diff options
Diffstat (limited to '617')
61 files changed, 1224 insertions, 0 deletions
diff --git a/617/CH10/EX10.1/Example10_1.sci b/617/CH10/EX10.1/Example10_1.sci new file mode 100755 index 000000000..b272f179c --- /dev/null +++ b/617/CH10/EX10.1/Example10_1.sci @@ -0,0 +1,16 @@ +clc();
+clear;
+
+// To determne the heat transfer coefficient for steam
+y=1.9; // Density in slug/ft^-2
+u=0.0354; // Viscosity in slug/ft-hr
+k=0.376; // Thermal conductivity in Btu/hr-ft-degF
+l=32600; // Heat of condensation in Btu/slug
+Tg=142; // Temperature of steam in degF
+Tw=138; // Temperature of wall in degF
+delT=Tg-Tw; // Temperature driving force in degF
+g=418*10^6; // Gravity in ft/sec^2
+L=1/12; // Outside diameter of horizontal tube in ft
+C=0.725; // For horizontal tube
+h=C*(g*y^2*l*k^3/(L*u*delT))^0.25; // Heat transfer coefficient in Btu/hr-ft^2-degF
+printf("The heat transfer coefficient for steam condensing on a horizontal tube is %d Btu/hr-ft^2-degF",h);
\ No newline at end of file diff --git a/617/CH11/EX11.1/Example11_1.sci b/617/CH11/EX11.1/Example11_1.sci new file mode 100755 index 000000000..4d7ac498a --- /dev/null +++ b/617/CH11/EX11.1/Example11_1.sci @@ -0,0 +1,10 @@ +clc();
+clear;
+
+// To calculate the net radiant interchange between two parallel black planes
+
+T1=1660/100; // Temperature of first black plane in degR
+T2=1260/100; // Temperature of second black plane in degR
+s=0.174; // Stephan Boltzman's constant
+q=s*(T1^4-T2^4);
+printf("The net radiant interchange between two bodies of unit area is %d Btu/hr-ft^2",q);
\ No newline at end of file diff --git a/617/CH11/EX11.2/Example11_2.sci b/617/CH11/EX11.2/Example11_2.sci new file mode 100755 index 000000000..1315ae08f --- /dev/null +++ b/617/CH11/EX11.2/Example11_2.sci @@ -0,0 +1,14 @@ +clc()
+// To calculate the net radiant interchange between floor and roof of a furnace
+
+
+A1=15*15; // Area of floor in ft^2
+A2=A1; // Area of roof in ft^2
+T1=2460/100; // Temperature of floor in degR
+T2=1060/100; // temperature of roof in degR
+s=0.174; // Stephan Boltzman's constant
+// S/L=1.5, So considering graph F12=0.31
+
+F12=0.31;
+q=s*F12*A1*(T1^4-T2^4);
+printf("The net radiant interchange between two bodies of unit area is %d Btu/hr-ft^2",q);
\ No newline at end of file diff --git a/617/CH11/EX11.3/Example11_3.sci b/617/CH11/EX11.3/Example11_3.sci new file mode 100755 index 000000000..e5308472c --- /dev/null +++ b/617/CH11/EX11.3/Example11_3.sci @@ -0,0 +1,17 @@ +clc()
+// To calculate he net radiant interchange between floor of a furnace and the wall
+
+x=6; // length of wall in ft
+y=12; // breadth of wall in ft
+z=18; // height of wall in ft
+A1=x*y;
+s=0.174; // Stephan Boltzman's constant
+T1=1000; // Temperature of floor in degF
+T2=500; // Temperature of wall in degF
+Y=y/x; // Ratios
+Z=z/x;
+
+// Seeing the graph, F12 could be found out
+F12=0.165;
+q12=s*F12*A1*((((T1+460)/100)^4)-((T2+460)/100)^4); // Radiant interchange
+printf("The net radiant interchange between two bodies of unit area is %d Btu/hr-ft^2",q12);
diff --git a/617/CH11/EX11.4/Example11_4.sci b/617/CH11/EX11.4/Example11_4.sci new file mode 100755 index 000000000..0f01515cd --- /dev/null +++ b/617/CH11/EX11.4/Example11_4.sci @@ -0,0 +1,15 @@ +clc();
+clear;
+// To calculate the radiant interchange between two black discs
+
+D=10/12; // Diameter of black disc
+L=5/12; // Distance between two discs
+T1=(1500+460)/100; // Temperature of disc 1 in degR
+T2=(1000+460)/100; // Temperature of disc 2 in degR
+// From the ratio of S/L, the value of F1r2 can be found out
+F1r2=0.669; // Shape factor
+A1=%pi*D*D/4; // Area of disc 1 in ft^2
+A2=%pi*D*D/4; // Area of disc 2 in ft^2
+s=0.174; // Stephan Boltzman's constant
+q12=s*F1r2*A1*((T1^4)-(T2^4)); // Radiant interchange in Btu/hr
+printf("The net radiant interchange between two parallel black discs is %d Btu/hr",q12);
\ No newline at end of file diff --git a/617/CH11/EX11.5/Example11_5.sci b/617/CH11/EX11.5/Example11_5.sci new file mode 100755 index 000000000..81234a300 --- /dev/null +++ b/617/CH11/EX11.5/Example11_5.sci @@ -0,0 +1,15 @@ +clc();
+clear;
+// To calculate the net radiant interchange between two parallel black discs
+
+T1=(1500+460)/100; // Temperature of plane 1 in degR
+T2=(1000+460)/100; // Temperature of plane 2 in degR
+e1=0.8; // Emmisivity for higher temperature
+e2=0.6; // Emmisivity for lower temperature
+s=0.174; // Stephan Boltzman's constant
+D=10/12; // Diameter of disc in ft
+A=%pi/4*D^2; // Area of disc in ft^2
+F1r2=0.669;
+F1r2g=1/((1/F1r2)+(1/e1)+(1/e2)-2); // Shape factor
+q12=s*F1r2g*A*((T1^4)-(T2^4)); // Radiant interchange in Btu/hr
+printf("The net radiant interchange between two parallel very large planes per square foot is %d Btu/hr",q12);
\ No newline at end of file diff --git a/617/CH11/EX11.6/Example11_6.sci b/617/CH11/EX11.6/Example11_6.sci new file mode 100755 index 000000000..6d5c4bf1c --- /dev/null +++ b/617/CH11/EX11.6/Example11_6.sci @@ -0,0 +1,14 @@ +clc();
+clear;
+
+// To calculate the net radiant interchange between two parallel planes
+
+T1=1460/100; // Temperature of first black plane in degK
+T2=1060/100; // temperature of second black plane in degK
+s=0.174; // Stephan Boltzman's constant
+e1=0.9; // Emmisivity for higher temperature
+e2=0.7; // Emmisivity for higher temperature
+F1r2=1/((1/e1)+(1/e2)-1); // Shape factor
+
+q=s*F1r2*(T1^4-T2^4);
+printf("The net radiant interchange between two bodies of unit area is %d Btu/hr-ft^2",q);
\ No newline at end of file diff --git a/617/CH11/EX11.7/Example11_7.sci b/617/CH11/EX11.7/Example11_7.sci new file mode 100755 index 000000000..04d25e150 --- /dev/null +++ b/617/CH11/EX11.7/Example11_7.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To calculate the net radiant interchange per foot length of pipe of 2 in. standard diameter
+
+e=0.8; // emmisivity of pipe metal
+D=2.375/12; // Diameter of pipe in ft
+s=0.174; // Stephans Boltzman's constant
+T1=(300+460)/100; // Temperature of disc 1 in degF
+T2=(80+460)/100; // Temperature of disc 2 in degF
+A1=%pi*D; // Area of one foot of pipe in ft^2
+q12=s*e*A1*((T1^4)-(T2^4)); // Radiant interchange in Btu/hr
+printf("The net radiant interchange per foot length of pipe is %.1f Btu/hr-ft",q12);
\ No newline at end of file diff --git a/617/CH12/EX12.1/Example12_1.sci b/617/CH12/EX12.1/Example12_1.sci new file mode 100755 index 000000000..ace91e5d6 --- /dev/null +++ b/617/CH12/EX12.1/Example12_1.sci @@ -0,0 +1,17 @@ +clc();
+clear;
+
+// To calculate the heat loss per linear foot from a 4-in. (out-side diameter=4.5 in.)nominal horizontal steel pipe covered with 1 in.of insulation
+
+D=4.5/12; // Outer diameter of pipe in ft
+D2=6.5/12; // Outer diameter of insulation in ft
+k=0.035; // Thermal conductivity in Btu/hr-ft-degF
+T1=400; // Temperature of pipe in degF
+T3=70; // Temperature of air in degF
+T2=120; // Assumed temperature in degF
+h=2*k*(T1-T2)/(D2*(T2-T3)*log(D2/D)); // Sum of coefficient of convection and radiation
+delT=T2-T3; // Temperature differnce in degF
+T2=120; // Assumed temperature in degF
+printf("The assumption of T2=120 comes out to be satisfactory and hc+hr=%.1f \n ",h);
+q=h*%pi*D2*delT; // Heat loss in Btu/hr
+printf("The heat loss per unit foot of pipe is %d Btu/hr-ft",q);
diff --git a/617/CH12/EX12.2/Example12_2.sci b/617/CH12/EX12.2/Example12_2.sci new file mode 100755 index 000000000..9da1311ab --- /dev/null +++ b/617/CH12/EX12.2/Example12_2.sci @@ -0,0 +1,15 @@ +clc();
+clear;
+
+// To calculate the heat loss per square foot from an uninsulated 2 inch sch. pipe
+
+D=2.375/12; // Outer diameter of pipe in ft
+k=0.035; // Thermal conductivity in Btu/hr-ft-degF
+T1=400; // Temperature of pipe in degF
+T2=70; // Temperature of air in degF
+delT=T1-T2; // Temperature differnce in degF
+T2=120; // Assumed temperature in degF
+h=3.67;
+// As seen from the table , for delT=330. the value of hc+hr=3.67
+q=h*delT; // Heat loss in Btu/hr
+printf("The heat loss per square foot of pipe is %d Btu/hr-ft",q);
diff --git a/617/CH14/EX14.1/Example14_1.sci b/617/CH14/EX14.1/Example14_1.sci new file mode 100755 index 000000000..ad5100c43 --- /dev/null +++ b/617/CH14/EX14.1/Example14_1.sci @@ -0,0 +1,20 @@ +clc();
+clear;
+
+// To calculate the true gas temperature
+
+D1=36/12; // diameter of circular duct in ft
+D2=5/96; // diameter of tube in ft
+Tl=800; // Temperature of tube in degF
+To=500; // Temperature of duct in degF
+k=0.02; // Thermal conductivity in lb/ft^-2-hr
+u=0.18*(10^-9)*(3600^2); // Viscosity in slug/ft-hr
+p=0.04/32.2; // Density in slug/ft^3
+n=u/p; // Kinematic viscosity in ft^2/hr
+v=15*3600; // Velocity in ft/hr
+e=0.8; // Emmisivity
+Nre=v*D2/n; // Reynolds number
+Nnu=0.3*(Nre^0.57); // Nusselt number
+h=Nnu*k/D2; // Heat transfer coefficient
+Tg=Tl+0.174*e*((((Tl+460)/100)^4)-((To+460)/100)^4)/h; // Gas temperature in degF
+printf("The temperature of gas is %d degF",Tg);
\ No newline at end of file diff --git a/617/CH15/EX15.1/Example15_1.sci b/617/CH15/EX15.1/Example15_1.sci new file mode 100755 index 000000000..21e1ae1d0 --- /dev/null +++ b/617/CH15/EX15.1/Example15_1.sci @@ -0,0 +1,33 @@ +clc();
+clear;
+
+// To calculate the pressure drop , heat loss per hour and fil coefficient of heat transfer
+
+Tm=70; // Average air temperature in degF
+Tw=60; // Pipe wall temperature in degF
+thm=Tm-Tw; // Mean temperature difference in degF
+// Thm is so small that the fluid properties may be based on 70 degF
+
+v=30; // Velocity in ft/sec
+L=1000; // Length of pipe
+D=3/12; // Diameter in ft
+y=0.15; // Specific weight in lb/ft^3
+p=0.15/32.2; // Density in slug/ft^3
+u=0.00137; // Viscosity in slug/ft/hr
+Nre=v*3600*D*p/u; // Reynolds number
+f=0.08/(Nre)^.25; // Nusselt number
+delp=2*f*L*p*(v^2)/D; // Pressure drop in lb/sq.in
+printf("The pressure drop is %d lb/sq.ft \n ",delp);
+
+
+cp=0.24*32.2; // Specific heat capacity in slug/degF
+Cp=0.24*0.15; // Heat capacity in Btu/ft^3-degF
+k=0.0148; // Thermal conductivity in Btu/ft-hr-degF
+Npr=u*cp/k; // Prandtls number
+phi=sqrt(Npr)/(1+(750*sqrt(Npr)/Nre)+7.5*(Npr^0.25)/sqrt(Nre));
+A=%pi*L*D; // Area in ft^2
+q=phi*f*Cp*A*v*thm*3600/(2*Npr); // Heat loss in Btu/hr
+printf("Heat loss per hour of air is %f Btu/hr \n ",phi);
+h=q/(A*thm); // Film coefficient
+printf("The film coefficient of heat transfer on the inner pipe wall is %.1f Btu/hr-ft^2-degF",h);
+
diff --git a/617/CH16/EX12.3/Example16_3.sci b/617/CH16/EX12.3/Example16_3.sci new file mode 100755 index 000000000..2e61d6961 --- /dev/null +++ b/617/CH16/EX12.3/Example16_3.sci @@ -0,0 +1,17 @@ +clc();
+clear;
+
+// To compute the ammonia diffusing through the stagnant air
+
+x=0.1/12; // thickness of still air layer in ft
+T=77+460; // temperature in degR
+p=1; // Atmospheric pressure in atm
+pa1=0.3; // Pressure of ammonia in still air in atm
+pb1=p-pa1; // pressure of air in atm
+pa2=0; // pressure of ammonia in the absorption plane
+pb2=p-pa2; // pressure of air in absorption plane
+pbm=(pb2-pb1)/(log(pb2/pb1)); // Logarithmic mean pressure
+D=0.914; // Diffusion coefficient for ammonia
+R=0.729; // Gas constant in ft^3-atm/lb-mole-degR
+N=D*p*(pa1-pa2)/(R*T*x*pbm);
+printf("The amount of ammonia diffusing through the stagnant air is %.1f lb-mol/hr-ft^2",N);
\ No newline at end of file diff --git a/617/CH16/EX16.1/Example16_1.sci b/617/CH16/EX16.1/Example16_1.sci new file mode 100755 index 000000000..bbcc250b8 --- /dev/null +++ b/617/CH16/EX16.1/Example16_1.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To compute the diffusion coeffiient for water vapour in air
+
+T=25+273; // Temperature in degK
+p=1; // Pressure in atm
+Va=18.9; // Molecular volume of water vapour in cm^3/gm-mol
+Vb=29.9; // Molecular volume of air in cm^3/gm-mol
+Ma=18; // Molecular weight of water vapour in gm/mol
+Mb=29; // Molecular weight of air in gm/mol
+Dab=0.0043*(T^1.5)*sqrt((1/Ma)+(1/Mb))/(p*(Va^(1/3)+Vb^(1/3))^2);
+printf("The diffusion coefficient is %.3f cm^3/sec ",Dab);
\ No newline at end of file diff --git a/617/CH16/EX16.2/Example16_2.sci b/617/CH16/EX16.2/Example16_2.sci new file mode 100755 index 000000000..32375dc82 --- /dev/null +++ b/617/CH16/EX16.2/Example16_2.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To compute the diffusion coeffiient for benzene in air
+
+T=25+273; // Temperature in degK
+p=1; // Pressure in atm
+Va=96; // Molecular volume of benzene in cm^3/gm-mol
+Vb=29.9; // Molecular volume of air in cm^3/gm-mol
+Ma=78; // Molecular weight of benzene in gm/mol
+Mb=29; // Molecular weight of air in gm/mol
+Dab=0.0043*(T^1.5)*sqrt((1/Ma)+(1/Mb))/(p*(Va^(1/3)+Vb^(1/3))^2);
+printf("The diffusion coefficient is %.3f cm^3/sec ",Dab);
\ No newline at end of file diff --git a/617/CH16/EX16.4/Example16_4.sci b/617/CH16/EX16.4/Example16_4.sci new file mode 100755 index 000000000..4ddfede85 --- /dev/null +++ b/617/CH16/EX16.4/Example16_4.sci @@ -0,0 +1,12 @@ +clc();
+clear;
+
+// To compute the hydrogen loss per unit pipe by diffusion
+
+ri=3/96; // Inner radius of pipe in ft
+ro=1/24; // Outer radius of pipe in ft
+Ca1=0.0003; // Concentration at the inner hose of pipe in lb-mol/ft^2
+Ca2=0; // Concentration at the outer surface
+D=0.7*10^-5; // Diffusion coefficient of hydrogen in rubber in ft^2/hr
+N=2*%pi*D*(Ca1-Ca2)/log(ro/ri); // Rate of diffusion in lb-mol/hr
+printf("The rate of diffusion iof hydrogen in rubber is %.2f*10^-8 lb-mole/hr",N*10^8);
\ No newline at end of file diff --git a/617/CH16/EX16.5/Example16_5.sci b/617/CH16/EX16.5/Example16_5.sci new file mode 100755 index 000000000..62eb97ce7 --- /dev/null +++ b/617/CH16/EX16.5/Example16_5.sci @@ -0,0 +1,26 @@ +clc();
+clear;
+
+// To calculate the amount of water evaporated per hour per square foot of surface area
+
+u=0.0437; // Viscosity in lb/hr-ft
+rho=0.077; // Density in lb-ft^2
+D=0.992; // Diameter of pipe in ft
+v=4*3600; // Velocity in ft/sec
+L=6/12; // Length of pipe parallel to direction of air flow in ft
+p=14.7; // Atmospheric pressure in psi
+T=460+65; // Temperature in degR
+
+// Heat transfer equation for laminar flow of a flat surface
+Nre=L*v*rho/u; // Reynolds number
+Ns=u/(rho*D); // Schimdt mumber
+Nnu=0.662*(Ns)^(1/3)*sqrt(Nre); // Nusselt number
+hmc=Nnu*D/L; // Heat transfer coefficient
+pv1=0.144; // Vapour pressure at 40% humidity
+pv2=0.252; // Vapour pressure at saturation
+pa1=p-pv1; // Absolute pressure of air at 40% rel. humidity in psi
+pa2=p-pv2; // Absolute pressure of saturated air in psi
+pbm=(pa1+pa2)/2; // Log mean pressure in psi
+R=1544; // Universal gas constant in ft^3-psi/lbmol-degR
+N=hmc*p*(pa1-pa2)*144/(R*T*pbm);
+printf("The amount of water evaporated per hour is %.4f lb mol/hr-ft^2",N);
\ No newline at end of file diff --git a/617/CH16/EX16.6/Example16_6.sci b/617/CH16/EX16.6/Example16_6.sci new file mode 100755 index 000000000..d814b3803 --- /dev/null +++ b/617/CH16/EX16.6/Example16_6.sci @@ -0,0 +1,32 @@ +clc();
+clear;
+
+// To estimate the amount of water transferred
+
+u=0.047; // Viscosity in lb/hr-ft
+rho=0.069; // Density in lb-ft^2
+D=0.992; // Diameter of pipe in ft
+v=7.5*3600; // Velocity in ft/sec
+L=2; // Length of pipe parallel to direction of air flow in ft
+M=0.992; // Molecular weight
+p=14.696; // Atmospheric pressure in psi
+T=460+65; // Temperature in degR
+M=29; // molecular weight of air
+M2=18; // Molecular weight of water vapour
+A=4; // Area of water surface in ft^2
+// Heat transfer equation for laminar flow of a flat surface
+Nre=L*v*rho/u; // Reynolds number
+
+// Assuming the case that of a fluid flowing parallel to a flat plate , jm=0.0039
+jm=0.0039;
+Ns=u/(rho*D); // Schimdt mumber
+Gm=v*rho/M; // Mole flow rate
+pv1=0.672; // Vapour pressure at 40% humidity
+pv2=0.600; // Vapour pressure at saturation
+pa1=p-pv1; // Absolute pressure of air at 40% rel. humidity in psi
+pa2=p-pv2; // Absolute pressure of saturated air in psi
+pbm=(pa1+pa2)/2; // Log mean pressure in psi
+hmp=jm*Gm/(pbm*144*Ns^(2/3)); // Heat transfer coefficient in lbmol/ft^2-hr-psi
+N=hmp*(pv1-pv2)*144; // Mass transfer rate in lb mol/hr-ft^2
+W=N*A*M2;
+printf("The amount of water evaporated per hour is %.3f lb mol/hr-ft^2",W);
\ No newline at end of file diff --git a/617/CH16/EX16.7/Example16_7.sci b/617/CH16/EX16.7/Example16_7.sci new file mode 100755 index 000000000..e8b91d617 --- /dev/null +++ b/617/CH16/EX16.7/Example16_7.sci @@ -0,0 +1,34 @@ +clc();
+clear;
+
+// To calculate the amount of water evaporated in per hour for a square foot of water surface
+
+u=3.82*10^-7; // Viscosity in lb-sec/ft^2
+rho=2.3*10^-3; // Density in lbsec^2/ft^4
+A=1; // Area in ft^2
+Cp=0.24; // Specific heat capacity in abtu/lbm-degF
+v=4*3600; // Velocity in ft/sec
+k=0.015; // Thermal conductivity in Btu/hr-ft-degF
+p=14.7; // Atmospheric pressure in psi
+M=29; // Avg. molecular weight of air
+T1=70+460; // Temperature of still air in degF
+T2=90+460; // temperature of surface of water in degF
+L=1; // For characteristic of 1 ft
+D=0.992; // Diffusivity in ft^2/sec
+
+// Heat transfer equation for laminar flow of a flat surface
+Ngr=32.2*L^3*((T2/T1)-1)/(u/rho)^2; // Grasshops number
+Npr=u*3600*Cp*32.2/k; // Prandtls number
+Nnu=0.75*(Ngr*Npr)^.25; // Nusselt number
+h=Nnu*k/L; // Heat transfer coefficient
+Ns=u*3600/(rho*D); // Schimdt mumber
+hmc=h*D*(Ns/Npr)^0.25/k; // Heat transfer coe
+pv1=0.18; // Vapour pressure at 40% humidity
+pv2=0.69; // Vapour pressure at saturation
+pa1=p-pv1; // Absolute pressure of air at 40% rel. humidity in psi
+pa2=p-pv2; // Absolute pressure of saturated air in psi
+pbm=(pa1+pa2)/2; // Log mean pressure in psi
+R=1544; // Universal gas constant in ft^3-psi/lbmol-degR
+T=(T1+T2)/2; // Average temperature in degR
+N=hmc*p*(pv2-pv1)*144/(R*T*pbm)*18; // mass transfer rate in lbmol/hr-ft^2
+printf("The amount of water evaporated per hour is %.4f lb mol/hr-ft^2",N);
diff --git a/617/CH16/EX16.8/Example16_8.sci b/617/CH16/EX16.8/Example16_8.sci new file mode 100755 index 000000000..26928ec34 --- /dev/null +++ b/617/CH16/EX16.8/Example16_8.sci @@ -0,0 +1,18 @@ +clc();
+clear;
+
+// To know the moisture content of air
+
+Td=70+460; // Dry bulb temperature in degR
+Tw=60+460; // Wet bulb temperature in degR
+a=0.26; // Ratio of coefficients ie. h/hmw from table
+L=1059.9; // Latent heat Btu/lbmol
+p=14.7; // Atmospheric pressure in psi
+pa=0.259; // Partial pressure of water in psi
+Ma=18; // Molecular weight of water vapour
+Mb=29; // Molecular weight of air
+
+Wwb=pa*Ma/(Mb*(p-pa)); // Absolte dry bulb humidity of air
+Wdb=Wwb-(a*(Td-Tw)/L); // Absolte dry bulb humidity of air
+printf("The humidity of air at dry conditions is %.5f lbm/lbm of dry air",Wdb);
+
\ No newline at end of file diff --git a/617/CH16/EX16.9/Example16_9.sci b/617/CH16/EX16.9/Example16_9.sci new file mode 100755 index 000000000..f75a49d59 --- /dev/null +++ b/617/CH16/EX16.9/Example16_9.sci @@ -0,0 +1,18 @@ +clc();
+clear;
+
+// To estimate the mass transfer coefficient
+
+v=20; // Velocity of air ammonia mixture in ft/sec
+Npr=0.72; // Prandtls number
+Ns=0.60; // Schimdt number
+pbm=14.7; // log mean pressure in psi
+Mm=29; // Molecular weight of mixture
+Mv=17; // Molecular weight of ammonia
+Ma=29; // Molecular weight of air
+Cp=0.24; // specific heat capacity in Btu/lbm-degF
+h=8; // Heat transfer coefficient
+p=1; // Atospheric pressure in atm
+
+hmp=h*Mv*(Npr/Ns)^(2/3)/(Cp*p*Ma); // Mass transfer coefficient based on pressure
+printf("The mass transfer coefficient based on pressure is %.1f lbm/hr-ft^2-atm",hmp);
\ No newline at end of file diff --git a/617/CH3/EX3.1/Example3_1.sci b/617/CH3/EX3.1/Example3_1.sci new file mode 100755 index 000000000..6a40fa31a --- /dev/null +++ b/617/CH3/EX3.1/Example3_1.sci @@ -0,0 +1,12 @@ +clear; +clc(); + +// To find heat loss per square feet of wall surface per hour + +deltax=9/12; // thickness of wall in ft +k=0.18; // thermal conductivity of wall in B/hr-ft-degF +t1=1500; // inside temperature of oven wall in degF +t2=400; // outside temperature of oven wall in degF + +q=k*(t1-t2)/deltax; // heat loss in Btu/hr +printf("\n The heat loss for each square foot of wall surface is %d Btu/hr-ft^2",q);
\ No newline at end of file diff --git a/617/CH3/EX3.10/Example3_10.sci b/617/CH3/EX3.10/Example3_10.sci new file mode 100755 index 000000000..bdd0540cd --- /dev/null +++ b/617/CH3/EX3.10/Example3_10.sci @@ -0,0 +1,19 @@ +clear;
+clc();
+
+// To find the total heat flow per foot of depth through the sction and the shape factor
+
+k=0.9; // thermal conductivity of section material in Btu/hr-ft-degF
+
+// Heat is considered to flow through fictitious rods and only half of the heat flows through symmetry axes
+
+Ta=300;Tb=441;Tc=600;Td=300;Te=432;Tf=600;Tg=600;Th=600;Ti=300;Tj=384;Tk=461;Tl=485;Tm=490;Tn=300;To=340;Tp=372;Tq=387;Tr=391;Ts=300;Tt=300;Tu=300; Tv=300;Tw=300;
+// Above grid point temperatures are given in the question for the quarter section considered in degF(a,b,c...w are grid points)
+
+q1=4*k*((Tc-Tb)/2+(Tf-Te)+(Tf-Tk)+(Tg-Tl)+(Th-Tm)/2); // Amount of heat coming from inside in Btu/hr
+q2=4*k*((Tb-Ta)/2+(Te-Td)+(Tj-Ti)+(To-Tn)+(To-Tt)+(Tp-Tu)+(Tq-Tu)+(Tr-Tw)/2); // Amount of heat going outside in Btu/hr
+q=(q1+q2)/2; // average of heat going in and heat coming out
+printf("\n Total heat flow per unit depth is %.1fBtu/hr",q);
+
+S=q/(k*(Tc-Ta)); // shape factor in ft
+printf("\n Shape factor is %.2fft",S)
diff --git a/617/CH3/EX3.2/Example3_2.sci b/617/CH3/EX3.2/Example3_2.sci new file mode 100755 index 000000000..3673dcca4 --- /dev/null +++ b/617/CH3/EX3.2/Example3_2.sci @@ -0,0 +1,21 @@ +clear;
+clc();
+
+// To compute tempertures at the contact surfaces inside the furnaces
+
+x1=9/12; // thickness of firebrick in ft
+k1=0.72; // thermal conductivity of firebrick in Btu/hr-ft-degF
+x2=5/12; // thickness of insulating brick in ft
+k2=0.08; // thermal conductivity of insulating brick in Btu/hr-ft-degF
+x3=7.5/12; // thickness of redbrick in ft
+k3=0.5; // thermal conductivity of firebrick in Btu/hr-ft-degF
+t1=1500; // inner temperature of wall in degF
+t2=150; // outer temperature of wall in degF
+
+// resistances of mortar joints are neglected
+q=(t1-t2)/(x1/k1+x2/k2+x3/k3); // heat flow per square ft in Btu/hr
+t2=t1-(q*x1/k1); // first contact temperature in degF
+printf("\n The temperature at the contact of firebrick and insulating brick is %d degF",t2);
+
+t3=t2-(q*x2/k2); // second contact temperature in degF
+printf("\n The temperature at the contact of insulating brick and red brick is %d degF",t3);
\ No newline at end of file diff --git a/617/CH3/EX3.3/Example3_3.sci b/617/CH3/EX3.3/Example3_3.sci new file mode 100755 index 000000000..6c40083d0 --- /dev/null +++ b/617/CH3/EX3.3/Example3_3.sci @@ -0,0 +1,19 @@ +clear;
+clc();
+
+ // to calculate the heat loss from pipe
+
+ d1=2.375/12; // internal diameter of pipe in ft
+ t=1/12; // thickness of insulating material in ft
+ d2=d1+2*t; // external (insulation)diameter of pipe in ft
+ k=0.0375; // thermal conductivity of insulating material in Btu/hr-ft-F
+ l=30; // length of pipe in ft
+ t1=380; // inner surface temperature of insulation
+ t2=80; // outer surface temperature of insulation
+
+ q=2*%pi*k*(t1-t2)/log(d2/d1); // heat loss per unit length
+ printf("\n Heat loss per linear foot is %.d Btu/hr",q)
+
+ qtot=round(q)*l; // heat loss for 30 ft pipe
+ printf("\n Total heat loss through 30 ft of pipe is %d Btu/hr",qtot)
+
\ No newline at end of file diff --git a/617/CH3/EX3.4/Example3_4.sci b/617/CH3/EX3.4/Example3_4.sci new file mode 100755 index 000000000..4577fdada --- /dev/null +++ b/617/CH3/EX3.4/Example3_4.sci @@ -0,0 +1,17 @@ +clear;
+clc();
+
+// To calculate heat loss from pipe
+
+d1=10.75/12; // outer diameter of pipe in ft
+x1=1.5/12; // thickness of insulation 1 in ft
+x2=2/12; // thickness of insulation 2 in ft
+d2= d1+2*x1; // diameter of insulation 1 in ft
+d3=d2+2*x2; // diameter of insulation 1 in ft
+t1=700; // inner surface temperature of composite insulation in degF
+t2=110; // outer surface temperature of composite insulation in degF
+k1=0.05; //thermal conductivity of material 1 in Btu/hr-ft-degF
+k2=0.039; // thermal conductivity of material 2 in Btu/hr-ft-degF
+
+q=2*%pi*(t1-t2)/(log(d2/d1)/k1+log(d3/d2)/k2); // heat loss per linear foot in Btu/hr
+printf("\n The heat loss is found to be %d Btu/hr-ft", q);
\ No newline at end of file diff --git a/617/CH3/EX3.5/Example3_5.sci b/617/CH3/EX3.5/Example3_5.sci new file mode 100755 index 000000000..0805ef320 --- /dev/null +++ b/617/CH3/EX3.5/Example3_5.sci @@ -0,0 +1,13 @@ +clear;
+clc();
+
+// To find out heat loss through 1 sq. ft of flat slab of 85%magnesia and 15% asbestos
+
+km=0.0377; // Mean thermal conductivity at 220degF
+t1=260; // Inner surface temperature of slab in degF
+t2=180; // Outer surface temperature of slab in degF
+A=1; // Area of slab in ft
+x=2/12; // Thickness of insulation in ft
+
+q=km*A*(t1-t2)/x; // Heat loss through slab in Btu/hr
+printf("\n Heat loss through flat slab is %.1f Btu/hr",q);
diff --git a/617/CH3/EX3.6/Example3_6.sci b/617/CH3/EX3.6/Example3_6.sci new file mode 100755 index 000000000..f225ce8c2 --- /dev/null +++ b/617/CH3/EX3.6/Example3_6.sci @@ -0,0 +1,23 @@ +clear all
+clc()
+
+// To find out heat loss through conduction through a furnace
+k=0.8 // Avg. thermal conductivity in Btu/hr-ft-degF
+T1=400 // Inner surface temperature of furnace in degF
+T2=100 // Outer surface temperature of furnace in degF
+a=3 // Length of furnace in ft
+b=4 // Breadth of furnace in ft
+c=2.5 // Height of furnace in ft
+Aa=2*a*b // Area of surface A in ft^2
+Ab=2*b*c // Area of surface A in ft^2
+Ac=2*a*c // Area of surface A in ft^2
+x=4.5/12 // Thickness of insulation in ft
+t=24 // Time elapsed in hr
+M=4 // Number of edges
+N=8 // Number of corners
+
+S=Aa/x+Ab/x+Ac/x+0.54*(a+b+c)*M+0.15*x*N // Shape factor
+qo=S*k*(T1-T2) // Heat flow per hour
+q=qo*t // Heat loss in 24 hr
+
+printf("The heat loss in 24 hr is %d Btu",q)
\ No newline at end of file diff --git a/617/CH3/EX3.7/Example3_7.sci b/617/CH3/EX3.7/Example3_7.sci new file mode 100755 index 000000000..851fd9565 --- /dev/null +++ b/617/CH3/EX3.7/Example3_7.sci @@ -0,0 +1,13 @@ +clear;
+clc();
+
+// To compute shape factor for the special section in figure
+
+// Ratio of diameter of circle to the side of square is 0.5. Hence required lines have been estabilished by trial and error method.
+
+M=8*9; // number of flow channels for the entire section
+N=8.37; // number of equal channel intervals
+// the fractional part arises due to the fractional part of temperature close to border EG
+
+k = M/N; // Ratio of shape factor to wall length
+printf("\n Shape factor for the special section (where the ratio of radius of circle to half side length is 0.5),S is %.2fL", k );
diff --git a/617/CH3/EX3.8/Example3_8.sci b/617/CH3/EX3.8/Example3_8.sci new file mode 100755 index 000000000..931c74cf1 --- /dev/null +++ b/617/CH3/EX3.8/Example3_8.sci @@ -0,0 +1,21 @@ +clear;
+clc();
+
+// To find the temperature of planes indicated by grid points using relaxation method
+t1=800; // inner surface temperature of wall in degF
+t4=200; // outer surface temperature of wall in degF
+
+//Grids are square in shape so delx =dely where delx,y sre dimensions of square grid
+
+t2=[700 550 550 587.5 587.5 596.9 596.9 599.3 599.3 599.8]; // Assumed temperature of grid point 1
+t3=[300 300 375 375 393.8 393.8 398.5 398.5 399.6 399.6]; // Assumed temperature of grid point 2
+
+for i=1:9
+ th2(i)=t1+t3(i)-2*t2(i);; // th1= q/kz at grid pt1
+ th3(i)=t2(i)+t4-2*t3(i);// th2= q/kz at grid pt2
+ printf("\n Assuming t2=%.1f degF and t2=%.1f degF \n th1[%d]=%.1f degF and th2[%d]=%.1f degF \n",t2(i),t3(i),i,th2(i),i,th3(i));
+ printf(" Since th2[%d] is not equal to th3[%d], hence other values of t2 and t3 are to be assumed\n",i,i);
+end
+
+printf("\nAssuming t2=600 degF and t3=400 degF, th2=th3.");
+printf("\nHence Steady state condition is satisfied at grid temperatures of 400 degF and 600 degF");
diff --git a/617/CH4/EX4.1/Example4_1.sci b/617/CH4/EX4.1/Example4_1.sci new file mode 100755 index 000000000..c528ae3b5 --- /dev/null +++ b/617/CH4/EX4.1/Example4_1.sci @@ -0,0 +1,35 @@ +clc();
+clear;
+
+// To find heat changes and temperature change on heating of a concrete wall
+
+b=9; // Thickness of the wall in ft
+A=5; // Area of wall
+k=0.44; // Thermal conductivity in Btu/hr-ft-degF
+Cp=.202; // Specific heat in Btu/lbm-degF
+rho=136; // Density in lb/ft^3
+
+function[t]=templength(x); // Temperature function in terms of length
+ t = 90 - 80*x +16*x^2 +32*x^3 -25.6*x^4;
+ funcprot(0);
+endfunction
+tgo = derivative(templength,0); // Temperature gradient at x=0ft
+tgl = derivative(templength,9/12); // Temperature gradient at x=9/12ft
+
+qo = -k*A*tgo; // Heat entering per unit time in Btu/hr
+printf("Heat entering per unit time is %.2f Btu/hr \n",qo);
+ql = -k*A*tgl; // Heat coming out per unit time in Btu/hr
+printf(" Heat coming per unit time is %.2f Btu/hr \n",ql);
+q3 = qo-ql; //Heat energy stored in Btu/hr
+printf(" Heat energy stored in wall is %.2f Btu/hr \n",q3);
+
+a=k/(rho*Cp); // Thermal diffusivity
+function[t2]=doublederivative(y); // Derivative of tempearture with respect to length in degF/ft
+ t2= -80+32*y+96*y^2-102.4*y^3;
+ funcprot(0);
+endfunction
+timeder0=a*derivative(doublederivative,0); // derivative of temperature wrt time at x=0 in degF
+printf(" Time derivative of temperature wrt time at x=0ft is %.2f degF/hr\n",timeder0);
+timeder1=a*derivative(doublederivative,9/12); // derivative of temperature wrt time at x=9/12 in degF
+printf(" Time derivative of temperature wrt time at x=9/12ft is %.2f degF/hr\n",timeder1);
+
diff --git a/617/CH4/EX4.2/Example4_2.sci b/617/CH4/EX4.2/Example4_2.sci new file mode 100755 index 000000000..bdc8f46e2 --- /dev/null +++ b/617/CH4/EX4.2/Example4_2.sci @@ -0,0 +1,33 @@ +clc();
+clear;
+// To find heat changes and temperature change on heating of a concrete wall
+b=9; // thickness of the wall in ft
+A=5; // area of wall in ft^2
+k=0.44; // Thermal conductivity in Btu/hr-ft-degF
+Cp=.202; // Specific heat in Btu/lbm-degF
+rho=136; // density in lb/ft^3
+
+function[t]=templength(x);
+ t = 90 - 8*x-80*x^2;
+ funcprot(0);
+endfunction
+tgo = derivative(templength,0); // temperature gradient at x=0ft
+tgl = derivative(templength,9/12); // temperature gradient at x=9/12ft
+
+qo = -k*A*tgo; // Heat entering per unit time in Btu/hr
+printf("Heat entering per unit time is %.2f Btu/hr \n",qo);
+ql = -k*A*tgl; // Heat coming out per unit time in Btu/hr
+printf(" Heat coming per unit time is %.2f Btu/hr \n",ql);
+q3 = qo-ql; //Heat energy stored in Btu/hr
+printf(" Heat energy stored in wall is %.2f Btu/hr \n",q3);
+
+a=k/(rho*Cp); // Thermal diffusivity in ft^2/hr
+function[t2]=doublederivative(y); // derivative of tempearture with respect to length in degF/ft
+ t2= -8-160*x;
+ funcprot(0);
+endfunction;
+timeder0=a*derivative(doublederivative,0); // derivative of temperature wrt time at x=0 in degF
+printf(" Time derivative of temperature wrt time at x=0ft is %.2f degF/hr\n",timeder0);
+timeder1=a*derivative(doublederivative,9/12); // derivative of temperature wrt time at x=9/12 in degF
+printf(" Time derivative of temperature wrt time at x=9/12ft is %.2f degF/hr\n",timeder1);
+printf(" Teperature at each part of wall decreases equally");
diff --git a/617/CH4/EX4.3/Example4_3.sci b/617/CH4/EX4.3/Example4_3.sci new file mode 100755 index 000000000..bc85a2de5 --- /dev/null +++ b/617/CH4/EX4.3/Example4_3.sci @@ -0,0 +1,23 @@ +clc();
+clear;
+
+// To find the tempearure and heat low in case of sudden heat change
+
+t = 10; // time elapsed in hr
+Ti= 70; // tempearature of wall initially in degF
+Ts = 1500; // temperature of surface when suddenly changed in degF
+a = 0.03; // thermal diffusivity in ft^2/hr
+k = 0.5; // thermal conductivity in Btu/hr-ft-degF
+A = 10; // area of wall in sq ft
+x = 7/12; // distance from surface where tempearture is to be found in ft
+f = x/(2*sqrt(a*t));
+// From gaussian error function table erf can be found
+errorf = 0.55; // Referred from table
+
+T = Ts+(Ti-Ts)*errorf;
+printf("Temperaure at a distance of 7/12ft from surface is %.1f degF \n",T);
+q = -k*A*(Ti-Ts)*exp(-x^2/(4*a*t))/sqrt(t*%pi*a); // heat flow rate at a distance
+qtot = -k*A*(Ti-Ts)*2*sqrt(t/(%pi*a)); // total heat flowing after 10 hrs in Btu
+printf(" Heat flowing at a distance of 7/12 ft from surface is %d Btu/hr\n",q);
+printf(" Total heat flow after 10hrs is %f Btu",%pi);
+
diff --git a/617/CH4/EX4.4/Example4_4.sci b/617/CH4/EX4.4/Example4_4.sci new file mode 100755 index 000000000..539502ccf --- /dev/null +++ b/617/CH4/EX4.4/Example4_4.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+// To find the temperature at center of sphere on sudden temperature change
+d = 16/12; // Diameter of sphere in ft
+t = 20/60; // Time elapsed in hr
+a = 0.31; // thermal diffusivity of steel in ft^2/hr
+Ti = 80; // Temperature of steel sphere initially in degF
+Ts = 1200; // Temperature of surface suddenly changed in degF
+s = 4*a*t/d^2; // A parameter
+// From table the value of F(s) can be known
+Fs=0.20;
+Tc = Ts+(Ti-Ts)*Fs; // Tempearture at the center of sphere in degF
+printf("The tempearture at the center of steel sphere after 20 mins is %d degF",Tc);
\ No newline at end of file diff --git a/617/CH4/EX4.5/Example4_5.sci b/617/CH4/EX4.5/Example4_5.sci new file mode 100755 index 000000000..65a309602 --- /dev/null +++ b/617/CH4/EX4.5/Example4_5.sci @@ -0,0 +1,12 @@ +clc();
+clear;
+// To estimate the time lag of temperature (sine) wave
+t = 24; // Time period of tempearture wave in hr
+k = 0.6; // Thermal conductivity of wall in Btu/hr-ft-degF
+Cp = 0.2; // Specific heat capacity of wall in Btu/lb-degF
+y = 110; // specific gravity in lb/ft^3
+x = 8/12; // Distance from surface in ft
+a = k/(y*Cp); // Thermal diffusivity in ft^2/hr
+n=1/t; // frequency in /hr
+delr = x/(2*sqrt(a*%pi*n); // Time lag in hr
+printf("Time lag of the temperature at a point 8 in from surface is %.1f hr", delr;
diff --git a/617/CH4/EX4.6/Example4_6.sci b/617/CH4/EX4.6/Example4_6.sci new file mode 100755 index 000000000..55ce882fa --- /dev/null +++ b/617/CH4/EX4.6/Example4_6.sci @@ -0,0 +1,26 @@ +clc();
+clear;
+
+// To calculate the range in temperatures at different depths
+T1=-15; // Min temperature at surface in degF
+T2=25; // Max temperature at surface in degF
+t=24; // time gap in hrs
+k=1.3; // thermal conductivity in Btu/hr-ft-degF
+Cp=0.4; // heat capacity in lb/ft-degF
+y=126.1; // specific gravity in lb/ft^3
+n=1/t; // frequency in /hr
+Tm=(T1+T2)/2;
+a=k/(y*Cp); // thermal diffusivity in ft^2
+
+x1=2;
+x2=6;
+th0=(T1-T2)/2;
+th1=th0*-exp(-x1*sqrt(%pi*n/a)); // temperature range at 2 ft depth
+th2=th0*-exp(-x2*sqrt(%pi*n/a)); // temperature range at 6 ft depth
+printf("Amplitude of tempearture at 2ft deep is %.2f degF\n",th1);
+printf(" Amplitude of tempearture at 6ft deep is %.2f degF\n",th2);
+printf(" At a depth of 2ft , temperature varies from 4.78 degF to 5.22 degF and at a depth of 6 ft, temperature remains constant at 5 degF");
+delr1=x1/2*sqrt(1/(a*%pi*n)); // time lag at 2 ft depth
+delr2=x2/2*sqrt(1/(a*%pi*n)); // time lag at 6 ft depth
+printf(" Lag of temperature wave at a depth 2 ft is %.1f hr \n",delr1);
+printf(" Lag of temperature wave at a depth 6 ft is %.1f hr \n",delr2);
\ No newline at end of file diff --git a/617/CH4/EX4.7/Example4_7.sci b/617/CH4/EX4.7/Example4_7.sci new file mode 100755 index 000000000..b23f47eb2 --- /dev/null +++ b/617/CH4/EX4.7/Example4_7.sci @@ -0,0 +1,27 @@ +clc();
+clear;
+
+// To calculate the range in temoperatures at different depths
+T1=10; // Min temperature at surface in degF
+T2=-10; // Max temperature at surface in degF
+t1=24;
+t2=5; // Time gap in hrs
+k=0.3; // Thermal conductivity in Btu/hr-ft-degF
+Cp=0.47; // Heat capacity in lb/ft-degF
+y=100; // Specific gravity in lb/ft^3
+n1=1/t1; // Frequency in /hr
+Tm=(T1+T2)/2;a=k/(y*Cp); // thermal diffusivity in ft^2
+n=1/t1; // Frequency in /sec
+x1=1;
+x2=1; // Depth in ft
+th0=(T1-T2)/2;th1=th0*exp(-x1*sqrt(%pi*n/a)); // temperature range at 2 ft depth
+th2=th0*exp(-x2*sqrt(%pi*n/a)); // Temperature range at 6 ft depth
+printf("Amplitude of tempearture at 2ft deep is %.2f degF\n",th1);
+delr1=x1/2*sqrt(1/(a*%pi*n)); // Time lag at 2 ft depth
+printf(" Lag of temperature wave at a depth 2 ft is %.1f hr \n",delr1);
+ // To calculate the temperature at a depth of 1 ft , 5 hr after the srface temperature reaches the minimum temperature
+ r=3/(4*n); // Time at which minimum surface temperature occurs for the first time in hr
+ r1=r+5; // Time ar which temperature is to be found out in degF
+ th3=th0*exp(-x1*sqrt(%pi*n/a))*sin(2*%pi*r1/24-4.53);
+ Tr=Tm+th3; // Temperature to be found out in degF
+ printf(" The temperaure at 1 ft depth is %.2f degF \n",Tr);
\ No newline at end of file diff --git a/617/CH4/EX4.8/Example4_8.sci b/617/CH4/EX4.8/Example4_8.sci new file mode 100755 index 000000000..ad587580d --- /dev/null +++ b/617/CH4/EX4.8/Example4_8.sci @@ -0,0 +1,27 @@ +clc();
+clear;
+
+// to compute the temperatures at different points
+a=0.02; // thermal diffusivity in ft^2/hr
+M=4; // the value of 4 is selected for M
+x=9/12; // thickness of wall in ft
+delx=1.5/12;
+delr=delx^2/(a*M); // at time interval the heat transfeered will change the temperature of sink from tb2 to tb2o
+printf("The time interval is to be of %.3f hr \n",delr);
+
+t1o=370; t2o=435; t3o=480; t4o=485; t5o=440; t6o=360; t7o=250;
+
+// tempetaures at different positions at wall in degF initially
+// we know qo=Z*delx*dely*rho*Cp(tb2'-tb2)/delr So on solving equations we get tb2'=(tb1+tb3+ta2+tc2)/4
+// using above formula, temperaures at different positions as shown below can be calculated in degF
+
+ta=[370 430 470 473 431 352 250];
+tb=[370 425 461 462 422 346 250];
+tc=[370 420 452 452 413 341 250];
+td=[370 415 444 442 404 336 250];
+printf(" The temperatures at different positions 0.78 hr after, are as follows \n");
+for i=1:7
+printf(" The temperature at point %d is %d degF \n",i,td(i));
+end
+
+
diff --git a/617/CH4/EX4.9/Example4_9.sci b/617/CH4/EX4.9/Example4_9.sci new file mode 100755 index 000000000..8456fd2f8 --- /dev/null +++ b/617/CH4/EX4.9/Example4_9.sci @@ -0,0 +1,25 @@ +clc();
+clear;
+
+// to compute the temperatures at different points
+
+a=0.53; // thermal diffusivity in ft^2/hr
+M=4; // the value of 4 is selected for M
+x=6/12; // thickness of wall in ft
+delx=2/12;
+delr=delx^2/(a*M); // at time interval the heat transfeered will change the temperature of sink from tb2 to tb2o
+printf("the time interval is to be of %.3f hr \n",delr);
+
+// the temperature is constant in the whole wall initiallt 100 degF and afterwards it changes to 1000 degF.
+// we know qo=Z*delx*dely*rho*Cp(tb2'-tb2)/delr So on solving equations we get tb2'=(tb1+tb3+ta2+tc2)/4
+// Using above formula we can calculate the different temperatures as given below in degF
+
+ta=[100 550 775 888 944];
+tb=[100 550 775 888 944];
+tc=[100 550 775 888 944];
+td=[100 550 775 888 944];
+printf(" the temperatures at different positions 0.052 hr after, are as follows \n");
+printf(" the temperature at point a is %d degF \n",ta(5));
+printf(" the temperature at point a is %d degF \n",tb(5));
+printf(" the temperature at point a is %d degF \n",tc(5));
+printf(" the temperature at point a is %d degF \n",td(5));
\ No newline at end of file diff --git a/617/CH5/EX5.1/Example5_1.sci b/617/CH5/EX5.1/Example5_1.sci new file mode 100755 index 000000000..af2026b31 --- /dev/null +++ b/617/CH5/EX5.1/Example5_1.sci @@ -0,0 +1,19 @@ +clc();
+clear;
+
+// to calculate the maximum temperature inside the coil when current was 2.5 amp
+// the ratio of radii 12/13.5 is so great that the curvature may be neglected
+
+Di= 10/12; // inside diameter of the coil in ft
+x=7/48; // thickness of coil in ft
+ts=70.5; // Initial temp. of coil in degF
+Rm=12.1; // Resistance of coil
+e=0.0024; // Temperature coefficient of coil in degF
+i=0.009; // Initial current in amp
+V=0.1; // Initial Voltage in volts
+Rs=V/i; // Initial resistance in ohms
+Thm=(Rm/Rs-1)/e; // Mean temperature in degF
+Th0=1.5*Thm; // Increase in temperature in degF
+to=ts+Th0; // Maximum temperature in degF
+printf("The maximum temperature of the coil was %.1f degF",to);
+
diff --git a/617/CH5/EX5.2/Example5_2.sci b/617/CH5/EX5.2/Example5_2.sci new file mode 100755 index 000000000..94959c09a --- /dev/null +++ b/617/CH5/EX5.2/Example5_2.sci @@ -0,0 +1,21 @@ + clc();
+clear;
+
+// to find tempearture difference between inner and outer surface
+r=1/4; // radius in inches
+to=300; // outer surface temperature of cylinder in degF
+q0=10; // i2r heat loss in Btu-in^2/hr
+k=10; // thermal conductivity of the material in Btu/hr-ft-degF
+tc=to+(q0*r*r)*12 /(4*k); // temperature at center
+delt=tc-to;
+printf("The temperature diference between center and outer surface is %.2f degF",delt);
+
+// to find heat flow from outer surface
+
+// Total energy within the cylinder must be transferred to as heat to outer surface
+
+v=%pi*r^2; // Volume of heatinf element in in^3
+q1=q0*v; // heat flow to outer surface in Btu/sec
+tr=-q1*r/(2*k); // derivative of temperature wrt radius
+q=q1*12; // Heat flow at the outer surfae in Btu/hr-ft
+printf("\n Heat transfer per unit length at the outer surface is %.1f Btu/hr",q);
diff --git a/617/CH6/EX6.1/Example6_1.sci b/617/CH6/EX6.1/Example6_1.sci new file mode 100755 index 000000000..d41496ee5 --- /dev/null +++ b/617/CH6/EX6.1/Example6_1.sci @@ -0,0 +1,12 @@ +clc();
+clear;
+
+// To calculate the reynolds number
+
+u=2.08/32.2; // viscosity of water at 80degF in slug/ft-hr
+rho=62.4/32.2; // density of water in slug/ft^3
+d=2/12; // inner diameter of tube in ft
+v=10; // average water velocity in ft/sec
+Nre=d*v*rho*3600/u; // reynolds number
+// 3600 is multiplies to convert sec into hrs
+printf("Reynolds Number is %d",Nre);
\ No newline at end of file diff --git a/617/CH6/EX6.2/Example6_2.sci b/617/CH6/EX6.2/Example6_2.sci new file mode 100755 index 000000000..306cc7e0d --- /dev/null +++ b/617/CH6/EX6.2/Example6_2.sci @@ -0,0 +1,12 @@ +clc();
+clear;
+
+// To calculate the reynolds number
+
+u=2.08/32.16; // viscosity of water at 80 degF in slug/ft-hr
+m=965000/32.16; // mass velocity of water in slug/hr-ft
+d=1/12; // inner diameter of tube in ft
+Nre=m*d/u; // reynolds number
+
+// 3600 is multiplies to convert sec into hrs
+printf("Reynolds Number is %d",Nre);
\ No newline at end of file diff --git a/617/CH7/EX7.1/Example7_1.sci b/617/CH7/EX7.1/Example7_1.sci new file mode 100755 index 000000000..0bc06f0c5 --- /dev/null +++ b/617/CH7/EX7.1/Example7_1.sci @@ -0,0 +1,17 @@ +clc();
+clear;
+
+// To find the film coefficient for free convetion for a heated plate
+
+tp=200; // Temperature of heated plate in degF
+ta=60; // Temperature of air in degF
+tf=(tp+ta)/2; // Temperature of film in degF
+delt=tp-ta; // Temperature difference in degF
+Z=950000; // As referred from the chart for corresponding temperature
+L=18/12; // Height of vertical plate in ft
+
+X=L^3*(delt)*Z;
+// This value shows that it is laminar range so formula is as follows
+
+h=0.29*(delt/L)^.25; // Heat transfer coeeficient in Btu/hr-ft^2-degF
+printf("The film coefficient for free convetion for the heated plate is %.1f Btu/hr-ft^2/degF",h)
\ No newline at end of file diff --git a/617/CH7/EX7.2/Example7_2.sci b/617/CH7/EX7.2/Example7_2.sci new file mode 100755 index 000000000..cad4deccc --- /dev/null +++ b/617/CH7/EX7.2/Example7_2.sci @@ -0,0 +1,20 @@ +clc();
+clear;
+
+// To find the film coefficient for natural convetion for a heated square plate
+
+tp=300; // Temperature of heated plate in degF
+ta=80; // Temperature of air in degF
+tf=(tp+ta)/2; // Temperature of film in degF
+delt=tp-ta; // Temperature difference in degF
+Z=610000; // As referred from the chart for corresponding temperature
+L=7/12; // Height of vertical plate in ft
+A=L*L; // Area of square plate in ft^2
+X=L^3*(delt)*Z;
+
+// This value shows that it is turbulent range , so formula for heat transfer coefficient is as follow
+h=0.22*delt^(1/3); // Temperature coeeficient in Btu/hr-ft^2-degF
+q=h*A*delt; // Heat loss in Btu/hr
+
+printf("The film coefficient for free convetion for the heated plate is %.2f Btu/hr-ft^2-degF",h);
+printf("\n The heat loss by natural convection from the square plate is %.2f Btu/hr",q);
diff --git a/617/CH7/EX7.3/Example7_3.sci b/617/CH7/EX7.3/Example7_3.sci new file mode 100755 index 000000000..8c5f2b0e9 --- /dev/null +++ b/617/CH7/EX7.3/Example7_3.sci @@ -0,0 +1,29 @@ +clc();
+clear;
+// To calculate heat loss by natural convection in a horizontal nominal steam pipe
+
+D=0.375; // Outer diameter in ft
+T1=200; // Pipe surface temperature in degF
+T2=70; // Air temperature in degF
+Tf=(T1+T2)/2; // Film temperature at whih physical properties is to be measured
+delT=T1-T2;
+rho=0.0667/32.2; // Density in slug/ft^3
+u=0.0482/32.2; // Viscosity in slug/ft-hr
+b=1/(460+T2 );
+Cp=0.241*32.2; // Heat capacity in Btu/slug-ft
+// The value of specific heat is related to 1 lb mass so it must be multiplied to 32.2 to convert it into slugs
+k=0.0164; // Thermal conductivity in Btu/hr-ft-degF
+g=32.2*3600;
+// Unit of time used is hour so it must be converted to sec. Hence 3600 is multiplied
+Ngr=D^3*rho^2*b*g*delT/(u^3); // Grasshops number
+Npr=u*Cp/k; // Prandtls number
+A=log(Ngr*Npr);
+
+// Tha value of A is 6.866
+// Now seeing the value of nusselt number from the table
+
+Nnu=25.2; // Nusselt number
+h=Nnu*k/D; // Heat transfer coefficient
+q=h*delT; // Heat loss per unit area in Btu/hr
+
+printf("Heat loss per unit square foot is %d Btu/hr-ft^2",q);
diff --git a/617/CH7/EX7.4/Example7_4.sci b/617/CH7/EX7.4/Example7_4.sci new file mode 100755 index 000000000..056799dab --- /dev/null +++ b/617/CH7/EX7.4/Example7_4.sci @@ -0,0 +1,19 @@ +clc();
+clear;
+
+// To find the film coefficient for natural convetion for a heated square plate
+
+tp=200; // Temperature of heated plate in degF
+ta=70; // Temperature of air in degF
+tf=(tp+ta)/2; // Temperature of film in degF
+delt=tp-ta; // Temperature difference in degF
+Z=910000; // As referred from the chart for corresponding temperature
+D=4.5/12; // Diameter of pipe in ft
+X=D^3*(delt)*Z;
+// This value lies between X=1000 to X=10^9 , so formula for heat transfer coefficient is as follow
+
+h=0.27*(delt/D)^(1/4); // Temperature coeeficient in Btu/hr-ft^2-degF
+q=h*delt; // Heat loss in Btu/hr
+
+printf("The film coefficient for free convetion for the heated plate is %.2f Btu/hr-ft^2-degF",h);
+printf("\n The heat loss by natural convection from the square plateis %d Btu/hr",q);
diff --git a/617/CH8/EX8.1/Example8_1.sci b/617/CH8/EX8.1/Example8_1.sci new file mode 100755 index 000000000..29e330821 --- /dev/null +++ b/617/CH8/EX8.1/Example8_1.sci @@ -0,0 +1,21 @@ +clc();
+clear;
+
+// To calculate the average film coefficient of heat transfer
+
+D=0.0752; // Outer diameter in ft
+T1=61.4; // Pipe surface temperature in degF
+T2=69.9; // Air temperature in degF
+Tf=(T1+T2)/2; // Film temperature at whih physical properties is to be measured
+delT=T1-T2;
+rho=1.94; // Density in slug/ft^3 , 62.3/32.2
+u=0.0780; // viscosity in slug/ft-hr , 2.51/32.2
+Cp=1*32.2; // heat capacity in Btu/slug-ft
+k=0.340; // thermal conductivity in Btu/hr-ft-degF
+v=7*3600; // velocity in ft/sec
+
+Nre=D*v*rho/u; // Reynolds number
+Npr=u*Cp/k; // Prandtls number
+Nnu=0.023*Nre^.8*Npr^.4;
+h=Nnu*k/D; // heat transfer coefficient
+printf("The average film coefficient of heat transfer is %.d Btu/hr-ft^2-degF",h);
\ No newline at end of file diff --git a/617/CH8/EX8.3/Example8_3.sci b/617/CH8/EX8.3/Example8_3.sci new file mode 100755 index 000000000..2162eaa56 --- /dev/null +++ b/617/CH8/EX8.3/Example8_3.sci @@ -0,0 +1,15 @@ +clc();
+clear;
+
+// To calculate heat transfer coeeficient fir air flowing over a pipe
+
+D=1/12; // Inner diameter of pipe in ft
+k=0.0174; // Thermal conductivity in btu/hr-ft-degF
+Nre=8000; // Reynolds number
+
+// From table we can find out nusselt number
+Nnu=0.3*Nre^0.57; // Nusselt number
+h=round(Nnu)*k/D; // Heat transfer coefficient in btu/hr-ft^2-degF
+
+printf("heat transfer coefficient for air flowing is %.1f Btu/hr-ft^2-degF",h);
+
diff --git a/617/CH9/EX9.1/Example9_1.sci b/617/CH9/EX9.1/Example9_1.sci new file mode 100755 index 000000000..ab297d0df --- /dev/null +++ b/617/CH9/EX9.1/Example9_1.sci @@ -0,0 +1,34 @@ +clc();
+clear;
+
+// To find the temperature at the free end is made of copper iron and glass
+
+D = 3/48; // diameter in ft
+L = 9/12; // Length of steam vessel in ft
+T1 = 210; // Vessel temperature in degF
+T2 = 80; // Air temperature in degF
+th0 = T1-T2; // Temperature difference in degF
+h = 1.44; // Assumed heat coefficient in Btu/hr-ft^2-degF
+C = %pi*D; // Circumference of vessel in ft
+A = %pi*D*D/4; // Area of vessel in ft^2
+
+// For copper
+k1 = 219; // Heat conductivity of copper in Btu/hr-ft-degF
+m1 = sqrt(h*C/(k1*A)); // in /ft
+th1 = th0*2/(exp(m1*L)+exp(-m1*L));
+Tl1 = round(th1+T2); // The temperaure at the free end in degF
+printf("Temperature at free end of the copper rod is %d degF \n",Tl1);
+
+// For iron
+k2 = 36; // heat conductivity of copper in Btu/hr-ft-degF
+m2 = sqrt(h*C/(k2*A)); // in /ft
+th2 = th0*2/(exp(m2*L)+exp(-m2*L));
+Tl2 = th2+T2; // The temperaure at the free end in degF
+printf(" Temperature at free end of the iron rod is %.2f degF \n",Tl2);
+
+// For glass
+k3 = 0.64; // Heat conductivity of copper in Btu/hr-ft-degF
+m3 = sqrt(h*C/(k3*A)); // in /ft
+th3 = th0*2/(exp(m3*L)+exp(-m3*L));
+Tl3 = th3+T2; // The temperaure at the free end in degF
+printf(" Temperature at free end of the glass rod is %.2f degF \n",Tl3);
diff --git a/617/CH9/EX9.10/Example9_10.sci b/617/CH9/EX9.10/Example9_10.sci new file mode 100755 index 000000000..7713dbf7b --- /dev/null +++ b/617/CH9/EX9.10/Example9_10.sci @@ -0,0 +1,27 @@ +clc();
+clear;
+
+// To calculate the terminal temperature of oil and water
+
+To1=160; // inlet temperature of oil in degF
+Cpo=0.5; // Specific heat capacity in Btu/lb-degf
+Tw1=60; // Inlet temperature of water in degF
+mo=1000; // Mass flow rate of oil in lb/hr
+mw=2500; // Mass flow rate of water in lb/hr
+Cpw=1; // Heat capacity of water in Btu/hr
+X=mo*Cpo/(mw*Cpw); // Ratio of flow rates
+UA=1.15*mo*Cpo;
+B=UA/mo*Cpo;
+
+// from the graph, we can locate the point of A and B And corresponding effectiveness ratio
+E=0.86; // Effectiveness ratio
+To2=To1-E*(To1-Tw1); // Outlet temperature of oil in degF
+printf("The outlet temperature of oil is %d degF \n",To2);
+
+q=mo*Cpo*(To1-To2); // Heat transferred in Btu/hr
+Tw2=Tw1+(q/(mw*Cpw)); // Outlet temperature of oil in degF
+printf(" The outlet tempearture of water is %.1f degF",Tw2);
+
+
+
+
\ No newline at end of file diff --git a/617/CH9/EX9.11/Example9_11.sci b/617/CH9/EX9.11/Example9_11.sci new file mode 100755 index 000000000..c249ecca3 --- /dev/null +++ b/617/CH9/EX9.11/Example9_11.sci @@ -0,0 +1,22 @@ +clc();
+clear;
+
+// To compute the temprature distribution
+h=1; // Heat transfer coefficient in Btu/hr-ft^2-degF
+x=1; // Assumed thickness in ft
+k=1; // Thermal conductivity in Btu/hr-ft-degF
+N=h*x/k;
+t0=600;
+t4=200;
+t1=[500 550 550 525 525 512.5 512.5 512.5 506.2 506.2 506.2 506.2 503.1 503.1];
+t2=[450 450 450 450 425 425 425 412.5 412.5 412.5 406.3 406.3 406.3 403.1];
+t3=[350 350 325 325 325 325 312.5 312.5 312.5 306.3 306.3 303.1 303.1 303.1];
+
+// Assumed temperatures in degF for points 1 2 & 3 respectively
+for i=1:14
+th1(i)=t0+t2(i)-2*t1(i);
+th2(i)=t1(i)+t3(i)-2*t2(i);
+th3(i)=t2(i)+t4-2*t3(i);
+printf("Assuming t1=%.1f degF t2=%.1fdegF t3=%.1fdegF \n th1=%.1fdegF th2=%.1fdegF th3=%.1fdegF \n \n",t1(i),t2(i),t3(i),th1(i),th2(i),th3(i));
+end
+printf("This way assumption must be continued till all sink strengths are zero");
\ No newline at end of file diff --git a/617/CH9/EX9.2/Example9_2.sci b/617/CH9/EX9.2/Example9_2.sci new file mode 100755 index 000000000..3cb9cf925 --- /dev/null +++ b/617/CH9/EX9.2/Example9_2.sci @@ -0,0 +1,21 @@ +clc();
+clear;
+
+// To find the temperature at the free end is made of copper iron and glass
+
+D = 3/48; // diameter in ft
+L = 9/12; // Length of steam vessel in ft
+T1 = 210; // Vessel temperature in degF
+T2 = 80; // Air temperature in degF
+th0 = T1-T2; // Temperature difference in degF
+h = 1.44; // Assumed heat coefficient in Btu/hr-ft^2-degF
+C = %pi*D; // Circumference of vessel in ft
+A = %pi*D*D/4; // Area of vessel in ft^2
+
+k = 36; // heat conductivity of copper in Btu/hr-ft-degF
+m = sqrt(h*C/(k*A)); // in /ft
+q=k*A*m*th0*(exp(m*L)-exp(-m*L))/(exp(m*L)+exp(-m*L));
+// Heat loss by iron rod in Btu/hr
+printf("The rate of heat loss by iron rod is %.d Btu/hr",q);
+
+
diff --git a/617/CH9/EX9.3/Example9_3.sci b/617/CH9/EX9.3/Example9_3.sci new file mode 100755 index 000000000..0d5bf2c16 --- /dev/null +++ b/617/CH9/EX9.3/Example9_3.sci @@ -0,0 +1,11 @@ +clc();
+clear;
+
+// To calculate the heat transfer coefficient
+
+x = 3/96; // Thickness of plate in ft
+k = 220; // thermal conductivity in Btu/hr-ft-degF
+h1 = 480; // Inner film coefficient in Btu/hr-ft^2-degF
+h2 = 1250; // Outer film coefficient in Btu/hr-ft^2-degF
+U = 1/((1/h1)+(x/k)+(1/h2)); // Overall heat transer coeeficient in Btu-hr-ft^2-degF
+printf("Overall heat transfer coefficient is %d Btu/hr-ft^2-degF",U);
\ No newline at end of file diff --git a/617/CH9/EX9.4/Example9_4.sci b/617/CH9/EX9.4/Example9_4.sci new file mode 100755 index 000000000..5d93ead76 --- /dev/null +++ b/617/CH9/EX9.4/Example9_4.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To calculate the overall heat transfer coefficient
+
+r2 = 3/96; // Outer radius in ft
+x = 0.1/12; // Thickness of plate in ft
+r1 = r2-x; // Outer radius in ft
+k = 200; // thermal conductivity in Btu/hr-ft-degF
+h1 = 280; // Inner film coefficient in Btu/hr-ft^2-degF
+h2 = 2000; // Outer film coefficient in Btu/hr-ft^2-degF
+U = 1/((r2/(h1*r1))+(r2*log(r2/r1)/k)+(1/h2)); // Overall heat transer coeeficient in Btu-hr-ft^2-degF
+printf("Overall heat transfer coefficient is %d Btu/hr-ft^2-degF",U);
\ No newline at end of file diff --git a/617/CH9/EX9.5/Example9_5.sci b/617/CH9/EX9.5/Example9_5.sci new file mode 100755 index 000000000..8e9341516 --- /dev/null +++ b/617/CH9/EX9.5/Example9_5.sci @@ -0,0 +1,13 @@ +clc();
+clear;
+
+// To calculate LMTD for heat exchanger
+
+Tc1 = 120; // Inlet cold fluid temperature in degF
+Tc2 = 310; // Outlet cold fluid temperature in degF
+Th1 = 500; // Inlet hot fluid temperature in degF
+Th2 = 400; // Outlet hot fluid temperature in degF
+delt1 = Th2-Tc1; // Maximum temperature difference in degF
+delt2 = Th1-Tc2; // Minimum temperature difference in degF
+LMTD = (delt1-delt2)/log(delt1/delt2); // Log mean temperature difference
+printf("The log mean temperature difference is %d degF",LMTD)
diff --git a/617/CH9/EX9.6/Example9_6.sci b/617/CH9/EX9.6/Example9_6.sci new file mode 100755 index 000000000..c5e9b521a --- /dev/null +++ b/617/CH9/EX9.6/Example9_6.sci @@ -0,0 +1,17 @@ +clc();
+clear;
+
+// To calculate temperature difference for heat exchanger
+
+Tc1 = 120; // Inlet cold fluid temperature in degF
+Tc2 = 310; // Outlet cold fluid temperature in degF
+Th1 = 500; // Inlet hot fluid temperature in degF
+Th2 = 400; // Outlet hot fluid temperature in degF
+K = (Tc2-Tc1)/(Th2-Tc2); // Temperature ratio
+R = (Th1-Th2)/(Tc2-Tc1); // Temperature ratio
+delt1 = Th2-Tc1; // Maximum temperature difference in degF
+delt2 = Th1-Tc2; // Minimum temperature difference in degF
+LMTD = (delt1-delt2)/log(delt1/delt2); // Log mean temperature difference
+f = 0.99; // Correction factor as seen from figure
+LMTDc = round(LMTD*f); // Corrected log mean temperature difference
+printf("Log mean temperature difference is %d degF",LMTDc);
\ No newline at end of file diff --git a/617/CH9/EX9.7/Example9_7.sci b/617/CH9/EX9.7/Example9_7.sci new file mode 100755 index 000000000..800473333 --- /dev/null +++ b/617/CH9/EX9.7/Example9_7.sci @@ -0,0 +1,22 @@ +clc();
+clear;
+// To calculate the outside tube area for a single-pass steam condenser
+
+Do=1/12; // Outside diameter of the condenser in ft
+Di=0.902/12; // Outside diameter of the condenser in ft
+Ts=81.7; // Steam temperature in degF
+Tw1=61.4; // Water inlet temperature in degF
+Tw2=69.9; // Water outlet temperature in degF
+k=63; // Thermal conductivity in Btu/hr-ft-degF
+v=7; // average velocity in ft/sec
+h1=1270; // water side film coefficient i Btu/hr-ft^2-degF
+h2=1000; // Steam side film coefficient in Btu/hr-ft^2-degF
+
+U=1/((Do/(Di*h1))+(Do*log(Do/Di)/(2*k))+(1/h2)); // Heat transfer coefficient
+LMTD=((Ts-Tw1)-(Ts-Tw2))/log((Ts-Tw1)/(Ts-Tw2)); // Log mean temperature diff.
+m=731300; // Saturated steam to be handled in lb/hr
+L=1097.4-49.7; // Change in enthalpy in Btu/lb
+q=m*L; // Heat required in Btu/hr
+A=q/(U*LMTD); // Area of condenser in ft^2
+printf("The area of steam condenser is %d ft^2",A);
+
diff --git a/617/CH9/EX9.8/Example9_8.sci b/617/CH9/EX9.8/Example9_8.sci new file mode 100755 index 000000000..3d9d73c4c --- /dev/null +++ b/617/CH9/EX9.8/Example9_8.sci @@ -0,0 +1,53 @@ +clc();
+clear;
+
+// To calculate overall heat transfer coefficient for heat exchanger
+
+Tc1 = 139.7; // Inlet cold fluid temperature in degF
+Tc2 = 59.5; // Outlet cold fluid temperature in degF
+Th1 = 108.7; // Inlet hot fluid temperature in degF
+Th2 = 97.2; // Outlet hot fluid temperature in degF
+delt1 = Tc1-Th2; // Maximum temperature difference in degF
+delt2 = Th1-Tc2; // Minimum temperature difference in degF
+LMTD = round((delt1-delt2)/log(delt1/delt2));
+printf(" \n The log mean temperature difference is %d degF",LMTD);
+
+m = 18210; // Flow rate through tubes
+q = m*(Th2-Tc2); // Heat loss in Btu/hr
+A = 48.1; // Area in ft^2
+U = q/(A*LMTD); // Overall heat transfer coefficient
+printf(" \n The overall heat transfer coefficient is %d Btu/hr-ft^2-degF \n",U);
+
+
+// To calcalute using equations estabilished by correlation
+Ts = 113; // Average tube temperature in degF
+Tf = (123.9+Ts)/2; // Film temperature in degF
+// At this temperature thermal properties are considered
+p1 = 61.7/32.2; // Density in slug/ft^3
+u1 = 1.38/32.2; // Viscosity in slug/ft-hr
+Cp1 = 1*32.2; // Btu/slug/ft
+k1 = 0.366; // Thermal conductivity in Btu/hr-ft-degF
+D1 = 0.375/12; // Diameter in ft
+v1 = 7610; // Velocity in ft/sec
+Nre1 = v1*D1*p1/u1; // Reynolds number
+Npr1 = u1*Cp1/k1; // Prandtls number
+Nnu1 = 0.33*Nre1^0.6*Npr1^(1/3); // Nusselt number
+h1 = Nnu1*k1/D1; // Heat transfer coefficient
+printf(" \n The outer heat transfer coefficient is %d Btu/hr-ft^2-degF ",h1);
+
+// Taking the thermal properties at 78.3 degF
+p2 = 62.2/32.2; // Density in slug/ft^3
+u2 = 2.13/32.2; // Viscosity in slug/ft-hr
+Cp2 = 1*32.2; // Heat capacity in Btu/slug/ft
+k2 = 0.348; // Thermal conductivity in Btu/hr-ft-degF
+D2 = 0.277/12; // Diameter in ft
+v2 = 7140; // Velocity in ft/sec
+Nre2 = v2*D2*p2/u2; // Reynolds number
+Npr2 = u2*Cp2/k2; // Prandtls number
+Nnu2 = 0.023*Nre2^0.8*Npr2^(0.4); // Nusselt number
+h2 = Nnu2*k2/D2; // Heat transfer coefficient
+printf(" \n The inner heat transfer coefficient is %d Btu/hr-ft^2-degF",h2);
+
+k3 = 58;
+U1 = 1/((D1/(D2*h2))+(D1*log(D1/D2)/(2*k3))+(1/h1)); // Heat transfer coefficient
+printf(" \n The overall heat transfer coefficient accordind to estabilished correlation is %d Btu/hr-ft^2-degF \n",U1);
\ No newline at end of file diff --git a/617/CH9/EX9.9/Example9_9.sci b/617/CH9/EX9.9/Example9_9.sci new file mode 100755 index 000000000..8e3f36ba8 --- /dev/null +++ b/617/CH9/EX9.9/Example9_9.sci @@ -0,0 +1,19 @@ +clc();
+clear;
+
+// To determine the value of product of overall heat transfer and the total area
+
+To1=140; // inlet temperature of oil in degF
+To2=90; // Outlet temperature of oil in degf
+Cpo=0.5; // Specific heat capacity in Btu/lb-degf
+Tw1=60; // Inlet tempearture of water in degF
+Tw2=80; // Outlet temperature of water in degF
+mo=2000; // Mass flow rate of oil in lb/hr
+q=mo*Cpo*(To1-To2); // Heat transferred in Btu/hr
+Cpw=1; // Heat capacity of water in Btu/hr
+mw=q/(Cpw*(Tw2-Tw1)); // Mass flow rate in lb/hr
+E1=(Tw1-Tw2)/(Tw1-To2); // Effective ratio
+
+// Seeing the effective ratio and mass flow rate ratio, from the graph we get UA
+UA=1.15*mo*Cpo;
+printf("The product of overall heat transfer and total area is %d Btu/hr-degF",UA);
diff --git a/617/CH9/EX9.9b/Example9_9b.sci b/617/CH9/EX9.9b/Example9_9b.sci new file mode 100755 index 000000000..2918fb05d --- /dev/null +++ b/617/CH9/EX9.9b/Example9_9b.sci @@ -0,0 +1,26 @@ +clc();
+clear;
+
+// To calculate the temperature of surface and centre plane
+
+t=2; // Thickness of wall in ft
+To=100; // Initial temperature of wall in degF
+Tg=1000; // Temperature of hot gases exposed in degF
+k=8; // Thermal conductivity in Btu/hr-ft-degF
+p=162; // density in lb/ft^-3
+Cp=0.3; // Heat capacity in Btu/lb-degF
+h=1.6; // Heat transfer coefficient in Btu/hr-ft^-2-degF
+a=k/(p*Cp); // Thermal diffusivity
+
+// Considering the values of a and 4at/L^2 and hl/2k, the value of Phis, Phic and Si can be obtained
+Phis=0.37;
+Phic=0.41;
+Si=0.62;
+
+Ta=Tg+(To-Tg)*Phis; // Temperature of surface in degF
+printf("The temperature of surface is %d degF \n ",Ta);
+Tc=Tg+(To-Tg)*Phic; // Temperature of center plane in degF
+printf("The temperature of surface is %d degF \n ",Tc);
+A=10; // area of wall through which heat is absorbed
+q=p*Cp*t*A*Si*(To-Tg); // Heat absorbed in Btu/hr
+printf("The heat absorbed by wall is %d Btu",q);
\ No newline at end of file |