A simple power plant utilizing the Rankine Cycle operates with an inlet boiler pressure of 5 MPa and an inlet condenser pressure of 300 kPa. Because of frictional effects, the pressure of the water drops 0.3 MPa in the boiler and 3 kPa in the condenser. The temperature of the steam as it enters the turbine is 700 °C. The adiabatic efficiency of the pump and of the turbine are 83 percent and 88 percent, respectively. The pump and the turbine are adiabatic, and the water enters the pump as saturated liquid. It can be assumed that heat transfer to the water in the boiler is from a reservoir at 1500 K, and the environment is at 25 °C. Determine the thermal efficiency of the cycle and compare it with the thermal efficiency of (a) a Carnot cycle, and (b) the ideal Rankine Cycle. Specify the amount of entropy generated in each step of the real cycle
A simple power plant utilizing the Rankine Cycle operates with an inlet boiler pressure
of 5 MPa and an inlet condenser pressure of 300 kPa. Because of frictional effects, the
pressure of the water drops 0.3 MPa in the boiler and 3 kPa in the condenser. The
temperature of the steam as it enters the turbine is 700 °C. The adiabatic efficiency of
the pump and of the turbine are 83 percent and 88 percent, respectively. The pump
and the turbine are adiabatic, and the water enters the pump as saturated liquid. It can
be assumed that heat transfer to the water in the boiler is from a reservoir at 1500 K,
and the environment is at 25 °C.
Determine the thermal efficiency of the cycle and compare it with the thermal efficiency
of (a) a Carnot cycle, and (b) the ideal Rankine Cycle. Specify the amount of entropy
generated in each step of the real cycle
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