Compare your results for the Rankine cycle with an open feedwater heater in Problem 9.45 with your results for the simple Rankine cycle with superheat. Both problems consider Rankine cycles operating across the same high and low pressures and the same maximum temperature

A. Determine the fraction of the total flow extracted from the turbine and the mass flow rate of the extracted steam.

B. Determine the power (kW) required to pump the condensate into the feedwater heater.

C. Determine the rate of heat addition (kW) in the steam generator section (state 2 to state 3).

D. Determine the power produced by the high-pressure portion of the turbine. Also determine the power delivered by the low-pressure turbine stages, after the extraction steam is removed.

E. Find the total power produced by the two turbine stages.

Problem 9.45

Consider an ideal regenerative Rankine cycle utilizing an open feedwater heater, as shown in Fig. 9.17. The turbine inlet conditions are 10 MPa and 700 K, and the condenser pressure is 10 kPa. The mass flow rate of the steam entering the turbine is 12 kg/s. Steam is extracted between turbine stages at 2.2MPa

Fig. 9.17

Transcribed Image Text:

Temperature (K) 800 600 400 F 0 2.0 4.0 10 MPa 6.0 Entropy (kJ/kg.K) 2.2 MPa 10 kPa 8.0 10.0