Consider a cogeneration system operating as shown in the figure below. Steam enters the first turbine...

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Consider a cogeneration system operating as shown in the figure below. Steam enters the first turbine stage at 6 MPa, 540C. Between the first and second stages, y = 45% of the steam is extracted at 500 kPa and diverted to a process heating load of 2process = 5x108 kJ/h. Condensate exits the process heat exchanger at 450 kPa with specific enthalpy of 589.13 kJ/kg and is mixed with liquid exiting the lower-pressure pump at 450 kPa. The entire flow is then pumped to the steam generator pressure. At the inlet to the steam generator the specific enthalpy is 469.91 kJ/kg. Saturated liquid at 60 kPa leaves the condenser. The turbine stages and the pumps operate with isentropic efficiencies of 82% and 88%, respectively. Qin (1-y) Steam generator P1-6 MPa T = 540C Turbine =82% (1) P=P = 6 MPa h = 469.91 kJ/kg Pump 2 77p2 = 88% W 12 P6 Ps 450 kPa Pump 1 P=500 kPa (1-y) 7pl = 88% Heat exchanger P = 450 kPa 8 hg=589.13 kJ/kg Determine: (a) the mass flow rate of steam entering the first turbine stage, in kg/s. (b) the net power developed by the cycle, in MW. (c) the rate of entropy production in the turbine, in kW/K. 3 P3 = 60 kPa Qout Condenser P4=P3 = 60 kPa x=0 (saturated liquid) Qprocess Consider a cogeneration system operating as shown in the figure below. Steam enters the first turbine stage at 6 MPa, 540C. Between the first and second stages, y = 45% of the steam is extracted at 500 kPa and diverted to a process heating load of 2process = 5x108 kJ/h. Condensate exits the process heat exchanger at 450 kPa with specific enthalpy of 589.13 kJ/kg and is mixed with liquid exiting the lower-pressure pump at 450 kPa. The entire flow is then pumped to the steam generator pressure. At the inlet to the steam generator the specific enthalpy is 469.91 kJ/kg. Saturated liquid at 60 kPa leaves the condenser. The turbine stages and the pumps operate with isentropic efficiencies of 82% and 88%, respectively. Qin (1-y) Steam generator P1-6 MPa T = 540C Turbine =82% (1) P=P = 6 MPa h = 469.91 kJ/kg Pump 2 77p2 = 88% W 12 P6 Ps 450 kPa Pump 1 P=500 kPa (1-y) 7pl = 88% Heat exchanger P = 450 kPa 8 hg=589.13 kJ/kg Determine: (a) the mass flow rate of steam entering the first turbine stage, in kg/s. (b) the net power developed by the cycle, in MW. (c) the rate of entropy production in the turbine, in kW/K. 3 P3 = 60 kPa Qout Condenser P4=P3 = 60 kPa x=0 (saturated liquid) Qprocess