Water is the working fluid in a regenerative Rankine cycle power plant with one open feedwater...

 

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Water is the working fluid in a regenerative Rankine cycle power plant with one open feedwater heater and reheat. Vapor enters the first-stage turbine at 120 bar, 550°C with a mass flow rate of 120 kg/s. The condenser pressure is 0.08 bar. Steam expands through the first-stage turbine to 10 bar, where some of the steam is extracted and diverted to the open feedwater heater operating at 10 bar. The remainder is reheated to 500°C and then expands through the second-stage turbine to the condenser pressure. Saturated liquid exits the feedwater heater at the feedwater heater pressure. Cooling water enters the condenser at 25°C and exits at 35°C with no significant change in pressure. Let To = 25°C. po = 1 bar. (a) For the ideal cycle, detemine the net power in kW and the thermal efficiency. (b) Repeat for turbine stage and pump isentropic efficiencies of 85%. (c) Determine the rate of exergy transfer, in kW, to the working fluid passing through the steam generator and perform calculations to account for all outputs, losses, and destructions of exergy for the cases of (a) and (b). Compare. Perform the calculations using steam table data and using IT and validate the IT results. Turbine 1 Steam Generator 1-y Reheat Condenser Open Feedwater Cooling Water Heater Pump 1 Pump 1 Water is the working fluid in a regenerative Rankine cycle power plant with one open feedwater heater and reheat. Vapor enters the first-stage turbine at 120 bar, 550°C with a mass flow rate of 120 kg/s. The condenser pressure is 0.08 bar. Steam expands through the first-stage turbine to 10 bar, where some of the steam is extracted and diverted to the open feedwater heater operating at 10 bar. The remainder is reheated to 500°C and then expands through the second-stage turbine to the condenser pressure. Saturated liquid exits the feedwater heater at the feedwater heater pressure. Cooling water enters the condenser at 25°C and exits at 35°C with no significant change in pressure. Let To = 25°C. po = 1 bar. (a) For the ideal cycle, detemine the net power in kW and the thermal efficiency. (b) Repeat for turbine stage and pump isentropic efficiencies of 85%. (c) Determine the rate of exergy transfer, in kW, to the working fluid passing through the steam generator and perform calculations to account for all outputs, losses, and destructions of exergy for the cases of (a) and (b). Compare. Perform the calculations using steam table data and using IT and validate the IT results. Turbine 1 Steam Generator 1-y Reheat Condenser Open Feedwater Cooling Water Heater Pump 1 Pump 1

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KNOWN The ideal Rankine aycle of Probem 89 is modified to inelude one clesed aud oneopen feedwater h... View the full answer