Water is the working fluid in a regenerative Rankine cycle. Steam exits the first-stage turbine at 8 bar and its quality is 95%. 20% of that steam is extracted and diverted to an open feed water heater operating at 8 bar. The remaining steam expands through the second stage turbine to the condenser pressure of 6 kPa. Saturated liquid exits the condenser and is pumped to the open feed water heater by the low-pressure pump. Saturated liquid exits the open feed water heater at 8 bars.
Determine:
1. The work input necessary to operate the low pressure pump, in kJ per kg of water flowing through the pump.
2. The istentropic efficiency of the low pressure pump.