A regenerative steam cycle uses two closedfeed heaters. Determine the amount of steam bled at each stage, the work output of the plant and cycle efficiency. It is known that: pA=40 bar, tA=500 C, pB=10 bar, pC=1.0 bar, pD=0.035 bar. Isentropic efficiencies of the steam turbine and pump are 0.85 and 0.90 respectively. Boiler supplies 10 kg/s steam to the turbine.
Inputs 
Units 

Pressure at A 
40,00 
bar 
temperature at A 
500,00 
C 
Pressure at B 
10,00 
bar 
Pressure at C 
1,00 
bar 
Pressure at D 
0,035 
bar 
Pressure at G 
40,00 
bar 
Mass flow through the system 
10,00 
kg/s 
Turbine isentropic eff. 
0,85 
. 
Pump isentropic eff. 
0,90 
. 
Outputs 

Spec. enthalpy at A 
3444,99 
kJ/kg 
Spec. entropy at A 
7,09 
kJ/(kg.K) 
Isentropic enthalpy at B 
3032,71 
kJ/kg 
Spec. enthalpy at B 
3094,55 
kJ/kg 
Power generated at stage 1, POW1 
3504,33 
kW 
. 
. 
. 
Spec. entropy at B 
7,20 
kJ/(kg.K) 
Isentropic enthalpy at C 
2615,07 
kJ/kg 
Spec. enthalpy at C 
2686,99 
kJ/kg 
Power generated at stage 2, POW2 
3472,49 
kW 
. 
. 
. 
Spec. entropy at C 
7,39 
kJ/(kg.K) 
Isentropic enthalpy at D 
2210,69 
kJ/kg 
Spec. enthalpy at D 
2282,14 
kJ/kg 
Power generated at stage 3, POW3 
3003,49 
kW 
. 
. 
. 
Spec. enthalpy at H 
111,85 
kJ/kg 
Spec. entropy at H 
0,39 
kJ/(kg.K) 
Isentropic enthalpy at G 
116,00 
kJ/kg 
Spec. enthalpy at G 
116,47 
kJ/kg 
Power req. for pump 
46,21 
kW 
. 
. 
. 
For the throttling process, IJ 
. 
. 
hE = hI = hJ 
762,61 
kJ/kg 
For the throttling process, KL 
. 
. 
hF = hK = hL 
417,51 
kJ/kg 
Energy balance on FH1 gives, mB 
1,48 
kg/s 
Energy balance on FH2 gives, mC 
1,10 
kg/s 
Net power generated 
9934,10 
kW 
Cycle efficiency 
0,370 
. 