clc // Part (a) h1 = 2758 // Enthalpy at state 1 in kJ/kg h2 = 1817 // Enthalpy at state 2 in kJ/kg h3 = 192 // Enthalpy at state 3 in kJ/kg h4 = 200// Enthalpy at state 4 in kJ/kg Wt = h1-h2 // turbine work Wp = h4-h3 // Pump work Q1 = h1-h4 // Heat addition Wnet = Wt-Wp // Net work doen n1 = Wnet/Q1 // First law efficiency WR = Wnet/Wt // Work ratio Q1_ = 100 // Heat addition rate in MW PO = n1*Q1_ // power output cpg = 1000 // Specific heat capacity in J/kg wg = (Q1_/(833-450)) // mass flow rate of gas EIR = wg*cpg*((833-300)-300*(log(833/300)))/1000 // Exergy input n2 = PO/EIR // Second law efficiency printf("\n Example 12.8\n") printf("\n Part (a)") printf("\n The first law efficiency n1 is %f",n1*100) printf("\n The second law efficiency n2 is %f",n2*100) printf("\n The work ratio is %f",WR) // Part (b) h1b = 3398 // Enthalpy at state 1 in kJ/kg h2b = 2130 // Enthalpy at state 2 in kJ/kg h3b = 192 // Enthalpy at state 3 in kJ/kg h4b = 200// Enthalpy at state 4 in kJ/kg Wtb = 1268 // turbine work in kJ/kg Wpb = 8 // Pump work in kJ/kg Q1b = 3198// Heat addition rate in kW n1b = (Wtb-Wpb)/Q1b //first law efficiency WRb = (Wtb-Wpb)/Wtb // WOrk ratio EIRb = 59.3 // Exergy input rate in MW Wnetb = Q1_*n1b // net work done n2b = Wnetb/EIRb // Second law efficiency printf("\n Part (b)") printf("\n The first law efficiency n1 is %f",n1b*100) printf("\n The second law efficiency n2 is %f",n2b*100) printf("\n The work ration is %f",WRb) // Part (c) h1c = 3398 // Enthalpy at state 1 in kJ/kg h2c = 2761 // Enthalpy at state 2 in kJ/kg h3c = 3482 // Enthalpy at state 3 in kJ/kg h4c = 2522 // Enthalpy at state 4 in kJ/kg h5c = 192 // Enthalpy at state 5 in kJ/kg h6c = 200// Enthalpy at state 6 in kJ/kg Wt1 = 637 // Turbine work in kJ/kg Wt2 = 960 // Turbine work in kJ/kg Wtc = Wt1+Wt2 // Net turbine work in kJ/kg Wp = 8 // Pump work in kJ/kg Wnetc = Wtc-Wp // net work done Q1c = 3198+721 // Heat addition n1c = Wnetc/Q1c// First law efficiency WRc = Wnetc/Wtc// Work ratio POc = Q1_*n1c// Power output EIRc = 59.3// Exergy input in MW n2c = POc/EIRc // Second law efficiency printf("\n Part (c)") printf("\n The first law efficiency n1 is %f",n1c*100) printf("\n The second law efficiency n2 is %f",n2c*100) printf("\n The work ration is %f",WRc) // Part (d) T3 = 45.8 // saturation temperature at 0.1 bar in degree celsius T1 = 295 // saturation temperature at 80 bar in degree celsius n1d = 1-((T3+273)/(T1+273)) // First law efficiency Q1d = 2758-1316 // Heat addition Wnet = Q1d*n1d // Net work output Wpd = 8 // Pump work in kJ/kg Wtd = 641// Turbine work in kJ/kg WRd = (Wt-Wp)/Wt // Work ratio POd = Q1_*0.439// Power output EIRd = (Q1_/(833-593))*cpg*((833-300)-300*(log(833/300)))/1000 //Exergy Input rate in MW n2d = POd/EIRd // Second law efficiency printf("\n Part (d)") printf("\n The first law efficiency n1 is %f",n1d*100) printf("\n The second law efficiency n2 is %f",n2d*100) printf("\n The work ration is %f",WRd) //The answers vary due to round off error