5. (15 marks total) HP turbine QN boiler 5 M3 6 MR LP turbine W 7...

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5. (15 marks total) HP turbine QN boiler 5 M3 6 MR LP turbine W 7 3 WPHP high pressure pump feedwater heater -WPLP low pressure pump QOUT condenser The sketch shows a steam power cycle with one open feedwater heater. The follow cycle states are given: 1: saturated liquid at 50C 2: P = 0.3 MPa 3: saturated liquid 4: P = 5.0 MPa 5: T, = 400C The isentropic efficiency of both pumps is n. -80%, and the isentropic efficiency of both turbines is n = 90%. (a) (2 marks) Sketch a T-s diagram of the cycle. (b) (4 marks) Determine the low pressure pump specific work Wp in kJ/kg and the enthalpy h, at the low pressure pump exit. HP (c) (4 marks) Determine the high pressure turbine specific work WT Hp in kJ/kg and the enthalpy h at the high pressure turbine exit. (d) (5 marks) Calculate the ratio of the mass flow passing through the low pressure pump. extracted from the turbine to the mass flow m 5. (15 marks total) HP turbine QN boiler 5 M3 6 MR LP turbine W 7 3 WPHP high pressure pump feedwater heater -WPLP low pressure pump QOUT condenser The sketch shows a steam power cycle with one open feedwater heater. The follow cycle states are given: 1: saturated liquid at 50C 2: P = 0.3 MPa 3: saturated liquid 4: P = 5.0 MPa 5: T, = 400C The isentropic efficiency of both pumps is n. -80%, and the isentropic efficiency of both turbines is n = 90%. (a) (2 marks) Sketch a T-s diagram of the cycle. (b) (4 marks) Determine the low pressure pump specific work Wp in kJ/kg and the enthalpy h, at the low pressure pump exit. HP (c) (4 marks) Determine the high pressure turbine specific work WT Hp in kJ/kg and the enthalpy h at the high pressure turbine exit. (d) (5 marks) Calculate the ratio of the mass flow passing through the low pressure pump. extracted from the turbine to the mass flow m