Problem 8.045 SI
Consider a regenerative vapor power cycle with two feedwaterheaters, a closed one and an open one, and reheat. Steam enters thefirst turbine stage at 12 MPa, 560°C, and expands to 2 MPa. Somesteam is extracted at 2 MPa and fed to the closed feedwater heater.The remainder is reheated at 2 MPa to 520°C and then expandsthrough the second-stage turbine to 0.3 MPa, where an additionalamount is extracted and fed into the open feedwater heateroperating at 0.3 MPa.
The steam expanding through the third-stage turbine exits at thecondenser pressure of 60 kPa. Feedwater leaves the closed heater at210°C, 12 MPa, and condensate exiting as saturated liquid at 2 MPais trapped into the open feedwater heater. Saturated liquid at 0.3MPa leaves the open feedwater heater. Assume all pumps and turbinestages operate isentropically.
Determine for the cycle:
(a) the heat transfer to the working fluid passing through thesteam generator, in kJ per kg of steam entering the firststageturbine.
(b) the percent thermal efficiency.
(c) the heat transfer from the working fluid passing through thecondenser to the cooling water, in kJ per kg of steam entering thefirst-stage turbine.
