Water is the working fluid in a regenerative Rankine cycle with one open feedwater heater and one closed feedwater heater. Steam enters the first turbine at 12 MPa and 560 o
C and expands to 1 MPa, where
some of the steam is extracted and diverted to the closed feedwater heater. The remaining steam expands
through the second-stage turbine to 0.2 MPa and some steam is extracted and diverted to the open
feedwater heater. The remaining steam expands through the third-stage turbine exits at a pressure of 6
kPa. Feedwater leaves the closed heater at 200o
C and condensate exits as a saturated liquid is trapped
into the open feedwater heater. Saturated liquid leaves the open feedwater heater. Assume no pressure
drops in steam generator, lines, condenser or feedwater heaters. All pumps and turbines operate
isentropically. For the cycle:
a) draw an illustration of this setup, clearly labelling each state and fraction of fluid flowing.
b) draw these states and processes on a T-s diagram.
c) the pressure, temperature and enthalpy for each state, summarizing these values in a data table.
d) the energy rate balance equations for each device in the setup.
e) the rate of heat transfer to the working fluid passing through the steam generator, in kJ per kg of steam
entering the first-stage turbine.
f) the thermal efficiency of the cycle