A power plant operates using Rankine cycle with an open feed water heater and a closed feedwater heater, with water being the working fluid. The vapor enters the turbine at 16 MPa,560°C. The lowest pressure in the cycle is the condenser pressure at 8 kPa. The mass flow rate of steam entering the turbine is 120 kg/s. The extracted steam for the closed feedwater heater is at 4 MPa, and that for open feed water heater is at 0.3 MPa. Saturated liquid condensate leaves the closed feedwater heater at 4 MPa and is collected in the open feed waterheater. The feed water leaves the closed heater at 16 MPa and a temperature equal to the saturation temperature at 4 MPa. Saturated liquid leaves the open heater at 0.3 MPa. Assume that the isentropic efficiencies of the turbine stages and pumps are 85%. a) Illustrate the above power plant, with all given data, on a schematic diagram. b) Explain the working principles of closed and open feedwater heaters, together with the advantages and disadvantages of each. c) Draw the cycleon a T-s diagram. d) The net power developed, in kW e) The rate of heat transfer to the steam in the steam generator, in kW f) The thermal efficiency. g) The mass flow rate of cooling water in the condenser, given that its temperature rise shouldn't exceed 18°C. Neglect pressure drop in the condenser.

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