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 /1919/CH9 | |
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 '1919/CH9')
-rwxr-xr-x | 1919/CH9/EX9.1/Ex9_1.sce | 31 | ||||
-rwxr-xr-x | 1919/CH9/EX9.10/Ex9_10.sce | 39 | ||||
-rwxr-xr-x | 1919/CH9/EX9.11/Ex9_11.sce | 41 | ||||
-rwxr-xr-x | 1919/CH9/EX9.12/Ex9_12.sce | 35 | ||||
-rwxr-xr-x | 1919/CH9/EX9.13/Ex9_13.sce | 51 | ||||
-rwxr-xr-x | 1919/CH9/EX9.2/Ex9_2.sce | 35 | ||||
-rwxr-xr-x | 1919/CH9/EX9.3/Ex9_3.sce | 30 | ||||
-rwxr-xr-x | 1919/CH9/EX9.4/Ex9_4.sce | 42 | ||||
-rwxr-xr-x | 1919/CH9/EX9.5/Ex9_5.sce | 48 | ||||
-rwxr-xr-x | 1919/CH9/EX9.6/Ex9_6.sce | 34 | ||||
-rwxr-xr-x | 1919/CH9/EX9.7/Ex9_7.sce | 43 | ||||
-rwxr-xr-x | 1919/CH9/EX9.8/Ex9_8.sce | 48 | ||||
-rwxr-xr-x | 1919/CH9/EX9.9/Ex9_9.sce | 38 |
13 files changed, 515 insertions, 0 deletions
diff --git a/1919/CH9/EX9.1/Ex9_1.sce b/1919/CH9/EX9.1/Ex9_1.sce new file mode 100755 index 000000000..80246982b --- /dev/null +++ b/1919/CH9/EX9.1/Ex9_1.sce @@ -0,0 +1,31 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 1
+
+clear ;clc;
+
+//Given data
+X1 = 0.3 // volume fraction of N2
+X2 = 0.5 // volume fraction of He
+X3 = 0.2 // volume fraction of CO2
+m = 3000 // mass flowrate of oil in kg/hr
+Cp = 1.2 // molar heat capacity of oil in kJ/mol
+T1_o = 523.15 // entering temperature of oil in K
+T2_o = 323.15 // leaving temperature of oil in K
+T1_g = 303.15 // entering temperature of oil in K
+T2_g = 323.15 // leaving temperature of oil in K
+Cp1 = 29.1783 // molar heat capacity of N2 in kJ/mol
+Cp2 = 20.7860 // molar heat capacity of He in kJ/mol
+Cp3 = 37.1444 // molar heat capacity of CO2 in kJ/mol
+
+// Calculations
+Cp_m = X1*Cp1 + X2*Cp2 + X3*Cp3 // molar heat capacity of gas mixture
+
+N = m*Cp*(T1_o-T2_o)/(Cp_m*(T2_g-T1_g))
+
+
+// Output Results
+mprintf('Flow rate of gas mixture to cool oil = %4.3f kmol/h' ,N);
+
diff --git a/1919/CH9/EX9.10/Ex9_10.sce b/1919/CH9/EX9.10/Ex9_10.sce new file mode 100755 index 000000000..96c962470 --- /dev/null +++ b/1919/CH9/EX9.10/Ex9_10.sce @@ -0,0 +1,39 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 10
+
+clear ;clc;
+
+//Given data
+RH = 0.6 // relative humidity moist air
+T1 = 313.15 // Temp of air entering cooling device in K
+T2 = 293.15 // temperature at air required to leave in K
+P = 101.325 // pressure of entering air in kPa
+V = 300 // volumatric flow rate of air in m^3/min
+M = 28.97 // molecular weight of air
+R = 8.314 // gas constant
+
+// data from psychometric chart
+SH1 = 0.0284 // in kg H2O/kg air
+pw1 = 4.4 // in kPa
+h1 = 115 // in kJ/kg air
+SH2 = 0.0148 // in kg H2O/kg air
+h2 = 58 // in kJ/kg air
+hw3 = 83.95 // in kJ/kg at T = 20`C
+
+// at TDB = 40 `C; RH = 1
+ma1 = (101.325-pw1)*1e3*V*M/(R*1e3*T1)
+
+// masss balance for H2O: ma1*SH1 = ma2*SH2 + mw3
+mw3 = ma1*(SH1-SH2) // amount of water condensed in kg/min
+
+// Energy balance: ma1*h1 = ma2*h2 + mw3*hw3 + Qc
+Qc = ma1*(h1-h2) - mw3*hw3 // in kJ/min
+Qc = Qc*1e-3/60 // units conversion kJ/min to MW
+
+
+// Output Results
+mprintf('The amount of water condensed = %4.1f kg/min' , mw3);
+mprintf('\n The rate of cooling required = %4.1f MW' , Qc);
diff --git a/1919/CH9/EX9.11/Ex9_11.sce b/1919/CH9/EX9.11/Ex9_11.sce new file mode 100755 index 000000000..0ecc3d561 --- /dev/null +++ b/1919/CH9/EX9.11/Ex9_11.sce @@ -0,0 +1,41 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 11
+
+clear ;clc;
+
+//Given data
+RH1 = 0.8 // relative humidity moist air entering
+T1 = 308.15 // Temp of air entering cooling device in K
+P = 101.325 // pressure of entering air in kPa
+RH4 = 0.4 // relative humidity moist air leaving
+T4 = 293.15 // temperature at air required to leave in K
+m = 2 // flowrate dry air in kg/s
+
+
+// data from psychometric chart
+SH1 = 0.029 // in kg H2O/kg air
+h1 = 110 // in kJ/kg air
+SH4 = 0.0055 // in kg H2O/kg air
+h4 = 34 // in kJ/kg air
+SH2 = SH4
+RH2 = 1
+h2 = 19 // in kJ/kg air
+T2 = 278.15 // in K
+hw3 = 20.97 // at 5 degree C in kJ/kg
+
+// masss balance for H2O: ma1*SH1 = ma2*SH2 + mw3
+mw3 = m*(SH1-SH2) // amount of water condensed in kg/s
+
+// Energy balance: ma1*h1 = ma2*h2 + mw3*hw3 + Qc
+Qc = m*(h1-h2) - mw3*hw3 // in kJ/s
+
+Qh = m*(h4-h2)
+
+
+// Output Results
+mprintf('The amount of water condensed in refrigeration unit = %4.3f kg/s' , mw3);
+mprintf('\n The rate of cooling required in refrigeration unit = %2.0f kW' , Qc);
+mprintf('\n The rate of heating required in refrigeration unit = %2.0f kW' , Qh);
diff --git a/1919/CH9/EX9.12/Ex9_12.sce b/1919/CH9/EX9.12/Ex9_12.sce new file mode 100755 index 000000000..f73e3cdc3 --- /dev/null +++ b/1919/CH9/EX9.12/Ex9_12.sce @@ -0,0 +1,35 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 12
+
+clear ;clc;
+
+//Given data
+RH1 = 0.3 // relative humidity of summer day atmospheric air
+T1 = 313.15 // Temperature of air in summer day in K
+V = 3 // evaporative cooler rate in m^3/s
+t = 10 // cooler operation time in hours
+M = 28.97 // molecular weight of air
+R = 8.314 // gas constant
+
+// data from psychometric chart for T = 40`C and RH = 0.3
+SH1 = 0.0135 // in kg H2O/kg air
+pw1 = 2.05 // in kPa
+// Follow the constant wet bulb temperature line(23`C) from that point
+// till it intersects with RH = 0.8
+SH2 = 0.0184 // in kg H2O/kg air
+T2 = 27.3 // in degree C
+
+ma = (101.325-pw1)*1e3*V*M/(R*1e3*T1)
+
+mw = ma*(SH2-SH1)
+
+q_wat = mw*3600*10 // quantity of water required for 10 hours in kg
+
+
+// Output Results
+mprintf('The temperature of the air leaving the cooler = %4.1f degree C' , T2);
+mprintf('\n The specific humidity of air leaving cooler = %4.4f kg H2O/kg air' , SH2);
+mprintf('\n Quantity of water required to operate cooler for 10 hours = %4.1f kg',q_wat);
diff --git a/1919/CH9/EX9.13/Ex9_13.sce b/1919/CH9/EX9.13/Ex9_13.sce new file mode 100755 index 000000000..4f14f6c5b --- /dev/null +++ b/1919/CH9/EX9.13/Ex9_13.sce @@ -0,0 +1,51 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 13
+
+clear ;clc;
+
+//Given data
+mw3 = 1000 // cooling tower supply rate in kg/min
+T1 = 303.15 // Temp of air entering cooling tower in K
+RH1 = 0.3 // relative humidity of air entering cooler
+T2 = 308.15 // Temp of air leaving cooling tower in K
+RH2 = 0.8 // relative humidity of air leaving cooler
+T3 = 318.15 // Temp of water entering cooling tower in K
+T4 = 300.15 // Temp of water leaving cooling tower in K
+
+// subscript 1 and 2 denotes the state of air entering and leaving the cooling tower respectively
+// subscript 3 and 4 denotes the state of water entering and leaving the cooling tower respectively
+
+// data from psychometric chart for T = 30 degree C and RH = 0.3
+SH1 = 0.0078 // in kg H2O/kg air
+h1 = 51 // in kJ/kg air
+// data from psychometric chart for T = 35 degree C and RH = 0.8
+SH2 = 0.029 // in kg H2O/kg air
+h2 = 110 // in kJ/kg air
+hw3 = 188.45 // in kJ/kg
+hw4 = 113.25 // in kJ/kg
+
+// mass balance for H2O:
+//mw3-mw4 = ma*(SH2-SH1)
+
+// energy balance gives:
+// mw3*hw3 - mw4*hw4 = ma*(h2-h1)
+
+// x(1) = ma; x(2)= mw4;
+function[f] =F(x)
+ f(1) = mw3-x(2)-x(1)*(SH2-SH1);
+ f(2) = mw3*hw3 - x(2)*hw4 -x(1)*(h2-h1);
+endfunction
+x = [10 10];
+y = fsolve(x,F)
+
+ma = y(1); // air flow rate in kg/min
+mw4 = y(2);
+
+wat_mak = mw3-mw4; // make up water required
+
+// Output Results
+mprintf('Make up water required = %4.2f kg/min' , wat_mak);
+mprintf('\n Air flow rate = %4.1f kg/min' , ma);
diff --git a/1919/CH9/EX9.2/Ex9_2.sce b/1919/CH9/EX9.2/Ex9_2.sce new file mode 100755 index 000000000..ebcc7603b --- /dev/null +++ b/1919/CH9/EX9.2/Ex9_2.sce @@ -0,0 +1,35 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 2
+
+clear ;clc;
+
+//Given data
+X1 = 0.5 // volume fraction of propane
+X2 = 0.5 // volume fraction of oxygen
+P1 = 0.1 // initial pressure of mixture in MPa
+T1 = 300 // initial temperature of mixture in K
+P2 = 1.0 // final pressure of mixture in MPa
+N = 100 // number moles of gas mixture
+Cp1 = 74.0565 // molar heat capacity of propone in kJ/mol K
+Cv1 = 65.7442 // molar heat capacity of propone in kJ/mol K
+Cp2 = 29.4912 // molar heat capacity of oxygen in kJ/mol K
+Cv2 = 21.1776 // molar heat capacity of oxygen in kJ/mol K
+
+// Calculations
+Cp_m = X1*Cp1 + X2*Cp2 // molar heat capacity of gas mixture
+Cv_m = X1*Cv1 + X2*Cv2 // molar heat capacity of gas mixture
+
+gam = Cp_m/Cv_m // specific heat ratio
+
+T2 = T1*((P2/P1)^((gam-1)/gam)) // final temperature of mixture
+
+W = -N*Cv_m*(T2-T1) // Work required to compress gas mixture
+
+W = W*1e-3 // units conversion J to kJ
+
+// Output Results
+mprintf('Final temperature of gas mixture = %4.1f K' ,T2);
+mprintf('\n Work required to compress 100 mol of gas mixture = %4.2f kJ' ,W);
diff --git a/1919/CH9/EX9.3/Ex9_3.sce b/1919/CH9/EX9.3/Ex9_3.sce new file mode 100755 index 000000000..ee7d849ee --- /dev/null +++ b/1919/CH9/EX9.3/Ex9_3.sce @@ -0,0 +1,30 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 3
+
+clear ;clc;
+
+//Given data
+gam = 1.5 // specific heat ratio
+Cp1 = 20.7860 // molar heat capacity of Helium in kJ/mol K
+Cv1 = 12.4717 // molar heat capacity of Helium in kJ/mol K
+Cp2 = 28.6455 // molar heat capacity of Hydrogen in kJ/mol K
+Cv2 = 20.3311 // molar heat capacity of Hydrogen in kJ/mol K
+
+// Calculations
+// X1 be the molefraction of He in the mixture
+// CP_m = X1*Cp1 + (1-X1)*Cp2
+// Cv_m = X1*Cv1 + (1-X1)*Cv2
+// gam = (X1*Cp1 + (1-X1)*Cp2)/(X1*Cv1 + (1-X1)*Cv2)
+deff('y=mol_frac(X1)', 'y = gam-(X1*Cp1 + (1-X1)*Cp2)/(X1*Cv1 + (1-X1)*Cv2)')
+X1 = fsolve(0.1,mol_frac)
+
+
+X2 = (1-X1)*100 // volume composition of H2
+X1 = X1 * 100 // volume composition of He
+
+// Output Results
+mprintf('Volume percent composition of Helium = %4.2f ' ,X1);
+mprintf('\n Volume percent composition of Hydrogen = %4.2f ' ,X2);
diff --git a/1919/CH9/EX9.4/Ex9_4.sce b/1919/CH9/EX9.4/Ex9_4.sce new file mode 100755 index 000000000..906276247 --- /dev/null +++ b/1919/CH9/EX9.4/Ex9_4.sce @@ -0,0 +1,42 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 4
+
+clear ;clc;
+
+//Given data
+V = 5 // volume of tank in m^3
+X1 = 0.3 // volume fraction of Hydrogen
+X2 = 0.3 // volume fraction of Argon
+X3 = 0.4 // volume fraction of Methane
+Xf = 0.6 // final mixture composition of methane
+T = 300 // initial temperature of mixture in K
+P = 1 // initial pressure of mixture in MPa
+R = 8.314 // gas constant
+
+// Calculations
+p1 = X1*P // pressure of Hydrogen
+p2 = X2*P // pressure of Argon
+p3 = X3*P // pressure of Methane
+
+N1 = p1*1e3*V/(R*T) // pressure of Hydrogen
+N2 = p2*1e3*V/(R*T) // pressure of Argon
+N3 = p3*1e3*V/(R*T) // pressure of Methane
+
+
+
+// to determine the number of moles of methane in final mixture
+deff('y=moles(Nf)', 'y = Xf-(Nf/(N1+N2+Nf))')
+Nf = fsolve(0.1,moles)
+
+CH4_add = Nf-N3 // CH4 moles to be added
+
+N = N1 + N2 + Nf // total number of moles
+
+Pf = N*R*T/V * 1e-3 // Final pressure in MPa
+
+// Output Results
+mprintf('Amount of methane to be added = %4.4f kmol' , CH4_add);
+mprintf('\n Final pressure of mixture in Tank = %4.1f MPa' , Pf);
diff --git a/1919/CH9/EX9.5/Ex9_5.sce b/1919/CH9/EX9.5/Ex9_5.sce new file mode 100755 index 000000000..82aa4fbd8 --- /dev/null +++ b/1919/CH9/EX9.5/Ex9_5.sce @@ -0,0 +1,48 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 5
+
+clear ;clc;
+
+//Given data
+V = 1 // volume of tank in m^3
+P1 = 0.1 // pressure of tank with He in MPa
+T1 = 300 // temperature of tank with He in K
+P2 = 0.4 // pressure of tank with CO2 in MPa
+T2 = 600 // temperature of tank with CO2 in K
+Pf = 0.4 // pressure of tank after Co2 enters in MPa
+Cv1 = 12.4717 // molar heat capacity of He in kJ/kmol K
+Cv2 = 28.8354 // molar heat capacity of CO2 in kJ/kmol K
+Cp2 = 37.1444 // molar heat capacity of CO2 in kJ/kmol K
+R = 8.314 // gas constant
+
+// Calculations
+// N2*h = Uf-U0 (A)// First law of thermodynamics of transient flow
+// U0 = N1*Cv1*T1
+U0 = P1*1e3*V*Cv1/(R) // in kJ
+
+// Uf = (N1*Cv1 + N2*Cv2) * Tf
+//Tf = Pf*V/((N1+N2)*R)
+N1 = P1*1e3*V/(R*T1)
+
+// Uf = (N1*Cv1 + N2*Cv2) * Pf*V/((N1+N2)*R)
+
+// N2*h = (N1*Cv1 + N2*Cv2) * Pf*V/((N1+N2)*R) - U0
+
+// to determine the number of moles of CO2
+deff('y=moles(N2)', 'y = N2*Cp2*T2 - ((N1*Cv1 + N2*Cv2) * Pf*1e3*V/((N1+N2)*R)) + U0')
+N2 = fsolve(0.1,moles)
+
+Tf = Pf*1e3*V/((N1+N2)*R) // Final temperature of mixture in tank
+
+X2 = N2/(N1+N2) // molefraction of CO2
+X1 = 1 - X2 // molefraction of He
+
+// Output Results
+mprintf('Final temperature of mixture in tank = %4.2f K' , Tf);
+mprintf('\n The amount of CO2 enters the tank = %4.4f kmol' , N2);
+mprintf('\n Composition of CO2 in mixture = %4.4f ' , X2);
+mprintf('\n Composition of He in mixture = %4.4f ' , X1);
+
diff --git a/1919/CH9/EX9.6/Ex9_6.sce b/1919/CH9/EX9.6/Ex9_6.sce new file mode 100755 index 000000000..252a04e9c --- /dev/null +++ b/1919/CH9/EX9.6/Ex9_6.sce @@ -0,0 +1,34 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 6
+
+clear ;clc;
+
+//Given data
+V = 20*40*6 // dimensions of auditorium in cubic meters
+RH = 0.6 // relative humidy
+P = 101.325 // pressure of auditorium in kPa
+T = 303.15 // Temperature auditorium in K
+Ps_20 = 2.339 // saturation pressure of water at 20 degree C
+Ps_25 = 3.169 // saturation pressure of water at 25 degree C
+Ps_30 = 4.246 // saturation pressure of water at 30 degree C
+M = 18 // molecular weight of water
+R = 8.314 // gas constant
+
+// Calculations
+pw = RH*Ps_30 // partial pressure of water at 30 degree C
+
+SH = 0.622*pw/(P-pw) // specific humidity of air
+
+mw = pw*V*M/(R*T) // mass of water vapor in the auditorium
+
+ps = pw // at dew point from steam table T = 21.3 degree C
+
+// Output Results
+mprintf('(a) Partial pressure of water at 30 degree C = %4.4f kPa' , pw);
+mprintf('\n (b) Specific humidity of air = %4.3f kg H20/kg air' , SH);
+mprintf('\n (c) Mass of water vapor in the auditorium = %4.2f kg' , mw);
+mprintf('\n (d) Dew point = %4.4f kPa' , ps);
+
diff --git a/1919/CH9/EX9.7/Ex9_7.sce b/1919/CH9/EX9.7/Ex9_7.sce new file mode 100755 index 000000000..50a2febf4 --- /dev/null +++ b/1919/CH9/EX9.7/Ex9_7.sce @@ -0,0 +1,43 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 7
+
+clear ;clc;
+
+//Given data
+T1 = 313.15 // Temp of air entering adiabatic saturator in K
+P1 = 101.325 // pressure air entering saturator in kPa
+T3 = 298.15 // Temp of air leaving adiabatic saturator in K
+P3 = 101.325 // pressure air entering saturator in kPa
+
+ps = 3.169 // from steam tables at T = 313.15K (in kPa)
+RH = 1 // RH of steam leaving adiabatic saturator is 1
+pw = ps // from steam tables at 25 degree C
+
+SH_3 = 0.622*pw/(P3-pw) // specific humidity of air
+
+hfg_3 = 2442.3 // in kJ/kg
+hg_1 = 2574.3 // in kJ/kg
+hf_2 = 104.89 // in kJ/kg
+Cp_air = 1.0045 // in kJ/kg K
+
+SH1 = (Cp_air*(T3-T1) + SH_3*hfg_3) / (hg_1-hf_2)
+
+//SH1 = 0.622*pw_2/(P1-pw_2)
+deff('y=dew(pw_2)', 'y = SH1 - 0.622*pw_2/(P1-pw_2)')
+pw_2 = fsolve(0.01,dew)
+
+ps_40 = 7.384 // from steam table at 40 degree C
+
+RH1 = pw_2/ps_40
+
+ps_2 = pw_2 // at dew point ps = pw
+// Hence TDP = 18.8 degree C (from steam table)
+
+// Output Results
+mprintf('Specific humidity of entering air at 40 degree C = %4.4f kg H20/kg air' , SH1);
+mprintf('\n Relative humidity of air at 40 degree C = %4.3f ' , RH1);
+mprintf('\n Dew point = %4.3f kPa' , ps_2);
+
diff --git a/1919/CH9/EX9.8/Ex9_8.sce b/1919/CH9/EX9.8/Ex9_8.sce new file mode 100755 index 000000000..85dd8fe60 --- /dev/null +++ b/1919/CH9/EX9.8/Ex9_8.sce @@ -0,0 +1,48 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 8
+
+clear ;clc;
+
+//Given data
+T1 = 313.15 // Temp of air entering adiabatic saturator in K
+P1 = 101.325 // pressure air entering saturator in kPa
+T3 = 298.15 // Temp of air leaving adiabatic saturator in K
+P3 = 101.325 // pressure air entering saturator in kPa
+
+ps = 3.169 // from steam tables at T = 313.15K (in kPa)
+RH = 1 // RH of steam leaving adiabatic saturator is 1
+pw = ps // from steam tables at 25 degree C
+
+SH_3 = 0.622*pw/(P3-pw) // specific humidity of air
+
+hfg_3 = 2442.3 // in kJ/kg
+hg_1 = 2574.3 // in kJ/kg
+hf_2 = 104.89 // in kJ/kg
+Cp_air = 1.0045 // in kJ/kg K
+
+SH1 = (Cp_air*(T3-T1) + SH_3*hfg_3) / (hg_1-hf_2)
+
+//SH1 = 0.622*pw_2/(P1-pw_2)
+deff('y=dew(pw_2)', 'y = SH1 - 0.622*pw_2/(P1-pw_2)')
+pw_2 = fsolve(0.01,dew)
+
+ps_40 = 7.384 // from steam table at 40 degree C
+
+RH1 = pw_2/ps_40
+
+ps_2 = pw_2 // at dew point ps = pw
+// Hence TDP = 18.8 degree C (from steam table)
+
+// enthalphy of mixture
+//h1 = h_a1 + SH1*h_w1
+h1 = Cp_air*(T1-273.15) + SH1*hg_1
+
+
+// Output Results
+mprintf('Specific humidity of entering air at 40 degre C = %4.3f kg H20/kg air' , SH1);
+mprintf('\n Relative humidity of air at 40 degree C = %3.2f ' , RH1);
+mprintf('\n Dew point = %2.1f kPa' , ps_2);
+mprintf('\n Enthalphy of mixture = %2.0f kJ/kg air' , h1);
diff --git a/1919/CH9/EX9.9/Ex9_9.sce b/1919/CH9/EX9.9/Ex9_9.sce new file mode 100755 index 000000000..0f089681a --- /dev/null +++ b/1919/CH9/EX9.9/Ex9_9.sce @@ -0,0 +1,38 @@ +
+// Theory and Problems of Thermodynamics
+// Chapter 9
+// Air_water Vapor Mixtures
+// Example 9
+
+clear ;clc;
+
+//Given data
+V1 = 2 // volume of air conditioner delivers in cubic meter
+T1 = 278.15 // Temp of air completely saturates in K
+V2 = 5 // volume of air mixed in cubic meter
+T2 = 308.15 // Temp of air mixed in K
+RH = 0.4 // relative humidity in room
+R = 8.314 // gas constant
+M = 28.97 // molecular weight of air
+
+// data from psychometric chart
+SH1 = 0.0056 // in kg H2O/kg air
+pw1 = 0.8 // in kPa
+// at TDB = 5 degree C; RH = 1
+SH2 = 0.0138 // in kg H2O/kg air
+pw2 = 2.2 // in kPa
+
+// at TDB = 5 `C; RH = 1
+ma1 = (101.325-pw1)*1e3*V1*M/(R*1e3*T1)
+ma2 = (101.325-pw2)*1e3*V2*M/(R*1e3*T2)
+
+//ma1/ma2 = (SH2-SH3)/(SH3-SH1)
+deff('y=SH(SH3)', 'y = ma1/ma2 - (SH2-SH3)/(SH3-SH1)')
+SH3 = fsolve(0.01,SH)
+
+// Join the states 1 and 2 by a straight line and read TDB = 26 degree C and
+// RH3=0.55 at the intersection of the line with SH3=0.0113 kg H20/kg air
+
+
+// Output Results
+mprintf('Specific humidity of air after mixing = %4.4f kg H20/kg air' , SH3);
|