Question

A simple Rankine cycle uses water as the working fluid. The boiler operates at 6000 kPa and the condenser at 40 kPa. At the entrance to the turbine, the temperature is 380 °C. The isentropic efficiency of the turbine is 88 %, pressure and pump losses are negligible, and the water leaving the condenser is subcooled by 5.9 °C. The boiler is sized for a mass flow rate of 17 kg/s. Determine the following values. °C m®/kg 1 kJ/kg (1) The temperature at the pump inlet. 69.96 (2) The specific volume at the pump inlet. 0.001026 (3) The specific enthalpy at the turbine exit. | (4) The rate at which heat is added in the boiler. (5) The power required to operate the pumps. X 18084.4 (6) The net power produced by the cycle. 13404.9 (7) The thermal efficiency. 0 kW kW kW

Answer 1

1-2 asentropic 03 compression 103 a Turbine t Turbine 2-3 - Heat addition at Condenser I Boiler / Constant pressure 3-4 4-1 - 9 sentropic expansion Heat rejection a constant pressure P2 = P = 6000 kPa = 6 MPa Pq =P = 40kPa = 0.04 MPa Tg = 3800 m = 881=0.88 Ti = 5.9°C moln : 11 kg/see I Aboiley Hz-HA IMT = Tg-ha' Tempreture Presente H₂ = 3200 kJ/kg [corresponding & to 6 MPa 838000 Entropy S3 = 6.2=5 Ho: 2200 kJ/kg 1 x = 80." (quality of rapour) 3200 - MG 3200-44 = 880 m. - Harha - 0.88 = - 3200 - 200 ₂-hal - ha= 2320 a specific enthalpy at Turbine enit.

hi = 300 kJ/kg [coresponding to saturated liquid at 40 kPa Si=S2 = 1 kiligh 27 325 kJ/kg [ corresponding to S2 = 1 kil dag & P = 6 MPa Work required for pump = Power m (harti) 11 (321-300) = 425 KW B. Net Power produced by cycle - – Power required Power produced by turbine by pump in (hy ha) - in Chechi) 0 17 3200–2320] -428 - 1453 5 kW Ned. Power produced by Cycle = 14535 kW B. Rate at which heat is added in boiler Q boiler : in (ho-hip) : 17(3200-325) = 40 250 kw 14383 3x100 Net work done Net Heat added do2ro Thermal efficiency - = 35.60MM
I had taken all values from Pressure enthalpy chart so it may be chance in deviation in answer.