4-Assume a regenerative feedwater heating steam cycle with two closed feedwater heaters and one open feedwater...

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4-Assume a regenerative feedwater heating steam cycle with two closed feedwater heaters and one open feedwater heater/deaerator. Steam enters the turbine at 125 bars, 500C. Overall efficiency of the steam turbine is 0.9. Condenser pressure is 0.1 bar. The drain from the last closed FWH returns to the condenser. Furthermore, we have the following data known; Feed water temperature before entering the boiler is 250C. Temperature at the outlet of the open feedwater heater is 100C and the pressure is 1.2 times the admission pressure. Where the admission pressure is 125 bars as mentioned earlier. The work from the condenser pump can be ignored. The thermal temperature difference (TTD) is taken 4C for both closed FWHs. There is no drain cooling (drain water leaves the closed heaters in saturated condition. Find the percentage mass flow rates which go into each heater. Whenever needed, an equal amount of feed water heating can be assumed along the heaters to calculate the unknown temperatures, according to formula below where n is the number of heaters T = K where K= . n n-1 TFW T cond. (1)- (13) (2) Turbine (6) (5)- (4)- FWT/DEAE (11) (12) (7)+ (8) (9) (10) + 4-Assume a regenerative feedwater heating steam cycle with two closed feedwater heaters and one open feedwater heater/deaerator. Steam enters the turbine at 125 bars, 500C. Overall efficiency of the steam turbine is 0.9. Condenser pressure is 0.1 bar. The drain from the last closed FWH returns to the condenser. Furthermore, we have the following data known; Feed water temperature before entering the boiler is 250C. Temperature at the outlet of the open feedwater heater is 100C and the pressure is 1.2 times the admission pressure. Where the admission pressure is 125 bars as mentioned earlier. The work from the condenser pump can be ignored. The thermal temperature difference (TTD) is taken 4C for both closed FWHs. There is no drain cooling (drain water leaves the closed heaters in saturated condition. Find the percentage mass flow rates which go into each heater. Whenever needed, an equal amount of feed water heating can be assumed along the heaters to calculate the unknown temperatures, according to formula below where n is the number of heaters T = K where K= . n n-1 TFW T cond. (1)- (13) (2) Turbine (6) (5)- (4)- FWT/DEAE (11) (12) (7)+ (8) (9) (10) +