Regenerative Rankine Cycle, Open Feedwater Heater
Water is the working fluid in an ideal regenerative Rankine Cycle, as shown. Superheated vapor enters the turbine at 10 MPa and 480°C, and the condenser pressure is 6kPa. Steam expands through the first stage turbine to 0.7MPa where some of the steam is extracted and diverted to an open feedwater heater operating at 0.7MPa. The remaining steam expand through the second stage turbine to the condenser pressure of 6kPa. Saturated liquid exits the feedwater heater at 0.7MPa. Assume pump and each turbine stage have an isentropic efficiency of 80%.
A. Calculate the heat addition in kJ/kg of steam entering the first stage turbine.
B. The thermal efficiency
C. The rate of heat transfer from the working fluid passing through the condenser to thecooling water in kJ/kg of steam entering the first-stage turbine.