Calculate the thermal efficiency of a simple Rankine cycle for which steam leaves the boiler as a saturated vapor at 3x106 N/m2 and is condensed to saturated liquid at 7,000 N/m2. The pump and turbine have isentropic efficiencies of 0.6 and 0.8, respectively. The pump inlet is saturated liquid.

Consider a steam power plant operating on the ideal Rankine cycle. Steam enters the turbine at 3 MPa and 350°C and is condensed in the condenser at a pressure of 10 kPa. Determine

A flashed steam geothermal power plant is located where underground hot water is available as a saturated liquid at 700 kPa. The well-head pressure is 600 kPa. The flashed steam enters the steam turbine at 500 kPa and expands to 15 kPa when it is condensed. The flow rate from the well is 29.6 kg/s. Determine the cycle thermal efficiency of the plant in %. If the steam table is needed, please use the green book entitled "Thermodynamics Properties of Water Including Vapor, Liquid, and Solid Phases" by Keenan, Keyes, Hill, and Moore.

In the ideal Rankine cycle shown, the boiler pressure is 6 MPa and the condenser pressure is 8 kPa. The steam enters the turbine at 440°C at a mass flow rate of 7.0 kg/s. In your written solution, (a) determine the enthalpies at states 1, 2, 3, and 4; (b) draw the T-s diagram with the states in the correct region; (c) determine the cycle power output; and (d) the cycle thermal efficiency.

A simple ideal Rankine cycle with water as the working fluid operates between the pressure limits of 3 MPa in the boiler and 30 kPa in the condenser. If the quality at the exit of the turbine cannot be less than 80 percent, what is the maximum thermal efficiency this cycle can have? Use steam tables. The maximum thermal efficiency is %.

A simple Rankine cycle uses water as the working fluid. The boiler operates at 6400 kPa and the condenser at 70 kPa. At the entrance to the turbine, the temperature is 490 °C. The isentropic efficiency of the turbine is 84 %, pressure and pump losses are negligible, and the water leaving the condenser is subcooled by 6.7 °C. The boiler is sized for a mass flow rate of 18 kg/s. Determine the following values. (1) The temperature at the pump inlet. / 80.3 (2) The specific volume at the pump inlet. (3) The specific enthalpy at the turbine exit. X 346 (4) The rate at which heat is added in the boiler. (5) The power required to operate the pumps. (6) The net power produced by the cycle. (7) The thermal efficiency. o °C O m/kg O kJ/kg O kW O kW O kW 0.001030

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A 283-MW steam power plant operates on the Rankine cycle but with turbine and pump efficiencies of 90%. The steam enters the turbine at 10,000 kPa and 550°C. It discharges to the condenser at 50 kPa. Determine the thermal efficiency in percent.