m^2 0C
+cpc=4.187; //kJ/kg K
+
+disp("(i) The rate of heat transfer =")
+Q=m_h*cph*(t_h1-t_h2);
+disp(Q)
+disp("kJ/s")
+
+
+disp("(ii) The mass flow rate of water =")
+m_c=Q/cpc/(t_c2-t_c1);
+disp(m_c)
+disp("kg/s")
+
+
+disp("(iii) The surface area of heat exchanger =")
+LMTD=((t_h1-t_c2)- (t_h2-t_c1))/log((t_h1-t_c2)/(t_h2-t_c1)); //logarithmic mean temperature difference
+A=Q*10^3/U/LMTD;
+disp("A=")
+disp(A)
+disp("m^2")
\ No newline at end of file diff --git a/551/CH15/EX15.2/2.sce b/551/CH15/EX15.2/2.sce new file mode 100755 index 000000000..13c3a1d78 --- /dev/null +++ b/551/CH15/EX15.2/2.sce @@ -0,0 +1,29 @@ +clc
+t1=1325; //0C
+t2=1200; //0C
+t3=25; //0C
+L=0.32; //m
+k_A=0.84; //W/m 0C
+k_B=0.16; //W/m 0C
+
+//L_B=0.32-L_A
+//(t1-t2)/(L_A/k_A)=(t1-t3)/((L_A/k_A + L_B/k_B)
+
+L_A=(t1-t2)*k_A/k_B*L/((t1-t3)-(t1-t2)*k_A/k_A+(t1-t2)*k_A/k_B); //m
+disp("L_A=")
+disp(L_A*1000)
+disp("mm")
+
+L_B=0.32-L_A; //m
+disp("L_B")
+disp(L_B*1000)
+disp("mm")
+
+
+disp("(ii) Heat loss per unit area =")
+q=(t1-t2)/L_A*k_A;
+disp(q)
+disp("W/m^2")
+
+
+disp("If another layer of insulating material is added, the heat loss from the wall will reduce ;consequently the temperature drop across the fire brick lining will drop and the interface temperature t2 will rise. As the interface temperature is already fixed. Therefore, a satisfactory solutionwill not be available by adding layer of insulation.")
\ No newline at end of file diff --git a/551/CH15/EX15.20/20.sce b/551/CH15/EX15.20/20.sce new file mode 100755 index 000000000..8053862d7 --- /dev/null +++ b/551/CH15/EX15.20/20.sce @@ -0,0 +1,25 @@ +clc
+m_s=800/60; //kg/s
+m_c=m_s;
+m_g=1350/60; //kg/s
+m_h=m_g;
+t_h1=650; //0C
+t_c1=180; //0C
+t_c2=350; //0C
+d=0.03; //m
+L=3; //m
+cph=1; //kJ/kg K
+cpc=2.71; //kJ/kg K
+h_g=250;
+h_s=600;
+
+t_h2=t_h1-(m_c*cpc*(t_c2-t_c1)/cph/m_h);
+U=h_g*h_s/(h_g+h_s);
+Q=m_h*cph*10^3*(t_h1-t_h2);
+theta=((t_h1-t_c2)- (t_h2-t_c1))/log((t_h1-t_c2)/(t_h2-t_c1)); //logarithmic mean temperature difference
+//A=N*%pi*d*L
+
+N=Q/U/theta/(%pi*d*L);
+disp("number of tubes required =")
+disp(N)
+disp("tubes")
\ No newline at end of file diff --git a/551/CH15/EX15.21/21.sce b/551/CH15/EX15.21/21.sce new file mode 100755 index 000000000..4522b7b3d --- /dev/null +++ b/551/CH15/EX15.21/21.sce @@ -0,0 +1,43 @@ +clc
+di=0.0296; //m
+d0=0.0384; //m
+U=4000; //W/m^2 0C
+V=3; //m/s
+t_c1=24; //0C
+x=0.9;
+ps=(760-660)/760*1.0133; //bar
+t_h1=51; //0C
+t_h2=51; //0C
+h_fg=2592; //kJ/kg
+t_c2=47; //0C
+P=15; //MW
+ssc=5; //specific steam consumption in kg/kWh
+cpc=4.187; //kJ?kg K
+rho=1000;
+
+m_s=P*10^3*ssc/60; //kg/min
+
+disp("(i) Mass of cooling water circulated per minute =")
+m_w=m_s*x*h_fg/cpc/(t_c2-t_c1);
+disp(m_w)
+disp("kg/min")
+
+
+disp("(ii) Condenser surface area")
+Q=m_s*x*h_fg*10^3/60;
+
+theta=((t_h1-t_c1)- (t_h2-t_c2))/log((t_h1-t_c1)/(t_h2-t_c2)); //Logarithmic mean temperature difference
+A=Q/U/theta;
+disp(A)
+disp("m^2")
+
+
+disp("(iii) Number of tubes required per pass =")
+Np=m_w/60*4/%pi/di^2/V/rho;
+disp(Np)
+
+
+disp("(iv) Tube length =")
+L=A/%pi/d0/(2*Np);
+disp(L)
+disp("m")
\ No newline at end of file diff --git a/551/CH15/EX15.22/22.sce b/551/CH15/EX15.22/22.sce new file mode 100755 index 000000000..55172284e --- /dev/null +++ b/551/CH15/EX15.22/22.sce @@ -0,0 +1,30 @@ +clc
+cp=4.187; //kJ/kg °C
+u=0.596*10^(-3); //Ns/m^2
+k=0.635; //W/m °C
+Pr=3.93;
+d=0.020; //m
+l=2; //m
+m_c=10; //kg/s
+t_c1=17; ///°C
+t_h1=100; //°C
+t_h2=100; //°C
+rho=1000;
+N=200;
+Np=N/l;
+h0=10*10^3;
+
+V=m_c*4/%pi/d^2/rho/Np;
+Re=rho*V*d/u;
+hi=k/d*0.023*(Re)^0.8*(Pr)^0.33;
+U=hi*h0/(hi+h0);
+
+//theta1=t_h1-t_c1;
+// theta2=t_h2-t_c2;
+//AMTD=(theta1+theta2)/2
+//AMTD=91.5 - 0.5*t_c2
+
+t_c2=(U*%pi*d*l*N*91.5 + m_c*cp*10^3*t_c1)/(m_c*cp*10^3 + U*%pi*d*l*N*0.5);
+disp("water exit temperature =")
+disp(t_c2)
+disp("°C")
\ No newline at end of file diff --git a/551/CH15/EX15.23/23.sce b/551/CH15/EX15.23/23.sce new file mode 100755 index 000000000..370715ca3 --- /dev/null +++ b/551/CH15/EX15.23/23.sce @@ -0,0 +1,21 @@ +clc
+A=0.12; //m^2
+T=800; //K
+a=5.67*10^(-8);
+
+disp("(i) The total rate of energy emission =")
+Eb=a*A*T^4;
+disp(Eb)
+disp("W")
+
+
+disp("(ii) The intensity of normal radiation =")
+Ibn=a*T^4/%pi;
+disp(Ibn)
+disp("W/m^2.sr")
+
+
+disp("(iii) The wavelength of maximum monochromatic emissive power =")
+wavelength=2898/T;
+disp(wavelength)
+disp("μm")
\ No newline at end of file diff --git a/551/CH15/EX15.24/24.sce b/551/CH15/EX15.24/24.sce new file mode 100755 index 000000000..b99fb8f1b --- /dev/null +++ b/551/CH15/EX15.24/24.sce @@ -0,0 +1,14 @@ +clc
+wavelength=0.49; //μm
+a=5.67*10^(-8);
+
+disp("(i) The surface temperature of the sun")
+T=2898/wavelength;
+disp(T)
+disp("K")
+
+
+disp("(ii) The heat flux at the surface of the sun =")
+E_sun=a*T^4;
+disp(E_sun)
+disp("W/m^2")
\ No newline at end of file diff --git a/551/CH15/EX15.25/25.sce b/551/CH15/EX15.25/25.sce new file mode 100755 index 000000000..30b80f44b --- /dev/null +++ b/551/CH15/EX15.25/25.sce @@ -0,0 +1,37 @@ +clc
+T=2773; //K
+lambda=1.2*10^(-6); //m
+e=0.9;
+a=5.67*10^(-8);
+
+disp("(i) Monochromatic emissive power at 1.2 μm length")
+C1=0.3742*10^(-15); //W.m^4/m^2
+C2=1.4388*10^(-4); //mK
+E_lambda_b=C1*lambda^(-5)/(exp(C2/lambda/T)-1);
+disp("E_lambda_b =")
+disp(E_lambda_b)
+disp("W/m^2")
+
+
+disp("(ii) Wavelength at which the emission is maximum =")
+lambda_max=2898/T;
+disp(lambda_max)
+disp("μm")
+
+
+disp("(iii) Maximum emissive power =")
+E_lambda_b_max=1.285*10^(-5)*T^5;
+disp(E_lambda_b_max)
+disp("W/m^2 per metre length")
+
+
+disp("(iv) Total emissive power =")
+Eb=a*T^4;
+disp(Eb)
+disp("W/m^2")
+
+
+disp("(v) Total emissive power =")
+E=e*a*T^4;
+disp(E)
+disp("W/m^2")
diff --git a/551/CH15/EX15.26/26.sce b/551/CH15/EX15.26/26.sce new file mode 100755 index 000000000..4f263654b --- /dev/null +++ b/551/CH15/EX15.26/26.sce @@ -0,0 +1,21 @@ +clc
+T1=1273; //K
+T2=773; //K
+e1=0.42;
+e2=0.72;
+a=5.67*10^(-8);
+
+disp("(i) When the body is grey with ε1 = 0.42")
+q=e1*a*(T1^4-T2^4)/10^3; //kW
+disp("Heat loss per m2 by radiation =")
+disp(q)
+disp("kW")
+
+disp("(ii) When the body is not grey")
+E_emitted=e1*a*T1^4;
+E_absorbed=e2*a*(T2)^4;
+
+q=(E_emitted-E_absorbed)/10^3;
+disp("Heat loss per m2 by radiation =")
+disp(q)
+disp("kW")
\ No newline at end of file diff --git a/551/CH15/EX15.27/27.sce b/551/CH15/EX15.27/27.sce new file mode 100755 index 000000000..d6ba5cd23 --- /dev/null +++ b/551/CH15/EX15.27/27.sce @@ -0,0 +1,27 @@ +clc
+d=0.022; //m
+di=0.18; //m
+e1=0.62;
+e2=0.82;
+rho=7845; //kg/m^3
+T1a=693; //K; For caseI
+T1b=813; //K; For caseII
+T2=1373; //K
+l=1; //m
+a=5.67*10^(-8);
+cp=0.67; //kJ/kg K
+
+A1=%pi*d*l;
+A2=%pi*di*l;
+
+
+Qi=A1*a*(T1a^4-T2^4)/(1/e1+A1/A2*(1/e2 - 1));
+
+Qe=A1*a*(T1b^4-T2^4)/(1/e1+A1/A2*(1/e2 - 1));
+
+Qav=-(Qi+Qe)/2;
+
+t_h=%pi/4*d^2*rho*cp*(T1b-T1a)*10^3/Qav;
+disp("Time required for the heating operation")
+disp(t_h)
+disp("s")
\ No newline at end of file diff --git a/551/CH15/EX15.28/28.sce b/551/CH15/EX15.28/28.sce new file mode 100755 index 000000000..7ff8ea12a --- /dev/null +++ b/551/CH15/EX15.28/28.sce @@ -0,0 +1,15 @@ +clc
+r1=0.05; //m
+r2=0.1; //m
+T1=400; //K
+T2=300; //K
+e1=0.5;
+e2=0.5;
+F_12=1;
+a=5.67*10^(-8);
+//A1/A2=r1/r2
+
+Q=a*(T1^4-T2^4)/((1-e1)/e1+1/F_12+(1-e2)/e2*r1/r2);
+disp("heat transfer rate per m2 area by radiation")
+disp(Q)
+disp("W/m^2")
\ No newline at end of file diff --git a/551/CH15/EX15.29/29.sce b/551/CH15/EX15.29/29.sce new file mode 100755 index 000000000..65c137e76 --- /dev/null +++ b/551/CH15/EX15.29/29.sce @@ -0,0 +1,26 @@ +clc
+r1=0.05; //m
+r2=0.1; //m
+r3=0.15; //m
+T1=1000; //K
+T3=500; //K
+e1=0.05;
+e2=e1;
+e3=e1;
+a=5.67*10^(-8);
+
+F_12=1;
+F_23=1;
+
+// A1*a*(T1^4-T2^4)/(((1-e1)/e1) + 1/F_12 + ((1-e2)/e2)*A1/A2) = A2*a*(T2^4-T3^4)/(((1-e2)/e2) + 1/F_23 + ((1-e3)/e3)*A2/A3)
+
+// A1/A2=r1/r2=5/10=0.5
+// A2/A3=r2/r3=10/15=0.67
+
+//Solving this we get
+T2=770; //K
+
+Q1=a*(T1^4-T2^4)/(((1-e1)/e1) + 1/F_12 + ((1-e2)/e2)*r1/r2);
+disp("Heat flow per m2 area of cylinder 1 =")
+disp(Q1)
+disp("W")
\ No newline at end of file diff --git a/551/CH15/EX15.3/3.sce b/551/CH15/EX15.3/3.sce new file mode 100755 index 000000000..89658ffeb --- /dev/null +++ b/551/CH15/EX15.3/3.sce @@ -0,0 +1,12 @@ +clc
+L_A=0.1; //m
+L_B=0.04; //m
+k_A=0.7; //W/m 0C
+k_B=0.48; //W/m 0C
+k_C=0.065; //W/m 0C
+
+//Q2=0.2*Q1
+L_C=0.8*[(L_A/k_A) + (L_B/k_B)]*k_C/0.2;
+disp("thickness of rock wool insulation =")
+disp(L_C*1000)
+disp("mm")
\ No newline at end of file diff --git a/551/CH15/EX15.30/30.sce b/551/CH15/EX15.30/30.sce new file mode 100755 index 000000000..8724f43f7 --- /dev/null +++ b/551/CH15/EX15.30/30.sce @@ -0,0 +1,17 @@ +clc
+r1=0.105; //m
+r2=0.15; //m
+T1=120; //K
+T2=300; //K
+e1=0.03;
+e2=0.03;
+h_fg=209.35; //kJ/kg
+a=5.67*10^(-8);
+F_12=1;
+
+Q=4*%pi*r1^2*a*(T1^4-T2^4)/( ((1-e1)/e1) + 1/F_12 + ((1-e2)/e2)*r1^2/r2^2);
+
+rate=-Q*3600/h_fg/1000;
+disp("Rate of evaporation = ")
+disp(rate)
+disp("kg/h")
\ No newline at end of file diff --git a/551/CH15/EX15.31/31.sce b/551/CH15/EX15.31/31.sce new file mode 100755 index 000000000..fad4432ea --- /dev/null +++ b/551/CH15/EX15.31/31.sce @@ -0,0 +1,14 @@ +clc
+T1=91; //K
+T2=303; //K
+e1=0.03;
+e2=0.03;
+d1=0.3; //m
+d2=0.45; //m
+a=5.67*10^(-8);
+F_12=1;
+
+Q=4*%pi*(d1/2)^2*a*(T1^4-T2^4)/( ((1-e1)/e1) + 1/F_12 + ((1-e2)/e2)*d1^2/d2^2);
+disp("Rate of heat flow =")
+disp(Q)
+disp("W")
\ No newline at end of file diff --git a/551/CH15/EX15.32/32.sce b/551/CH15/EX15.32/32.sce new file mode 100755 index 000000000..dbb3932db --- /dev/null +++ b/551/CH15/EX15.32/32.sce @@ -0,0 +1,22 @@ +clc +e1=0.3; +e2=0.8; +e3=0.04; +A1=1; //m^2 +A2=A1; +A3=A1; + +// (E_b1 - E_b3)/[(1-e1)/e1+1+(1-e3)/e3]=(E_b3 - E_b2)/[(1-e3)/e3+1+(1-e2)/e2] + +// a*(T1^4-T3^4)/(1/e1+1/e3-1)=a*(T3^4-T2^4)/(1/e3+1/e2-1) + +// T3^4=0.48*(T1^4+1.08*T2^4) + +// Q12=a*(T1^4-T2^4)/(1/e1+1/e2-1) +// Q13=a*(T1^4-T3^4)/(1/e1+1/e3-1) + +// %reduction=(Q_12-Q13)/Q12; +%reduction=1-0.131*0.52; +disp("Percentage reduction in heat flow due to shield =") +disp(%reduction) +disp("%")
\ No newline at end of file diff --git a/551/CH15/EX15.4/4.sce b/551/CH15/EX15.4/4.sce new file mode 100755 index 000000000..b76619f5e --- /dev/null +++ b/551/CH15/EX15.4/4.sce @@ -0,0 +1,24 @@ +clc
+L_A=0.2; //m
+L_C=0.006; //m
+L_D=0.1; //m
+t1=1150; //0C
+t2=40; //0C
+dt=t1-t2;
+k_A=1.52; //W/m 0C
+k_B=0.138; //W/m 0C
+k_D=0.138; //W/m 0C
+k_C=45; //W/m 0C
+q=400; //W/m^2
+
+disp("(i) The value of x = (L_C) ")
+L_B=((t1-t2)/q - (L_A/k_A+L_C/k_C+L_D/k_D))*k_B*1000;
+disp("L_B =")
+disp(L_B)
+disp("mm")
+
+
+disp("(ii) Temperature of the outer surface of the steel plate t_so =")
+t_so=q*L_D/k_D + t2;
+disp(t_so)
+disp("0C")
\ No newline at end of file diff --git a/551/CH15/EX15.5/5.sce b/551/CH15/EX15.5/5.sce new file mode 100755 index 000000000..2e00157c1 --- /dev/null +++ b/551/CH15/EX15.5/5.sce @@ -0,0 +1,31 @@ +clc
+k_A=150; //W/m 0C
+k_B=30; //W/m 0C
+k_C=65; //W/m 0C
+k_D=50; //W/m 0C
+
+L_A=0.03; //m
+L_B=0.08; //m
+L_C=L_B;
+L_D=0.05; //m
+
+A_A=0.01; //m^2
+A_B=0.003; //m^2
+A_C=0.007; //m^2
+A_D=0.01; //m^2
+
+t1=400; //0C
+t4=60; //0C
+
+R_thA=L_A/k_A/A_A;
+R_thB=L_B/k_B/A_B;
+R_thC=L_C/k_C/A_C;
+R_thD=L_D/k_D/A_D;
+
+R_th_eq=R_thB*R_thC/(R_thB+R_thC);
+R_th_total=R_thA+R_th_eq+R_thD;
+
+Q=(t1-t4)/R_th_total;
+disp("Q=")
+disp(Q)
+disp("W")
\ No newline at end of file diff --git a/551/CH15/EX15.6/6.sce b/551/CH15/EX15.6/6.sce new file mode 100755 index 000000000..a252cef4d --- /dev/null +++ b/551/CH15/EX15.6/6.sce @@ -0,0 +1,21 @@ +clc
+L=0.012; //m
+t_hf=95; //0C
+t_cf=15; //0C
+k=50; //W/m 0C
+h_hf=2850; //W/m^2 0C
+h_cf=10; //W/m^2 0C
+
+disp("(i) Rate of heat loss per m^2 of the tank surface area")
+U=1/(1/h_hf + L/k + 1/h_cf);
+A=1; //m^2
+q=U*A*(t_hf-t_cf);
+disp("q=")
+disp(q)
+disp("W/m^2")
+
+
+disp("(ii) Temperature of the outside surface of the tank =")
+t2=q/h_cf+t_cf;
+disp(t2)
+disp("0C")
\ No newline at end of file diff --git a/551/CH15/EX15.7/7.sce b/551/CH15/EX15.7/7.sce new file mode 100755 index 000000000..7c396f9f6 --- /dev/null +++ b/551/CH15/EX15.7/7.sce @@ -0,0 +1,25 @@ +clc
+L_A=0.003; //m
+L_B=0.05; //m
+L_C=L_A;
+
+k_A=46.5; //W/m 0C
+k_B=0.046; //W/m 0C
+k_C=k_A;
+h0=11.6; //W/m^2 0C
+hi=14.5; //W/m^2 0C
+t0=25; //0C
+ti=6; //0C
+
+A=0.5*0.5*2+0.5*1*4; //m^2
+
+disp("(i) The rate of removal of heat =")
+Q=A*(t0-ti)/(1/h0 + L_A/k_A + L_B/k_B + L_C/k_C + 1/hi);
+disp(Q)
+disp("W")
+
+
+disp("(ii) The temperature at the outer surface of the metal sheet =")
+t1=t0-Q/h0/A;
+disp(t1)
+disp("0C")
\ No newline at end of file diff --git a/551/CH15/EX15.8/8.sce b/551/CH15/EX15.8/8.sce new file mode 100755 index 000000000..514423067 --- /dev/null +++ b/551/CH15/EX15.8/8.sce @@ -0,0 +1,48 @@ +clc
+L_A=0.25; //m
+L_B=0.1; //m
+L_C=0.15; //m
+k_A=1.65; //W/m °C
+k_C=9.2; //W/m °C
+t_hf=1250; //°C
+t1=1100; //°C
+t_cf=25; //°C
+h_hf=25; //W/m^2 °C
+h_cf=12; //W/m^2 °C
+
+disp("(i) Thermal conductivity =")
+q=h_hf*(t_hf-t1);
+
+k_B=L_B/((t_hf-t_cf)/q-1/h_hf-L_A/k_A-L_C/k_C-1/h_cf);
+disp(" Thermal conductivity,k=")
+disp(k_B)
+disp("W/m^2 °C")
+
+
+disp("(ii) The overall transfer coefficient =")
+R_th_total=1/h_hf+L_A/k_A+L_B/k_B+L_C/k_C+1/h_cf;
+U=1/R_th_total;
+disp(U)
+disp("W/m^2 °C")
+
+
+disp("(iii) All surface temperature ")
+
+disp("t1=")
+disp(t1)
+disp("°C")
+
+t2=t1-q*L_A/k_A;
+disp("t2=")
+disp(t2)
+disp("°C")
+
+t3=t2-q*L_B/k_B;
+disp("t3=")
+disp(t3)
+disp("°C")
+
+t4=t3-q*L_C/k_C;
+disp("t4=")
+disp(t4)
+disp("°C")
\ No newline at end of file diff --git a/551/CH15/EX15.9/9.sce b/551/CH15/EX15.9/9.sce new file mode 100755 index 000000000..b9f55116c --- /dev/null +++ b/551/CH15/EX15.9/9.sce @@ -0,0 +1,12 @@ +clc
+r1=0.01; //m
+r2=0.02; //m
+r3=0.05; //m
+t1=600; //0C
+t3=1000; //0C
+k_B=0.2; //W/m 0C
+
+q=2*%pi*(t1-t3)/(log(r3/r2)/k_B);
+disp("Heat transfer per metre of length =")
+disp(q)
+disp("W/m")
\ No newline at end of file diff --git a/551/CH16/EX16.1/1.sce b/551/CH16/EX16.1/1.sce new file mode 100755 index 000000000..3cfc55924 --- /dev/null +++ b/551/CH16/EX16.1/1.sce @@ -0,0 +1,15 @@ +clc
+V1=300; //m/s
+p1=78; //kN/m^2
+T1=313; //K
+p2=117; //kN/m^2
+R=287; //J/kg K
+y=1.4;
+
+//Let r1=p1/rho1
+r1=R*T1;
+
+V2=sqrt(2*(y/(y-1)*r1*(1-(p2/p1)^((y-1)/y)) + V1^2/2));
+disp("Velocity of gas at section 2 =")
+disp(V2)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.10/10.sce b/551/CH16/EX16.10/10.sce new file mode 100755 index 000000000..c500e886a --- /dev/null +++ b/551/CH16/EX16.10/10.sce @@ -0,0 +1,24 @@ +clc
+R=287; //J/kg K
+y=1.4;
+p0=220*10^3; //N/m^2
+T0=300; //K
+V0=200; //m/s
+C0=sqrt(y*R*T0);
+rho_0=p0/R/T0;
+disp("Stagnation pressure =")
+
+disp("(i) Compressibility is neglected")
+ps=(p0+rho_0*V0^2/2)/10^3;
+disp("ps=")
+disp(ps)
+disp("kN/m^2")
+
+
+disp("(ii) Compressibility is accounted for")
+M0=V0/C0;
+
+ps=(p0+rho_0*V0^2/2*(1+M0^2/4+(2-y)/24*M0^4))/10^3;
+disp("ps=")
+disp(ps)
+disp("kN/m^2")
\ No newline at end of file diff --git a/551/CH16/EX16.11/11.sce b/551/CH16/EX16.11/11.sce new file mode 100755 index 000000000..e2166d16e --- /dev/null +++ b/551/CH16/EX16.11/11.sce @@ -0,0 +1,14 @@ +clc
+p0=35*10^3; //Pa
+T0=235; //K
+ps=65.4*10^3; //N/m^2
+R0=8314; //Nm/mole K
+M=28;
+
+R=R0/M;
+rho_0=p0/R/T0;
+
+Va=sqrt(2*(ps-p0)/rho_0);
+disp("Speed of the aircraft =")
+disp(Va)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.12/12.sce b/551/CH16/EX16.12/12.sce new file mode 100755 index 000000000..09cdae8e5 --- /dev/null +++ b/551/CH16/EX16.12/12.sce @@ -0,0 +1,19 @@ +clc
+p0=30*10^3; //N/m^2
+V0=152; //m/s
+y=1.4;
+
+rho_0=1.224; //kg/m^3
+ps=p0+rho_0*V0^2/2;
+
+rho_0=0.454; //kg/m^3
+V0=sqrt(2*(ps-p0)/rho_0);
+C0=sqrt(y*p0/rho_0);
+M=V0/C0;
+
+ccf=(1+M^2/4); //Compressibility correction factor
+
+V=V0/sqrt(ccf); //True speed of aircraft
+disp("True speed of aircraft =")
+disp(V)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.13/13.sce b/551/CH16/EX16.13/13.sce new file mode 100755 index 000000000..d79742a9e --- /dev/null +++ b/551/CH16/EX16.13/13.sce @@ -0,0 +1,22 @@ +clc
+M=3; //Mach number
+d=0.2; //m
+p_nozzle=7.85; //kN/m^2
+T_nozzle=200; //K
+y=1.4;
+A=%pi/4*d^2;
+
+disp("Reservoir pressure =")
+p_res=p_nozzle*(1+((y-1)/2*M^2))^(y/(y-1));
+disp(p_res)
+disp("kN/m^2")
+
+disp("Reservoir temperature =")
+T_res=T_nozzle*(1+((y-1)/2*M^2));
+disp(T_res)
+disp("K")
+
+disp("Throat area (critical) =")
+Ac=A*M/((2+(y-1)*M^2)/(y+1))^((y+1)/2/(y-1));
+disp(Ac)
+disp("m^2")
diff --git a/551/CH16/EX16.14/14.sce b/551/CH16/EX16.14/14.sce new file mode 100755 index 000000000..849651c64 --- /dev/null +++ b/551/CH16/EX16.14/14.sce @@ -0,0 +1,15 @@ +clc
+R=287; //J/kg K
+y=1.4;
+p_atm=100; //kN/m^2
+p1=284+p_atm; //kN/m^2
+T1=297; //K
+D=0.02; //m
+
+A2=%pi/4*D^2;
+rho_1=p1*10^3/R/T1;
+
+m_max=0.685*A2*sqrt(p1*10^3*rho_1);
+disp("Maximum flow rate =")
+disp(m_max)
+disp("kg/s")
\ No newline at end of file diff --git a/551/CH16/EX16.15/15.sce b/551/CH16/EX16.15/15.sce new file mode 100755 index 000000000..768d82087 --- /dev/null +++ b/551/CH16/EX16.15/15.sce @@ -0,0 +1,13 @@ +clc
+R=287; //J/kg K
+y=1.4;
+p1=2500*10^3; //N/m^2
+T1=293; //K
+p2=1750*10^3; //N/m^2
+
+rho_1=p1/R/T1;
+
+V2=sqrt(2*y/(y-1)*p1/rho_1*(1-(p2/p1)^((y-1)/y)));
+disp("Velocity of air =")
+disp(V2)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.16/16.sce b/551/CH16/EX16.16/16.sce new file mode 100755 index 000000000..02a6ddaae --- /dev/null +++ b/551/CH16/EX16.16/16.sce @@ -0,0 +1,31 @@ +clc
+R=287; //J/kg K
+y=1.4;
+p_atm=10^5; //N/m^2
+T1=293; //K
+D2=0.025; //m
+p1=140*10^3; //N/m^2
+
+A2=%pi/4*D2^2;
+
+disp("(i) Mass rate of flow of air when pressure in the tank is 140 kN/m2 (abs.)")
+rho_1=p1/R/T1;
+p2=10^5; //N/m^2
+
+m=A2*sqrt(2*y/(y-1)*p1*rho_1*((p2/p1)^(2/y) - (p2/p1)^((y+1)/y)));
+disp("m=")
+disp(m)
+disp("kg/s")
+
+
+disp("(ii) Mass rate of flow of air when pressure in the tank is 300 kN/m2 (abs.)")
+p1=300*10^3; //N/m^2
+p2=10^5; //N/m^2
+rho_1=p1/R/T1;
+
+disp("The pressure ratio p2/p1 being less than the critical ratio 0.528, the flow in the nozzle will be sonic");
+
+m_max=0.685*A2*sqrt(p1*rho_1);
+disp("m_max=")
+disp(m_max)
+disp("kg/s")
\ No newline at end of file diff --git a/551/CH16/EX16.17/17.sce b/551/CH16/EX16.17/17.sce new file mode 100755 index 000000000..e35abbda2 --- /dev/null +++ b/551/CH16/EX16.17/17.sce @@ -0,0 +1,72 @@ +clc
+p1=200; //kN/m^2
+V1=170; //m/s
+T1=473; //K
+A1=0.001; //m^2
+R=287; //J/kg K
+cp=1000; //J/kg K
+y=1.4;
+
+disp("(i) Stagnation temperature (Ts) and stagnation pressure (ps)")
+
+Ts=T1+V1^2/2/cp;
+disp("Ts=")
+disp(Ts)
+disp("K")
+
+ps=p1*(Ts/T1)^(y/(y-1));
+disp("ps=")
+disp(ps)
+disp("kN/m^2")
+
+
+disp("(ii) Sonic velocity and Mach number at this section")
+
+C1=sqrt(y*R*T1);
+disp("Sonic velocity =")
+disp(C1)
+disp("m/s")
+
+M1=V1/C1;
+disp("Mach number = ")
+disp(M1)
+
+
+disp("(iii) Velocity, Mach number and flow area at outlet section where pressure is 110 kN/m2")
+p2=110; //kN/m^2
+M2=sqrt(2/(y-1)*((ps/p2)^((y-1)/y) - 1));
+disp("M2=")
+disp(M2)
+
+T2=Ts*(p2/ps)^((y-1)/y);
+C2=sqrt(y*R*T2);
+V2=M2*C2;
+disp("V2=")
+disp(V2)
+disp("m/s")
+
+A2=(p1*A1*V1*T2/T1/p2/V2)*10^6;
+disp("A2=")
+disp(A2)
+disp("mm^2")
+
+
+disp("(iv) Pressure (pt), temperature (Tt), velocity (Vt), and flow area (At) at throat of the nozzle")
+Mt=1;
+Tt=Ts/(1+(y-1)/2*Mt^2);
+disp("Tt =")
+disp(Tt)
+disp("K")
+
+pt=ps*(Tt/Ts)^(y/(y-1));
+disp("pt")
+disp(pt)
+disp("kN/m^2")
+
+Ct=sqrt(y*R*Tt);
+Vt=Mt*Ct;
+
+At=(p1*A1*V1*Tt/T1/pt/Vt)*10^6;
+disp("At=")
+disp(At)
+disp("mm^2")
\ No newline at end of file diff --git a/551/CH16/EX16.18/18.sce b/551/CH16/EX16.18/18.sce new file mode 100755 index 000000000..3679770f3 --- /dev/null +++ b/551/CH16/EX16.18/18.sce @@ -0,0 +1,42 @@ +clc
+y=1.4;
+p1=26.5; //kN/m^2
+rho_1=0.413; //kg/m^3
+M1=2;
+R=287;
+
+M2=sqrt(((y-1)*M1^2 + 2)/(2*y*M1^2 - (y-1)));
+disp("Mach number M2=")
+disp(M2)
+
+p2=p1*(2*y*M1^2 - (y-1))/(y+1);
+disp("p2=")
+disp(p2)
+disp("kN/m^2")
+
+rho_2=rho_1*((y+1)*M1^2)/((y-1)*M1^2 + 2);
+disp("density, rho_2 =")
+disp(rho_2)
+disp("kg/m^3")
+
+T1=p1*10^3/rho_1/R;
+disp("T1=")
+disp(T1)
+disp("K")
+
+T2=T1*((y-1)*M1^2 + 2)*(2*y*M1^2 - (y-1))/((y+1)^2*M1^2);
+disp("T2=")
+disp(T2)
+disp("K")
+
+C1=sqrt(y*R*T1);
+V1=M1*C1;
+disp("V1=")
+disp(V1)
+disp("m/s")
+
+C2=sqrt(y*R*T2);
+V2=M2*C2;
+disp("V2 =")
+disp(V2)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.19/19.sce b/551/CH16/EX16.19/19.sce new file mode 100755 index 000000000..f096cf69f --- /dev/null +++ b/551/CH16/EX16.19/19.sce @@ -0,0 +1,25 @@ +clc
+M1=1.5;
+p1=170; //kN/m^2
+T1=296; //K
+y=1.4;
+
+disp("(i) Pressure, temperature and Mach number downstream of the shock")
+
+p2=p1*(2*y*M1^2 - (y-1))/(y+1);
+disp("p2=")
+disp(p2)
+disp("kN/m^2")
+
+T2=T1*((y-1)*M1^2 + 2)*(2*y*M1^2 - (y-1))/(y+1)^2/M1^2;
+disp("T2=")
+disp(T2)
+disp("K")
+
+M2=sqrt(((y-1)*M1^2 + 2)/(2*y*M1^2 - (y-1)));
+disp("M2=")
+disp(M2)
+
+strength=p2/p1 - 1;
+disp("Strength of stock =")
+disp(strength)
\ No newline at end of file diff --git a/551/CH16/EX16.2/2.sce b/551/CH16/EX16.2/2.sce new file mode 100755 index 000000000..aa856ca30 --- /dev/null +++ b/551/CH16/EX16.2/2.sce @@ -0,0 +1,21 @@ +clc
+p1=35; //kN/m^2
+V1=30; //m/s
+T1=423; //K
+V2=150; //m/s
+R=290; //J/kg K
+y=1.4;
+
+//Let r1=p2/p1
+r1=R*T1;
+
+p2=p1*(1-((V2^2/2-V1^2/2)*(y-1)/y/r1))^(y/(y-1));
+disp("p2=")
+disp(p2)
+disp("kN/m^2")
+
+T2=T1*(p2/p1)^((y-1)/y);
+t2=T2-273;
+disp("t2 =")
+disp(t2)
+disp("°C")
\ No newline at end of file diff --git a/551/CH16/EX16.3/3.sce b/551/CH16/EX16.3/3.sce new file mode 100755 index 000000000..f7725bf3b --- /dev/null +++ b/551/CH16/EX16.3/3.sce @@ -0,0 +1,16 @@ +clc
+SG=0.8;
+rho_oil=800; //kg/m^3
+K_oil=1.5*10^9; //N/m^2; crude oil
+K_Hg=27*10^9; //N/m^2; Mercury
+rho_Hg=13600; //kg/m^3
+
+C_oil=sqrt(K_oil/rho_oil);
+disp("Sonic velocity of crude oil =")
+disp(C_oil)
+disp("m/s")
+
+C_Hg=sqrt(K_Hg/rho_Hg)
+disp("Sonic velocity of Mercury =")
+disp(C_Hg)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.4/4.sce b/551/CH16/EX16.4/4.sce new file mode 100755 index 000000000..35c721dad --- /dev/null +++ b/551/CH16/EX16.4/4.sce @@ -0,0 +1,12 @@ +clc
+T=228; //K
+M=2;
+R=287; //Jkg K
+y=1.4;
+
+C=sqrt(y*R*T);
+
+V=M*C*3600/1000;
+disp("Velocity of the plane =")
+disp(V)
+disp("km/h")
\ No newline at end of file diff --git a/551/CH16/EX16.5/5.sce b/551/CH16/EX16.5/5.sce new file mode 100755 index 000000000..9f7f4b2a4 --- /dev/null +++ b/551/CH16/EX16.5/5.sce @@ -0,0 +1,12 @@ +clc
+a=40*%pi/180; //Mach angle in radians
+y=1.4;
+R=287; //J/kg K
+T=288; //K
+
+C=sqrt(y*R*T);
+
+V=C/sin(a);
+disp("Velocity of bullet =")
+disp(V)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.6/6.sce b/551/CH16/EX16.6/6.sce new file mode 100755 index 000000000..17e0a7154 --- /dev/null +++ b/551/CH16/EX16.6/6.sce @@ -0,0 +1,13 @@ +clc
+p=88.3; //kN/m^2
+T=271; //K
+M=40*%pi/180;
+y=1.4;
+R=287; //J/kg K
+
+C=sqrt(y*R*T);
+
+V=C/sin(M);
+disp("Velocity of the projectile =")
+disp(V)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH16/EX16.7/7.sce b/551/CH16/EX16.7/7.sce new file mode 100755 index 000000000..44bff3a2d --- /dev/null +++ b/551/CH16/EX16.7/7.sce @@ -0,0 +1,19 @@ +clc
+h=1800; //m
+T=277; //K
+t=4; //s
+y=1.4;
+R=287; //J/kg K
+
+C=sqrt(y*R*T);
+
+//tan(a)=h/t*V
+//V=C/sin(a)
+//From above two equations we get
+
+a=(acos(C/h*t));
+
+V=C/sin(a)*3600/1000;
+disp("Speed of the aircraft =")
+disp(V)
+disp("km/h")
\ No newline at end of file diff --git a/551/CH16/EX16.8/8.sce b/551/CH16/EX16.8/8.sce new file mode 100755 index 000000000..0429d6e73 --- /dev/null +++ b/551/CH16/EX16.8/8.sce @@ -0,0 +1,26 @@ +clc
+R=287; //J/kg K
+y=1.4;
+V0=1000*1000/3600; //m/s
+p0=78.5; //kN/m^2
+T0=265; //K
+
+C0=sqrt(y*R*T0);
+M0=V0/C0;
+
+disp("(i) Stagnation pressure =")
+ps=p0*(1+((y-1)/2*M0^2))^(y/(y-1));
+disp(ps)
+disp("kN/m^2")
+
+
+disp("(ii) Stagnation temperature =")
+Ts=T0*(1+((y-1)/2*M0^2));
+disp(Ts)
+disp("K")
+
+
+disp("(iii) Stagnation density =")
+rho_s=ps*10^3/R/Ts;
+disp(rho_s)
+disp("kg/m^3")
\ No newline at end of file diff --git a/551/CH16/EX16.9/9.sce b/551/CH16/EX16.9/9.sce new file mode 100755 index 000000000..4ede8c983 --- /dev/null +++ b/551/CH16/EX16.9/9.sce @@ -0,0 +1,34 @@ +clc
+V0=1000*1000/3600; //m/s
+T0=320; //K
+p_atm=98.1; //kN/m^2
+p=9.81; //kN/m^2
+p0=98.1-p;
+R=287; //J/kg K
+y=1.4;
+
+C0=sqrt(y*R*T0);
+M0=V0/C0;
+
+disp("Stagnation pressure =")
+ps=p0*(1+((y-1)/2*M0^2))^(y/(y-1));
+disp(ps)
+disp("kN/m^2")
+
+
+disp("Stagnation temperature =")
+Ts=T0*(1+((y-1)/2*M0^2));
+disp(Ts)
+disp("K")
+
+
+disp("Stagnation density =")
+rho_s=ps*10^3/R/Ts;
+disp(rho_s)
+disp("kg/m^3")
+
+M=0.8;
+
+CF=1+M0^2/4+(2-y)/24*M0^4;
+disp("Compressibility factor")
+disp(CF)
\ No newline at end of file diff --git a/551/CH2/EX2.1/1.sce b/551/CH2/EX2.1/1.sce new file mode 100755 index 000000000..61423bd0e --- /dev/null +++ b/551/CH2/EX2.1/1.sce @@ -0,0 +1,32 @@ +clc
+rho_Hg=13596; //kg/m^3
+g=9.806; //m/s^2
+h=0.76; //m
+
+P=rho_Hg*g*h/1000; //kPa
+
+disp("(i) Pressure of 80 cm of Hg")
+h1=0.80; //m
+P1=h1/h*P;
+disp(P1)
+disp("kPa")
+
+disp("(ii) 30 cm Hg vacuum")
+H2=0.30; //cm Hg vacuum
+h2=h-H2; //cm of Hg absolute
+disp("Pressure due to 46 cm of Hg")
+P2=h2/h*P;
+disp(P2)
+disp("kPa")
+
+disp("(iii) Pressure due to 1.35 m H2O gauge")
+rho_H2O=1000; //kg/m^3
+h3=1.35; //m
+P3=rho_H2O*g*h3/1000;
+disp(P3)
+disp("kPa")
+
+disp("(iv) 4.2 bar")
+P4=4.2*10^2;
+disp(P4)
+disp("kPa")
\ No newline at end of file diff --git a/551/CH2/EX2.10/10.sce b/551/CH2/EX2.10/10.sce new file mode 100755 index 000000000..4006af2c2 --- /dev/null +++ b/551/CH2/EX2.10/10.sce @@ -0,0 +1,9 @@ +clc
+v=800; //m/s
+g=9; //m/s^2
+F=3600; //N
+m=F/g;
+KE=1/2*m*v^2/10^6;
+disp("Kinetic Energy=")
+disp(KE)
+disp("MJ")
\ No newline at end of file diff --git a/551/CH2/EX2.11/11.sce b/551/CH2/EX2.11/11.sce new file mode 100755 index 000000000..abf977ce3 --- /dev/null +++ b/551/CH2/EX2.11/11.sce @@ -0,0 +1,16 @@ +clc
+m=6; //kg
+T1=25; //0C
+T2=125; //0C
+
+disp("(i) Heat transferred")
+Q=integrate('m*(0.4+0.004*T)','T',T1,T2);
+disp("heat tranferred=")
+disp(Q)
+disp("kJ")
+
+disp("(ii) Mean specific heat of the gas")
+c_n=Q/m/(T2-T1);
+disp("Mean specific heat=")
+disp(c_n)
+disp("kJ/kg.0C")
\ No newline at end of file diff --git a/551/CH2/EX2.12/12.sce b/551/CH2/EX2.12/12.sce new file mode 100755 index 000000000..7c5de98dd --- /dev/null +++ b/551/CH2/EX2.12/12.sce @@ -0,0 +1,18 @@ +clc
+Ice_point=0;
+Steam_point=100;
+// t=a*log(p)+b
+// from given conditions equations formed are
+// a*log(1.5)+b=0
+// a*log(7.5)+b=100
+// solving equations
+P=[log(1.5),1;log(7.5),1];
+Q=[0;100];
+X=inv(P)*Q;
+a=X(1,1);
+b=X(2,1);
+p=3.5;
+t=a*log(p)+b;
+disp("The value of temperature is given by")
+disp(t)
+disp("°C")
\ No newline at end of file diff --git a/551/CH2/EX2.13/13.sce b/551/CH2/EX2.13/13.sce new file mode 100755 index 000000000..1867579b8 --- /dev/null +++ b/551/CH2/EX2.13/13.sce @@ -0,0 +1,12 @@ +clc
+deff("[e]=func(t)","e=0.20*t-5*10^(-4)*t^2")
+t1=0; //0C
+e1=func(t1);
+t2=100; //0C
+e2=func(t2);
+t3=70; //0C
+e3=func(t3);
+t=e3*(t2-t1)/e2-e1;
+disp("thermocouple will read")
+disp(t)
+disp("°C")
\ No newline at end of file diff --git a/551/CH2/EX2.15/15.sce b/551/CH2/EX2.15/15.sce new file mode 100755 index 000000000..8f5d40719 --- /dev/null +++ b/551/CH2/EX2.15/15.sce @@ -0,0 +1,8 @@ +clc
+p=101.325; //kPa
+V2=0.6; //m^3
+V1=0; //m^3
+W=p*(V2-V1);
+disp("work done by atmosphere=")
+disp(-W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH2/EX2.16/16.sce b/551/CH2/EX2.16/16.sce new file mode 100755 index 000000000..80458b900 --- /dev/null +++ b/551/CH2/EX2.16/16.sce @@ -0,0 +1,8 @@ +clc
+p=1.013*10^5; //N/m^2
+V1=1.5; //m^3
+V2=0; //m^3
+W=p*(V2-V1);
+disp("W=")
+disp(W/10^3)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH2/EX2.17/17.sce b/551/CH2/EX2.17/17.sce new file mode 100755 index 000000000..22257a89b --- /dev/null +++ b/551/CH2/EX2.17/17.sce @@ -0,0 +1,13 @@ +clc
+T=1.25; //N.m
+N=9500;
+W1=2*%pi*N*T/1000; //kJ
+p=101.3; //kPa
+d=0.65; //m
+A=%pi/4*d^2; //m^2
+L=0.6; //m
+W2=p*A*L; //kJ
+Wnet=(-W1)+W2;
+disp("The net work transfer for the system=")
+disp(Wnet)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH2/EX2.18/18.sce b/551/CH2/EX2.18/18.sce new file mode 100755 index 000000000..d44266a0c --- /dev/null +++ b/551/CH2/EX2.18/18.sce @@ -0,0 +1,10 @@ +clc
+A=45*10^(-4); //m^2
+P=0.9*10^5; //N/m^2
+Patm=1.013*10^5; //N/m^2
+L=0.05; //m
+dV=300*10^(-6); //m^3
+W=P*A*L-Patm*dV;
+disp("net work done =")
+disp(W)
+disp("J")
\ No newline at end of file diff --git a/551/CH2/EX2.19/19.sce b/551/CH2/EX2.19/19.sce new file mode 100755 index 000000000..2088479ff --- /dev/null +++ b/551/CH2/EX2.19/19.sce @@ -0,0 +1,9 @@ +clc
+p1=1.5; //bar
+p2=7.5; //bar
+V1=3/p1;
+V2=3/p2;
+W=integrate('3/V*10^2', 'V', V1, V2);
+disp("Work done=")
+disp(W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH2/EX2.2/2.sce b/551/CH2/EX2.2/2.sce new file mode 100755 index 000000000..0450ca1c7 --- /dev/null +++ b/551/CH2/EX2.2/2.sce @@ -0,0 +1,8 @@ +clc
+d=0.1; //m
+F=1000; //N
+A=%pi/4*d^2; //m^2
+P=F/A/10^3;
+disp("Pressure on the piston=")
+disp(P)
+disp("kN/m^2")
\ No newline at end of file diff --git a/551/CH2/EX2.20/20.sce b/551/CH2/EX2.20/20.sce new file mode 100755 index 000000000..46d4eced6 --- /dev/null +++ b/551/CH2/EX2.20/20.sce @@ -0,0 +1,17 @@ +clc +W=150; //kJ +V1=0.6; //m^3 + +// p=8-4*V +// W=integration of p*dV from V1 to V2 +// Solving above equation we get + +V2=0.354; //m^3 +disp("Final volume =") +disp(V2) +disp("m^3") + +p2=8-4*V2; +disp("Final pressure =") +disp(p2) +disp("bar")
\ No newline at end of file diff --git a/551/CH2/EX2.21/21.sce b/551/CH2/EX2.21/21.sce new file mode 100755 index 000000000..59f3b8ff7 --- /dev/null +++ b/551/CH2/EX2.21/21.sce @@ -0,0 +1,10 @@ +clc +p1=3*10^5; //Pa +v1=0.18; //m^3/kg +C=p1*v1^2; +p2=0.6*10^5; //Pa +v2=sqrt(C/p2); +W=integrate('C/v^2', 'v', v1,v2); +disp("Work done=") +disp(W) +disp("Nm/kg")
\ No newline at end of file diff --git a/551/CH2/EX2.22/22.sce b/551/CH2/EX2.22/22.sce new file mode 100755 index 000000000..bf9566c16 --- /dev/null +++ b/551/CH2/EX2.22/22.sce @@ -0,0 +1,16 @@ +clc +m=1; //kg +p1=20*10^5; //Pa +V1=0.05; //m^3 +V2=2*V1; +p2=p1*(V1/V2)^2; +C=p1*V1^2; +V3=V1; +W_12=integrate('C/V^2', 'V', V1,V2); + +W_23=p2*(V2-V3); + +W_net=W_12-W_23; +disp("Net work done = ") +disp(W_net) +disp("Nm")
\ No newline at end of file diff --git a/551/CH2/EX2.3/3.sce b/551/CH2/EX2.3/3.sce new file mode 100755 index 000000000..e10a58ff9 --- /dev/null +++ b/551/CH2/EX2.3/3.sce @@ -0,0 +1,10 @@ +clc
+SG=0.9;
+h=1.2; //m
+g=9.81; //m/s^2
+rho_w=1000; //kg/m^3
+rho=SG*rho_w; //kg/m^3
+P=rho*g*h/10^3;
+disp("Gauge pressure P=")
+disp(P)
+disp("kN/m^2")
\ No newline at end of file diff --git a/551/CH2/EX2.4/4.sce b/551/CH2/EX2.4/4.sce new file mode 100755 index 000000000..341064f2f --- /dev/null +++ b/551/CH2/EX2.4/4.sce @@ -0,0 +1,8 @@ +clc
+Vacuum_recorded=740; //mm of Hg
+Barometric_reading=760; //mm of Hg
+
+Absolute_pressure=(Barometric_reading-Vacuum_recorded)*133.4;
+disp("Absolute pressure in the condenser=")
+disp(Absolute_pressure)
+disp("Pa")
\ No newline at end of file diff --git a/551/CH2/EX2.5/5.sce b/551/CH2/EX2.5/5.sce new file mode 100755 index 000000000..70f12096d --- /dev/null +++ b/551/CH2/EX2.5/5.sce @@ -0,0 +1,22 @@ +clc
+d=0.5; //m
+h=0.75; //m
+m=4; //kg
+Manometer_reading=620; //mm of Hg above atmosphere
+Barometer_reading=760; //mm of Hg
+V=%pi/4*d^2*h; //m^3
+disp("(i) Total pressure in the vessel")
+
+P=(Barometer_reading+Manometer_reading)*133.4/10^5; //bar
+disp("P=")
+disp(P)
+disp("bar")
+disp("(ii) Specific volume and density")
+SV=V/m;
+disp("Specific volume=")
+disp(SV)
+disp("m^3/kg")
+D=m/V;
+disp("Density=")
+disp(D)
+disp("kg/m^3")
\ No newline at end of file diff --git a/551/CH2/EX2.6/6.sce b/551/CH2/EX2.6/6.sce new file mode 100755 index 000000000..e71b5b06e --- /dev/null +++ b/551/CH2/EX2.6/6.sce @@ -0,0 +1,9 @@ +clc
+h0=.761; //m
+h=.55; //m
+g=9.79; //m/s^2
+rho=13640; //kg/m^3
+P=rho*g*(h0+h); //N/m^2
+disp("Gas pressure=")
+disp(P/10^5)
+disp("bar")
\ No newline at end of file diff --git a/551/CH2/EX2.7/7.sce b/551/CH2/EX2.7/7.sce new file mode 100755 index 000000000..35d071c5e --- /dev/null +++ b/551/CH2/EX2.7/7.sce @@ -0,0 +1,11 @@ +clc
+h_H2O=34; //mm of Hg
+g=9.81; //m/s^2
+rho=13600; //kg/m^3
+P_Hg=97.5; //mm of Hg
+P_atm=760; //mm of Hg
+P_H2O=h_H2O/13.6; //mm of Hg
+Pabs=rho*g*(P_Hg+P_atm-P_H2O)/10^8; //bar
+disp("absolute pressure =")
+disp(Pabs)
+disp("bar")
\ No newline at end of file diff --git a/551/CH2/EX2.8/8.sce b/551/CH2/EX2.8/8.sce new file mode 100755 index 000000000..bb50fc5fa --- /dev/null +++ b/551/CH2/EX2.8/8.sce @@ -0,0 +1,12 @@ +clc
+SG=0.8;
+rho_H2O=1000; //kg/m^3
+g=9.81; //ms^2
+h=0.17; //m
+Patm=1.01325; //bar
+rho=SG*rho_H2O; //kg/m^3
+P_liq=rho*g*h/10^5; //bar
+P_gas=Patm - P_liq;
+disp("gas pressure= ")
+disp(P_gas)
+disp("bar")
\ No newline at end of file diff --git a/551/CH2/EX2.9/9.sce b/551/CH2/EX2.9/9.sce new file mode 100755 index 000000000..8d9955ad6 --- /dev/null +++ b/551/CH2/EX2.9/9.sce @@ -0,0 +1,10 @@ +clc
+d=0.2; //m
+g=9.81; //m/s^2
+h=0.117; //m
+rho=13600; //kg/m^3
+p=rho*g*h;
+m=(p*%pi/4*d^2)/g;
+disp("mass=")
+disp(m)
+disp("kg")
\ No newline at end of file diff --git a/551/CH3/EX3.1/1.sce b/551/CH3/EX3.1/1.sce new file mode 100755 index 000000000..d09fbdde9 --- /dev/null +++ b/551/CH3/EX3.1/1.sce @@ -0,0 +1,6 @@ +clc
+m_s=50; //kg
+m_w=1.5; //kg
+x=m_s/(m_s+m_w);
+disp("dryness fraction=")
+disp(x)
\ No newline at end of file diff --git a/551/CH3/EX3.10/10.sce b/551/CH3/EX3.10/10.sce new file mode 100755 index 000000000..49d785811 --- /dev/null +++ b/551/CH3/EX3.10/10.sce @@ -0,0 +1,44 @@ +clc
+V=0.9; //m^3
+p1=8; //bar
+x1=0.9;
+p2=4; //bar
+p3=3; //bar
+v_g1=0.24; //m^3/kg
+
+disp("(i) The mass of steam blown off :")
+m1=V/x1/v_g1;
+h_f1=720.9; //kJ/kg
+h_fg1=2046.5; //kJ/kg
+h_f2=604.7; //kJ/kg
+h_fg2=2133; //kJ/kg
+v_g2=0.462; //m^3/kg
+
+h1=h_f1+x1*h_fg1; //The enthalpy of steam before blowing off
+
+h2=h1;
+x2=(h1-h_f2)/h_fg2;
+m2=x1/(x2*v_g2);
+
+disp("Mass of steam blown off =")
+m=m1-m2;
+disp(m)
+disp("kg")
+
+disp("(ii) Dryness fraction of steam in the vessel after cooling")
+v_g3=0.606; //m^3/kg
+x3=x2*v_g2/v_g3;
+disp("dryness fraction =")
+disp(x3)
+
+
+disp("(iii) Heat lost during cooling")
+h_f3=561.4; //kJ/kg
+h_fg3=2163.2; //kJ/kg
+h3=h_f3+x3*h_fg3;
+u2=h2-p2*x2*v_g2*10^2; //kJ/kg
+u3=h3-p3*x3*v_g3*10^2; //kJ/kg
+Q=m*(u3-u2);
+disp("Heat lost during cooling=")
+disp(-Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.11/11.sce b/551/CH3/EX3.11/11.sce new file mode 100755 index 000000000..21231b96b --- /dev/null +++ b/551/CH3/EX3.11/11.sce @@ -0,0 +1,18 @@ +clc
+p=8*10^5; //Pa
+x=0.8;
+
+v_g=0.240; //m^3/kg
+h_fg=2046.5; //kJ/kg
+
+disp("(i) External work done during evaporation")
+W=p*x*v_g/10^3; //kJ
+disp("W=")
+disp(W)
+disp("kJ")
+
+disp("(ii) Internal latent heat")
+Q=x*h_fg-W;
+disp("Q=")
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.12/12.sce b/551/CH3/EX3.12/12.sce new file mode 100755 index 000000000..22c2520a6 --- /dev/null +++ b/551/CH3/EX3.12/12.sce @@ -0,0 +1,25 @@ +clc
+p1=10; //bar
+p2=10; //bar
+x1=0.85;
+V1=0.15; //m^3
+t_sup2=300; //0C
+t_sup1=179.9; //0C
+c_ps=2.2; //kJ/kg.K
+v_g1=0.194; //m^3/kg
+m=V1/(x1*v_g1);
+h_fg1=2013.6; //kJ/kg
+Q=(1-x1)*h_fg1+c_ps*(t_sup2-t_sup1);
+Q_total=m*Q;
+
+disp("Total heat supplied=")
+disp(Q_total)
+disp("kJ")
+
+v_sup2=v_g1*(t_sup2+273)/(t_sup1+273)
+W=p1*(v_sup2 - (x1*v_g1))*10^2;
+Percentage=W/Q*100;
+
+disp("Percentage of total heat supplied=")
+disp(Percentage)
+disp("%")
\ No newline at end of file diff --git a/551/CH3/EX3.13/13.sce b/551/CH3/EX3.13/13.sce new file mode 100755 index 000000000..e6ee81014 --- /dev/null +++ b/551/CH3/EX3.13/13.sce @@ -0,0 +1,21 @@ +clc
+p=18; //bar
+x=0.85;
+h_f=884.6; //kJ/kg
+h_fg=1910.3; //kJ/kg
+v_g=0.110; //m^3/kg
+u_f=883; //kJ/kg
+u_g=2598; //kJ/kg
+v=x*v_g;
+disp("Specific volume of wet steam=")
+disp(v)
+disp("m^3/kg")
+
+h=h_f+x*h_fg;
+disp("Specific enthalpy of wet steam=")
+disp(h)
+disp("kJ/kg")
+u=(1-x)*u_f+ x*u_g;
+disp("Specific internal energy of wet steam =")
+disp(u)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH3/EX3.14/14.sce b/551/CH3/EX3.14/14.sce new file mode 100755 index 000000000..3a9e30714 --- /dev/null +++ b/551/CH3/EX3.14/14.sce @@ -0,0 +1,21 @@ +clc
+p=7; //bar
+h=2550; //kJ/kg
+h_f=697.1; //kJ/kg
+h_fg=2064.9; //kJ/kg
+v_g=0.273; //m^3/kg
+u_f=696; //kJ/kg
+u_g=2573; //kJ/kg
+x=(h-h_f)/h_fg;
+disp("(i) Dryness fraction=")
+disp(x)
+
+v=x*v_g;
+disp("(ii) Specific volume of wet steam =")
+disp(v)
+disp("m^3/kg")
+
+u=(1-x)*u_f+ x*u_g;
+disp("(iii) Specific internal energy of wet steam=")
+disp(u)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH3/EX3.15/15.sce b/551/CH3/EX3.15/15.sce new file mode 100755 index 000000000..1976725e3 --- /dev/null +++ b/551/CH3/EX3.15/15.sce @@ -0,0 +1,18 @@ +clc
+p=120; //bar
+v=0.01721; //m^3/kg
+
+T=350; //°C
+disp("Temperature=")
+disp(T)
+disp("°C")
+
+h=2847.7; //kJ/kg
+disp("specific enthalpy=")
+disp(h)
+disp("kJ/kg")
+
+u=h-p*v*10^2; //kJ/kg
+disp("Internal energy=")
+disp(u)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH3/EX3.16/16.sce b/551/CH3/EX3.16/16.sce new file mode 100755 index 000000000..0d3043347 --- /dev/null +++ b/551/CH3/EX3.16/16.sce @@ -0,0 +1,18 @@ +clc
+p=140; //bar
+h=3001.9; //kJ/kg
+
+T=400; //0C
+disp("Temperature=")
+disp(T)
+disp("°C")
+
+v=0.01722; //m^3/kg
+disp("The specific volume")
+disp(v)
+disp("m^3/kg")
+
+u=h-p*v*10^2;
+disp("specific internal energy=")
+disp(u)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH3/EX3.17/17.sce b/551/CH3/EX3.17/17.sce new file mode 100755 index 000000000..e71f85835 --- /dev/null +++ b/551/CH3/EX3.17/17.sce @@ -0,0 +1,26 @@ +clc
+// At 10 bar: From steam table for superheated steam
+h_sup=3051.2; //kJ/kg
+T_sup=573; //K
+T_s=452.9; //K
+v_g=0.194; //m^3/kg
+v_sup=v_g*T_sup/T_s;
+p=10; //bar
+
+u1=h_sup-p*v_sup*10^2; //kJ/kg
+disp("Internal energy of superheated steam at 10 bar= ")
+disp(u1)
+disp("kJ/kg")
+
+// At 1.4 bar: From steam tables
+p=1.4; //bar
+h_f=458.4; //kJ/kg
+h_fg=2231.9; //kJ/kg
+v_g=1.236; //m^3/kg
+x=0.8;
+h=h_f+x*h_fg;
+u2=h-p*x*v_g*10^2; //kJ
+du=u2-u1;
+disp("Change in internal energy=")
+disp(du)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.18/18.sce b/551/CH3/EX3.18/18.sce new file mode 100755 index 000000000..461b5dadd --- /dev/null +++ b/551/CH3/EX3.18/18.sce @@ -0,0 +1,26 @@ +clc
+m=1; //kg
+p=20; //bar
+T_sup=400; //0C
+x=0.9;
+c_ps=2.3; //kJ/kg.K
+
+disp("(i) Internal energy of 1 kg of superheated steam")
+// At 20 bar: From steam tables
+T_s=212.4; //0C
+h_f=908.6; //kJ/kg
+h_fg=1888.6; //kJ/kg
+v_g=0.0995; //m^3/kg
+h_sup = h_f+h_fg+c_ps*(T_sup-T_s);
+v_sup=v_g*(T_sup+273)/(T_s+273);
+u=h_sup-p*v_sup*10^2;
+disp("Internal energy=")
+disp(u)
+disp("kJ/kg")
+
+disp("(ii) Internal energy of 1 kg of wet steam")
+h=h_f+x*h_fg;
+u=h-p*x*v_g*10^2;
+disp("Internal energy=")
+disp(u)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH3/EX3.19/19.sce b/551/CH3/EX3.19/19.sce new file mode 100755 index 000000000..1ec6d28c1 --- /dev/null +++ b/551/CH3/EX3.19/19.sce @@ -0,0 +1,15 @@ +clc
+h_g1=2797.2; //kJ/kg
+c_ps= 2.25;
+T_sup=350; //0C
+T_s=212.4; //0C
+h1=h_g1+c_ps*(T_sup-T_s);
+h_f2=908.6; //kJ/kg
+h_fg2=1888.6; //kJ/kg
+
+// Main:20 bar, 250 0C
+T_sup=250; //0C
+Q=2*[h_g1+c_ps*(T_sup-T_s)];
+x2=(Q-h1-h_f2)/h_fg2;
+disp("Quality of steam")
+disp(x2)
\ No newline at end of file diff --git a/551/CH3/EX3.2/2.sce b/551/CH3/EX3.2/2.sce new file mode 100755 index 000000000..923337428 --- /dev/null +++ b/551/CH3/EX3.2/2.sce @@ -0,0 +1,30 @@ +clc
+V=0.6; //m^3
+m=3.0; //kg
+p=5; //bar
+v=V/m;
+// At 5 bar: From steam tables
+v_g=0.375; //m^3/kg
+v_f=0.00109; //m^3/kg
+v_fg=v_g - v_f;
+x=1-((v_g - v)/v_fg);
+
+disp("(i) Mass and volume of liquid")
+m_liq=m*(1-x);
+disp("mass of liquid=")
+disp(m_liq)
+disp("kg")
+V_liq=m_liq*v_f;
+disp("volume of liquid=")
+disp(V_liq)
+disp("m^3")
+
+disp("(ii) Mass and volume of vapour")
+m_vap=m*x;
+disp("mass of vapour=")
+disp(m_vap)
+disp("kg")
+V_vap=m_vap*v_g;
+disp("volume of vapour=")
+disp(V_vap)
+disp("m^3")
\ No newline at end of file diff --git a/551/CH3/EX3.20/20.sce b/551/CH3/EX3.20/20.sce new file mode 100755 index 000000000..f0a38fb11 --- /dev/null +++ b/551/CH3/EX3.20/20.sce @@ -0,0 +1,11 @@ +clc
+m=1; //kg
+p=6; //bar
+x=0.8;
+T_s=473; //K
+h_fg=2085; //kJ/kg
+c_pw=4.18;
+s_wet=c_pw*log(T_s/273)+x*h_fg/T_s;
+disp("Entropy of wet steam=")
+disp(s_wet)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH3/EX3.21/21.sce b/551/CH3/EX3.21/21.sce new file mode 100755 index 000000000..883f60eab --- /dev/null +++ b/551/CH3/EX3.21/21.sce @@ -0,0 +1,29 @@ +clc
+p1=10; //bar
+t_sup=400; //0C
+p2=0.2; //bar
+x2=0.9;
+h_sup=3263.9; //kJ/kg
+s_sup=7.465; //kJ/kg
+h1=3263.9; //kJ/kg
+s1=s_sup;
+h_f2=251.5; //kJ/kg
+h_fg2=2358.4; //kJ/kg
+s_f2=0.8321; //kJ/kg.K
+s_g2=7.9094; //kJ/kg.K
+s_fg2=s_g2-s_f2;
+h2=h_f2+x2*h_fg2;
+s2=s_f2+x2*s_fg2;
+
+disp("(i) Drop in enthalpy")
+dh=h1-h2;
+disp("Drop in enthalpy = ")
+disp(dh)
+disp("kJ/kg")
+
+
+disp("(ii) Change in entropy")
+ds=s1-s2;
+disp("Change in entropy = ")
+disp(ds)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH3/EX3.22/22.sce b/551/CH3/EX3.22/22.sce new file mode 100755 index 000000000..ddab1bf4a --- /dev/null +++ b/551/CH3/EX3.22/22.sce @@ -0,0 +1,12 @@ +clc
+m=1; //kg
+p=12; //bar
+T_sup=523; //K
+c_ps=2.1; //kJ/kg.K
+T_s=461; //K
+h_fg=1984.3; //kJ/kg
+c_pw=4.18;
+s_sup=c_pw*log(T_s/273)+h_fg/T_s+c_ps*log(T_sup/T_s);
+disp("Entropy =")
+disp(s_sup)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH3/EX3.23/23.sce b/551/CH3/EX3.23/23.sce new file mode 100755 index 000000000..b7e5b7332 --- /dev/null +++ b/551/CH3/EX3.23/23.sce @@ -0,0 +1,29 @@ +clc
+m=3; //kg
+v1=0.75; //m^3/kg
+v2=1.2363; //m^3/kg
+x=v1/v2;
+h_f=458.4; //kJ/kg
+h_fg=2231.9; //kJ/kg
+h_s=m*[h_f+x*h_fg]; //kJ
+v_sup=1.55; //m^3/kg
+p=2; //bar
+t_s=120.2; //0C
+t_sup=400; //0C
+h=3276.6; //kJ/kg
+U=1708; //kJ/kg
+Degree=t_sup-t_s;
+h_sup=m*h;
+
+Q_added=h_sup - h_s;
+disp("Heat added =")
+disp(Q_added)
+disp("kJ")
+
+U_s=m*U;
+U_sup=m*(h-p*v_sup*10^2);
+dU= U_sup - U_s;
+W=Q_added - dU;
+disp("work done = ")
+disp(W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.24/24.sce b/551/CH3/EX3.24/24.sce new file mode 100755 index 000000000..f6c0e6490 --- /dev/null +++ b/551/CH3/EX3.24/24.sce @@ -0,0 +1,14 @@ +clc
+p=5; //bar
+m=50; //kg
+T1=20; //0C
+m_s=3; //kg
+T2=40; //0C
+m_eq=1.5; //kg
+h_f=640.1; //kJ/kg
+h_fg=2107.4; //kJ/kg
+c_pw=4.18;
+m_w=m+m_eq;
+x=[(m_w*c_pw*(T2-T1))/m_s + c_pw*T2 - h_f]/h_fg;
+disp("Dryness fraction of steam")
+disp(x)
\ No newline at end of file diff --git a/551/CH3/EX3.25/25.sce b/551/CH3/EX3.25/25.sce new file mode 100755 index 000000000..3de31da00 --- /dev/null +++ b/551/CH3/EX3.25/25.sce @@ -0,0 +1,15 @@ +clc
+p=1.1; //bar
+x=0.95;
+c_pw=4.18;
+m1=90; //kg
+m2=5.25; //kg
+T1=25; //0C
+T2=40; //0C
+m=m1+m2;
+h_f=428.8; //kJ/kg
+h_fg= 2250.8; //kJ/kg
+m_s= [m*c_pw*(T2-T1)]/[(h_f + x*h_fg) - c_pw*T2];
+disp("Mass of steam condensed=")
+disp(m_s)
+disp("kg")
\ No newline at end of file diff --git a/551/CH3/EX3.26/26.sce b/551/CH3/EX3.26/26.sce new file mode 100755 index 000000000..c5dcadb1c --- /dev/null +++ b/551/CH3/EX3.26/26.sce @@ -0,0 +1,13 @@ +clc
+p1=8; //bar
+p2=1; //bar
+T_sup2=115; //0C
+T_s2=99.6; //0C
+h_f1=720.9; //kJ/kg
+h_fg1=2046.5; //kJ/kg
+h_f2=417.5; //kJ/kg
+h_fg2=2257.9; //kJ/kg
+c_ps=2.1;
+x1=[h_f2+h_fg2+c_ps*(T_sup2-T_s2)-h_f1]/h_fg1;
+disp("Dryness fraction of the steam in the main = ")
+disp(x1)
\ No newline at end of file diff --git a/551/CH3/EX3.27/27.sce b/551/CH3/EX3.27/27.sce new file mode 100755 index 000000000..1369d6afb --- /dev/null +++ b/551/CH3/EX3.27/27.sce @@ -0,0 +1,18 @@ +clc
+m_w=2; //kg
+m_s=20.5; //kg
+t_sup=110; //0C
+p1=12; //bar
+p3=1; //bar
+p2=p1;
+h_f2=798.4; //kJ/kg
+h_fg2=1984.3; //kJ/kg
+T_s=99.6; //0C
+h_f3=417.5; //kJ/kg
+h_fg3=2257.9; //kJ/kg
+T_sup=110; //0C
+c_ps=2; //kJ/kg.K
+x2=[h_f3+h_fg3 + c_ps*(T_sup-T_s) - h_f2]/h_fg2;
+x1=x2*m_s/(m_w+m_s);
+disp("Quality of steam supplied = ")
+disp(x1)
\ No newline at end of file diff --git a/551/CH3/EX3.28/28.sce b/551/CH3/EX3.28/28.sce new file mode 100755 index 000000000..7d858f193 --- /dev/null +++ b/551/CH3/EX3.28/28.sce @@ -0,0 +1,14 @@ +clc
+p1=15; //bar
+p2=p1;
+p3=1; //bar
+t_sup3=150; //0C
+m_w=0.5; //kg/min
+m_s=10; //kg/min
+h_f2=844.7; //kJ/kg
+h_fg2=1945.2; //kJ/kg
+h_sup3=2776.4; //kJ/kg
+x2=(h_sup3 - h_f2)/h_fg2;
+x1=x2*m_s/(m_s + m_w);
+disp("Quality of steam supplied = ")
+disp(x1)
\ No newline at end of file diff --git a/551/CH3/EX3.3/3.sce b/551/CH3/EX3.3/3.sce new file mode 100755 index 000000000..ea361ba33 --- /dev/null +++ b/551/CH3/EX3.3/3.sce @@ -0,0 +1,50 @@ +clc
+V=0.05; //m^3
+m_f=10; //kg
+// From steam tables corresponding to 245 0C
+p_sat=36.5; //bar
+v_f=0.001239; //m^3/kg
+v_g=0.0546; //m^3/kg
+h_f=1061.4; //kJ/kg
+h_fg=1740.2; //kJ/kg
+s_f=2.7474; //kJ/kg.K
+s_fg=3.3585; //kJ/kg.K
+
+disp("(i) The pressure=")
+disp(p_sat)
+disp("bar")
+
+disp("(ii) The mass")
+V_f=m_f*v_f;
+V_g=V - V_f;
+m_g=V_g/v_g;
+m=m_f+m_g;
+disp("The total mass of mixture=")
+disp(m)
+disp("kg")
+
+disp("(iii) The specific volume")
+v_fg=v_g-v_f;
+x= m_g/(m_g+ m_f);
+v=v_f+x*v_fg;
+disp("specific volume=")
+disp(v)
+disp("m^3/kg")
+
+disp("(iv)The specific enthalpy")
+h=h_f+x*h_fg;
+disp("specific enthalpy=")
+disp(h)
+disp("kJ/kg")
+
+disp("(v)The specific entropy")
+s=s_f+x*s_fg;
+disp("specific entropy =")
+disp(s)
+disp("kJ/kg.K")
+
+disp("(vi)The specific internal enegy")
+u=h-(p_sat*v*10^2); //kJ/kg
+disp("specific internal energy=")
+disp(u)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH3/EX3.4/4.sce b/551/CH3/EX3.4/4.sce new file mode 100755 index 000000000..6c275a32b --- /dev/null +++ b/551/CH3/EX3.4/4.sce @@ -0,0 +1,23 @@ +clc
+m_w=2; //kg
+t_w=25; //0C
+p=5; //bar
+x=0.9;
+c_pw=4.18;
+// at 5 bar; from steam tables
+h_f=640.1; //kJ/kg
+h_fg=2107.4; //kJ/kg
+h=h_f+x*h_fg;
+disp("Sensible heat associated with 1kg of water, Qw=")
+Qw=c_pw*(t_w-0);
+disp(Qw)
+disp("kJ")
+disp("Net quantity of heat to be supplies per kg of water, Q=")
+Q=h-Qw;
+disp(Q)
+disp("kJ")
+
+disp("Total amount of heat supplied, Q_total=")
+Q_total=m_w*Q;
+disp(Q_total)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.5/5.sce b/551/CH3/EX3.5/5.sce new file mode 100755 index 000000000..99c7285e5 --- /dev/null +++ b/551/CH3/EX3.5/5.sce @@ -0,0 +1,25 @@ +clc
+m=4.4; //kg
+p=6; //bar
+t_sup=250; //0C
+t_w= 30; //0C
+c_ps=2.2; //kJ/kg
+c_pw=4.18;
+// At 6 bar, 250 0C; From steam tables
+t_s=158.8; //0C
+h_f=670.4; //kJ/kg
+h_fg=2085; //kJ/kg
+h_sup=h_f+h_fg+ c_ps*(t_sup-t_s);
+
+disp("Amount of heat added per kg of water, Qw=")
+Qw=c_pw*(t_w-0);
+disp(Qw)
+
+disp("Net amount of heat required to be supplied per kg, Q=")
+Q=h_sup-Qw;
+disp(Q)
+
+disp("Total amount of heat required, Q_total=")
+Q_total=m*Q;
+disp(Q_total)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.6/6.sce b/551/CH3/EX3.6/6.sce new file mode 100755 index 000000000..f3ffa0e0c --- /dev/null +++ b/551/CH3/EX3.6/6.sce @@ -0,0 +1,18 @@ +clc
+v=0.15; //m^3
+p=4; //bar
+x=0.8;
+// At 4 bar: From steam tables
+v_g=0.462; //m^3/kg
+h_f= 604.7; //kJ/kg
+h_fg=2133; //kJ/kg
+density=1/x/v_g;
+disp("mass of 0.15 m^3 steam, m=")
+m=v*density;
+disp(m)
+disp("kg")
+
+disp("Total heat of 1 m3 of steam which has a mass of 2.7056 kg, Q=")
+Q=density*(h_f+x*h_fg);
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.7/7.sce b/551/CH3/EX3.7/7.sce new file mode 100755 index 000000000..0e79ab594 --- /dev/null +++ b/551/CH3/EX3.7/7.sce @@ -0,0 +1,22 @@ +clc
+m=1000; //kJ/kg.K
+p=16; //bar
+x=0.9;
+T_sup=653; //K
+T_w=30; //0C
+c_ps=2.2; //kJ/kg
+c_pw=4.18;
+// At 16 bar:From steam tables
+T_s=474.4; //K
+h_f=858.6; //kJ/kg
+h_fg=1933.2; //kJ/kg
+
+disp("(i) Heat supplied to feed water per hour to produce wet steam is given by")
+H=m*[(h_f+x*h_fg)-c_pw*(T_w-0)];
+disp(H)
+disp("kJ")
+
+disp("(ii) Heat absorbed by superheater per hour, Q=")
+Q=m*[(1-x)*h_fg+c_ps*(T_sup-T_s)];
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH3/EX3.8/8.sce b/551/CH3/EX3.8/8.sce new file mode 100755 index 000000000..cbdd850e5 --- /dev/null +++ b/551/CH3/EX3.8/8.sce @@ -0,0 +1,23 @@ +clc
+
+disp("(i) at 0.75 bar, between 100°C and 150°C")
+// At 100 °C
+T1=100; //°C
+h_sup1=2679.4; //kJ/kg
+// At 150 °C
+T2=150; //°C
+h_sup2=2778.2; //kJ/kg
+
+c_ps=(h_sup2-h_sup1)/(T2-T1);
+disp("mean specific heat=")
+disp(c_ps)
+
+disp("(ii) at 0.5 bar, between 300°C and 400°C")
+T1=300; //°C
+h_sup1=3075.5; //kJ/kg
+T2=400; //°C
+h_sup2=3278.9; //kJ/kg
+
+c_ps=(h_sup2-h_sup1)/(T2-T1);
+disp("mean specific heat c_ps=")
+disp(c_ps)
\ No newline at end of file diff --git a/551/CH3/EX3.9/9.sce b/551/CH3/EX3.9/9.sce new file mode 100755 index 000000000..aca51357b --- /dev/null +++ b/551/CH3/EX3.9/9.sce @@ -0,0 +1,37 @@ +clc
+m=1.5; //kg
+p=5; //bar
+x1=1;
+x2=0.6;
+p1=5*10^5; //N/m
+// At 5 bar: From steam tables
+t_s=151.8; //0C
+h_f=640.1; //kJ/kg
+h_fg=2107.4; //kJ/kg
+v_g=0.375; //m^3/kg
+v_g1=0.375*10^(-3);
+h1=h_f+h_fg;
+V=m*v_g;
+u1=h1-p1*v_g1;
+v_g2=V/m/x2; //m^3/kg
+
+// From steam table corresponding to 0.625 m^3/kg
+p2=2.9; //bar
+disp("Pressure at new state =")
+disp(p2)
+disp("bar")
+
+t_s=132.4; //0C
+disp("Temperature at new state =")
+disp(t_s)
+disp("°C")
+h_f2=556.5; //kJ/kg
+h_fg2=2166.6; //kJ/kg
+u2=(h_f2+x2*h_fg2)-p2*x2*v_g2*10^2;
+
+Q=u2-u1; //heat transferred at constant volume per kg
+
+disp("Total heat transfered,Q_total=")
+Q_total=m*Q;
+disp(Q_total)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.1/1.sce b/551/CH4/EX4.1/1.sce new file mode 100755 index 000000000..82b6ad3e1 --- /dev/null +++ b/551/CH4/EX4.1/1.sce @@ -0,0 +1,7 @@ +clc
+Q=-50; //kJ/kg
+W=-100; //kJ/kg
+dU=Q-W;
+disp("gain in internal energy = ")
+disp(dU)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.10/10.sce b/551/CH4/EX4.10/10.sce new file mode 100755 index 000000000..825365ffd --- /dev/null +++ b/551/CH4/EX4.10/10.sce @@ -0,0 +1,26 @@ +clc
+Q_lqm=168; //kJ
+W_lqm=64; //kJ
+dU_lm=Q_lqm - W_lqm;
+W_lnm=21; //kJ
+W_ml=-42; //kJ
+
+Q_lnm=dU_lm + W_lnm;
+disp("(i)Q_lnm=")
+disp(Q_lnm)
+disp("kJ")
+
+
+Q_ml=W_ml - dU_lm;
+disp("(ii)Q_ml = ")
+disp(Q_ml)
+disp("kJ")
+
+
+W_ln=21; //kJ
+dU_ln=84; //kJ
+Q_ln=dU_ln + W_ln;
+Q_nm=Q_lnm-Q_ln;
+disp("Q_nm = ")
+disp(Q_nm)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.11/11.sce b/551/CH4/EX4.11/11.sce new file mode 100755 index 000000000..9ba496bc0 --- /dev/null +++ b/551/CH4/EX4.11/11.sce @@ -0,0 +1,9 @@ +clc
+T1=55; //0C
+T2=95; //0C
+W=integrate('200', 'T', T1, T2);
+Q=integrate('160', 'T', T1, T2);
+dU=Q-W;
+disp("change in internal energy=")
+disp(dU/10^3)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.12/12.sce b/551/CH4/EX4.12/12.sce new file mode 100755 index 000000000..684761e69 --- /dev/null +++ b/551/CH4/EX4.12/12.sce @@ -0,0 +1,49 @@ +clc
+Q=-340; //kJ
+n=200; //cycles/min
+
+//For Process 1-2
+
+W_12=4340; //kJ/min
+Q_12=0;
+
+dE_12=Q_12-W_12;
+disp("dE_12 =")
+disp(dE_12)
+disp("kJ/min")
+
+//For process 2-3
+
+Q_23=42000; //kJ/min
+W_23=0;
+
+dE_23=Q_23-W_23;
+disp("dE_23 =")
+disp(dE_23)
+disp("kJ/min")
+
+//For process 3-4
+
+Q_34=-4200; //kJ/min
+dE_34=-73200; //kJ/min
+
+W_34=Q_34-dE_34;
+disp("W_34 =")
+disp(W_34)
+disp("kJ/min")
+
+//For process 4-1
+Q_41=Q*n-Q_12-Q_23-Q_34;
+disp("Q_41 =")
+disp(Q_41)
+disp("kJ/min")
+
+dE_41=0-dE_12-dE_23-dE_34;
+disp("dE_41 =")
+disp(dE_41)
+disp("kJ/min")
+
+W_41=Q_41-dE_41;
+disp("W_41 =")
+disp(W_41)
+disp("kJ/min")
\ No newline at end of file diff --git a/551/CH4/EX4.13/13.sce b/551/CH4/EX4.13/13.sce new file mode 100755 index 000000000..87156207b --- /dev/null +++ b/551/CH4/EX4.13/13.sce @@ -0,0 +1,11 @@ +clc
+P=1200; //kW
+Qin=3360; //kJ/kg
+Qout=2520; //kJ/kg
+F=6; //kW
+dQ=Qin - Qout;
+dW=P-F; //kJ/s
+m = dW/dQ;
+disp("Steam flow round the cycle")
+disp(m)
+disp("kg/s")
\ No newline at end of file diff --git a/551/CH4/EX4.14/14.sce b/551/CH4/EX4.14/14.sce new file mode 100755 index 000000000..c7ad70abd --- /dev/null +++ b/551/CH4/EX4.14/14.sce @@ -0,0 +1,16 @@ +clc
+dT=25; //0C
+Q=30; //kJ
+cv=1.2; //kJ/kg.0C
+m=2.5; //kg
+dU=m*cv*dT;
+
+
+disp("change in internal energy = ")
+disp(dU)
+disp("kJ")
+
+W=Q - dU;
+disp("Work done = ")
+disp(W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.15/15.sce b/551/CH4/EX4.15/15.sce new file mode 100755 index 000000000..f46b046b1 --- /dev/null +++ b/551/CH4/EX4.15/15.sce @@ -0,0 +1,31 @@ +clc
+Q=50; //kJ
+dV=0.14; //m^3
+p=1.2*10^5; //N/m^2
+m=90; //kg
+d=5.5; //m
+g=9.8; //m/s^2
+W_adb = -110; //kJ
+Wnet=m*g*d/1000; //kJ
+
+
+disp("(i)Change in internal energy")
+W=p*dV/1000 + Wnet; //kJ
+dE=Q-W;
+disp("dE=")
+disp(dE)
+disp("kJ")
+
+disp("(ii) Adiabatic process")
+Q=0;
+dE=-W_adb;
+disp("dE=")
+disp(dE)
+disp("kJ")
+
+disp("(iii)Change in internal energy")
+Q=50; //kJ
+dE=Q - [W_adb+W];
+disp("dE=")
+disp(dE)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.16/16.sce b/551/CH4/EX4.16/16.sce new file mode 100755 index 000000000..5a54bf7c9 --- /dev/null +++ b/551/CH4/EX4.16/16.sce @@ -0,0 +1,21 @@ +clc
+V1=0.15; //m^3
+V2=0.05; //m^3
+Q=-45; //kJ
+p1=(5/V1+1.5)*10^5; //N/m^2
+p2=(5/V2+1.5)*10^5; //N/m^2
+W=integrate('(5/V+1.5)*10^2', 'V', V1, V2);
+
+
+disp("(i)Change in internal energy = ")
+dU=Q-W;
+disp("dU=")
+disp(dU)
+disp("kJ")
+
+
+disp("(ii) Change in enthalpy")
+dH=(dU*10^3+(p2*V2-p1*V1))/10^3;
+disp("dH=")
+disp(dH)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.17/17.sce b/551/CH4/EX4.17/17.sce new file mode 100755 index 000000000..4b53e4a70 --- /dev/null +++ b/551/CH4/EX4.17/17.sce @@ -0,0 +1,27 @@ +clc
+V1=0.25; //m^3
+p1=500; //kPa
+p2=100; //kPa
+V2=V1*(p1/p2)^(1/1.25)
+n=1.25
+dU=3.64*(p2*V2 - p1*V1)
+
+
+disp("(i) If the expansion is quasi-static")
+W=(p1*V1-p2*V2)/(n-1);
+Q=dU+W
+disp("Heat transfered=")
+disp(Q)
+disp("kJ")
+
+
+disp("(ii) In another process")
+Q=32; //kJ
+W=Q-dU;
+disp("Work done=")
+disp(W)
+disp("kJ")
+
+
+disp("(iii)The difference")
+disp("(iii) The work in (ii) is not equal to ∫ p dV since the process is not quasi-static.")
\ No newline at end of file diff --git a/551/CH4/EX4.18/18.sce b/551/CH4/EX4.18/18.sce new file mode 100755 index 000000000..3f3709894 --- /dev/null +++ b/551/CH4/EX4.18/18.sce @@ -0,0 +1,33 @@ +clc
+v1=0.3; //m^3/kg
+T1=20; //0C
+v2=0.55; //m^3/kg
+T2=260; //0C
+p=1.6*10^5; //Pa
+
+disp("(i)Heat added per kg = ")
+Q=integrate('1.5 + 75/(T+45)', 'T', T1,T2);
+disp("Q=")
+disp(Q)
+disp("kJ/kg")
+
+
+disp("(ii)The work done per kg of fluid")
+W=p*(v2-v1)/1000; //kJ/kg
+disp("W=")
+disp(W)
+disp("kJ/kg")
+
+
+disp("(iii)Change in internal energy")
+dU=Q-W;
+disp("dU=")
+disp(dU)
+disp("kJ/kg")
+
+
+disp("(iv)Change in enthalpy")
+dH=Q;
+disp("dH=")
+disp(dH)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.19/19.sce b/551/CH4/EX4.19/19.sce new file mode 100755 index 000000000..3f14a2dcf --- /dev/null +++ b/551/CH4/EX4.19/19.sce @@ -0,0 +1,11 @@ +clc
+m=1; //kg
+du=-42000; //J
+cp=840; //J/kg.0C
+cv=600; //J/kg.0C
+dT=du/m/cv;
+Q=m*cp*dT;
+W=(Q-du)/10^3;
+disp("Work done=")
+disp(W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.2/2.sce b/551/CH4/EX4.2/2.sce new file mode 100755 index 000000000..49ac83698 --- /dev/null +++ b/551/CH4/EX4.2/2.sce @@ -0,0 +1,8 @@ +clc
+u1=450; //kJ/kg
+u2=220; //kJ/kg
+W=120; //kJ/kg
+Q=(u2-u1) + W;
+disp("Heat rejected by air =")
+disp(-Q)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.20/20.sce b/551/CH4/EX4.20/20.sce new file mode 100755 index 000000000..f6fe8e3d8 --- /dev/null +++ b/551/CH4/EX4.20/20.sce @@ -0,0 +1,25 @@ +clc
+p1=190; //kPa
+V1=0.035; //m^3
+p2=420; //kPa
+V2=0.07; //m^3
+dU=3.6*(p2*V2-p1*V1);
+// p=a+b*v
+// a+0.035*b=190
+// a+0.07*b=420
+// solving the two equations
+p=[1,0.035;1,0.07];
+q=[190;420];
+X=inv(p)*q;
+a=X(1,1);
+b=X(2,1);
+W=integrate('a+b*V', 'V', V1, V2);
+disp("Work done by the system = ")
+disp(W)
+disp("kJ")
+
+
+Q=dU+W;
+disp("Heat transfer into the system = ")
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.21/21.sce b/551/CH4/EX4.21/21.sce new file mode 100755 index 000000000..7704f51a5 --- /dev/null +++ b/551/CH4/EX4.21/21.sce @@ -0,0 +1,21 @@ +clc
+Qv=90; //kJ
+Qp=-95; //kJ
+W=-18; //kJ
+U_l=105; //kJ
+W_lm=0;
+Q_lm=90;
+U_m=U_l+90;
+dU_mn=Qp-W;
+U_n=U_m+dU_mn;
+dQ=Qv+Qp;
+dW=dQ;
+W_nl=dW-W;
+disp("W_nl(in kJ)=")
+disp(W_nl)
+disp("U_l in kJ =")
+disp(U_l)
+disp("U_m in kJ =")
+disp(U_m)
+disp("U_n in kJ")
+disp(U_n)
\ No newline at end of file diff --git a/551/CH4/EX4.23/23.sce b/551/CH4/EX4.23/23.sce new file mode 100755 index 000000000..2396a1171 --- /dev/null +++ b/551/CH4/EX4.23/23.sce @@ -0,0 +1,29 @@ +clc
+V1=0.2; //m^3
+p1=4*10^5; //N/m^2
+T1=403; //K
+p2=1.02*10^5; //N/m^2
+dH=72.5; //kJ
+Q_23=dH;
+cp=1; //kJ/kg
+cv=0.714; //kJ/kg
+y=1.4;
+V2=V1*(p1/p2)^(1/y);
+T2=T1*((p2/p1)^((y-1)/y));
+R=(cp-cv)*1000; //J/kg.K
+m=p1*V1/R/T1;
+T3=Q_23/(m*cp) +T2;
+V3=V2*T3/T2;
+W_12=(p1*V1 - p2*V2)/(y-1);
+W_23=p2*(V3-V2);
+W_123=W_12+W_23;
+disp("Total work done = ")
+disp(W_123)
+disp("J")
+
+
+disp("(ii) Index of expansion, n")
+p3=p2;
+n=(p1*V1-p3*V3)/W_123 + 1;
+disp("value of index = ")
+disp(n)
\ No newline at end of file diff --git a/551/CH4/EX4.25/25.sce b/551/CH4/EX4.25/25.sce new file mode 100755 index 000000000..278dce86c --- /dev/null +++ b/551/CH4/EX4.25/25.sce @@ -0,0 +1,20 @@ +clc
+d=0.15; //m
+T=303; //K
+p=3*10^5; //N/m^2
+l=0.085; //m
+Q=-4000; //J
+
+disp("(i) Workdone by the system")
+dv=%pi/4*d^2*l;
+W=p*dv;
+disp("W=")
+disp(W/10^3)
+disp("kJ")
+
+
+disp("(ii) Decrease in internal energy of the system")
+dU=(Q-W)/10^3;
+disp("Decrease in internal energy = ")
+disp(-dU)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.27/27.sce b/551/CH4/EX4.27/27.sce new file mode 100755 index 000000000..0ca9be4c4 --- /dev/null +++ b/551/CH4/EX4.27/27.sce @@ -0,0 +1,37 @@ +clc
+y=1.4
+R=294.2; //J/kg.0C
+p1=1*10^5; //N/m^2
+T1=353; //K
+V1=0.45; //m^3
+V2=0.13; //m^3
+p2=5*10^5; //N/m^2
+cv=R/(y-1);
+
+disp("(i) The mass of gas")
+m=p1*V1/R/T1;
+disp("m=")
+disp(m)
+disp("kg")
+
+
+disp("(ii) The value of index ‘n’ for compression")
+n=log(p2/p1)/log(V1/V2);
+disp("n=")
+disp(n)
+
+
+disp("(iii) The increase in internal energy of the gas")
+T2=T1*(V1/V2)^(n-1);
+dU=m*cv*(T2-T1)/10^3;
+disp("dU=")
+disp(dU)
+disp("kJ")
+
+
+disp("(iv) The heat received or rejected by the gas during compression.")
+W=m*R*(T1-T2)/(n-1)/10^3;
+Q=dU+W;
+disp("Q=")
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.28/28.sce b/551/CH4/EX4.28/28.sce new file mode 100755 index 000000000..9e9f9002c --- /dev/null +++ b/551/CH4/EX4.28/28.sce @@ -0,0 +1,30 @@ +clc
+p1=1.02*10^5; //Pa
+T1=295; //K
+V1=0.015; //m^3
+p2=6.8*10^5; //Pa
+y=1.4;
+
+
+disp("(i) Final temperature")
+T2=T1*(p2/p1)^((y-1)/y);
+t2=T2-273;
+disp("t2=")
+disp(t2)
+disp("°C")
+
+
+disp("(ii) Final volume :")
+V2=V1*(p1/p2)^(1/y);
+disp("V2=")
+disp(V2)
+disp("m^3")
+
+
+disp("(iii)Work done")
+R=287;
+m=p1*V1/R/T1;
+W=m*R*(T1-T2)/(y-1)/10^3;
+disp("W=")
+disp(W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.29/29.sce b/551/CH4/EX4.29/29.sce new file mode 100755 index 000000000..c94f4d613 --- /dev/null +++ b/551/CH4/EX4.29/29.sce @@ -0,0 +1,24 @@ +clc
+m=0.44; //kg
+T1=453; //K
+ratio=3; //ratio=V2/V1
+T2=288; //K
+W_12=52.5; //kJ
+y=log(T2/T1)/ log(1/ratio) + 1;
+R=W_12*(y-1)/m/(T1-T2);
+// We have got two equations
+// cp-cv=R
+// cp-y*cv=0
+M=[1,-1;1,-y];
+N=[R;0];
+X=inv(M)*N;
+cp=X(1,1);
+cv=X(2,1);
+disp("cp=")
+disp(cp)
+disp("kJ/kg.K")
+
+
+disp("cv=")
+disp(cv)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH4/EX4.3/3.sce b/551/CH4/EX4.3/3.sce new file mode 100755 index 000000000..b88baa3a9 --- /dev/null +++ b/551/CH4/EX4.3/3.sce @@ -0,0 +1,11 @@ +clc
+m=0.3; //kg
+cv=0.75; //kJ/kg.K
+T1=313; //K
+T2=433; //K
+W=-30; //kJ
+dU=m*cv*(T2-T1);
+Q=dU + W;
+disp("Heat rejected during the process=")
+disp(-Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.30/30.sce b/551/CH4/EX4.30/30.sce new file mode 100755 index 000000000..1499b08a1 --- /dev/null +++ b/551/CH4/EX4.30/30.sce @@ -0,0 +1,18 @@ +clc
+n=1.3;
+m=1; //kg
+p1=1.1; //bar
+T1=300; //K
+p2=6.6; //bar
+R0=8314;
+M=30;
+cp=1.75; //kJ/kg.K
+R=R0/M/1000; //kJ/kg.K
+cv=cp - R;
+y=cp/cv;
+T2=T1 *(p2/p1)^((n-1)/n);
+W=R*(T1-T2)/(n-1);
+Q=((y-n)/(y-1))*W;
+disp("Heat supplied = ")
+disp(Q)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.31/31.sce b/551/CH4/EX4.31/31.sce new file mode 100755 index 000000000..7ecaad192 --- /dev/null +++ b/551/CH4/EX4.31/31.sce @@ -0,0 +1,42 @@ +clc
+cp=14.3; //kJ/kg.K
+cv=10.2; //kJ/kg.K
+V1=0.1; //m^3
+T1=300; //K
+p1=1; //bar
+p2=8; //bar
+y=cp/cv;
+R=cp-cv;
+V2=V1*(p1/p2)^(1/y);
+V3=V2;
+T2=T1*(p2/p1)^((y-1)/y);
+p3=p1*V1/V3;
+T3=300; //K
+
+
+disp("(i) Pressure at the end of constant volume cooling = ")
+disp(p3)
+disp("bar")
+
+
+disp("(ii) Change in internal energy during constant volume process")
+m=p1*V1/R/T1*10^2; //kg
+
+dU_23=m*cv*(T3-T2);
+disp("dU_23 = ")
+disp(dU_23)
+disp("kJ")
+
+
+disp("(iii) Net work done and heat transferred during the cycle")
+W_12=m*R*(T1-T2)/(y-1);
+W_23=0;
+W_31=p3*V3*log(V1/V3)*10^2; //kJ
+disp("Net work done=")
+Wnet=W_12+W_23+W_31;
+disp(Wnet)
+disp("kJ")
+Qnet=Wnet;
+disp("Heat transferred during the complete cycle = ")
+disp(Qnet)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.32/32.sce b/551/CH4/EX4.32/32.sce new file mode 100755 index 000000000..b97de6dd6 --- /dev/null +++ b/551/CH4/EX4.32/32.sce @@ -0,0 +1,24 @@ +clc
+V1=0.15; //m^3
+p1=15; //bar
+T1=550; //K
+T2=T1;
+r=4; //r=V2/V1
+V2=r*V1;
+T3=290; //K
+p2=p1*V1/V2;
+W_12=p1*V1*log(V2/V1)*10^2; //kJ
+V3=V2;
+p3=p2*T3/T2;
+W_23=0;
+n=log(p1/p3)/log(V3/V1);
+W_31=(p3*V3-p1*V1)/(n-1)*10^2; //kJ
+
+disp("net work done = ")
+Wnet=W_12+W_23+W_31
+disp("kJ")
+
+Qnet=Wnet;
+disp("Heat transferred during the cycle = ")
+disp(Qnet)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.33/33.sce b/551/CH4/EX4.33/33.sce new file mode 100755 index 000000000..7ad63df02 --- /dev/null +++ b/551/CH4/EX4.33/33.sce @@ -0,0 +1,71 @@ +clc
+m=1; //kg
+p1=5; //bar
+V1=0.02; //m^3
+V2=0.08; //m^3
+p2=1.5; //bar
+
+function p=f(V)
+ p=a+b*V;
+endfunction
+
+// 5=a+0.02*b
+// 1.5=a+0.08*b
+// Solving above two equations
+
+A=[1,0.02;1,0.08];
+B=[5;1.5];
+X=inv(A)*B;
+a=X(1,1);
+b=X(2,1);
+
+disp("(i) p-V diagram")
+
+V=0.02:0.001:0.08;
+p=a+b*V;
+plot(V,p,'b')
+
+V=[0.0667 0.08];
+p=[1.5 1.5];
+plot(V,p,'g')
+
+V=0.02:0.001:0.0667;
+function p=fa(V)
+ p=0.1/V;
+endfunction
+
+plot(V,fa,'r')
+
+V=[0.0667 0.0667];
+p=[1.5 0];
+plot(V,p,'--')
+
+xtitle("p-V diagram", "V(m^3)", "p(bar)");
+legend("p=a+b*V","p=constant","pv=constant")
+
+
+disp("(ii) Work done and heat transfer")
+
+W_12=integrate('(a+b*V)*10^2','V',V1,V2);
+disp("Work done by the system =")
+disp(W_12)
+disp("kJ")
+
+p3=p2;
+V3=p1*V1/p3;
+W_23=p2*(V3-V2)*10^2; //kJ
+
+W_31=p3*V3*log(V1/V3)*10^2; //kJ
+disp("Work done on the system =")
+disp(W_31)
+disp("kJ")
+
+W_net=W_12+W_23+W_31;
+disp("Net work done =")
+disp(W_net)
+disp("kJ")
+
+Q_net=W_net;
+disp("Heat transferred during the complete cycle =")
+disp(Q_net)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.34/34.sce b/551/CH4/EX4.34/34.sce new file mode 100755 index 000000000..a60573e82 --- /dev/null +++ b/551/CH4/EX4.34/34.sce @@ -0,0 +1,24 @@ +clc
+cv=0.71; //kJ/kg.K
+R=0.287; //kJ/kg.K
+d=8; //cm
+l=3.5; //cm
+S=150; //N/cm
+p1=30; //N/cm
+V1=45; //cm^3
+T1=293; //K
+cv=0.71; //kJ/kg.K
+R=0.287; //kJ/kg.K
+A=%pi/4*d^2;
+C=p1-S/A^2*V1;
+dV=l*A;
+V2=V1+dV;
+p2=S/A^2*V2 + C;
+W=integrate('A^2/S*p/100', 'p', p1, p2);
+T2=p2*V2*T1/p1/V1;
+m=p1*V1/R/T1/10^5; //kg
+dU=m*cv*(T2-T1);
+Q_12=dU + W*10^(-3);
+disp("Amount of heat added to the system = ")
+disp(Q_12)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.35/35.sce b/551/CH4/EX4.35/35.sce new file mode 100755 index 000000000..5f8edaff2 --- /dev/null +++ b/551/CH4/EX4.35/35.sce @@ -0,0 +1,36 @@ +clc
+r=10; //kg/min
+p1=1.5*10^5; //N/m^2
+rho1=26; //kg/m^3
+C1=110; //m/s
+u1=910; //kJ/kg
+p2=5.5*10^5; //N/m^2
+rho2=5.5; //kg/m^3
+C2=190; //m/s
+u2=710; //kJ/kg
+Q=55; //kJ/s
+h=55; //m
+g=9.81; //m/s^2
+v2=1/rho2;
+v1=1/rho1;
+
+disp("(i) Change in enthalpy")
+dh=u2-u1+ (p2*v2-p1*v1)/10^3;
+disp(dh)
+disp("kJ/kg")
+
+disp("(ii) Work done during the process (W).")
+
+Q=330; //kJ/kg
+KE=(C2^2-C1^2)/2/10^3; //kJ
+PE=g*h/10^3; //kJ
+W=-Q-KE-PE-dh;
+disp("Work done = ")
+disp(W)
+disp("kJ")
+
+
+disp("Work done per second = ")
+P=W*10/60;
+disp(P)
+disp("kW")
\ No newline at end of file diff --git a/551/CH4/EX4.36/36.sce b/551/CH4/EX4.36/36.sce new file mode 100755 index 000000000..74c5a1352 --- /dev/null +++ b/551/CH4/EX4.36/36.sce @@ -0,0 +1,22 @@ +clc
+m=15; //kg/s
+v=0.45; //m^3/kg
+P=12000; //kW
+W=P/m; //kJ/kg
+h1=1260; //kJ/kg
+h2=400; //kJ/kg
+C1=50; //m/s
+C2=110; //m/s
+
+disp("(i) Heat rejected = ")
+Q=h2-h1+(C2^2-C1^2)/2/10^3 +W;
+Qnet=m*Q;
+disp("Qnet=")
+disp(-Qnet)
+disp("kW")
+
+disp("(ii) Inlet area")
+A=v*m/C1;
+disp("A=")
+disp(A)
+disp("m^2")
\ No newline at end of file diff --git a/551/CH4/EX4.37/37.sce b/551/CH4/EX4.37/37.sce new file mode 100755 index 000000000..79e8ef68b --- /dev/null +++ b/551/CH4/EX4.37/37.sce @@ -0,0 +1,30 @@ +clc
+m=0.5; //kg/s
+C1=6; //m/s
+C2=5; //m/s
+p1=1; //bar
+p2=7; //bar
+v1=0.85; //m^3/kg
+v2=0.16; //m^3/kg
+du=90; //kJ/kg
+Q=-120; //kJ/kg
+
+
+disp("(i) Power required to drive the compressor")
+W=-du+(C1^2-C2^2)/2/1000 + (p1*v1 - p2*v2)*10^2 + Q;
+Power=m*W;
+disp("Power=")
+disp(-Power)
+disp("kW")
+
+
+disp("(ii) Inlet and outlet pipe cross-sectional areas")
+A1=m*v1/C1;
+A2=m*v2/C2;
+disp("Inlet crosssectional area = ")
+disp(A1)
+disp("m^2")
+
+disp("Outlet crossectional area=")
+disp(A2)
+disp("m^2")
\ No newline at end of file diff --git a/551/CH4/EX4.38/38.sce b/551/CH4/EX4.38/38.sce new file mode 100755 index 000000000..0d979f9e2 --- /dev/null +++ b/551/CH4/EX4.38/38.sce @@ -0,0 +1,12 @@ +clc
+h1=800; //kJ/kg
+C1=5; //m/s
+h2=2520; //kJ/kg
+C2=50; //m/s
+dZ=4; //m
+g=9.81; //m/s^2
+Q=2180; //kJ/kg
+W=h1-h2+(C1^2 - C2^2)/2/1000 +dZ*g/1000+Q;
+disp("Power developed = ")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH4/EX4.39/39.sce b/551/CH4/EX4.39/39.sce new file mode 100755 index 000000000..e49581e80 --- /dev/null +++ b/551/CH4/EX4.39/39.sce @@ -0,0 +1,14 @@ +clc
+g=9.8; //m/s^2
+m=4500/3600; //kg/s
+C1=2800/60; //m/s
+Z1=5.5; //m
+h1=2800; //kJ/g
+C2=5600/60; //m/s
+Z2=1.5; //m
+h2=2300; //kJ/kg
+Q=-16000/3600; //kJ/s
+W=Q-m*[(h1-h2) + (C2^2 - C1^2)/2/1000 + (Z2-Z1)*g/1000];
+disp("Power output of the turbine = ")
+disp(-W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH4/EX4.4/4.sce b/551/CH4/EX4.4/4.sce new file mode 100755 index 000000000..21efac61b --- /dev/null +++ b/551/CH4/EX4.4/4.sce @@ -0,0 +1,11 @@ +clc
+p1=105; //kPa
+V1=0.4; //m^3
+p2=p1;
+V2=0.20; //m^3
+Q=-42.5; //kJ
+W=p1*(V2-V1);
+dU=Q-W;
+disp("change in internal energy = ")
+disp(dU)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.40/40.sce b/551/CH4/EX4.40/40.sce new file mode 100755 index 000000000..4690e366e --- /dev/null +++ b/551/CH4/EX4.40/40.sce @@ -0,0 +1,11 @@ +clc
+p1=6.87; //bar
+C1=50; //m/s
+p2=1.37; //bar
+C2=500; //m/s
+disp("From steam table corresponding to p1")
+h1=2850; //kJ/kg
+h2=h1 - (C2^2-C1^2)/2/1000;
+disp("Final enthalpy of steam = ")
+disp(h2)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.41/41.sce b/551/CH4/EX4.41/41.sce new file mode 100755 index 000000000..48163c0bb --- /dev/null +++ b/551/CH4/EX4.41/41.sce @@ -0,0 +1,15 @@ +clc
+m=220/60; //kg/s
+C1=320; //m/s
+p1=6*10^5; //N/m^2
+u1=2000*10^3; //J/kg
+v1=0.36; //m^3/kg
+C2=140; //m/s
+p2=1.2*10^5; //N/m^2
+u2=1400*10^3; //J/kg
+v2=1.3; //m^3/kg
+Q=100*10^3; //J/s
+W=(m*[(u1-u2)+ (p1*v1 - p2*v2) + (C1^2-C2^2)/2] -Q)/10^6;
+disp("power capacity of the system = ")
+disp(W)
+disp("MW")
\ No newline at end of file diff --git a/551/CH4/EX4.42/42.sce b/551/CH4/EX4.42/42.sce new file mode 100755 index 000000000..5feee9359 --- /dev/null +++ b/551/CH4/EX4.42/42.sce @@ -0,0 +1,13 @@ +clc
+p1=7.5*10^5; //N/m^2
+C1=140; //m/s
+h1=950*10^3; //J/kg
+p2=2*10^5; //N/m^2
+C2=280; //m/s
+h2=650*10^3; //J/kg
+m=5; //kg/s
+W=(h1-h2)+(C1^2-C2^2)/2
+Power=m*W/1000;
+disp("Power capacity of turbine = ")
+disp(Power)
+disp("kW")
\ No newline at end of file diff --git a/551/CH4/EX4.43/43.sce b/551/CH4/EX4.43/43.sce new file mode 100755 index 000000000..acba2a3e9 --- /dev/null +++ b/551/CH4/EX4.43/43.sce @@ -0,0 +1,22 @@ +clc
+C1=12; //m/s
+p1=1*10^5; //N/m^2
+v1=0.5; //m^3/kg
+C2=90; //m/s
+p2=8*10^5; //N/m^2
+v2=0.14; //m^3/kg
+dh=150; //kJ/kg
+Q=-11.67; //kJ/s
+m=0.2; //kg/s
+
+disp("(i) Motor power required to drive the compressor")
+W=m*[-dh + (C1^2-C2^2)/2/1000] +Q;
+disp("Power=")
+disp(-W)
+disp("kW")
+
+
+disp("(ii)Ratio of inlet to outlet pipi diameter")
+ratio=sqrt(C2/C1*v1/v2);
+disp("ratio=")
+disp(ratio)
\ No newline at end of file diff --git a/551/CH4/EX4.44/44.sce b/551/CH4/EX4.44/44.sce new file mode 100755 index 000000000..ea1304d75 --- /dev/null +++ b/551/CH4/EX4.44/44.sce @@ -0,0 +1,9 @@ +clc
+W=-175; //kJ/kg
+dh=70; //kJ/kg
+Q_water=-92; //kJ/kg
+Q=dh+W;
+Q_atm=Q-Q_water;
+disp("Heat transferred to the atmosphere = ")
+disp(-Q_atm)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.45/45.sce b/551/CH4/EX4.45/45.sce new file mode 100755 index 000000000..24c2bd6e7 --- /dev/null +++ b/551/CH4/EX4.45/45.sce @@ -0,0 +1,27 @@ +clc
+h1=2800*10^3; //J/kg
+C1=50; //m/s
+A1=900*10^(-4); //m^2
+v1=0.187; //m^3/kg
+h2=2600*10^3; //J/kg
+v2=0.498; //m^3/kJ
+disp("(i) Velocity at exit of the nozzle")
+C2=sqrt(2*[(h1-h2) + C1^2/2]);
+
+disp("C2=")
+disp(C2)
+disp("m/s")
+
+
+disp("(ii) Mass flow rate")
+m=A1*C1/v1;
+disp("m=")
+disp(m)
+disp("kg/s")
+
+
+disp("(iii) Area at the exit")
+A2=m*v2/C2*10^4;
+disp("A2=")
+disp(A2)
+disp("cm^2")
\ No newline at end of file diff --git a/551/CH4/EX4.46/46.sce b/551/CH4/EX4.46/46.sce new file mode 100755 index 000000000..ed10ee594 --- /dev/null +++ b/551/CH4/EX4.46/46.sce @@ -0,0 +1,10 @@ +clc
+h1=240; //kJ/kg
+h2=192; //kJ/kg
+dZ=20; //m
+g=9.81; //m/s^2
+Q=(h2-h1)+dZ*g/1000;
+
+disp("heat transfer = ")
+disp(-Q)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.47/47.sce b/551/CH4/EX4.47/47.sce new file mode 100755 index 000000000..6e419a580 --- /dev/null +++ b/551/CH4/EX4.47/47.sce @@ -0,0 +1,10 @@ +clc
+p1=2; //bar
+C1=300; //m/s
+Q=0;
+h1=915*10^3; //J/kg
+h2=800*10^3; //J/kg
+C2=sqrt(2*[h1-h2 + C1^2/2]);
+disp("Relative velocity of gas leaving the pipe=")
+disp(C2)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH4/EX4.48/48.sce b/551/CH4/EX4.48/48.sce new file mode 100755 index 000000000..515ae81b2 --- /dev/null +++ b/551/CH4/EX4.48/48.sce @@ -0,0 +1,17 @@ +clc
+mw=50; //kg/s
+p1=10^5; //N/m^2
+p2=4.2*10^5; //N/m^2
+h=10.7; //m
+d1=0.2; //m
+d2=0.1; //m
+v1=1/1000;
+v2=1/1000;
+g=9.81; //m/s^2
+
+C1=mw*4/%pi/d1^2*v1;
+C2=mw*4/%pi/d2^2*v2;
+W=mw*[(p1*v1-p2*v2) + (g*(0-h))+(C1^2-C2^2)/2]/10^3;
+disp("Capacity of electric motor")
+disp(-W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH4/EX4.49/49.sce b/551/CH4/EX4.49/49.sce new file mode 100755 index 000000000..240864beb --- /dev/null +++ b/551/CH4/EX4.49/49.sce @@ -0,0 +1,16 @@ +clc
+Ca=250; //m/s
+t=-14; //0C
+ha=250; //kJ/kg
+hg=900; //kJ/kg
+ratio=0.0180;
+Ef=45*10^3; //kJ/kg
+Q=-21; //kJ/kg
+ma=1; //kg
+mg=1.018; //kg
+mf=0.018; //kg
+Eg=0.06*mf/mg*Ef;
+Cg=sqrt(2000*([ma*(ha+Ca^2/2/1000) + mf*Ef + Q]/mg -hg-Eg));
+disp("velocity of exhaust gas jet = ")
+disp(Cg)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH4/EX4.50/50.sce b/551/CH4/EX4.50/50.sce new file mode 100755 index 000000000..a8f701e3a --- /dev/null +++ b/551/CH4/EX4.50/50.sce @@ -0,0 +1,31 @@ +clc
+t1=20; //0C
+C1=40; //m/s
+t2=820; //0C
+C2=40; //m/s
+t3=620; //0C
+C3=55; //m/s
+t4=510; //0C
+m=2.5; //kg/s
+cp=1.005; //kJ/kg.0C
+
+
+disp("(i) Heat exchanger")
+Q_12=m*cp*(t2-t1);
+disp("rate of heat transfer=")
+disp(Q_12)
+disp("kJ/s")
+
+
+disp("(ii) Turbine")
+W_23=m*[(cp*(t2-t3))+(C2^2-C3^2)/2/1000];
+disp("Power output of turbine=")
+disp(W_23)
+disp("kW")
+
+
+disp("(iii) Nozzle")
+C4=sqrt(2*1000*(cp*(t3-t4)+C3^2/2/1000));
+disp("Velocity at exit from the nozzle= ")
+disp(C4)
+disp("m/s")
\ No newline at end of file diff --git a/551/CH4/EX4.51/51.sce b/551/CH4/EX4.51/51.sce new file mode 100755 index 000000000..816c8187b --- /dev/null +++ b/551/CH4/EX4.51/51.sce @@ -0,0 +1,28 @@ +clc
+V=0.028; //m^3
+p1=80; //bar
+t=350; //0C
+p2=50; //bar
+v1=0.02995; //m^3/kg
+h1=2987.3; //kJ/kg
+v2=0.02995; //m^3/kg
+vg2=0.0394; //m^3/kg
+uf2=1149; //kJ/kg
+ug2=2597; //kJ/kg
+
+m=V/v1;
+u1=h1 - (p1*v1*10^2); //kJ/kg
+
+
+disp("(i) State of steam after cooling")
+x2=v2/vg2;
+disp("dryness fraction = ")
+disp(x2)
+
+
+disp("(ii) Heat rejected by the steam")
+u2=(1-x2)*uf2 + x2*ug2;
+Q=m*(u2-u1);
+disp("Heat rejected = ")
+disp(-Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.52/52.sce b/551/CH4/EX4.52/52.sce new file mode 100755 index 000000000..18da48a90 --- /dev/null +++ b/551/CH4/EX4.52/52.sce @@ -0,0 +1,22 @@ +clc
+m=0.08; //kg
+p=2*10^5; //Pa
+V=0.10528; //m^3
+h1=2706.3; //kJ/kg
+h2=3071.8; //kJ/kg
+v1=0.885; //m^3/kg
+v2=V/m; //m^3/kg
+
+
+disp("(i) Heat supplied")
+Q=m*(h2-h1);
+disp("Q=")
+disp(Q)
+disp("kJ")
+
+disp("(ii) Work done")
+W=p*(v2-v1);
+W_total=m*W/10^3;
+disp("Total work done = ")
+disp(W_total)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.53/53.sce b/551/CH4/EX4.53/53.sce new file mode 100755 index 000000000..ab3be111f --- /dev/null +++ b/551/CH4/EX4.53/53.sce @@ -0,0 +1,46 @@ +clc
+m=1; //kg
+p=8; //bar
+s1=6.55; //kJ/kg.K
+T=200; //0C
+s_f1=2.0457; //kJ/kg.K
+s_fg1=4.6139; //kJ/kg.K
+h_f1=720.9; //kJ/kg
+h_fg1=2046.5; //kJ/kg
+h2=2839.3; //kJ/kg
+
+x1=(s1-s_f1)/s_fg1;
+h1=h_f1+x1*h_fg1;
+Q=h2-h1;
+disp("Heat supplied=")
+disp(Q)
+disp("kJ/kg")
+
+// For T-s diagram
+
+s=0:0.01:10;
+T=(-(s-5)^2+298);
+plot(s,T)
+
+T=[295.44 295.44];
+s=[6.6 3.45];
+plot(s,T,'g')
+
+s=[6.6 7];
+T=[295.44 300];
+plot(s,T,'g')
+
+s=[6.55 6.55];
+T=[270 295.44];
+plot(s,T,'r')
+
+s=[6.6 6.6];
+T=[270 295.44];
+plot(s,T,'--r')
+
+s=[6.66 6.66];
+T=[270 295.44];
+plot(s,T,'r')
+
+xtitle("T-s diagram", "s(kJ/kg K)", "T(K)")
+//The area in red represents the heat flow and it goes upto x-axis
\ No newline at end of file diff --git a/551/CH4/EX4.54/54.sce b/551/CH4/EX4.54/54.sce new file mode 100755 index 000000000..d22eac08a --- /dev/null +++ b/551/CH4/EX4.54/54.sce @@ -0,0 +1,39 @@ +clc
+p1=7*10^5; //Pa
+p2=1.5*10^5; //Pa
+Q=420; //kJ/kg
+uf=696; //kJ/kg
+x=0.95;
+ug=2573; //kJ/kg
+u_f2=2580; //kJ/kg
+u_g2=2856; //kJ/kg
+x2=15/50;
+h_f1=697.1; //kJ/kg
+h_fg1=2064.9; //kJ.kg
+h_f2=2772.6; //kJ/kg
+h_g2=2872.9; //kJ/kg
+
+
+disp("(i) Change of internal energy")
+u1=(1-x)*uf + x*ug;
+u2=2602.8; //kJ/kg
+du=u2-u1;
+disp("du=")
+disp(du)
+disp("kJ/kg")
+
+
+disp("(ii) Change in enthalpy")
+h1=h_f1+x*h_fg1;
+h2=h_f2+x2*(h_g2-h_f2);
+dh=h2-h1;
+disp("dh=")
+disp(dh)
+disp("kJ/kg")
+
+
+disp("(iii) Work done = ")
+W=Q-du;
+disp("W=")
+disp(W)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.55/55.sce b/551/CH4/EX4.55/55.sce new file mode 100755 index 000000000..a6e182780 --- /dev/null +++ b/551/CH4/EX4.55/55.sce @@ -0,0 +1,21 @@ +clc
+p1=5.5*10^5; //Pa
+x1=1;
+p2=0.75*10^5; //Pa
+v1=0.3427; //m^3/kg
+v2=p1*v1/p2;
+// Since v2 > vg (at 0.75 bar), therefore, the steam is superheated at state 2.
+u2=2567.25; //kJ/kg
+u1=2565; //kJ/kg
+du=u2-u1; //kJ/kg
+C=p1*v1;
+
+disp("Work done = ")
+W=integrate('C/v', 'v', v1,v2)
+disp("N-m/kg")
+
+
+disp("Heat supplied = ")
+Q=du+W/10^3;
+disp(Q)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.56/56.sce b/551/CH4/EX4.56/56.sce new file mode 100755 index 000000000..0e257fd03 --- /dev/null +++ b/551/CH4/EX4.56/56.sce @@ -0,0 +1,21 @@ +p1=100; //bar
+p2=10; //bar
+s1=5.619; //kJ/kg.K
+T=584; //K
+s2=7.163; //kJ/kg.K
+u1=2545; //kJ/kg
+u2=2811.8; //kJ/kg
+
+
+disp("(i)Heat supplied ")
+Q=T*(s2-s1);
+disp("Q=")
+disp(Q)
+disp("kJ/kg")
+
+
+disp("(ii) Work done")
+W=Q-(u2-u1);
+disp("W=")
+disp(W)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.57/57.sce b/551/CH4/EX4.57/57.sce new file mode 100755 index 000000000..2b673337b --- /dev/null +++ b/551/CH4/EX4.57/57.sce @@ -0,0 +1,13 @@ +clc
+m=1; //kg
+p1=120*10^5; //N/m^2
+t1=400; //0C
+p2=38; //bar
+h1=3051.3; //kJ/kg
+v1=0.02108; //m^3/kg
+u1=h1-p1*v1/10^3; //kJ/kg
+u2=2602; //kJ/kg
+disp("WOrk done = ")
+W=u1-u2;
+disp(W)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.58/58.sce b/551/CH4/EX4.58/58.sce new file mode 100755 index 000000000..15bb06c02 --- /dev/null +++ b/551/CH4/EX4.58/58.sce @@ -0,0 +1,32 @@ +clc
+p1=7*10^5; //N/m^2
+x1=0.98;
+p2=0.34*10^5; //N/m^2
+vg=0.273; //m^3/kg
+n=1.1;
+v_g2=4.65; //m^3/kg
+u_f1=696; //kJ/kg
+u_g1=2573; //kJ/kg
+u_f2=302; //kJ/kg
+u_g2=2472; //kJ/kg
+
+
+v1=x1*vg;
+v2=v1*(p1/p2)^(1/n);
+x2=v2/v_g2;
+
+
+disp("(i) Work done by the steam during the process")
+W=(p1*v1-p2*v2)/(n-1)/10^3; //kJ/kg
+disp("W=")
+disp(W)
+disp("kJ/kg")
+
+
+disp("(ii) Heat transferred")
+u1=(1-x1)*u_f1+x1*u_g1;
+u2=(1-x2)*u_f2+x2*u_g2;
+Q=u2-u1 + W;
+disp("Q=")
+disp(Q)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.59/59.sce b/551/CH4/EX4.59/59.sce new file mode 100755 index 000000000..2d3adc890 --- /dev/null +++ b/551/CH4/EX4.59/59.sce @@ -0,0 +1,21 @@ +clc
+p1=15; //bar
+t1=350; //0C
+C1=60; //m/s
+p2=1.2; //bar
+C2=180; //m/s
+s1=7.102; //kJ/kg
+s_f2=1.3609; //kJ/kg
+s_g2=7.2884; //kJ/kg
+h_f2=439.4; //kJ/kg
+h_fg2=2241.1; //kJ/kg
+h1=3147.5; //kJ/kg
+
+
+x2=(s1 - s_f2)/(s_g2-s_f2);
+h2=h_f2+x2*h_fg2;
+
+W=(h1-h2) + (C1^2 - C2^2)/2/1000;
+disp("Work done = ")
+disp(W)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.6/25.sce b/551/CH4/EX4.6/25.sce new file mode 100755 index 000000000..3de31da00 --- /dev/null +++ b/551/CH4/EX4.6/25.sce @@ -0,0 +1,15 @@ +clc
+p=1.1; //bar
+x=0.95;
+c_pw=4.18;
+m1=90; //kg
+m2=5.25; //kg
+T1=25; //0C
+T2=40; //0C
+m=m1+m2;
+h_f=428.8; //kJ/kg
+h_fg= 2250.8; //kJ/kg
+m_s= [m*c_pw*(T2-T1)]/[(h_f + x*h_fg) - c_pw*T2];
+disp("Mass of steam condensed=")
+disp(m_s)
+disp("kg")
\ No newline at end of file diff --git a/551/CH4/EX4.60/60.sce b/551/CH4/EX4.60/60.sce new file mode 100755 index 000000000..430146318 --- /dev/null +++ b/551/CH4/EX4.60/60.sce @@ -0,0 +1,13 @@ +clc
+p1=10; //bar
+t1=200; //0C
+C1=60; //m/s^2
+c2=650; //m/s
+p2=1.5; //bar
+h1=2827.9; //kJ/kg
+h_f2=467.1; //kJ/kg
+h2=2618.45; //kJ/kg
+h_g2=2693.4; //kJ/kg
+x2=(h2-h_f2)/(h_g2-h_f2);
+disp("quality of steam leaving the nozzle=")
+disp(x2)
\ No newline at end of file diff --git a/551/CH4/EX4.61/61.sce b/551/CH4/EX4.61/61.sce new file mode 100755 index 000000000..e201c6b9b --- /dev/null +++ b/551/CH4/EX4.61/61.sce @@ -0,0 +1,8 @@ +clc
+h1=2776.4; //kJ/kg
+h2=h1;
+h_f1=884.6; //kJ/kg
+h_fg1=1910.3; //kJ/kg
+x1=(h1-h_f1)/h_fg1;
+disp("Initial dryness fraction = ")
+disp(x1)
\ No newline at end of file diff --git a/551/CH4/EX4.62/62.sce b/551/CH4/EX4.62/62.sce new file mode 100755 index 000000000..0b979f644 --- /dev/null +++ b/551/CH4/EX4.62/62.sce @@ -0,0 +1,9 @@ +p1=10; //bar
+x1=0.9; //bar
+p2=2; //bar
+
+
+// Using Mollier chart, we get
+x2=0.94;
+disp("x2 =")
+disp(x2)
\ No newline at end of file diff --git a/551/CH4/EX4.63/63.sce b/551/CH4/EX4.63/63.sce new file mode 100755 index 000000000..c92ae57b4 --- /dev/null +++ b/551/CH4/EX4.63/63.sce @@ -0,0 +1,74 @@ +clc
+
+disp("(a)From steam tables")
+
+p1=15*10^5; //Pa
+p2=7.5*10^5; //Pa
+h_f1=844.7; //kJ/kg
+ts1=198.3; //0C
+s_f1=2.3145; //kJ/kg.K
+s_g1=6.4406; //kJ/kg.K
+v_g1=0.132; //m^3/kg
+h_fg1=1945.2; //kJ/kg
+x1=0.95;
+h_f2=709.3; //kJ/kg
+h_fg2=2055.55; //kJ/kg
+s_f2=2.0195; //kJ/kg
+s_g2=6.6816; //kJ/kg.K
+v_g2=0.255; //m^3/kg
+x2=0.9;
+x3=1;
+s_f3=0.521; //kJ/kg K
+s_g3=8.330; //kJ/kg K
+
+h2=h_f2+x2*h_fg2;
+h1=h_f1 + x1*h_fg1;
+s1=s_f1 + x1*(s_g1-s_f1);
+s2=s1;
+ds_12=s2-s1;
+
+s3=s_f3+x3*(s_g3-s_f3);
+ds_23=s3-s2;
+
+ds=ds_12+ds_23;
+disp("(i) Change in entropy =")
+disp(ds)
+disp("kJ/kg K")
+
+h3=h2;
+
+disp("(ii) Change in enthalpy")
+dh=h2-h1;
+disp(dh)
+disp("kJ/kg")
+
+
+disp("(iii) Change in internal energy")
+u1=h1-p1*x1*v_g1/10^3;
+u2=h2-p2*x2*v_g2/10^3;
+du=u2-u1;
+disp("du=")
+disp(du)
+disp("kJ/kg")
+
+
+// Only the expansion of steam from point 1 to 2 (i.e., isentropic expansion) is reversible because of unresisted flow whereas the expansion from point 2 to point 3 (i.e., throttling expansion) is irreversible because of frictional resistance to flow. Increase of entropy also shows that expansion from point 2 to point 3 is irreversible.
+
+
+disp("(b) Using Mollier chart")
+h1=2692; //kJ/kg
+h2=2560; //kJ/kg
+s1=6.23; //kJ/kg K
+s2=s1;
+s3=8.3; //kJ/kg K
+
+disp("(i) Change in entropy =")
+ds=s3-s1;
+disp(ds)
+disp("kJ/kg K")
+
+
+disp("(ii) Change in enthalpy =")
+dh=h2-h1;
+disp(dh)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH4/EX4.64/64.sce b/551/CH4/EX4.64/64.sce new file mode 100755 index 000000000..8a566ef3a --- /dev/null +++ b/551/CH4/EX4.64/64.sce @@ -0,0 +1,17 @@ +clc
+V1=5.5; //m^3
+p1=16*10^5; //Pa
+T1=315; //K
+V2=V1;
+p2=12*10^5; //Pa
+R=0.287*10^3;
+y=1.4;
+
+m1=p1*V1/R/T1;
+T2=T1*(p2/p1)^((y-1)/y);
+
+m2=p2*V2/R/T2;
+disp("Mass of air which left the receiver=")
+m=m1-m2;
+disp(m)
+disp("kg")
\ No newline at end of file diff --git a/551/CH4/EX4.65/65.sce b/551/CH4/EX4.65/65.sce new file mode 100755 index 000000000..df54e6221 --- /dev/null +++ b/551/CH4/EX4.65/65.sce @@ -0,0 +1,20 @@ +clc
+cp=1; //kJ/kg.K
+cv=0.711; //kJ/kg.K
+V1=1.6; //m^3
+V2=V1;
+p1=5*10^5; //Pa
+T1=373; //K
+p2=1*10^5; //Pa
+R=287;
+y=1.4;
+
+m1=p1*V1/R/T1;
+T2=T1*(p2/p1)^((y-1)/y);
+m2=p2*V2/R/T2;
+KE=(m1*cv*T1)-(m2*cv*T2)-(m1-m2)*cp*T2;
+disp("Kinetic energy of discharge air =")
+disp(KE)
+disp("kJ")
+
+disp("This is the exact answer when using proper value of cv")
\ No newline at end of file diff --git a/551/CH4/EX4.66/66.sce b/551/CH4/EX4.66/66.sce new file mode 100755 index 000000000..12a8c7662 --- /dev/null +++ b/551/CH4/EX4.66/66.sce @@ -0,0 +1,52 @@ +clc
+//For oxygen
+cpa=0.88; //kJ/kg K
+Ra=0.24; //kJ/kg K
+V1a=0.035; //m^3
+p1a=4.5; //bar
+T1a=333; //K
+V2a=0.07; //m^3
+
+//For methane
+V1b=0.07; //m^3
+V2b=0.035; //m^3
+p1b=4.5; //bar
+T1b=261; //K
+cpb=1.92; //kJ/kg K
+Rb=0.496; //kJ/kg K
+
+yb=cpb/(cpb-Rb); //for methane
+cva=cpa-Ra; //for oxygen
+
+disp("(i) Final state condition")
+
+p2b=p1b*(V1b/V2b)^yb;
+disp("p2 for methane =")
+disp(p2b)
+disp("bar")
+
+T2b=p2b*V2b*T1b/p1b/V1b;
+disp("T2 for methane =")
+disp(T2b)
+disp("K")
+
+p2a=p2b;
+
+T2a=p2a*V2a/p1a/V1a*T1a;
+disp("T2 for oxygen =")
+disp(T2a)
+disp("K")
+
+Wb=(p1b*V1b - p2b*V2b)/(yb-1)*100; //kJ
+
+disp("(ii) Work done by the piston ")
+disp("The piston will be in virtual equilibrium and hence zero work is effected by the piston.")
+
+Wa=-Wb;
+
+ma=p1a*V1a/Ra/T1a*10^2;
+
+Q=ma*cva*(T2a-T1a) + Wa;
+disp("(iii) Heat transferred to oxygen =")
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.7/7.sce b/551/CH4/EX4.7/7.sce new file mode 100755 index 000000000..0a9620e1e --- /dev/null +++ b/551/CH4/EX4.7/7.sce @@ -0,0 +1,10 @@ +clc
+W_12=-82; //kJ
+Q_12=-45; //kJ
+dU_12=Q_12 - W_12;
+W_21=100; //kJ
+dU_21=-dU_12;
+Q_21=dU_21 + W_21;
+disp("Heat added to the system = ")
+disp(Q_21)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.8/8.sce b/551/CH4/EX4.8/8.sce new file mode 100755 index 000000000..430763545 --- /dev/null +++ b/551/CH4/EX4.8/8.sce @@ -0,0 +1,12 @@ +clc
+Q2=9000; //kJ
+Q1=3000; //kJ
+Q=Q1-Q2;
+W=0;
+dU=W-Q;
+disp("Work done = ")
+disp(W)
+
+disp("Change in internal energy = ")
+disp(dU)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH4/EX4.9/9.sce b/551/CH4/EX4.9/9.sce new file mode 100755 index 000000000..640186906 --- /dev/null +++ b/551/CH4/EX4.9/9.sce @@ -0,0 +1,23 @@ +m=20; //kg
+g=9.81; //m/s^2
+z2=0;
+z1=15;
+
+disp("(i) When the stone is about to enter the water")
+Q=0
+W=0
+dU=0
+PE=m*g*(z2-z1)
+KE=-PE
+
+disp("(ii) When the stone dips into the tank and comes to rest")
+Q=0
+W=0
+KE=0
+PE=m*g*(z2-z1)
+dU=-PE
+
+disp("(iii) When the water and stone come to their initial temperature")
+W=0
+KE=0
+Q=-dU
\ No newline at end of file diff --git a/551/CH5/EX5.1/1.sce b/551/CH5/EX5.1/1.sce new file mode 100755 index 000000000..93d135ed7 --- /dev/null +++ b/551/CH5/EX5.1/1.sce @@ -0,0 +1,15 @@ +clc
+Q1=1500/60; //kJ/s
+W=8.2; //kW
+
+disp("(i) Thermal efficiency")
+n=W/Q1;
+disp("n=")
+disp(n)
+
+
+disp("(ii) Rate of heat rejection")
+Q2=Q1-W;
+disp("Q2=")
+disp(Q2)
+disp("kW")
\ No newline at end of file diff --git a/551/CH5/EX5.10/10.sce b/551/CH5/EX5.10/10.sce new file mode 100755 index 000000000..a28d027f5 --- /dev/null +++ b/551/CH5/EX5.10/10.sce @@ -0,0 +1,11 @@ +clc
+one_ton_of_refrigeration=210; //kJ/min
+Cooling_required=40*(one_ton_of_refrigeration); //kJ/min
+T1=303; //K
+T2=238; //K
+COP_refrigerator=T2/(T1-T2);
+COP_actual=0.20*COP_refrigerator;
+W=Cooling_required/COP_actual/60;
+disp("power required = ")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH5/EX5.11/11.sce b/551/CH5/EX5.11/11.sce new file mode 100755 index 000000000..c9c5ff9ef --- /dev/null +++ b/551/CH5/EX5.11/11.sce @@ -0,0 +1,23 @@ +clc
+E=12000; //kJ/min
+
+T2=308; //K
+
+// Source 1
+T1=593; //K
+n1=1-T2/T1;
+
+// Source 2
+T1=343; //K
+n2=1-T2/T1;
+
+W1=E*n1;
+disp("W1 =")
+disp(W1)
+
+W2=E*n2;
+disp("W2 =")
+disp(W2)
+
+disp("Thus, choose source 2.")
+disp("The source 2 is selected even though efficiency in this case is lower, because the criterion for selection is the larger output.")
\ No newline at end of file diff --git a/551/CH5/EX5.12/12.sce b/551/CH5/EX5.12/12.sce new file mode 100755 index 000000000..a85cfbe6d --- /dev/null +++ b/551/CH5/EX5.12/12.sce @@ -0,0 +1,34 @@ +clc
+T1=973; //K
+T2=323; //K
+T3=248; //K
+
+Q1=2500; //kJ
+W=400; //kJ
+
+disp("(i)Heat rejection to the 50°C reservoir")
+n_max=1-T2/T1;
+W1=n_max*Q1;
+COP_max=T3/(T2-T3);
+W2=W1-W;
+Q4=COP_max*W2;
+COP1=Q4/W2;
+Q3=Q4+W2;
+Q2=Q1-W1;
+disp("Heat rejection to the 50°C reservoir=")
+disp(Q2+Q3)
+disp("kJ")
+
+
+disp("(ii)Heat rejected to 50°C reservoir ")
+n=0.45*n_max;
+W1=n*Q1;
+W2=W1-W;
+COP2=0.45*COP1;
+Q4=W2*COP2;
+Q3=Q4+W2;
+Q2=Q1-W1;
+
+disp("Heat rejected to 50°C reservoir=")
+disp(Q2+Q3)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.13/13.sce b/551/CH5/EX5.13/13.sce new file mode 100755 index 000000000..ebace8449 --- /dev/null +++ b/551/CH5/EX5.13/13.sce @@ -0,0 +1,29 @@ +clc
+T1=298; //K
+T2=273; //K
+Q1=24; //kJ/s
+T3=653; //K
+COP=T1/(T1-T2);
+disp("(i) determine COP and work input required")
+
+disp("Coefficient of performance = ")
+disp(COP)
+
+COP_ref=T2/(T1-T2);
+W=Q1/COP_ref;
+disp("Work input required = ")
+disp(W)
+disp("kW")
+
+
+disp("(ii)Determine overall COP of the system ")
+Q4=T1*W/(T3-T1);
+Q3=Q4+W;
+Q2=Q1+W;
+COP=Q1/Q3;
+disp("COP=")
+disp(COP)
+
+COP_overall=(Q2+Q4)/Q3;
+disp("Overall COP=")
+disp(COP_overall)
\ No newline at end of file diff --git a/551/CH5/EX5.14/14.sce b/551/CH5/EX5.14/14.sce new file mode 100755 index 000000000..8ad676512 --- /dev/null +++ b/551/CH5/EX5.14/14.sce @@ -0,0 +1,23 @@ +clc
+T_e1=493; //K
+T_e2=298; //K
+T_p1=298; //K
+T_p2=273; //K
+Amt=15; //tonnes produced per day
+h=334.5; //kJ/kg
+Q_abs=44500; //kJ/kg
+Q_p2=Amt*10^3*h/24/60;
+COP_hp=T_p2/(T_p1-T_p2);
+W=Q_p2/COP_hp/60;
+disp("(i)Power developed by the engine = ")
+disp(W)
+disp("kW")
+
+
+disp("(ii) Fuel consumed per hour")
+n_carnot=1-(T_e2/T_e1);
+Q_e1=W/n_carnot*3600; //kJ/h
+fuel_consumed=Q_e1/Q_abs;
+disp("Quantity of fuel consumed/hour = ")
+disp(fuel_consumed)
+disp("kg/h")
\ No newline at end of file diff --git a/551/CH5/EX5.15/15.sce b/551/CH5/EX5.15/15.sce new file mode 100755 index 000000000..bd1e2c830 --- /dev/null +++ b/551/CH5/EX5.15/15.sce @@ -0,0 +1,10 @@ +clc
+T1=550; //K
+T3=350; //K
+// W=Q2*((T1-T2)/T2)
+// W=Q2((T2-T3)/T2)
+// From this we get following expression
+T2=(T1+T3)/2;
+disp("Intermediate temperature =")
+disp(T2)
+disp("K")
\ No newline at end of file diff --git a/551/CH5/EX5.16/16.sce b/551/CH5/EX5.16/16.sce new file mode 100755 index 000000000..dd7616b6b --- /dev/null +++ b/551/CH5/EX5.16/16.sce @@ -0,0 +1,21 @@ +clc
+T1=600; //K
+T2=300; //K
+
+
+disp("(i) When Q1=Q2")
+T3=2*T1/(T1/T2+1);
+disp("T3=")
+disp(T3)
+disp("K")
+
+
+disp("(ii) Efficiency of Carnot engine and COP of carnot refrigerator")
+n=(T1-T3)/T1; //carnot engine
+COP=T2/(T3-T2); //refrigerator
+
+disp("Efficiency of carnot engine = ")
+disp(n)
+
+disp("COP of carnot refrigerator = ")
+disp(COP)
\ No newline at end of file diff --git a/551/CH5/EX5.17/17.sce b/551/CH5/EX5.17/17.sce new file mode 100755 index 000000000..6f6c3f00a --- /dev/null +++ b/551/CH5/EX5.17/17.sce @@ -0,0 +1,11 @@ +clc
+T3=278; //K
+T2=350; //K
+T4=T2;
+T1=1350; //K
+
+Q1=100/[((T4/T1)*(T1-T2)/(T4-T3))+T2/T1]; //Q4+Q2=100; Q4=Q1*((T4/T1)*(T1-T2)/(T4-T3)); Q2=T2/T1*Q1;
+
+disp("Q1=")
+disp(Q1)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.18/18.sce b/551/CH5/EX5.18/18.sce new file mode 100755 index 000000000..67e830809 --- /dev/null +++ b/551/CH5/EX5.18/18.sce @@ -0,0 +1,22 @@ +clc
+Q1=300; //kJ/s
+T1=290; //0C
+T2=8.5; //0C
+disp("let ΣdQ/T = A")
+
+disp("(i) 215 kJ/s are rejected")
+Q2=215; //kJ/s
+A= Q1/(T1+273) - Q2/(T2+273)
+disp("Since, A<0, Cycle is irreversible.")
+
+
+disp("(ii) 150 kJ/s are rejected")
+Q2=150; //kJ/s
+A= Q1/(T1+273) - Q2/(T2+273)
+disp("Since A=0, cycle is reversible")
+
+
+disp("(iii) 75 kJ/s are rejected.")
+Q2=75; //kJ/s
+A= Q1/(T1+273) - Q2/(T2+273)
+disp("Since A>0, cycle is impossible")
\ No newline at end of file diff --git a/551/CH5/EX5.19/19.sce b/551/CH5/EX5.19/19.sce new file mode 100755 index 000000000..4b5c65c31 --- /dev/null +++ b/551/CH5/EX5.19/19.sce @@ -0,0 +1,14 @@ +clc
+P1=0.124*10^5; //N/m^2
+T1=433; //K
+T2=323; //K
+h_f1=687; //kJ/kg
+h2=2760; //kJ/kg
+h3=2160; //kJ/kg
+h_f4=209; //kJ/kg
+Q1=h2-h_f1;
+Q2=h_f4-h3;
+disp("Let A=ΣdQ/T")
+A=Q1/T1+Q2/T2;
+disp(A)
+disp("A<0. Hence classius inequality is verified")
\ No newline at end of file diff --git a/551/CH5/EX5.2/2.sce b/551/CH5/EX5.2/2.sce new file mode 100755 index 000000000..d8047f9ed --- /dev/null +++ b/551/CH5/EX5.2/2.sce @@ -0,0 +1,9 @@ +clc
+Q_12=30; //kJ
+W_12=60; //kJ
+dU_12=Q_12-W_12;
+Q_21=0;
+W_21=Q_21+dU_12;
+disp("W_21 =")
+disp(W_21)
+disp("Thus 30 kJ work has to be done on the system to restore it to original state, by adiabatic process.")
\ No newline at end of file diff --git a/551/CH5/EX5.20/20.sce b/551/CH5/EX5.20/20.sce new file mode 100755 index 000000000..88b1aee37 --- /dev/null +++ b/551/CH5/EX5.20/20.sce @@ -0,0 +1,15 @@ +clc
+T1=437; //K
+T2=324; //K
+h2=2760; //kJ/kg
+h1=690; //kJ/kg
+h3=2360; //kJ/kg
+h4=450; //kJkg
+
+Q1=h2-h1;
+Q2=h4-h3;
+
+disp("Let A=ΣdQ/T")
+A=Q1/T1 + Q2/T2;
+disp(A)
+disp("Since A<0, Classius inequality is verified")
\ No newline at end of file diff --git a/551/CH5/EX5.21/21.sce b/551/CH5/EX5.21/21.sce new file mode 100755 index 000000000..5f7e6bcd9 --- /dev/null +++ b/551/CH5/EX5.21/21.sce @@ -0,0 +1,20 @@ +clc
+T0=273; //K
+T1=673; //K
+T2=298; //K
+m_w=10; //kg
+T3=323; //K
+c_pw=4186; //kJ/kg.K
+disp("Let C=mi*cpi")
+C=m_w*c_pw*(T3-T2)/(T1-T3);
+
+S_iT1=C*log(T1/T0); // Entropy of iron at 673 K
+S_wT2=m_w*c_pw*log(T2/T0); //Entropy of water at 298 K
+S_iT3=C*log(T3/T0); //Entropy of iron at 323 K
+S_wT3=m_w*c_pw*log(T3/T0); //Entropy of water at 323 K
+
+dS_i=S_iT3 - S_iT1;
+dS_w=S_wT3 - S_wT2;
+dS_net=dS_i + dS_w
+
+disp("Since dS>0, process is irreversible")
\ No newline at end of file diff --git a/551/CH5/EX5.23/23.sce b/551/CH5/EX5.23/23.sce new file mode 100755 index 000000000..0c782dcb9 --- /dev/null +++ b/551/CH5/EX5.23/23.sce @@ -0,0 +1,30 @@ +clc
+T1=293; //K
+V1=0.025; //m^3
+V3=V1;
+p1=1.05*10^5; //N/m^2
+p2=4.5*10^5; //N/m^2
+R=0.287*10^3;
+cv=0.718;
+cp=1.005;
+T3=293; //K
+
+disp("(i)Net heat flow")
+m=p1*V1/R/T1;
+T2=p2/p1*T1;
+Q_12=m*cv*(T2-T1);
+Q_23=m*cp*(T3-T2)
+
+disp("Net heat flow = ")
+Q_net=Q_12+Q_23;
+disp(Q_net)
+disp("kJ")
+
+
+disp("(ii) Net entropy change")
+dS_32=m*cp*log(T2/T1);
+dS_12=m*cv*log(T2/T1);
+dS_31=dS_32 - dS_12;
+disp("Decrease in entropy = ")
+disp(dS_31)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH5/EX5.24/24.sce b/551/CH5/EX5.24/24.sce new file mode 100755 index 000000000..100ce8a93 --- /dev/null +++ b/551/CH5/EX5.24/24.sce @@ -0,0 +1,70 @@ +clc
+p1=1.05*10^5; //N/m^2
+V1=0.04; //m^3
+T1=288; //K
+p2=4.8*10^5;
+T2=T1;
+R0=8314;
+M=28;
+
+
+disp("(i) The change of entropy =")
+R=R0/M;
+m=p1*V1/R/T1;
+dS=m*R*log(p1/p2)
+disp("Decrease in entropy =")
+disp(-dS)
+disp("J/K")
+
+
+disp("(ii)Heat rejected = ")
+Q=T1*(-dS);
+disp("Q=")
+disp(Q)
+disp("J")
+
+
+W=Q;
+disp("Work done = ")
+disp(W)
+disp("J")
+
+V2=p1*V1/p2;
+v1=V1/m; //specific volume
+v2=V2/m; //specific volume
+
+v=v2:0.01:v1;
+function p=f(v)
+ p=p1*v1/v
+endfunction
+
+plot(v,f)
+
+p=p1
+plot(v,p,'--')
+
+p=[0 p2]
+v=[v2 v2]
+plot(v,p,'--')
+
+p=[0 p1]
+v=[v1 v1]
+plot(v,p,'--')
+
+xtitle("p-v diagram", "v(m^3/kg)", "p(N/m^2)")
+
+xset('window', 1)
+
+T=[288 288]
+s=[10 (10-dS)]
+plot(s,T)
+
+s=[10 10]
+T=[0 288]
+plot(s,T,'--')
+
+s=[(10-dS) (10-dS)]
+T=[0 288]
+plot(s,T,'--')
+
+xtitle("T-s diagram", "s(kJ/kg K)", "T(K)")
\ No newline at end of file diff --git a/551/CH5/EX5.25/25.sce b/551/CH5/EX5.25/25.sce new file mode 100755 index 000000000..3185d6c39 --- /dev/null +++ b/551/CH5/EX5.25/25.sce @@ -0,0 +1,11 @@ +clc
+R=287; //kJ/kg.K
+dU=0;
+W=0;
+Q=dU+W;
+
+dS=R*log(2); //v2/v1=2
+
+disp("Change in entropy = ")
+disp(dS)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH5/EX5.26/26.sce b/551/CH5/EX5.26/26.sce new file mode 100755 index 000000000..0110b683f --- /dev/null +++ b/551/CH5/EX5.26/26.sce @@ -0,0 +1,19 @@ +clc
+m=0.04; //kg
+p1=1*10^5; //N/m^2
+T1=293; //K
+p2=9*10^5; //N/m^2
+V2=0.003; //m^3
+cp=0.88; //kJ/kg.K
+R0=8314;
+M=44;
+
+R=R0/M;
+T2=p2*V2/m/R;
+ds_2A=R/10^3*log(p2/p1);
+ds_1A=cp*log(T2/T1);
+ds_21=ds_2A - ds_1A;
+dS_21=m*ds_21;
+disp("Decrease in entropy=")
+disp(dS_21)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH5/EX5.27/27.sce b/551/CH5/EX5.27/27.sce new file mode 100755 index 000000000..463bd18bc --- /dev/null +++ b/551/CH5/EX5.27/27.sce @@ -0,0 +1,21 @@ +clc
+p1=7*10^5; //N/m^2
+T1=873; //K
+p2=1.05*10^5; //N/M62
+n=1.25;
+m=1; //kg
+R=0.287;
+cp=1.005;
+T2=T1*(p2/p1)^((n-1)/n);
+
+// At constant temperature from 1 to A
+ds_1A=R*log(p1/p2);
+
+// At constant pressure from A to 2
+ds_2A=cp*log(T1/T2);
+
+
+ds_12=ds_1A - ds_2A;
+disp("Increase in entropy = ")
+disp(ds_12)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH5/EX5.28/28.sce b/551/CH5/EX5.28/28.sce new file mode 100755 index 000000000..92e830c06 --- /dev/null +++ b/551/CH5/EX5.28/28.sce @@ -0,0 +1,20 @@ +clc
+p1=7*10^5; //Pa
+T1=733; //K
+p2=1.012*10^5; //Pa
+T2a=433; //K
+y=1.4;
+cp=1.005;
+
+disp("(i) To prove that the process is irreversible")
+T2=T1*(p2/p1)^((y-1)/y);
+disp("T2 =")
+disp(T2)
+disp("But the actual temperature is 433K at th epressure of 1.012 bar, Hence the process is irreversible. Proved.")
+
+
+disp("(ii) Change of entropy per kg of air")
+ds=cp*log(T2a/T2);
+disp("Increase of entropy=")
+disp(ds)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH5/EX5.29/29.sce b/551/CH5/EX5.29/29.sce new file mode 100755 index 000000000..683ec0905 --- /dev/null +++ b/551/CH5/EX5.29/29.sce @@ -0,0 +1,38 @@ +clc
+V1=0.3; //m^3
+p1=4*10^5; //N/m^2
+V2=0.08; //m^3
+n=1.25;
+p2=p1*(V1/V2)^n;
+
+disp("(i) Change in enthalpy")
+dH=n*(p2*V2-p1*V1)/(n-1)/10^3;
+disp("dH=")
+disp(dH)
+disp("kJ")
+
+
+disp("(ii) Change in internal energy")
+dU=dH-(p2*V2 - p1*V1)/10^3;
+disp("dU=")
+disp(dU)
+disp("kJ")
+
+
+disp("(iii) Change in entropy")
+dS=0;
+disp("dS")
+disp(dS)
+
+
+disp("(iv)Heat transfer")
+Q=0;
+disp("Q=")
+disp(Q)
+
+
+disp("(v) Work transfer")
+W=Q-dU;
+disp("W=")
+disp(W)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.3/3.sce b/551/CH5/EX5.3/3.sce new file mode 100755 index 000000000..17fc79b34 --- /dev/null +++ b/551/CH5/EX5.3/3.sce @@ -0,0 +1,11 @@ +clc
+Q2=12000; //kJ/h
+W=0.75*60*60; //kJ/h
+COP=Q2/W;
+disp("Coefficient of performance")
+disp(COP)
+
+Q1=Q2+W;
+disp("heat transfer rate=")
+disp(Q1)
+disp("kJ/h")
\ No newline at end of file diff --git a/551/CH5/EX5.30/30.sce b/551/CH5/EX5.30/30.sce new file mode 100755 index 000000000..7a23f05f0 --- /dev/null +++ b/551/CH5/EX5.30/30.sce @@ -0,0 +1,36 @@ +clc
+m=20; //kg
+p1=4*10^5; //Pa
+p2=8*10^5; //Pa
+V1=4; //m^3
+V2=V1;
+cp=1.04; //kJ/kg.K
+cv=0.7432; //kJ/kg.K
+R=cp-cv;
+T1=p1*V1/R/1000; //kg.K; T=mass*temperature
+T2=p2*V2/R/1000; //kg.K
+
+
+disp("(i) Change in internal energy")
+dU=cv*(T2-T1);
+disp("dU=")
+disp(dU)
+disp("kJ")
+
+
+disp("(ii) Work done")
+Q=0;
+W=Q-dU;
+disp("W")
+disp(W)
+disp("kJ")
+
+
+disp("(iii) Heat transferred = ")
+disp(Q)
+
+
+disp("(iv) Change in entropy =")
+dS=m*cv*log(T2/T1);
+disp(dS)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH5/EX5.31/31.sce b/551/CH5/EX5.31/31.sce new file mode 100755 index 000000000..c08d4b123 --- /dev/null +++ b/551/CH5/EX5.31/31.sce @@ -0,0 +1,33 @@ +clc
+V1=5; //m^3
+p1=2*10^5; //Pa
+T1=300; //K
+p2=6*10^5; //Pa
+p3=2*10^5; //Pa
+R=287;
+n=1.3;
+y=1.4;
+
+m=p1*V1/R/T1;
+T2=T1*(p2/p1)^((n-1)/n);
+T3=T2*(p3/p2)^((y-1)/y);
+W_12=m*R*(T1-T2)/(n-1)/1000; //polytropic compression
+W_23=m*R*(T2-T3)/(y-1)/1000; //Adiabatic expansion
+
+W_net=W_12+W_23;
+disp("Net work done on the air = ")
+disp(-W_net)
+
+T=[T1 310 320 330 340 350 360 370 380 T2];
+function s=f(T)
+ s=(y-n)/(y-1)/(1-n)*R/10^3*log(T);
+endfunction
+s=[f(T1) f(310) f(320) f(330) f(340) f(350) f(360) f(370) f(380) f(T2)]
+plot(s,T)
+
+T=[T2 T3];
+s=[f(T2) f(T2)];
+plot(s,T,'r')
+
+xtitle("T-s diagram", "s(kJ/kg K)", "T(K)")
+legend("p*v^1.3=constant", "p*v^y=constant")
\ No newline at end of file diff --git a/551/CH5/EX5.32/32.sce b/551/CH5/EX5.32/32.sce new file mode 100755 index 000000000..93a258f82 --- /dev/null +++ b/551/CH5/EX5.32/32.sce @@ -0,0 +1,25 @@ +clc
+V1=0.004; //m^3
+p1=1*10^5; //Pa
+T1=300; //K
+T2=400; //K
+y=1.4;
+M=28;
+R0=8.314;
+R=R0/M;
+
+
+disp("(i) The heat supplied")
+m=p1*V1/R/1000/T1; //kg
+cv=R/(y-1);
+Q=m*cv*(T2-T1);
+disp("Q")
+disp(Q)
+disp("kJ")
+
+
+disp("(ii) The entropy change")
+dS=m*cv*log(T2/T1);
+disp("dS=")
+disp(dS)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH5/EX5.33/33.sce b/551/CH5/EX5.33/33.sce new file mode 100755 index 000000000..ebc9d1591 --- /dev/null +++ b/551/CH5/EX5.33/33.sce @@ -0,0 +1,23 @@ +clc
+V1=0.05; //m^3
+p1=1*10^5; //Pa
+T1=280; //K
+p2=5*10^5; //Pa
+
+disp("(i) Change in entropy")
+R0=8.314;
+M=28;
+R=R0/M;
+m=p1*V1/R/T1/1000;
+
+
+dS=m*R*log(p1/p2);
+disp("dS=")
+disp(dS)
+disp("kJ/K")
+
+disp("(ii)Work done")
+Q=T1*dS;
+disp("Q=")
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.34/34.sce b/551/CH5/EX5.34/34.sce new file mode 100755 index 000000000..27d917859 --- /dev/null +++ b/551/CH5/EX5.34/34.sce @@ -0,0 +1,43 @@ +clc
+R=0.287; //kJ/kg.K
+m=1; //kg
+p1=8*10^5; //Pa
+p2=1.6*10^5; //Pa
+T1=380; //K
+n=1.2;
+y=1.4;
+
+
+disp("(i) Final specific volume and temperature")
+v1=R*T1/p1*10^3; //m^3/kg
+v2=v1*(p1/p2)^(1/n);
+T2=T1*(p2/p1)^((n-1)/n);
+disp("v2=")
+disp(v2)
+disp("m^3/kg")
+disp("T2=")
+disp(T2)
+
+
+disp("(ii) Change of internal energy, work done and heat interaction")
+dU=R/(y-1)*(T2-T1);
+disp("dU=")
+disp(dU)
+disp("kJ/kg")
+
+W=R*(T1-T2)/(n-1);
+disp("W=")
+disp(W)
+disp("kJ/kg")
+
+Q=dU + W;
+disp("Q=")
+disp(Q)
+disp("kJ/kg")
+
+
+disp("(iii) Change in entropy")
+dS=R/(y-1)*log(T2/T1) + R*log(v2/v1)
+disp("dS=")
+disp(dS)
+disp("kJ/kg.K")
\ No newline at end of file diff --git a/551/CH5/EX5.35/35.sce b/551/CH5/EX5.35/35.sce new file mode 100755 index 000000000..a8c2d3501 --- /dev/null +++ b/551/CH5/EX5.35/35.sce @@ -0,0 +1,56 @@ +clc
+y=1.4;
+cv=0.718; //kJ/kg.K
+m=1; //kg
+T1=290; //K
+n=1.3;
+r=16;
+y=1.4;
+
+T2=T1*(r)^(n-1);
+
+disp("(a)")
+
+T=[T1 300 310 320 330 340 350 360 370 380 390 400 410 420 430 440 450 460 470 480 490 500 510 520 530 540 550 560 570 580 590 600 610 620 630 640 650 660 T2];
+function s=f(T)
+ s=(y-n)*cv/(1-n)/10^3*log(T);
+endfunction
+s=[f(T1) f(300) f(310) f(320) f(330) f(340) f(350) f(360) f(370) f(380) f(390) f(400) f(410) f(420) f(430) f(440) f(450) f(460) f(470) f(480) f(490) f(500) f(510) f(520) f(530) f(540) f(550) f(560) f(570) f(580) f(590) f(600) f(610) f(620) f(630) f(640) f(650) f(660) f(T2)];
+plot(s,T)
+
+T=[0 T2];
+s=[f(T2) f(T2)];
+plot(s,T,'r--')
+
+T=[0 T1];
+s=[f(T1) f(T1)];
+plot(s,T,'r--')
+
+T=[T1 T2];
+s=[f(T1) f(T2)];
+plot(s,T,'r--')
+
+xtitle("T-s diagram", "s", "T")
+legend("p*v^n=c")
+
+//Heat transferred = Area of trapezium = Base*mean ordinate
+
+//Heat transferred=dS*(T1+T2)/2
+//Hence we get
+disp("Entropy change=Heat transferred/Mean absolute temperature")
+
+disp("(b)Entropy change")
+dS=cv*((n-y)/(n-1))*log(T2/T1);
+disp("dS=")
+disp(dS)
+disp("kJ/kg.K")
+disp("There is decrease in entropy")
+
+Q=cv*((y-n)/(n-1))*(T1-T2);
+Tmean = (T1+T2)/2;
+dS_app=Q/Tmean;
+
+%error=((-dS) - (-dS_app))/(-dS) * 100;
+disp("%age error =")
+disp(%error)
+disp("%")
\ No newline at end of file diff --git a/551/CH5/EX5.36/36.sce b/551/CH5/EX5.36/36.sce new file mode 100755 index 000000000..a26251453 --- /dev/null +++ b/551/CH5/EX5.36/36.sce @@ -0,0 +1,47 @@ +clc
+cp=1.005; //kJ/kg.K
+R=0.287; //kJ/kg.K
+V1=1.2; //m^3
+p1=1*10^5; //Pa
+p2=p1;
+T1=300; //K
+T2=600; //K
+T3=T1;
+p1=1*10^5; //Pa
+cv=cp-R;
+
+disp("(i) The net heat flow")
+m=p1*V1/R/1000/T1; //kg
+Q=m*R*(T2-T1);
+disp("Q=")
+disp(Q)
+disp("kJ")
+
+
+disp("(ii) The overall change in entropy")
+dS_12=m*cp*log(T2/T1);
+dS_23=m*(cp-R)*log(T3/T2); //cv=cp-R
+dS_overall=dS_12+dS_23;
+disp("Overall change in entropy=")
+disp(dS_overall)
+disp("kJ/K")
+
+
+s=sqrt(300):0.1:sqrt(600);
+T=s^2;
+plot(s,T)
+
+s=22.18:0.1:sqrt(600);
+T=10*(s-16.725)^2;
+plot(s,T,'r')
+
+s=[17 25];
+T=[600 600];
+plot(s,T,'--')
+
+s=[17 25];
+T=[300 300];
+plot(s,T,'--')
+
+xtitle("T-s diagram", "S", "T")
+legend("p=C", "V=C")
diff --git a/551/CH5/EX5.37/37.sce b/551/CH5/EX5.37/37.sce new file mode 100755 index 000000000..a6d8a66cc --- /dev/null +++ b/551/CH5/EX5.37/37.sce @@ -0,0 +1,68 @@ +clc
+cv=0.718; //kJ/kg.K
+R=0.287; //kJ/kg.K
+p1=1*10^5; //Pa
+T1=300; //K
+V1=0.018; //m^3
+p2=5*10^5; //Pa
+T3=T1;
+cp=cv+R;
+p3=p2;
+
+m=p1*V1/R/T1/1000; //kg
+T2=T1*p2/p1;
+
+disp("(i) constant volume process")
+disp("dS=")
+dS_12=m*cv*log(T2/T1);
+disp(dS_12)
+disp("kJ/K")
+
+disp("(ii) Constant prssure process ")
+disp("dS=")
+dS_23=m*cp*log(T3/T2);
+disp(dS_23)
+disp("kJ/K")
+
+disp("(iii) Isothermal process")
+disp("dS=")
+dS_31=m*R*log(p3/p1);
+disp(dS_31)
+disp("kJ/K")
+
+disp("T-s diagram")
+s=sqrt(300):0.1:sqrt(600);
+T=s^2;
+plot(s,T)
+
+s=22.18:0.1:sqrt(600);
+T=10*(s-16.725)^2;
+plot(s,T,'r')
+
+s=[sqrt(300) 22.18];
+T=[300 300];
+plot(s,T,'g')
+
+xtitle("T-s diagram", "S", "T")
+legend("p=C", "V=C", "T=C")
+
+disp("p-V diagram")
+xset('window',1)
+
+V=[0.018 0.018];
+p=[1 5];
+plot(V,p)
+
+p=[5 5];
+V=[0.0036 0.018];
+plot(V,p,'r')
+
+V=0.0036:0.0001:0.018;
+function p=f(V)
+ p=1*0.018/V;
+endfunction
+
+plot(V,f,'g')
+
+xtitle("p-V diagram", "V", "p")
+legend("V=C","p=C","T=C")
\ No newline at end of file diff --git a/551/CH5/EX5.39/39.sce b/551/CH5/EX5.39/39.sce new file mode 100755 index 000000000..ba991b137 --- /dev/null +++ b/551/CH5/EX5.39/39.sce @@ -0,0 +1,9 @@ +clc
+m=4; //kg
+T1=400; //K
+T2=500; //K
+
+dS=integrate('m*(0.48+0.0096*T)/T', 'T', T1,T2);
+disp("dS=")
+disp(dS)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.4/4.sce b/551/CH5/EX5.4/4.sce new file mode 100755 index 000000000..3c137f740 --- /dev/null +++ b/551/CH5/EX5.4/4.sce @@ -0,0 +1,10 @@ +clc
+T2=261; //K
+T1=308; //K
+Q2=2; //kJ/s
+Q1=Q2*(T1/T2);
+W=Q1-Q2;
+
+disp("Least power required to pump the heat continuosly")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH5/EX5.40/40.sce b/551/CH5/EX5.40/40.sce new file mode 100755 index 000000000..a16ab29fd --- /dev/null +++ b/551/CH5/EX5.40/40.sce @@ -0,0 +1,13 @@ +clc
+p1=1*10^5; //Pa
+T1=273; //K
+p2=25*10^5; //Pa
+T2=750; //K
+R=0.29; //kJ/kg.K ; cp=0.85+0.00025*T; cv=0.56+0.00025*T; R=cp-cv;
+v2=R*T2/p2;
+v1=R*T1/p1;
+ds=integrate('(0.56+0.00025*T)/T', 'T', T1, T2) + integrate('R/v', 'v', v1, v2);
+
+disp("ds=")
+disp(ds)
+disp("kJ/kg K")
\ No newline at end of file diff --git a/551/CH5/EX5.41/41.sce b/551/CH5/EX5.41/41.sce new file mode 100755 index 000000000..6f8f41ce1 --- /dev/null +++ b/551/CH5/EX5.41/41.sce @@ -0,0 +1,39 @@ +clc
+cv=0.715; //kJ/kg K
+R=0.287; //kJ/kg K
+V_A=0.25; //m^3
+p_Ai=1.4; //bar
+T_Ai=290; //K
+V_B=0.25; //m^3
+p_Bi=4.2; //bar
+T_Bi=440; //K
+
+disp("(i) Final equilibrium temperature")
+m_A=p_Ai * 10^5 * V_A / R / 1000/ T_Ai; //kg
+m_B=p_Bi * 10^5 * V_B / R / 1000/ T_Bi; //kg
+
+T_f=(m_B * T_Bi + m_A * T_Ai)/(m_A + m_B);
+disp("T_f = ")
+disp(T_f)
+disp("K")
+
+
+disp("(ii) Final pressure on each side of the diaphragm")
+p_Af=p_Ai*T_f/T_Ai;
+disp("p_Af=")
+disp(p_Af)
+disp("bar")
+
+p_Bf=p_Bi*T_f/T_Bi;
+disp("p_Bf=")
+disp(p_Bf)
+disp("bar")
+
+
+disp("(iii) Entropy change of the system")
+dS_A=m_A*cv*log(T_f/T_Ai);
+dS_B=m_B*cv*log(T_f/T_Bi);
+dS_net=dS_A+dS_B;
+disp("Net change of entropy=")
+disp(dS_net)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH5/EX5.42/42.sce b/551/CH5/EX5.42/42.sce new file mode 100755 index 000000000..e942b6209 --- /dev/null +++ b/551/CH5/EX5.42/42.sce @@ -0,0 +1,21 @@ +clc
+cv=1.25; //kJ/kg.K
+T1=530; //K
+v1=0.0624; //m^3/kg
+v2=0.186; //m^3/kg
+dT_31=25; //K
+T3=T1-dT_31; //K
+dT_21=165; //K
+T2=T1-dT_21; //K
+// Path 1-2 : Reversible adiabatic process
+ds_12=0;
+
+// To calculate (s3–s1) a reversible path has to be selected joining 3 and 1.This is achieved by selecting the reversible adiabatic path 1-2 and the reversible constant volume process 2-3.
+
+// Path 1-3 : Adiabatic process
+v3=0.186; //m^3/kg
+v3=v2;
+ds_13=cv*log(T3/T2);
+disp("Chang in entropy = ")
+disp(ds_13)
+disp("kJ/kgK")
\ No newline at end of file diff --git a/551/CH5/EX5.44/44.sce b/551/CH5/EX5.44/44.sce new file mode 100755 index 000000000..d5ac87f49 --- /dev/null +++ b/551/CH5/EX5.44/44.sce @@ -0,0 +1,47 @@ +clc
+T1=500; //K
+T2=400; //K
+T3=300; //K
+Q1=1500; //kJ/min
+W=200; //kJ/min
+
+//Q1/T1 + Q2/T2 + Q3/T3=0
+//Q1+Q2+Q3=W
+//For solving the above two equations we use following method
+//Q2-Q3=-1300
+//Q2/400 - Q3/300 =-1500/500=-3
+
+A=[1,-1;(1/400),(-1/300)];
+B=[(-1300);(-3)];
+X=inv(A)*B;
+Q2=X(1,1);
+disp("Q2 =")
+disp(Q2)
+disp("kJ/min")
+
+Q3=X(2,1);
+disp("Q3 =")
+disp(Q3)
+disp("kJ/min")
+
+disp("(ii) Entropy change ")
+dS1=(-Q1)/T1;
+disp("Entropy change of source 1 =")
+disp(dS1)
+disp("kJ/K")
+
+dS2=(-Q2)/T2;
+disp("Entropy change of sink 2 =")
+disp(dS2)
+disp("kJ/K")
+
+dS3=Q3/T3;
+disp("Entropy change of source 3 =")
+disp(dS3)
+disp("kJ/K")
+
+
+disp("(iii) Net change of the entropy")
+dSnet = dS1 + dS2 + dS3;
+disp("dSnet=")
+disp(dSnet)
\ No newline at end of file diff --git a/551/CH5/EX5.45/45.sce b/551/CH5/EX5.45/45.sce new file mode 100755 index 000000000..c243d8bf3 --- /dev/null +++ b/551/CH5/EX5.45/45.sce @@ -0,0 +1,17 @@ +clc
+T1=250; //K
+T2=125; //K
+//cv=0.0045*T^2
+Q1=integrate('0.045*T^2', 'T', T1, T2);
+dS_system=integrate('0.045*T', 'T', T1, T2);
+
+//dS_reservoir=(Q1-W)/T_resservoir
+
+//dS_universe >= 0
+//But for maximum work done dS_universe=0
+dS_universe=0;
+
+W_max=((-Q1) -T2*(dS_universe-dS_system))/1000;
+disp("W_max=")
+disp(W_max)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.46/46.sce b/551/CH5/EX5.46/46.sce new file mode 100755 index 000000000..d2a33864d --- /dev/null +++ b/551/CH5/EX5.46/46.sce @@ -0,0 +1,16 @@ +clc
+cp=1.005; //kJ/kg K
+T_A=333; //K
+T_B=288; //K
+p_A=140; //kPa
+p_B=110; //kPa
+//h=cp*T
+//v/T=0.287/p
+ds_system=integrate('cp/T', 'T', T_A, T_B) + integrate('0.287/p', 'p', p_A, p_B);
+ds_surr=0;
+ds_universe=ds_system+ds_surr;
+disp("change in entropy of universe = ")
+disp(ds_universe)
+disp("kJ/kgK")
+disp("Since change in entropy of universe from A to B is -ve")
+disp("The flow is from B to A")
\ No newline at end of file diff --git a/551/CH5/EX5.47/47.sce b/551/CH5/EX5.47/47.sce new file mode 100755 index 000000000..5baf3735a --- /dev/null +++ b/551/CH5/EX5.47/47.sce @@ -0,0 +1,14 @@ +clc
+m1=3; //kg
+m2=4; //kg
+T0=273; //K
+T1=80+273; //K
+T2=15+273; //K
+c_pw=4.187; //kJ/kgK
+tm=(m1*T1 + m2*T2)/(m1+m2);
+Si=m1*c_pw*log(T1/T0) + m2*c_pw*log(T2/T0);
+Sf=(m1+m2)*c_pw*log(tm/T0);
+dS=Sf-Si;
+disp("Net change in entropy =")
+disp(dS)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH5/EX5.49/49.sce b/551/CH5/EX5.49/49.sce new file mode 100755 index 000000000..741bf0fe0 --- /dev/null +++ b/551/CH5/EX5.49/49.sce @@ -0,0 +1,40 @@ +clc +m=1; //kg +T1=273; //K +T2=363; //K +c=4.187; + +disp("(a)") +disp("(i) Entropy of water=") +ds_water=m*c*log(T2/T1); +disp(ds_water) +disp("kJ/kgK") + + +disp("(ii) Entropy change of the reservoir ") +Q=m*c*(T2-T1); +ds_reservoir=-Q/T2; +disp("ds_reservoir=") +disp(ds_reservoir) +disp("kJ/K") + + +disp("(iii) Entropy change of universe =") +ds_universe=ds_water+ds_reservoir; +disp(ds_universe) +disp("kJ/K") + + +disp("(b)") +T3=313; //K +ds_water=m*c*(log(T3/T1) + log(T2/T3)); +ds_res1=-m*c*(T3-T1)/T3; +ds_res2=-m*c*(T2-T3)/T2; + +ds_universe=ds_water+ds_res1+ds_res2; +disp("(iii) Entropy change of universe =") +disp(ds_universe) +disp("kJ/K") + +disp("(c) The entropy change of universe would be less and less, if the water is heated in more and more stages, by bringing the water in contact successively with more and more heat reservoirs, each succeeding reservoir being at a higher temperature than the preceding one.") +disp("When water is heated in infinite steps, by bringing in contact with an infinite number of reservoirs in succession, so that at any instant the temperature difference between the water and the reservoir in contact is infinitesimally small, then the entropy change of the universe would be zero and the water would be reversibly heated.")
\ No newline at end of file diff --git a/551/CH5/EX5.5/5.sce b/551/CH5/EX5.5/5.sce new file mode 100755 index 000000000..07398f3b1 --- /dev/null +++ b/551/CH5/EX5.5/5.sce @@ -0,0 +1,15 @@ +clc
+
+disp("(i) Heat abstracted from outside=")
+Q1=2*10^5; //kJ/h
+W=3*10^4; //kJ/h
+Q2=Q1-W;
+disp("Heat abstracted from outside=")
+disp(Q2)
+disp("kJ/h")
+
+
+disp("(ii) Co-efficient of performance")
+COP_hp=Q1/(Q1-Q2);
+disp("Co-efficient of performance=")
+disp(COP_hp)
\ No newline at end of file diff --git a/551/CH5/EX5.50/50.sce b/551/CH5/EX5.50/50.sce new file mode 100755 index 000000000..24ba8cb3c --- /dev/null +++ b/551/CH5/EX5.50/50.sce @@ -0,0 +1,42 @@ +clc
+cp=2.093; //kJ/kg0C
+c=4.187;
+Lf=333.33; //kJ/kg
+m=1; //kg
+T0=273; //K
+T1=268; //K
+T2=298; //K
+Q_s=m*cp*(T0-T1);
+Q_f=m*Lf;
+Q_l=m*c*(T2-T0);
+Q=Q_s+Q_f+Q_l;
+
+disp("(i) Entropy increase of the universe")
+ds_atm=-Q/T2;
+ds_sys1=m*cp*log(T0/T1);
+ds_sys2=Lf/T0;
+ds_sys3=m*c*log(T2/T0);
+ds_total=ds_sys1+ds_sys2+ds_sys3;
+ds_universe=ds_total+ds_atm;
+
+disp("Entropy increase of universe=")
+disp(ds_universe)
+disp("kJ/K")
+
+
+disp("(ii) Minimum amount of work necessary to convert the water back into ice at – 5°C, Wmin.")
+dS_refrigerator=0;
+
+// dS_atm=(Q+W)/T;
+// dS_universe >= 0
+// dS_system=(s1-s4)
+//dS_universe=dS_system+dS_refrigerator+dS_atm
+
+dS_system=-1.6263; //kJ/kg K
+T=298; //K
+
+//For minimum work
+W_min=T*(-dS_system)-Q;
+disp("Minimum work done =")
+disp(W_min)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.6/6.sce b/551/CH5/EX5.6/6.sce new file mode 100755 index 000000000..d5af0af79 --- /dev/null +++ b/551/CH5/EX5.6/6.sce @@ -0,0 +1,7 @@ +clc
+T1=2373; //K
+T2=288; //K
+n_max=1-T2/T1;
+disp("Highest possible theoritical efficiency=")
+disp(n_max*100)
+disp("%")
\ No newline at end of file diff --git a/551/CH5/EX5.7/7.sce b/551/CH5/EX5.7/7.sce new file mode 100755 index 000000000..c546f811e --- /dev/null +++ b/551/CH5/EX5.7/7.sce @@ -0,0 +1,23 @@ +clc
+T1=523; //K
+T2=258; //K
+Q1=90; //kJ
+
+n=1-T2/T1;
+disp("(i) Efficiency of the system")
+disp(n*100)
+disp("%")
+
+
+disp("(ii) The net work transfer")
+W=n*Q1;
+disp("W=")
+disp(W)
+disp("kJ")
+
+
+disp("(iii) Heat rejected to the sink")
+Q2=Q1-W;
+disp("Q2=")
+disp(Q2)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH5/EX5.8/8.sce b/551/CH5/EX5.8/8.sce new file mode 100755 index 000000000..0e3710adf --- /dev/null +++ b/551/CH5/EX5.8/8.sce @@ -0,0 +1,14 @@ +clc
+T1=1023; //K
+T2=298; //K
+n_carnot=1-T2/T1;
+W=75*1000*60*60;
+Q=3.9*74500*1000;
+n_thermal=W/Q;
+disp("n_carnot =")
+disp(n_carnot)
+
+disp("n_thermal =")
+disp(n_thermal)
+
+disp("Since ηthermal > ηcarnot, therefore claim of the inventor is not valid (or possible")
\ No newline at end of file diff --git a/551/CH5/EX5.9/9.sce b/551/CH5/EX5.9/9.sce new file mode 100755 index 000000000..b9ecf0245 --- /dev/null +++ b/551/CH5/EX5.9/9.sce @@ -0,0 +1,10 @@ +clc
+T1=1273; //K
+T2=313; //K
+n_max=1-T2/T1;
+Wnet=1;
+Q1=Wnet/n_max;
+Q2=Q1-Wnet;
+disp("the least rate of heat rejection = ")
+disp(Q2)
+disp("kW")
\ No newline at end of file diff --git a/551/CH6/EX6.1/1.sce b/551/CH6/EX6.1/1.sce new file mode 100755 index 000000000..38b4842b0 --- /dev/null +++ b/551/CH6/EX6.1/1.sce @@ -0,0 +1,18 @@ +clc
+T0=293; //K
+T1=300; //K
+T2=370; //K
+cv=0.716;
+cp=1.005;
+R=0.287;
+p1=1; //bar
+p2=6.8; //bar
+m=1; //kg
+Wmax=-[cv*(T2-T1) - T0*[cp*log(T2/T1)-R*log(p2/p1)]];
+n=1/(1-(log(T2/T1)/log(p2/p1)));
+Wact=m*R*(T1-T2)/(n-1);
+
+I=Wmax - Wact;
+disp("Irreversibility = ")
+disp(I)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH6/EX6.10/10.sce b/551/CH6/EX6.10/10.sce new file mode 100755 index 000000000..a3628ee11 --- /dev/null +++ b/551/CH6/EX6.10/10.sce @@ -0,0 +1,29 @@ +clc
+m_O2=1; //kg
+m_H2=1; //kg
+p=1*10^5; //Pa
+T_O2=450; //K
+T_H2=450; //K
+T0=290; //K
+R0=8.314;
+M_O2=32;
+M_H2=2;
+
+R_O2=R0/M_O2;
+v_O2=m_O2*R_O2*T_O2/p;
+
+R_H2=R0/M_H2;
+v_H2=m_H2*R_H2*T_H2/p;
+
+v_f=v_O2 + v_H2; //total volume after mixing
+
+dS_O2=R_O2*log(v_f/v_O2);
+dS_H2=R_H2*log(v_f/v_H2);
+
+dS_net=dS_O2 + dS_H2;
+
+//Let E be the loss in availability
+E=T0*dS_net;
+disp("Loss in availability=")
+disp(E)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.11/11.sce b/551/CH6/EX6.11/11.sce new file mode 100755 index 000000000..b71adc91b --- /dev/null +++ b/551/CH6/EX6.11/11.sce @@ -0,0 +1,26 @@ +clc
+T0=283; //K
+cp=4.18; //kJ/kgK
+m1=20; //kg
+T1=363; //K
+m2=30; //kg
+T2=303; //K
+T3=327; //K
+
+AE1=integrate('m1*cp*(1-T0/T)', 'T', T0, T1);
+AE2=integrate('m2*cp*(1-T0/T)', 'T', T0, T2);
+
+AE_total=AE1 + AE2; //before mixing
+
+//If T K is the final temperature after mixing
+T=(m1*T1+m2*T2)/(m1+m2);
+m_total=m1+m2;
+
+//Available energy of 50kg of water at 54 0C
+AE3=m_total*cp*[(T3-T0) - T0*log(T3/T0)];
+
+//Decrease in available energy due to mixing dAE
+dAE=AE_total - AE3;
+disp("dAE=")
+disp(dAE)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.12/12.sce b/551/CH6/EX6.12/12.sce new file mode 100755 index 000000000..c5b047d6f --- /dev/null +++ b/551/CH6/EX6.12/12.sce @@ -0,0 +1,25 @@ +clc
+T_w1=323; //K
+T_w2=343; //K
+T_o1=513; //K
+T_o2=363; //K
+SG_oil=0.82;
+c_po=2.6; //kJ/kg K
+c_pw=4.18; //kJ/kg K
+T0=300; //K
+m_o=1; //kg
+
+//Heat lost by oil=Heat gained by water
+m_w=(m_o*c_po*(T_o1-T_o2))/(c_pw*(T_w2-T_w1));
+
+dS_w=m_w*c_pw*log(T_w2/T_w1);
+dS_o=m_o*c_po*log(T_o2/T_o1);
+
+dAE_w=m_w*[c_pw*(T_w2-T_w1)]-T0*dS_w;
+dAE_o=m_o*[c_po*(T_o2-T_o1)]-T0*dS_o;
+
+// Loss in availability E=
+E=dAE_w+dAE_o;
+disp("Loss in availability =")
+disp(E)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.13/13.sce b/551/CH6/EX6.13/13.sce new file mode 100755 index 000000000..53563554f --- /dev/null +++ b/551/CH6/EX6.13/13.sce @@ -0,0 +1,24 @@ +clc
+m_i=1; //kg
+T_i=273; //K
+m_w=12; //kg
+T_w=300; //K
+T0=288; //K
+c_pw=4.18; //kJ/kg K
+c_pi=2.1; //kJ/kg K
+L_i=333.5; //kJ/kg
+
+Tc=(m_w*c_pw*T_w + m_i*c_pw*T_i - L_i)/(m_w*c_pw + m_i*c_pw);
+
+dS_w=m_w*c_pw*log(Tc/T_w);
+dS_i=m_i*c_pw*log(Tc/T_i) + L_i/T_i;
+
+dS_net=dS_w+dS_i;
+disp("Increase in entropy =")
+disp(dS_net)
+disp("kJ/K")
+
+dAE=T0*dS_net;
+disp("Increase in unavailable energy = ")
+disp(dAE)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.14/14.sce b/551/CH6/EX6.14/14.sce new file mode 100755 index 000000000..e2a6bae2f --- /dev/null +++ b/551/CH6/EX6.14/14.sce @@ -0,0 +1,16 @@ +clc
+T1=673; //K
+T2=473; //K
+T0=303; //K
+T1a=T2;
+
+//dSa/dS=T1/T1a
+
+// W=(T1-T0)*dS; Work done by the power cycle when there was no temperature difference between the vapour condensing and vapour evaporating
+// Wa=(T1-T0)*dSa; Work done by the power cycle when the vapour condenses at 400°C and vapour evaporates at 200°C
+
+//Fraction of energy that becomes unavailable is given by (W-Wa)/W
+
+UAE=T0*(T1-T1a)/T1a/(T1-T0);
+disp("the fraction of energy that becomes unavailable =")
+disp(UAE)
\ No newline at end of file diff --git a/551/CH6/EX6.15/15.sce b/551/CH6/EX6.15/15.sce new file mode 100755 index 000000000..917abae97 --- /dev/null +++ b/551/CH6/EX6.15/15.sce @@ -0,0 +1,18 @@ +clc
+T1=293; //K
+T2=353; //K
+Tf=1773; //K
+T0=288; //K
+c_pl=6.3; //kJ/kg K
+
+dAE=c_pl*(T2-T1) - T0*c_pl*log(T2/T1);
+
+n=(1-T0/Tf); //efficiency
+
+//W=heat supplied*efficiency
+//The possible work from a heat engine is a measure of the loss of availability, E
+E=c_pl*(T2-T1)*n;
+
+Effectiveness=dAE/E;
+disp("Effectiveness of the heating process =")
+disp(Effectiveness)
diff --git a/551/CH6/EX6.16/16.sce b/551/CH6/EX6.16/16.sce new file mode 100755 index 000000000..e9626fd2d --- /dev/null +++ b/551/CH6/EX6.16/16.sce @@ -0,0 +1,24 @@ +clc
+T0=293; //K
+T1=293; //K
+T2=373; //K
+T3=323; //K
+cp=1.005;
+
+disp("(i) The ratio of mass flow")
+//cp=Specific heat of air constant pressure
+//cp*T1 + x*cp*T2 = (1+x)*cp*T3
+x=(T3-T1)/(T2-T3);
+disp("x=")
+disp(x)
+
+
+disp("(ii) The effectiveness of heating process")
+ds_13=cp*log(T3/T1);
+ds_32=cp*log(T2/T3);
+A=cp*(T3-T1) - T1*ds_13; //Increase of availability of system
+B=x*[cp*(T2-T3)-T0*(ds_32)];// Loss of availability of surroundings
+
+Effectiveness=A/B;
+disp("Effectiveness of heating process=")
+disp(Effectiveness)
\ No newline at end of file diff --git a/551/CH6/EX6.17/17.sce b/551/CH6/EX6.17/17.sce new file mode 100755 index 000000000..320bcdb4c --- /dev/null +++ b/551/CH6/EX6.17/17.sce @@ -0,0 +1,37 @@ +clc
+m=2.5; //kg
+p1=6*10^5; //Pa
+r=2; //r=V2/V1
+cv=0.718; //kJ/kg K
+R=0.287; //kJ/kg K
+T1=363; //K
+p2=1*10^5; //Pa
+T2=278; //K
+V1=m*R*T1/p1;
+V2=2*V1;
+T0=278; //K
+p0=1*10^5; //Pa
+Q=0; //adiabatic process
+
+disp("(i)The maximum work")
+dS=m*cv*log(T2/T1) + m*R*log(V2/V1);
+Wmax=m*[cv*(T1-T2)] + T0*(cv*log(T2/T1) + R*log(V2/V1));
+disp("Wmax=")
+disp(Wmax)
+disp("kJ")
+
+
+disp("(ii)The change in availability")
+dA=Wmax+p0*(V1-V2);
+disp("Change in availability =")
+disp(dA)
+disp("kJ")
+
+
+disp("(iii) The irreversibility")
+
+I=T0*m*(cv*log(T2/T1)+R*log(V2/V1));
+
+disp("Irreversibility =")
+disp(I)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.18/18.sce b/551/CH6/EX6.18/18.sce new file mode 100755 index 000000000..ab6588cc9 --- /dev/null +++ b/551/CH6/EX6.18/18.sce @@ -0,0 +1,30 @@ +clc
+m=1; //kg
+p1=7*10^5; //Pa
+T1=873; //K
+p2=1*10^5; //Pa
+T2=523; //K
+T0=288; //K
+Q=-9; //kJ/kg
+cp=1.005; //kJ/kg K
+R=0.287; //kJ/kg K
+disp("(i) The decrease in availability ")
+dA=cp*(T1-T2) - T0*(R*log(p2/p1) - cp*log(T2/T1));
+disp("dA=")
+disp(dA)
+disp("kJ/kg")
+
+
+disp("(ii) The maximum work")
+Wmax=dA; //change in availability
+disp("Wmax")
+disp(Wmax)
+disp("kJ/kg")
+
+
+disp("The irreversibility")
+W=cp*(T1-T2) + Q;
+I=Wmax - W;
+disp("Irreversibility =")
+disp(I)
+disp("kJ/kg")
diff --git a/551/CH6/EX6.19/19.sce b/551/CH6/EX6.19/19.sce new file mode 100755 index 000000000..7853806aa --- /dev/null +++ b/551/CH6/EX6.19/19.sce @@ -0,0 +1,29 @@ +clc
+cp=1.005; //kJ/kg K
+cv=0.718; //kJ/kg K
+R=0.287; //kJ/kg K
+m=1; //kg
+T1=290; //K
+T0=290; //K
+T2=400; //K
+p1=1; //bar
+p0=1; //bar
+p2=6; //bar
+
+
+//Wrev=change in internal energy - T0*change in entropy
+disp("(i) The irreversibility")
+Wrev=-[cv*(T2-T1) - T0*[cp*log(T2/T1) - R*log(p2/p1)]];
+n=[1/(1-log(T2/T1)/log(p2/p1))];
+Wact=m*R*(T1-T2)/(n-1);
+
+I=Wrev-Wact;
+disp("Irreversibility=")
+disp(I)
+disp("kJ")
+
+
+disp("(ii)The effectiveness = ")
+effectiveness=Wrev/Wact*100;
+disp(effectiveness)
+disp("%")
\ No newline at end of file diff --git a/551/CH6/EX6.2/2.sce b/551/CH6/EX6.2/2.sce new file mode 100755 index 000000000..10291d25d --- /dev/null +++ b/551/CH6/EX6.2/2.sce @@ -0,0 +1,22 @@ +clc
+T1=1000; //K
+T2=500; //K
+T0=300; //K
+Q=7200; //kJ/min
+
+disp("(i) Net change of entropy :")
+dS_source=-Q/T1;
+dS_system=Q/T2;
+dS_net=dS_source+dS_system;
+disp("dS_net=")
+disp(dS_net)
+disp("kJ/min.K")
+
+
+disp("(ii) Decrease in available energy :")
+AE_source=(T1-T0)*(-dS_source); //Available energy with the source
+AE_system=(T2-T0)*dS_system; //Available energy with the system
+dAE=AE_source - AE_system; //Decrease in available energy
+disp("dAE=")
+disp(dAE)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.20/20.sce b/551/CH6/EX6.20/20.sce new file mode 100755 index 000000000..2bf58487c --- /dev/null +++ b/551/CH6/EX6.20/20.sce @@ -0,0 +1,41 @@ +clc
+I=0.62; //kg/m^2
+N1=2500; //rpm
+w1=2*%pi*N1/60; //rad/s
+m=1.9; //kg; Water equivalent of shaft bearings
+cp=4.18;
+T0=293; //K
+t0=20; //0C
+
+disp("(i)Rise in temperature of bearings")
+KE=1/2*I*w1^2/1000; //kJ
+dT=KE/(m*cp); //rise in temperature of bearings
+disp("dT=")
+disp(dT)
+disp("0C")
+
+t2=t0+dT;
+disp("Final temperature of the bearings =")
+disp(t2)
+disp("0C")
+
+T2=t2+273;
+
+disp("(ii)Final r.p.m. of the flywheel")
+AE=integrate('m*cp*(1-T0/T)', 'T', T0, T2);
+UE=KE - AE;
+
+disp("Available energy =")
+disp(AE)
+disp("kJ")
+
+UAE=KE-AE;
+disp("Unavailable energy =")
+disp(UAE)
+disp("kJ")
+
+w2=sqrt(AE*10^3*2/I);
+N2=w2*60/2/%pi;
+disp("Final rpm of the flywheel =")
+disp(N2)
+disp("rpm")
\ No newline at end of file diff --git a/551/CH6/EX6.21/21.sce b/551/CH6/EX6.21/21.sce new file mode 100755 index 000000000..e67c8626d --- /dev/null +++ b/551/CH6/EX6.21/21.sce @@ -0,0 +1,37 @@ +clc
+p1=8; //bar
+T1=453; //K
+p2=1.4; //bar
+T2=293; //K
+T0=T2;
+p0=1; //bar
+m=1; //kg
+C1=80; //m/s
+C2=40; //m/s
+cp=1.005; //kJ/kg K
+R=0.287; //kJ/kg K
+disp("(i) Reversible work and actual work ")
+A1=cp*(T1-T0)-T0*(cp*log(T1/T0)-R*log(p1/p0))+C1^2/2/10^3; //Availability at the inlet
+A2=cp*(T2-T0)-T0*(cp*log(T2/T0)-R*log(p2/p0))+C2^2/2/10^3; //Availability at the exit
+
+W_rev=A1-A2;
+disp("W_rev =")
+disp(W_rev)
+disp("kJ/kg")
+
+W_act=cp*(T1-T2) + (C1^2-C2^2)/2/10^3;
+disp("W_act =")
+disp(W_act)
+disp("kJ/kg")
+
+disp("(ii) Irreversibilty and effectiveness =")
+
+I=W_rev-W_act;
+disp("Irreversibilty =")
+disp(I)
+disp("kJ/kg")
+
+Effectiveness=W_act/W_rev*100;
+disp("Effectiveness =")
+disp(Effectiveness)
+disp("%")
\ No newline at end of file diff --git a/551/CH6/EX6.22/22.sce b/551/CH6/EX6.22/22.sce new file mode 100755 index 000000000..d4bafff0d --- /dev/null +++ b/551/CH6/EX6.22/22.sce @@ -0,0 +1,38 @@ +clc
+p1=20; //bar
+t1=400; //0C
+p2=4; //bar
+t2=250; //0C
+t0=20; //0C
+T0=t0+273;
+h1=3247.6; //kJ/kg
+s1=7.127; //kJ/kg K
+
+//let h2'=h2a and s2'=s2a
+h2a=2964.3; //kJ/kg
+s2a=7.379; //kJ/kg K
+
+s2=s1;
+s1a=s1;
+
+//By interpolation, we get
+h2=2840.8; //kJ/kg
+
+
+disp("(i) Isentropic efficiency")
+n_isen=(h1-h2a)/(h1-h2);
+disp(" Isentropic efficiency =")
+disp(n_isen)
+
+
+disp("(ii) Loss of availability")
+A=h1-h2a + T0*(s2a-s1a);
+disp(" Loss of availability=")
+disp(A)
+disp("kJ/kg")
+
+
+disp("(iii)Effectiveness")
+Effectiveness=(h1-h2a)/A;
+disp("Effectiveness =")
+disp(Effectiveness)
\ No newline at end of file diff --git a/551/CH6/EX6.3/3.sce b/551/CH6/EX6.3/3.sce new file mode 100755 index 000000000..07181e31f --- /dev/null +++ b/551/CH6/EX6.3/3.sce @@ -0,0 +1,39 @@ +clc
+m=8; //kg
+T1=650; //K
+p1=5.5*10^5; //Pa
+p0=1*10^5; //Pa
+T0=300; //K
+cp=1.005; //kJ/kg.K
+cv=0.718;
+R=0.287;
+//p1*v1/T1=p0*v0/T0
+//Let r=v1/v0=1/2.54
+r=1/2.54;
+
+
+disp("(i) Change in available energy(for bringing the system to dead state)=")
+ds=cv*log(T1/T0) + R*log(r);
+dAE=m*[cv*(T1-T0) - T0*[ds]];
+//dAE is the change in available energy in kJ
+
+V1=m*R*10^3*T1/p1;
+V0=V1/r;
+disp("Loss of availability, L=")
+L=p0*(V0 - V1)/10^3;
+disp(L)
+disp("kJ")
+
+
+disp("(ii) Available Energy and Effectiveness")
+Q=m*cp*(T1-T0);
+ds=m*cp*log(T1/T0);
+Unavailable_energy=T0*ds;
+Available_energy = Q - Unavailable_energy;
+disp("Available energy = ")
+disp(Available_energy)
+disp("kJ")
+
+Effectiveness=Available_energy/dAE;
+disp("Effectiveness = ")
+disp(Effectiveness)
diff --git a/551/CH6/EX6.4/4.sce b/551/CH6/EX6.4/4.sce new file mode 100755 index 000000000..5e5a21224 --- /dev/null +++ b/551/CH6/EX6.4/4.sce @@ -0,0 +1,23 @@ +clc
+c_pg=1; //kJ/kgK
+h_fg=1940.7; //kJ/kg
+Ts=473; //K ; Temperature of saturation of steam
+T1=1273; //K ; Initial temperature of gases
+T2=773; //K ; Final temperature of gases
+T0=293; //K ; atmospheric temperature
+
+//Heat lost by gases=Heat gained by 1 kg saturated water when it is converted to steam at 200 0C
+
+m_g=h_fg/c_pg/(T1-T2);
+dS_g=m_g*c_pg*log(T2/T1);
+dS_w=h_fg/Ts;
+
+dS_net=dS_g + dS_w;
+disp("Net change in entropy = ")
+disp(dS_net)
+disp("kJ/K")
+
+E=T0*dS_net; //Increase in unavailable energy due to hea transfer
+disp("Increase in unavailable energy =")
+disp(E)
+disp("kJ")
diff --git a/551/CH6/EX6.5/5.sce b/551/CH6/EX6.5/5.sce new file mode 100755 index 000000000..27fff3edd --- /dev/null +++ b/551/CH6/EX6.5/5.sce @@ -0,0 +1,21 @@ +clc
+m_g=3; //kg
+p1=2.5; //bar
+T1=1200; //K; Temperature of infinite source
+T1a=400; //K; Initial temperature
+Q=600; //kJ
+cv=0.81; //kJ/kg.K
+T0=290; //K; Surrounding Temperature
+//final temperature = T2a
+
+T2a=Q/m_g/cv + T1a;
+AE=(T1-T0)*Q/T1; //Available energy with the source
+dS=m_g*cv*log(T2a/T1a); //Change in entropy of the gas
+
+UAE=T0*dS; //Unavailability of the gas
+A=Q-UAE; //Available energy with the gas
+
+loss=AE-A;
+disp("Loss in available energy due to heat transfer =")
+disp(loss)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.6/6.sce b/551/CH6/EX6.6/6.sce new file mode 100755 index 000000000..58e4bf7a7 --- /dev/null +++ b/551/CH6/EX6.6/6.sce @@ -0,0 +1,17 @@ +clc
+m=60; //kg
+T1=333; //K
+T0=279; //K
+p=1; //atm
+cp=4.187;
+
+//dW=-m*cp*(1-T0/T)dT
+//Wmax=Available energy
+Wmax=integrate('m*cp*(1-T0/T)', 'T', T0, T1);
+Q1=m*cp*(T1-T0);
+
+//Let unavailable energy=E
+E=Q1-Wmax;
+disp("unavailable energy = ")
+disp(E)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.7/7.sce b/551/CH6/EX6.7/7.sce new file mode 100755 index 000000000..c4952d0b3 --- /dev/null +++ b/551/CH6/EX6.7/7.sce @@ -0,0 +1,13 @@ +clc
+m=15; //kg
+T1=340; //K
+T0=300; //K
+cp=4.187; //kJ/kgK
+//Work added during churning = Increase in enthalpy of water
+W=m*cp*(T1-T0);
+ds=cp*log(T1/T0);
+AE=m*[cp*(T1-T0)-T0*ds];
+AE_loss=W-AE; //Loss in availability
+disp("Loss in availability")
+disp(AE_loss)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH6/EX6.8/8.sce b/551/CH6/EX6.8/8.sce new file mode 100755 index 000000000..69cefbca9 --- /dev/null +++ b/551/CH6/EX6.8/8.sce @@ -0,0 +1,32 @@ +clc
+m=5; //kg
+T1=550; //K
+p1=4*10^5; //Pa
+T2=290; //K
+T0=T2;
+p2=1*10^5; //Pa
+p0=p2;
+cp=1.005; //kJ/kg K
+cv=0.718; //kJ/kg K
+R=0.287; //kJ/kg K
+
+disp("(i) Availability of the system :")
+ds=cp*log(T1/T0) - R*log(p1/p0);
+Availability=m*[cv*(T1-T0) - T0*ds];
+disp("Availability of the system =")
+disp(Availability)
+disp("kJ")
+
+
+disp("(ii) Available energy and Effectiveness")
+Q=m*cp*(T1-T0);
+dS=m*cp*log(T1/T0);
+E=T0*dS; //Unavailable energy
+AE=Q-E;
+disp("Available Energy = ")
+disp(AE)
+disp("kJ")
+
+disp("Effectiveness=")
+Effectiveness=AE/Availability;
+disp(Effectiveness)
diff --git a/551/CH6/EX6.9/9.sce b/551/CH6/EX6.9/9.sce new file mode 100755 index 000000000..db49907de --- /dev/null +++ b/551/CH6/EX6.9/9.sce @@ -0,0 +1,24 @@ +clc
+R=0.287; //kJ/kgK
+cp=1.005; //kJ/kgK
+m=25/60; //kg/s
+p1=1; //bar
+p2=2; //bar
+T1=288; //K
+T0=T1;
+T2=373; //K
+
+W_act=cp*(T2-T1); //W_actual
+W_total= m*W_act;
+
+disp("Total actual power required =")
+disp(W_total)
+disp("kW")
+
+ds=cp*log(T2/T1) - R*log(p2/p1);
+Wmin=cp*(T2-T1) - T0*(ds);
+
+disp("Minimuumm work required = ")
+W=m*Wmin;
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH7/EX7.17/17.sce b/551/CH7/EX7.17/17.sce new file mode 100755 index 000000000..f5e80e1ab --- /dev/null +++ b/551/CH7/EX7.17/17.sce @@ -0,0 +1,31 @@ +clc
+B=5*10^(-5); // /K
+K=8.6*10^(-12); // m^2/N
+v=0.114*10^(-3); //m^3/kg
+p2=800*10^5; //Pa
+p1=20*10^5; //Pa
+T=288; //K
+disp("(i) Work done on the copper = ")
+W=-v*K/2*(p2^2-p1^2);
+disp(W)
+disp("J/kg")
+
+disp("(ii) Change in entropy =")
+ds=-v*B*(p2-p1);
+disp(ds)
+disp("J/kg K")
+
+disp("(iii) The heat transfer =")
+Q=T*ds;
+disp(Q)
+disp("J/kg")
+
+disp("(iv) Change in internal energy =")
+du=Q-W;
+disp(du)
+disp("J/kg")
+
+disp("(v) cp – cv =")
+R=B^2*T*v/K;
+disp(R)
+disp("J/kg K")
\ No newline at end of file diff --git a/551/CH7/EX7.18/18.sce b/551/CH7/EX7.18/18.sce new file mode 100755 index 000000000..b0a666801 --- /dev/null +++ b/551/CH7/EX7.18/18.sce @@ -0,0 +1,10 @@ +clc
+vg=0.1274; //m^3/kg
+vf=0.001157; //m^3/kg
+// dp/dT=32; //kPa/K
+T3=473; //K
+
+h_fg=32*10^3*T3*(vg-vf)/10^3;
+disp("h_fg=")
+disp(h_fg)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH7/EX7.19/19.sce b/551/CH7/EX7.19/19.sce new file mode 100755 index 000000000..341aee2f9 --- /dev/null +++ b/551/CH7/EX7.19/19.sce @@ -0,0 +1,12 @@ +clc
+h_fg=334; //kJ/kg
+v_liq=1; //m^3/kg
+v_ice=1.01; //m^3/kg
+T1=273; //K
+T2=263; //K
+p1=1.013*10^5; //Pa
+
+p2=(p1+h_fg*10^3/(v_ice-v_liq)*log(T1/T2))/10^5;
+disp("p2=")
+disp(p2)
+disp("bar")
\ No newline at end of file diff --git a/551/CH7/EX7.20/20.sce b/551/CH7/EX7.20/20.sce new file mode 100755 index 000000000..d997b33c0 --- /dev/null +++ b/551/CH7/EX7.20/20.sce @@ -0,0 +1,15 @@ +clc
+h_fg=294.54; //kJ/kg
+
+// log(p)=7.0323 - 3276.6/T - 0.652*log(T)
+// Differentiating both sides, we get
+// 1/2.302/p*dp/dT=3276.6/T^2-0.652/2.302/T
+
+//Putting p=0.1 bar , we get
+p=0.1; //bar
+T=523; //K
+
+vg=h_fg*10^3/T/(2.302*3276.6*p*10^5/T^2 - 0.652*p*10^5/T);
+disp("vg=")
+disp(vg)
+disp("m^3/kg")
\ No newline at end of file diff --git a/551/CH8/EX8.1/1.sce b/551/CH8/EX8.1/1.sce new file mode 100755 index 000000000..25dd8df7e --- /dev/null +++ b/551/CH8/EX8.1/1.sce @@ -0,0 +1,22 @@ +clc
+R=287; //J/kg K
+V1=40; //m^3
+V2=40; //m^3
+p1=1*10^5; //Pa
+p2=0.4*10^5; //Pa
+T1=298; //K
+T2=278; //K
+
+m1=p1*V1/R/T1;
+m2=p2*V2/R/T2;
+
+//Let mass of air removed be m
+m=m1-m2;
+disp("Mass of air removed =")
+disp(m)
+disp("kg")
+
+V=m*R*T1/p1;
+disp("Volume of gas removed =")
+disp(V)
+disp("m^3")
\ No newline at end of file diff --git a/551/CH8/EX8.10/10.sce b/551/CH8/EX8.10/10.sce new file mode 100755 index 000000000..269d4b7ce --- /dev/null +++ b/551/CH8/EX8.10/10.sce @@ -0,0 +1,41 @@ +clc
+V=3; //m^3
+m=10; //kg
+T=300; //K
+
+disp("(i) Using perfect gas equation")
+R0=8314;
+M=44;
+R=R0/M;
+p=m*R*T/V;
+disp("Pressure Using perfect gas equation =")
+disp(p)
+disp("N/m^2")
+
+
+disp("(ii) Using Van der Waals’ equation")
+a=362850; //Nm^4/(kg-mol)^2
+b=0.0423; //m^3/(kg-mol)
+v=13.2; //m^3/kg-mol
+
+p=R0*T/(v-b) - a/v^2;
+disp("Pressure Using Van der Waals’ equation=")
+disp(p)
+disp("N/m^2")
+
+
+disp("(iii) Using Beattie Bridgeman equation")
+
+A0=507.2836;
+a=0.07132;
+B0=0.10476;
+b=0.07235;
+C=66*10^4;
+A=A0*(1-a/v);
+B=B0*(1-b/v);
+e=C/v/T^3;
+
+p=R0*T*(1-e)/v^2*(v+B) - A/v^2;
+disp("Pressure Using Beattie Bridgeman equation = ")
+disp(p)
+disp("N/m^2")
diff --git a/551/CH8/EX8.11/11.sce b/551/CH8/EX8.11/11.sce new file mode 100755 index 000000000..98d981172 --- /dev/null +++ b/551/CH8/EX8.11/11.sce @@ -0,0 +1,19 @@ +clc
+a=139250; //Nm^4/(kg-mol)^2
+b=0.0314; //m^3/kg-mol
+R0=8314; //Nm/kg-mol K
+v1=0.2*32; //m^3/kg-mol
+v2=0.08*32; //m^3/kg-mol
+T=333; //K
+disp("(i) Work done during the process")
+W=integrate('R0*T/(v-b) - a/v^2', 'v', v1, v2);
+disp("W=")
+disp(W)
+disp("Nm/kg-mol")
+
+
+disp("(ii) The final pressure")
+p2=R0*T/(v2-b) - a/v2^2;
+disp("p2=")
+disp(p2)
+disp("N/m^2")
\ No newline at end of file diff --git a/551/CH8/EX8.12/12.sce b/551/CH8/EX8.12/12.sce new file mode 100755 index 000000000..3912a41c4 --- /dev/null +++ b/551/CH8/EX8.12/12.sce @@ -0,0 +1,10 @@ +clc
+pr=20;
+Z=1.25;
+Tr=8.0;
+Tc=282.4; //K
+
+T=Tc*Tr;
+disp("Temperature =")
+disp(T)
+disp("K")
diff --git a/551/CH8/EX8.13/13.sce b/551/CH8/EX8.13/13.sce new file mode 100755 index 000000000..a93cb98b8 --- /dev/null +++ b/551/CH8/EX8.13/13.sce @@ -0,0 +1,15 @@ +clc
+p=260*10^5; //Pa
+T=288; //K
+pc=33.94*10^5; //Pa
+Tc=126.2; //K
+R=8314/28;
+
+pr=p/pc;
+Tr=T/Tc;
+Z=1.08;
+
+rho=p/Z/R/T;
+disp("Density of N2=")
+disp(rho)
+disp("kg/m^3")
\ No newline at end of file diff --git a/551/CH8/EX8.14/14.sce b/551/CH8/EX8.14/14.sce new file mode 100755 index 000000000..96f774f90 --- /dev/null +++ b/551/CH8/EX8.14/14.sce @@ -0,0 +1,12 @@ +clc
+p=200*10^5; //Pa
+pc=73.86*10^5; //Pa
+Tc=304.2; //K
+pr=p/pc;
+Z=1;
+Tr=2.48;
+
+T=Tr*Tc;
+disp("Temperature =")
+disp(T)
+disp("K")
\ No newline at end of file diff --git a/551/CH8/EX8.15/15.sce b/551/CH8/EX8.15/15.sce new file mode 100755 index 000000000..13d3ca232 --- /dev/null +++ b/551/CH8/EX8.15/15.sce @@ -0,0 +1,17 @@ +clc
+d=12; //m; diameter of spherical balloon
+V=4/3*%pi*(d/2)^3;
+T=303; //K
+p=1.21*10^5; //Pa
+pc=12.97*10^5; //Pa
+Tc=33.3; //K
+R=8314/2;
+
+pr=p/pc;
+Tr=T/Tc;
+Z=1;
+
+m=p*V/Z/R/T;
+disp("Mass of H2 in the balloon =")
+disp(m)
+disp("kg")
\ No newline at end of file diff --git a/551/CH8/EX8.16/16.sce b/551/CH8/EX8.16/16.sce new file mode 100755 index 000000000..a78659033 --- /dev/null +++ b/551/CH8/EX8.16/16.sce @@ -0,0 +1,23 @@ +clc
+
+// dp_c/dv=0
+// d^2 p/dv^2=0
+
+// p_cp=R0*T_cp/(v_cp-b) - a/v_cp^2
+
+// As T_cp is constant
+// dp_cp/dv_cp=(-R0*T_cp)/(v_cp-b)^2 + 2*a/v_cp^3 = 0
+
+// d^2 p_cp/dv_cp=2*R0*T_cp/(v_cp-b)^3 - 6*a/v_cp^4 = 0
+
+// Solving these we get v_cp=3*b;
+// 2*a/v_cp^3 - R0*T_cp/[v_cp-1/3*v_cp]^2
+
+//a=9/8*R0*T_cp*v_cp
+
+//Z_cp=p_cp*v_cp/R0/T_cp
+
+Z_cp=3/2-9/8;
+
+disp("Z_cp=")
+disp(Z_cp)
\ No newline at end of file diff --git a/551/CH8/EX8.2/2.sce b/551/CH8/EX8.2/2.sce new file mode 100755 index 000000000..c985e62c9 --- /dev/null +++ b/551/CH8/EX8.2/2.sce @@ -0,0 +1,24 @@ +clc
+V=0.04; //m^3
+p=120*10^5; //Pa
+T=293; //K
+R0=8314;
+
+disp("(i) kg of nitrogen the flask can hold")
+M=28; //molecular weight of Nitrogen
+R=R0/M;
+
+m=p*V/R/T;
+disp("kg of nitrogen=")
+disp(m)
+disp("kg")
+
+
+disp("(ii) Temperature at which fusible plug should melt")
+p=150*10^5; //Pa
+
+T=p*V/R/m; //K
+t=T-273; //0C
+disp("Temperature =")
+disp(t)
+disp("°C")
\ No newline at end of file diff --git a/551/CH8/EX8.3/3.sce b/551/CH8/EX8.3/3.sce new file mode 100755 index 000000000..ef7d02356 --- /dev/null +++ b/551/CH8/EX8.3/3.sce @@ -0,0 +1,29 @@ +clc
+p1=1*10^5; //Pa
+T1=293; //K
+d=6; //m; diameter of the spherical balloon
+p2=0.94*p1;
+T2=T1;
+cv=10400; //J/kg K
+R=8314/2;
+r=3; //m
+
+disp("(i) Mass of original gas escaped")
+
+//dm=m1-m2
+//dm=(p1-p2)*V1/R/T1
+//m1=p1*V1/R/T1
+
+%mass_escaped=(p1-p2)/p1*100;
+disp("%mass_escaped =")
+disp(%mass_escaped)
+disp("%")
+
+disp("(ii)Amount of heat to be removed ")
+T2=0.94*T1;
+m=p1*4/3*%pi*r^3/R/T1;
+
+Q=m*cv*(T1-T2)/10^6;
+disp("Q =")
+disp(Q)
+disp("MJ")
\ No newline at end of file diff --git a/551/CH8/EX8.4/4.sce b/551/CH8/EX8.4/4.sce new file mode 100755 index 000000000..44081e543 --- /dev/null +++ b/551/CH8/EX8.4/4.sce @@ -0,0 +1,72 @@ +clc
+m=28; //kg
+V1=3; //m^3
+T1=363; //K
+R0=8314;
+M=28; //Molecular mass of N2
+R=R0/m;
+V2=V1;
+T2=293; //K
+
+disp("(i) Pressure (p1) and specific volume (v1) of the gas")
+
+p1=m*R*T1/V1/10^5; //bar
+disp("Pressure =")
+disp(p1)
+disp("bar")
+
+v1=V1/m;
+disp("specific volume=")
+disp(v1)
+disp("m^3/kg")
+
+
+disp("(ii) cp = ?, cv = ?")
+//cp-cv=R/1000;
+//cp-1.4cv=0;
+//solving the above two eqns
+A=[1,-1;1,-1.4];
+B=[R/1000;0];
+X=inv(A)*B;
+
+cp=X(1,1);
+disp("cp=")
+disp(cp)
+disp("kJ/kg K")
+
+cv=X(2,1);
+disp("cv=")
+disp(cv)
+disp("kJ/kg K")
+
+
+disp("(iii) Final pressure of the gas after cooling to 20°C")
+p2=p1*T2/T1;
+disp("p2=")
+disp(p2)
+disp("bar")
+
+
+disp("(iv) du, dh, s, Q")
+
+du=cv*(T2-T1);
+disp("Increase in specific internal energy=")
+disp(du)
+disp("kJ/kg")
+
+dh=cp*(T2-T1);
+disp("Increase in specific Enthalpy =")
+disp(dh)
+disp("kJ/kg")
+
+v2=v1;
+ds=cv*log(T2/T1) + R*log(v2/v1);
+disp("Increase in specific entropy =")
+disp(ds)
+disp("kJ/kg K")
+
+W=0; //constant volume process
+Q=m*du+W;
+disp("Heat transfer =")
+disp(Q)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH8/EX8.5/5.sce b/551/CH8/EX8.5/5.sce new file mode 100755 index 000000000..6cb762cfd --- /dev/null +++ b/551/CH8/EX8.5/5.sce @@ -0,0 +1,62 @@ +clc
+
+disp("Part (a)")
+
+R=0.287; //kJ/kg K
+y=1.4;
+m1=1; //kg
+p1=8*10^5; //Pa
+T1=373; //K
+p2=1.8*10^5; //Pa
+cv=0.717; //kJ/kg K
+n=1.2;
+//pv^1.2 = constant
+
+disp("(i) The final specific volume, temperature and increase in entropy")
+
+v1=R*10^3*T1/p1;
+v2=v1*(p1/p2)^(1/n);
+disp("v2=")
+disp(v2)
+disp("m^3/kg")
+
+T2=p2*v2/R/10^3; //K
+t2=T2-273; //0C
+disp("Final temperature =")
+disp(t2)
+disp("0C")
+
+ds=cv*log(T2/T1) + R*log(v2/v1);
+disp("ds=")
+disp(ds)
+disp("kJ/kg K")
+
+
+disp("(ii) Work done and heat transfer")
+
+W=R*(T1-T2)/(n-1);
+disp("Work done=")
+disp(W)
+disp("kJ/kg")
+
+Q=cv*(T2-T1) + W;
+disp("Heat transfer=")
+disp(Q)
+disp("kJ/kg")
+
+
+disp("Part (b)")
+
+disp("(i) Though the process is assumed now to be irreversible and adiabatic, the end states are given to be the same as in (a). Therefore, all the properties at the end of the process are the same as in (a).")
+
+
+disp("(ii) Adiabatic process")
+Q=0;
+disp("Heat transfer=")
+disp(Q)
+disp("kJ/kg")
+
+W=-cv*(T2-T1);
+disp("Work done=")
+disp(W)
+disp("kJ/kg")
\ No newline at end of file diff --git a/551/CH8/EX8.6/6.sce b/551/CH8/EX8.6/6.sce new file mode 100755 index 000000000..44ad89359 --- /dev/null +++ b/551/CH8/EX8.6/6.sce @@ -0,0 +1,15 @@ +clc
+d=2.5; //m; diameter
+V1=4/3*%pi*(d/2)^3; //volume of each sphere
+T1=298; //K
+T2=298; //K
+m1=16; //kg
+m2=8; //kg
+V=2*V1; //total volume
+m=m1+m2;
+R=287; //kJ/kg K
+
+p=m*R*T1/V/10^5; //bar
+disp("pressure in the spheres when the system attains equilibrium=")
+disp(p)
+disp("bar")
\ No newline at end of file diff --git a/551/CH8/EX8.7/7.sce b/551/CH8/EX8.7/7.sce new file mode 100755 index 000000000..f7c7e14d0 --- /dev/null +++ b/551/CH8/EX8.7/7.sce @@ -0,0 +1,36 @@ +clc
+m=6.5/60; //kg/s
+cv=0.837; //kJ/kg K
+p1=10*10^5; //Pa
+p2=1.05*10^5; //Pa
+T1=453; //K
+R0=8.314;
+M=44; //Molecular mass of CO2
+
+R=R0/M;
+cp=cv+R;
+y=cp/cv;
+
+T2=T1*(p2/p1)^((y-1)/y);
+t2=T2-273;
+disp("Final temperature=")
+disp(t2)
+disp("0C")
+
+v2=R*10^3*T2/p2; //m^3/kg
+disp("final specific volume =")
+disp(v2)
+disp("m^3/kg")
+
+ds=0; //Reversible and adiabatic process
+disp("Increase in entropy=")
+disp(ds)
+
+Q=0; //Adiabatic process
+disp("Heat transfer rate from turbine=")
+disp(Q)
+
+W=m*cp*(T1-T2);
+disp("Power delivered by the turbine=")
+disp(W)
+disp("kW")
\ No newline at end of file diff --git a/551/CH8/EX8.8/8.sce b/551/CH8/EX8.8/8.sce new file mode 100755 index 000000000..084d7d2c7 --- /dev/null +++ b/551/CH8/EX8.8/8.sce @@ -0,0 +1,47 @@ +clc
+p1=8*10^5; //Pa
+V1=0.035; //m^3
+T1=553; //K
+p2=8*10^5; //Pa
+V2=0.1; //m^3
+n=1.4;
+R=287; //J/kg K
+T3=553; //K
+cv=0.71; //kJ/kg K
+
+m=p1*V1/R/T1;
+T2=p2*V2/m/R;
+p3=p2/((T2/T3)^(n/(n-1)));
+V3=m*R*T3/p3;
+
+disp("(i) The heat received in the cycle")
+
+//constant pressure process 1-2
+W_12=p1*(V2-V1)/10^3; //kJ
+Q_12=m*cv*(T2-T1) + W_12; //kJ
+
+//polytropic process 2-3
+W_23=m*R/10^3*(T2-T3)/(n-1);
+Q_23=m*cv*(T3-T2) + W_23;
+
+Q_received=Q_12 + Q_23;
+disp("Total heat received in the cycle=")
+disp(Q_received)
+disp("kJ")
+
+
+disp("(ii) The heat rejected in the cycle")
+
+//Isothermal process 3-1
+W_31=p3*V3*log(V1/V3)/10^3; //kJ
+Q_31=m*cv*(T3-T1) + W_31;
+disp("Heat rejected in the cycle =")
+disp(-Q_31)
+disp("kJ")
+
+
+disp("(ii) Efficiency of the cycle")
+n=(Q_received - (-Q_31))/Q_received*100;
+disp("Efficiency of the cycle =")
+disp(n)
+disp("%")
\ No newline at end of file diff --git a/551/CH8/EX8.9/9.sce b/551/CH8/EX8.9/9.sce new file mode 100755 index 000000000..e5f552d0b --- /dev/null +++ b/551/CH8/EX8.9/9.sce @@ -0,0 +1,22 @@ +clc
+v=44; //m^3/kg-mol
+T=373; //K
+
+disp("(i) Using Van der Waals’ equation")
+
+a=362850; //N*m^4/(kg-mol)^2
+b=0.0423; //M^3/kg-mol
+R0=8314; //J/kg K
+
+p=((R0*T/(v-b)) - a/v^2);
+disp("Pressure using Van der Waals equation=")
+disp(p)
+disp("N/m^2")
+
+
+disp("(ii) Using perfect gas equation")
+
+p=R0*T/v;
+disp("Pressure using perfect gas equation=")
+disp(p)
+disp("N/m^2")
\ No newline at end of file diff --git a/551/CH9/EX9.1/1.sce b/551/CH9/EX9.1/1.sce new file mode 100755 index 000000000..3845860c4 --- /dev/null +++ b/551/CH9/EX9.1/1.sce @@ -0,0 +1,35 @@ +clc
+V=0.35; //m^3
+m_CO=0.4; //kg
+m_air=1; //kg
+m_O2=0.233; //kg
+m_N2=0.767; //kg
+T=293; //K
+R0=8.314; //kJ/kg K
+M_O2=32; //Molecular mass of O2
+M_N2=28; //Molecular mass of N2
+M_CO=28; //Molecular mass of CO
+
+disp("Partial Pressures=")
+
+p_O2=m_O2*R0*10^3*T/M_O2/V/10^5; //bar
+disp("partial pressure for p_O2")
+disp(p_O2)
+disp("bar")
+
+p_N2=m_N2*R0*10^3*T/M_N2/V/10^5; //bar
+disp("partial pressure for p_N2")
+disp(p_N2)
+disp("bar")
+
+p_CO=m_CO*R0*10^3*T/M_CO/V/10^5; //bar
+disp("partial pressure for p_CO")
+disp(p_CO)
+disp("bar")
+
+
+disp("(ii) Total pressure in the vessel")
+p=p_O2+p_N2+p_CO;
+disp("p=")
+disp(p)
+disp("bar")
\ No newline at end of file diff --git a/551/CH9/EX9.10/10.sce b/551/CH9/EX9.10/10.sce new file mode 100755 index 000000000..b1d914abf --- /dev/null +++ b/551/CH9/EX9.10/10.sce @@ -0,0 +1,120 @@ +clc
+p=4*10^5; //Pa
+T=293; //K
+R0=8.314;
+
+m_N2=4; //kg
+m_CO2=6; //kg
+
+M_N2=28; //Molecular mass
+M_CO2=44; //Molecular mass
+
+n_N2=m_N2/M_N2; //moles of N2
+n_CO2=m_CO2/M_CO2; //moles of CO2
+
+x_N2=n_N2/(n_N2+n_CO2);
+disp("x_N2=")
+disp(x_N2)
+
+x_CO2=n_CO2/(n_CO2+n_N2);
+disp("x_CO2=")
+disp(x_CO2)
+
+
+disp("(ii) The equivalent molecular weight of the mixture")
+M=x_N2*M_N2 + x_CO2*M_CO2;
+disp("M=")
+disp(M)
+disp("kg/kg-mole")
+
+
+disp("(iii) The equivalent gas constant of the mixture")
+m=m_N2+m_CO2;
+Rmix=(m_N2*(R0/M_N2) + m_CO2*(R0/M_CO2))/m;
+disp("Rmix=")
+disp(Rmix)
+disp("kJ/kg K")
+
+
+disp("(iv) The partial pressures and partial volumes")
+P_N2=x_N2*p/10^5;
+disp("P_N2=")
+disp(P_N2)
+disp("bar")
+
+P_CO2=x_CO2*p/10^5;
+disp("P_CO2=")
+disp(P_CO2)
+disp("bar")
+
+V_N2=m_N2*R0/M_N2*T/p*10^3;
+disp("V_N2")
+disp(V_N2)
+disp("m^3")
+
+V_CO2=m_CO2*R0/M_CO2*T/p*10^3;
+disp("V_CO2")
+disp(V_CO2)
+disp("m^3")
+
+disp("(v) The volume and density of the mixture")
+
+V=m*Rmix*10^3*T/p;
+disp("V=")
+disp(V)
+disp("m^3")
+
+rho_mix=m/V;
+disp("Density of mixture=")
+disp(rho_mix)
+disp("kg/m^3")
+
+
+disp("(vi) cp and cv of the mixture")
+
+y_N2=1.4;
+cv_N2=(R0/M_N2)/(y_N2 - 1);
+cp_N2=cv_N2*y_N2;
+
+y_CO2=1.286;
+cv_CO2=(R0/M_CO2)/(y_CO2 - 1);
+cp_CO2=cv_CO2*y_CO2;
+
+cp=(m_N2*cp_N2 + m_CO2*cp_CO2)/(m_N2+m_CO2);
+disp("cp=")
+disp(cp)
+disp("kJ/kg K")
+
+cv=(m_N2*cv_N2 + m_CO2*cv_CO2)/(m_N2+m_CO2);
+disp("cv=")
+disp(cv)
+disp("kJ/kg K")
+
+
+
+T1=293; //K
+T2=323; //K
+dU=m*cv*(T2-T1);
+disp("Change in internal energy =")
+disp(dU)
+disp("kJ")
+
+dH=m*cp*(T2-T1);
+disp("Change in enthalpy =")
+disp(dH)
+disp("kJ")
+
+dS=m*cv*log(T2/T1); //Constant volume process
+disp("Change in entropy=")
+disp(dS)
+disp("kJ/kg K")
+
+
+disp("When the mixture is heated at constant pressure")
+
+disp("If the mixture is heated at constant pressure ΔU and ΔH will remain the same")
+
+dS=m*cp*log(T2/T1);
+disp("Change in entropy =")
+disp(dS)
+disp("kJ/kg K")
\ No newline at end of file diff --git a/551/CH9/EX9.11/11.sce b/551/CH9/EX9.11/11.sce new file mode 100755 index 000000000..4e7fac62d --- /dev/null +++ b/551/CH9/EX9.11/11.sce @@ -0,0 +1,59 @@ +clc
+
+Cv_O2=21.07; //kJ/mole K
+Cv_CO=20.86; //kJ/mole K
+
+p_O2=8*10^5; //Pa
+p_CO=1*10^5; //Pa
+
+V_O2=1.8; //m^3
+V_CO=3.6; //m^3
+
+T_O2=323; //K
+T_CO=293; //K
+
+R0=8314;
+
+n_O2=p_O2*V_O2/R0/T_O2;
+n_CO=p_CO*V_CO/R0/T_CO;
+
+n=(n_O2+n_CO);
+V=(V_O2+V_CO);
+
+disp("(i) Final temperature (T) and pressure (p) of the mixture")
+
+//Before mixing
+U1=n_O2*Cv_O2*T_O2 + n_CO*Cv_CO*T_CO;
+
+//After mixing
+//U2=T*(n_O2*Cv_O2 + n_CO*Cv_CO);
+//U1=U2
+
+T=U1/(n_O2*Cv_O2 + n_CO*Cv_CO);
+t=T-273;
+disp("Final temperature =")
+disp(t)
+disp("°C")
+
+p=n*R0*T/V/10^5;
+disp("Final pressure =")
+disp(p)
+disp("bar")
+
+
+disp("(ii) Change of entropy")
+//For oxygen
+dS_O1A=n_O2*R0*log(V/V_O2); //isothermal process
+dS_O2A=n_O2*Cv_O2*log(T_O2/T); //constant volume process
+
+dS_O12=dS_O1A - dS_O2A; // Change of entropy of O2
+
+//For CO
+
+dS_CO12=n_CO*R0*log(V/V_CO) + n_CO*Cv_CO*log(T/T_CO); //Change of entropy of CO
+
+
+dS=(dS_O12 + dS_CO12)/10^3;
+disp("Change of entropy of system =")
+disp(dS)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH9/EX9.12/12.sce b/551/CH9/EX9.12/12.sce new file mode 100755 index 000000000..02d2034fc --- /dev/null +++ b/551/CH9/EX9.12/12.sce @@ -0,0 +1,63 @@ +clc
+
+p_A=16*10^5; //Pa
+p_B=6.4*10^5; //Pa
+
+T_A=328; //K
+T_B=298; //K
+
+n_A=0.6; //kg-mole
+m_B=3; //kg
+
+R0=8314;
+M_A=28;
+y=1.4;
+
+V_A=n_A*R0*T_A/p_A;
+
+m_A=n_A*M_A;
+R=R0/M_A;
+
+V_B=m_B*R*T_B/p_B;
+
+V=V_A+V_B;
+m=m_A+m_B;
+T=303; //K
+
+
+disp("(a) (i) Final equilibrium pressure, p")
+p=m*R*T/V/10^5;
+disp("p=")
+disp(p)
+disp("bar")
+
+cv=R/10^3/(y-1);
+
+disp("(ii) Amount of heat transferred, Q :")
+
+U1=cv*(m_A*T_A + m_B*T_B);
+U2=m*cv*T;
+
+Q=U2-U1;
+disp("Q=")
+disp(Q)
+disp("kJ")
+
+
+disp("(b) If the vessel were insulated :")
+
+disp("(i) Final temperature,")
+
+T=cv*(m_A*T_A + m_B*T_B)/(m*cv);
+t=T-273;
+disp("T=")
+disp(t)
+disp("°C")
+
+
+disp("(ii) Final pressure")
+
+p=m*R*T/V/10^5;
+disp("p=")
+disp(p)
+disp("bar")
\ No newline at end of file diff --git a/551/CH9/EX9.13/13.sce b/551/CH9/EX9.13/13.sce new file mode 100755 index 000000000..18f783a4a --- /dev/null +++ b/551/CH9/EX9.13/13.sce @@ -0,0 +1,20 @@ +clc
+
+m_O2=3; //kg
+M_O2=32;
+
+m_N2=9; //kg
+M_N2=28;
+
+R0=8.314;
+
+R_O2=R0/M_O2;
+R_N2=R0/M_N2;
+
+x_O2=(m_O2/M_O2)/((m_O2/M_O2) + (m_N2/M_N2));
+x_N2=(m_N2/M_N2)/((m_O2/M_O2) + (m_N2/M_N2));
+
+dS=-m_O2*R_O2*log(x_O2) -m_N2*R_N2*log(x_N2);
+disp("Change in entropy =")
+disp(dS)
+disp("kJ/kg K")
\ No newline at end of file diff --git a/551/CH9/EX9.14/14.sce b/551/CH9/EX9.14/14.sce new file mode 100755 index 000000000..904df2b43 --- /dev/null +++ b/551/CH9/EX9.14/14.sce @@ -0,0 +1,17 @@ +clc
+m_N2=2.5; //kg
+M_N2=28;
+
+p_N2=15; //bar
+p_total=20; //bar
+
+n_N2=m_N2/M_N2;
+p_O2=p_total-p_N2;
+
+n_O2=p_O2/p_N2*n_N2;
+M_O2=32;
+
+m_O2=n_O2*M_O2;
+disp("Mass of O2 added =")
+disp(m_O2)
+disp("kg")
\ No newline at end of file diff --git a/551/CH9/EX9.15/15.sce b/551/CH9/EX9.15/15.sce new file mode 100755 index 000000000..20845773d --- /dev/null +++ b/551/CH9/EX9.15/15.sce @@ -0,0 +1,34 @@ +clc
+n_O2=1;
+
+//V_O2=0.21*V;
+//V_N2=0.79*V;
+M_N2=28;
+M_O2=32;
+
+disp("(i) Moles of N2 per mole of O2 :")
+n_N2=n_O2*0.79/0.21;
+disp("n_N2=")
+disp(n_N2)
+disp("moles")
+
+n=n_O2+n_N2;
+disp("(ii) p_O2 and p_N2 :")
+p=1; //atm
+
+p_O2=n_O2/n*p;
+disp("p_O2=")
+disp(p_O2)
+disp("atm")
+
+p_N2=n_N2/n*p;
+disp("p_N2=")
+disp(p_N2);
+disp("atm")
+
+
+disp("(iii) The kg of nitrogen per kg of mixture :")
+x=n_N2*M_N2/(n_N2*M_N2+n_O2*M_O2);
+disp(" The kg of nitrogen per kg of mixture =")
+disp(x)
+disp("kg N2/kg mix")
\ No newline at end of file diff --git a/551/CH9/EX9.16/16.sce b/551/CH9/EX9.16/16.sce new file mode 100755 index 000000000..54d5d5b06 --- /dev/null +++ b/551/CH9/EX9.16/16.sce @@ -0,0 +1,48 @@ +clc
+V=0.6; //m^3
+p1=12*10^5; //Pa
+p2=18*10^5; //Pa
+T=298; //K
+R0=8.314;
+x_O2=0.23;
+x_N2=0.77;
+
+n=p1*V/R0/10^3/T;
+
+//Considering 100 kg of air
+m_O2=23; //kg
+m_N2=77; //kg
+M_O2=32;
+M_N2=28;
+m=100; //kg
+
+R=(m_O2/M_O2 + m_N2/M_N2)*R0/m; //for air
+M=R0/R; //for air
+
+m=p1*V/R/T/10^3;
+
+m_O2=x_O2*m;
+disp("Mass of O2=")
+disp(m_O2)
+disp("kg")
+
+m_N2=x_N2*m;
+disp("Mass of N2=")
+disp(m_N2)
+disp("kg")
+
+
+//After adding CO2 in the vessel
+p2=18*10^5; //Pa;
+
+// p_CO2+p_N2+p_O2=18*10^5
+// p_N2 + p_O2=12*10^5
+
+p_CO2=6*10^5; //Pa
+M_CO2=44;
+R_CO2=R0/M_CO2;
+
+m_CO2=p_CO2*V/(R_CO2*10^3*T);
+disp("Mass of CO2 = ")
+disp(m_CO2)
+disp("kg")
diff --git a/551/CH9/EX9.17/17.sce b/551/CH9/EX9.17/17.sce new file mode 100755 index 000000000..5e53f2cb2 --- /dev/null +++ b/551/CH9/EX9.17/17.sce @@ -0,0 +1,36 @@ +clc
+V=6; //m^3
+%A=0.45;
+%B=0.55;
+R_A=0.288; //kJ/kg K
+R_B=0.295; //kJ/kg K
+m=2; //kg
+T=303; //K
+
+disp("(i) The partial pressures")
+m_A=%A*m;
+m_B=%B*m;
+
+p_A=m_A*R_A*10^3*T/V/10^5; //bar
+disp("p_A=")
+disp(p_A)
+disp("bar")
+
+p_B=m_B*R_B*10^3*T/V/10^5; //bar
+disp("p_B=")
+disp(p_B)
+disp("bar")
+
+
+disp("(ii) The total pressure")
+p=p_A+p_B;
+disp("p=")
+disp(p)
+disp("bar")
+
+
+disp("(iii) The mean value of R for the mixture")
+Rm=(m_A*R_A + m_B*R_B)/(m_A + m_B);
+disp("Rm=")
+disp(Rm)
+disp("kJ/kg K")
\ No newline at end of file diff --git a/551/CH9/EX9.18/18.sce b/551/CH9/EX9.18/18.sce new file mode 100755 index 000000000..a6bff6d7f --- /dev/null +++ b/551/CH9/EX9.18/18.sce @@ -0,0 +1,69 @@ +clc
+m_O2=4; //kg
+m_N2=6; //kg
+p=4*10^5; //Pa
+T=300; //K
+M_O2=32;
+M_N2=28;
+m=10; //kg
+
+disp("(i) The mole fraction of each component")
+n_O2=m_O2/M_O2;
+n_N2=m_N2/M_N2;
+
+x_O2=n_O2/(n_O2+n_N2);
+disp("x_O2=")
+disp(x_O2)
+
+x_N2=n_N2/(n_N2+n_O2);
+disp("x_N2=")
+disp(x_N2)
+
+
+disp("(ii) The average molecular weight")
+M=(n_O2*M_O2 + n_N2*M_N2)/(n_O2 + n_N2);
+disp("M=")
+disp(M)
+
+
+disp("(iii) The specific gas constant")
+R0=8.314;
+R=R0/M;
+disp("R=")
+disp(R)
+disp("kJ/kg K")
+
+disp("(iv) The volume and density")
+
+V=m*R*T*10^3/p;
+disp("V=")
+disp(V)
+disp("m^3")
+
+rho=(m_O2/V) + (m_N2/V);
+disp("density=")
+disp(rho)
+disp("kg/m^3")
+
+
+disp("(v) The partial pressures and partial volumes")
+
+p_O2=n_O2*R0*10^3*T/V/10^5; //bar
+disp("p_O2=")
+disp(p_O2)
+disp("bar")
+
+p_N2=n_N2*R0*10^3*T/V/10^5; //bar
+disp("p_N2=")
+disp(p_N2)
+disp("bar")
+
+V_O2=x_O2*V;
+disp("V_O2=")
+disp(V_O2)
+disp("m^3")
+
+V_N2=x_N2*V;
+disp("V_N2=")
+disp(V_N2)
+disp("m^3")
diff --git a/551/CH9/EX9.19/19.sce b/551/CH9/EX9.19/19.sce new file mode 100755 index 000000000..8497305c2 --- /dev/null +++ b/551/CH9/EX9.19/19.sce @@ -0,0 +1,39 @@ +clc
+cp_CO2=0.85; //kJ/kg K
+cp_N2=1.04; //kJ/kg K
+m_CO2=4; //kg
+T1_CO2=313; //K
+m_N2=8; //kg
+T1_N2=433; //K
+p2=0.7; //bar
+p1_CO2=1.4; //bar
+p1_N2=1;
+R=8.314;
+M_CO2=44;
+M_N2=28;
+R_CO2=R/M_CO2;
+R_N2=R/M_N2;
+
+disp("(i) Final temperature, T2")
+T2=(m_CO2*cp_CO2*T1_CO2 + m_N2*cp_N2*T1_N2)/(m_CO2*cp_CO2 + m_N2*cp_N2);
+disp("T2=")
+disp(T2)
+disp("K")
+
+
+disp("(ii) Change in entropy")
+n_CO2=0.0909;
+n_N2=0.2857;
+n=n_CO2 + n_N2;
+
+x_CO2=n_CO2/n;
+x_N2=n_N2/n;
+
+p2_CO2=x_CO2*p2;
+p2_N2=x_N2*p2;
+
+
+dS=m_CO2*cp_CO2*log(T2/T1_CO2) - m_CO2*R_CO2*log(p2_CO2/p1_CO2) + m_N2*cp_N2*log(T2/T1_N2) - m_N2*R_N2*log(p2_N2/p1_N2);
+disp("dS=")
+disp(dS)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH9/EX9.2/2.sce b/551/CH9/EX9.2/2.sce new file mode 100755 index 000000000..c39d55eaf --- /dev/null +++ b/551/CH9/EX9.2/2.sce @@ -0,0 +1,28 @@ +clc
+R0=8.314;
+
+M_O2=32;
+M_N2=28;
+M_Ar=40;
+M_CO2=44;
+
+R_O2=R0/M_O2; //kJ/kg K
+R_N2=R0/M_N2; //kJ/kg K
+R_Ar=R0/M_Ar; //kJ/kg K
+R_CO2=R0/M_CO2; //kJ/kg K
+
+%O2=0.2314;
+%N2=0.7553;
+%Ar=0.0128;
+%CO2=0.0005;
+
+disp("(i) Gas constant for air")
+R=%O2*R_O2 + %N2*R_N2 + %Ar*R_Ar + %CO2*R_CO2;
+disp("R=")
+disp(R)
+disp("kJ/kg K")
+
+disp("(ii) Apparent molecular weight.")
+M=R0/R;
+disp("M=")
+disp(M)
\ No newline at end of file diff --git a/551/CH9/EX9.20/20.sce b/551/CH9/EX9.20/20.sce new file mode 100755 index 000000000..b5c900bd5 --- /dev/null +++ b/551/CH9/EX9.20/20.sce @@ -0,0 +1,26 @@ +clc
+
+cv_O2=0.39; //kJ/kg K
+cv_N2=0.446; //kJ/kg K
+n_O2=1;
+n_N2=2;
+M_O2=32;
+M_N2=28;
+m_O2=32; //kg
+m_N2=2*28; //kg
+T_O2=293; //K
+T_N2=301; //K
+R0=8.314;
+p_O2=2.5*10^5; //Pa
+p_N2=1.5*10^5; //Pa
+
+T2=(m_O2*cv_O2*T_O2 + m_N2*cv_N2*T_N2)/(m_O2*cv_O2 + m_N2*cv_N2);
+
+V_O2=n_O2*R0*10^5*T_O2/p_O2;
+V_N2=n_N2*R0*10^5*T_N2/p_N2;
+V=V_O2+V_N2;
+
+dS=m_O2*[cv_O2*log(T2/T_O2) + R0/M_O2*log(V/V_O2)] + m_N2*[cv_N2*log(T2/T_N2) + R0/M_N2*log(V/V_N2)];
+disp("dS=")
+disp(dS)
+disp("kJ")
\ No newline at end of file diff --git a/551/CH9/EX9.21/21.sce b/551/CH9/EX9.21/21.sce new file mode 100755 index 000000000..8550d57c6 --- /dev/null +++ b/551/CH9/EX9.21/21.sce @@ -0,0 +1,56 @@ +clc
+cv_N2=0.744; //kJ/kg K
+cv_H2=10.352; //kJ/kg K
+cp_N2=1.041; //kJ/kg K
+cp_H2=14.476; //kJ/kg K
+
+V=0.45; //m^3
+V_H2=0.3; //m^3
+V_N2=0.15; //m^3
+
+p_H2=3*10^5; //Pa
+p_N2=6*10^5; //Pa
+
+T_H2=403; //K
+T_N2=303; //K
+
+R_H2=8.314/2;
+R_N2=8.314/28;
+
+disp("(i) Temperature of equilibrium mixture")
+
+m_H2=p_H2*V_H2/(R_H2*10^3)/T_H2;
+m_N2=p_N2*V_N2/(R_N2*10^3)/T_N2;
+
+T2=(m_H2*cv_H2*T_H2 + m_N2*cv_N2*T_N2)/(m_H2*cv_H2 + m_N2*cv_N2);
+disp("T2=")
+disp(T2)
+disp("K")
+
+
+disp("(ii) Pressure of the mixture")
+p2_H2=m_H2*R_H2*10^3*T2/V;
+p2_N2=m_N2*R_N2*10^3*T2/V;
+
+p2=p2_H2+p2_N2;
+disp("p2=")
+disp(p2/10^5)
+disp("bar")
+
+disp("(iii) Change in entropy :")
+
+dS_H2=m_H2*[cp_H2*log(T2/T_H2) - R_H2*log(p2_H2/p_H2)];
+disp("Change in entropy of H2 =")
+disp(dS_H2)
+disp("kJ/K")
+
+dS_N2=m_N2*[cp_N2*log(T2/T_N2) - R_N2*log(p2_N2/p_N2)];
+disp("Change in entropy of N2 =")
+disp(dS_N2)
+disp("kJ/K")
+
+dS=dS_H2+dS_N2;
+
+disp("Total change in entropy =")
+disp(dS)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH9/EX9.22/22.sce b/551/CH9/EX9.22/22.sce new file mode 100755 index 000000000..8887a3044 --- /dev/null +++ b/551/CH9/EX9.22/22.sce @@ -0,0 +1,40 @@ +clc
+
+cv_N2=0.745; //kJ/kg K
+cv_CO2=0.653; //kJ/kg K
+
+cp_N2=1.041; //kJ/kg K
+cp_CO2=0.842; //kJ/kg K
+
+m_N2=4; //kg
+m_CO2=6; //kg
+pmix=4; //bar
+m=m_N2+m_CO2;
+
+T1=298; //K
+T2=323; //K
+
+cv_mix=(m_N2*cv_N2 + m_CO2*cv_CO2)/(m_N2+m_CO2);
+disp("cv_mix=")
+disp(cv_mix)
+disp("kJ/kg K")
+
+cp_mix=(m_N2*cp_N2 + m_CO2*cp_CO2)/(m_N2+m_CO2);
+disp("cp_mix=")
+disp(cp_mix)
+disp("kJ/kg K")
+
+dU=m*cv_mix*(T2-T1);
+disp("Change in internal energy=")
+disp(dU)
+disp("kJ")
+
+dH=m*cp_mix*(T2-T1);
+disp("Change in enthalpy=")
+disp(dH)
+disp("kJ")
+
+dS=m_N2*cv_N2*log(T2/T1) + m_CO2*cv_CO2*log(T2/T1);
+disp("Change in entropy=")
+disp(dS)
+disp("kJ/K")
\ No newline at end of file diff --git a/551/CH9/EX9.3/3.sce b/551/CH9/EX9.3/3.sce new file mode 100755 index 000000000..314e74cd9 --- /dev/null +++ b/551/CH9/EX9.3/3.sce @@ -0,0 +1,69 @@ +clc
+p=1; //bar
+
+//For oxygen
+m_O2=0.2314;
+M_O2=32;
+n_O2=m_O2/M_O2;
+
+//For Nitrogen
+m_N2=0.7553;
+M_N2=28;
+n_N2=m_N2/M_N2;
+
+//For Argon
+m_Ar=0.0128;
+M_Ar=40;
+n_Ar=m_Ar/M_Ar;
+
+//For CO2
+m_CO2=0.0005;
+M_CO2=44;
+n_CO2=m_CO2/M_CO2;
+
+
+n=n_O2 + n_N2 + n_Ar + n_CO2;
+
+//Let Vi/V be A
+
+A_O2=n_O2/n * 100;
+disp("Vi/V of O2=")
+disp(A_O2)
+disp("%")
+
+A_N2=n_N2/n * 100;
+disp("Vi/V of N2=")
+disp(A_N2)
+disp("%")
+
+A_Ar=n_Ar/n *100;
+disp("Vi/V of Ar")
+disp(A_Ar)
+disp("%")
+
+A_CO2=n_CO2/n * 100;
+disp("Vi/V of CO2=")
+disp(A_CO2)
+disp("%")
+
+
+P_O2=n_O2/n*p;
+disp("Partial pressure of O2=")
+disp(P_O2)
+disp("bar")
+
+P_N2=n_N2/n*p;
+disp("Partial pressure of N2=")
+disp(P_N2)
+disp("bar")
+
+P_Ar=n_Ar/n*p;
+disp("Partial pressure of Ar=")
+disp(P_Ar)
+disp("bar")
+
+P_CO2=n_CO2/n*p;
+disp("Partial pressure of CO2=")
+disp(P_CO2)
+disp("bar")
+
diff --git a/551/CH9/EX9.4/4.sce b/551/CH9/EX9.4/4.sce new file mode 100755 index 000000000..81928213a --- /dev/null +++ b/551/CH9/EX9.4/4.sce @@ -0,0 +1,67 @@ +clc
+p=1*10^5; //Pa
+T=293; //K
+n_CO2=1; //moles of CO2
+n=4; //moles of air
+M_CO2=44;
+M_N2=28;
+M_O2=32;
+
+//Let A be the volumeetric analysis
+A_O2=0.21;
+A_N2=0.79;
+
+n_O2=A_O2*n;
+n_N2=A_N2*n;
+
+disp("(i) The masses of CO2, O2 and N2, and the total mass")
+
+m_CO2=n_CO2*M_CO2;
+disp("Mass of CO2=")
+disp(m_CO2)
+disp("kg")
+
+m_O2=n_O2*M_O2;
+disp("Mass of O2=")
+disp(m_O2)
+disp("kg")
+
+m_N2=n_N2*M_N2;
+disp("Mass of N2=")
+disp(m_N2)
+disp("kg")
+
+m=m_CO2 + m_O2 + m_N2;
+disp("Total mass =")
+disp(m)
+disp("kg")
+
+
+disp("(ii) The percentage carbon content by mass")
+//Since the molecular weight of carbon is 12, therefore, there are 12 kg of carbon present for every mole of CO2
+m_C=12; //kg
+
+%C=m_C/m*100;
+disp("Percentage carbon in mixture")
+disp(%C)
+disp("%")
+
+
+disp("(iii) The apparent molecular weight and the gas constant for the mixture")
+n=n_CO2 + n_O2 + n_N2;
+M=n_CO2/n*M_CO2 + n_O2/n*M_O2 + n_N2/n*M_N2;
+disp("Apparent Molecular weight")
+disp(M)
+
+R0=8.314;
+R=R0/M;
+disp("Gas constant for the mixture=")
+disp(R)
+disp("kJ/kg K")
+
+
+disp("(iv) The specific volume of the mixture")
+v=R*10^3*T/p;
+disp("specific volume=")
+disp(v)
+disp("m^3/kg")
diff --git a/551/CH9/EX9.5/5.sce b/551/CH9/EX9.5/5.sce new file mode 100755 index 000000000..350304629 --- /dev/null +++ b/551/CH9/EX9.5/5.sce @@ -0,0 +1,29 @@ +clc
+p=1*10^5; //Pa
+T=298; //K
+M_H2=2;
+M_O2=32;
+R0=8314;
+
+// ratio = V_H2/V_O2=2;
+ratio=2;
+
+disp("(i) The mass of O2 required")
+//Let the mass of O2 per kg of H2 = x kg
+m_H2=1; //kg
+n_H2=m_H2/M_H2;
+
+// n_O2=x/M_O2
+x=M_O2*n_H2/ratio;
+disp("Mass of O2 per kg of H2=")
+disp(x)
+disp("kg")
+
+
+disp("(ii) The volume of the container")
+n_O2=x/M_O2;
+n=n_H2 + n_O2;
+V=n*R0*T/p;
+disp("V=")
+disp(V)
+disp("m^3")
\ No newline at end of file diff --git a/551/CH9/EX9.6/6.sce b/551/CH9/EX9.6/6.sce new file mode 100755 index 000000000..cdb8a3ac8 --- /dev/null +++ b/551/CH9/EX9.6/6.sce @@ -0,0 +1,27 @@ +clc
+
+//Let composition of mixture by volume be denoted by c1
+//Let Final composition desired be denoted by c2
+
+c1_H2=0.78;
+c1_CO=0.22;
+
+c2_H2=0.52;
+c2_CO=0.48;
+
+M_H2=2;
+M_CO=28;
+
+M=c1_H2*M_H2 + c1_CO*M_CO;
+
+// Let x kg of mixture be removed and y kg of CO be added.
+
+x=(c1_H2 - c2_H2)/c1_H2*M;
+disp("Mass of mixture removed =")
+disp(x)
+disp("kg")
+
+y=M_CO/M*x;
+disp("Mass of CO added=")
+disp(y)
+disp("kg")
\ No newline at end of file diff --git a/551/CH9/EX9.7/7.sce b/551/CH9/EX9.7/7.sce new file mode 100755 index 000000000..bf9d035b8 --- /dev/null +++ b/551/CH9/EX9.7/7.sce @@ -0,0 +1,61 @@ +clc
+
+ratio=1/8; //volume ratio; v1/v2
+T1=1223; //K
+
+cp_CO2=1.235; //kJ/kg K
+cp_O2=1.088; //kJ/kg K
+cp_N2=1.172; //kJ/kg K
+
+n_CO2=0.13;
+n_O2=0.125;
+n_N2=0.745;
+
+M_CO2=44;
+M_O2=32;
+M_N2=28;
+
+m_CO2=M_CO2*n_CO2;
+m_O2=M_O2*n_O2;
+m_N2=M_N2*n_N2;
+
+m=m_CO2 + m_O2 + m_N2;
+
+// Let Fraction by mass be denoted by F
+F_CO2=m_CO2/m;
+F_O2=m_O2/m;
+F_N2=m_N2/m;
+
+
+cp=F_CO2*cp_CO2 + F_O2*cp_O2 + F_N2*cp_N2;
+
+R0=8.314;
+R=F_CO2*R0/M_CO2 + F_O2*R0/M_O2 + F_N2*R0/M_N2;
+
+cv=cp - R;
+n=1.2;
+
+disp("(i) The workdone")
+T2=T1*(ratio)^(n-1);
+W=R*(T1-T2)/(n-1);
+disp("W=")
+disp(W)
+disp("kJ/kg")
+
+
+disp("(ii) The heat flow")
+du=cv*(T2-T1);
+Q=du + W;
+disp("Q=")
+disp(Q)
+disp("kJ/kg")
+
+
+disp("(iii) Change of entropy per kg of mixture")
+ds_1A=R*log(1/ratio); //isothermal process
+ds_2A=cv*log(T1/T2);
+
+ds_12=ds_1A - ds_2A;
+disp("change of entropy=")
+disp(ds_12)
+disp("kJ/kg K")
\ No newline at end of file diff --git a/551/CH9/EX9.8/8.sce b/551/CH9/EX9.8/8.sce new file mode 100755 index 000000000..97140a003 --- /dev/null +++ b/551/CH9/EX9.8/8.sce @@ -0,0 +1,44 @@ +clc
+
+M_CO2=44;
+M_H2=2;
+M_N2=28;
+M_CH4=16;
+M_CO=28;
+
+// Let volumetric analysis be denoted by V
+V_CO=0.28;
+V_H2=0.13;
+V_CH4=0.04;
+V_CO2=0.04;
+V_N2=0.51;
+
+Cp_CO=29.27; //kJ/mole K
+Cp_H2=28.89; //kJ/mole K
+Cp_CH4=35.8; //kJ/mole K
+Cp_CO2=37.22; //kJ/mole K
+Cp_N2=29.14; //kJ/mole K
+
+R0=8.314;
+
+Cp=V_CO*Cp_CO + V_H2*Cp_H2 + V_CO2*Cp_CO2 + V_CH4*Cp_CH4 + V_N2*Cp_N2;
+disp("Cp=")
+disp(Cp)
+disp("kJ/mole K")
+
+Cv=Cp-R0;
+disp("Cv=")
+disp(Cv)
+disp("kJ/mole K")
+
+M=V_CO*M_CO + V_H2*M_H2 + V_CO2*M_CO2 + V_CH4*M_CH4 + V_N2*M_N2;
+
+cp=Cp/M;
+disp("cp=")
+disp(cp)
+disp("kJ/kg K")
+
+cv=Cv/M;
+disp("cv")
+disp(cv)
+disp("kJ/kg K")
\ No newline at end of file diff --git a/551/CH9/EX9.9/9.sce b/551/CH9/EX9.9/9.sce new file mode 100755 index 000000000..25948018c --- /dev/null +++ b/551/CH9/EX9.9/9.sce @@ -0,0 +1,58 @@ +clc
+
+p=1.3; //bar
+R0=8.314;
+
+M_CO2=44;
+M_O2=32;
+M_N2=28;
+M_CO=28;
+
+m_O2=0.1;
+m_N2=0.7;
+m_CO2=0.15;
+m_CO=0.05;
+
+//Considering 1 kg of mixture
+m=1; //kg
+
+//let moles be denoted by n
+n_O2=m_O2/M_O2;
+n_N2=m_N2/M_N2;
+n_CO2=m_CO2/M_CO2;
+n_CO=m_CO/M_CO;
+
+M=1/(m_O2/M_O2 + m_N2/M_N2 + m_CO2/M_CO2 + m_CO/M_CO);
+
+n=m/M;
+
+x_O2=n_O2/n;
+x_N2=n_N2/n;
+x_CO2=n_CO2/n;
+x_CO=n_CO/n;
+
+disp("(i) Partial pressures of the constituents")
+P_O2=x_O2*p;
+disp("Partial pressure of O2=")
+disp(P_O2)
+disp("bar")
+
+P_N2=x_N2*p;
+disp("Partial pressure of N2=")
+disp(P_N2)
+disp("bar")
+
+P_CO2=x_CO2*p;
+disp("Partial pressure of CO2=")
+disp(P_CO2)
+disp("bar")
+
+P_CO=x_CO*p;
+disp("Partial pressure of CO=")
+disp(P_CO)
+disp("bar")
+
+disp("Gas constant of mixture =")
+R_mix=R0/M;
+disp(R_mix)
+disp("kJ/kg K")
\ No newline at end of file |