EE 703 · Chapter 7
A steam power plant on Rankine cycle has steam entering HP turbine at 20 MPa, 500°C and leaving LP turbine at 89.6% dryness. Condenser pressure=0.005 MPa, reheating upto 500°C. Determine: a) Pressure at which steam leaves HP turbine b) Thermal efficiency.
On a reheat cycle, steam leaves the boiler and enters the turbine at 4 MPa, 400°C. After expansion in the turbine to 400 kPa, the steam is reheated to 400°C and then expanded in the low-pressure turbine to 10 kPa. Determine the cycle efficiency.
On a regenerative cycle, steam leaves the boiler and enters the turbine at 4 MPa, 400°C. After expansion to 400 kPa, some of the steam is extracted from the turbine to heat the feedwater in an open feedwater heater. The pressure in the feedwater heater is 400 kPa, and the water leaving it is saturated liquid at 400 kPa. The steam not extracted expands to 100 kPa. Determine the cycle efficiency.