1. Steam is supplied to a steam turbine at 35 bar and 380 °C. The exhaust pressure is 0.035 bar, ... more 1. Steam is supplied to a steam turbine at 35 bar and 380 °C. The exhaust pressure is 0.035 bar, and x = 0.89. The steam consumption is 6 tons per hour. Calculate the following: a. Thermal efficiency of the cycle. b. Power of the turbine. c. Heat removed from steam in the condenser. d. Power of the feed pump, if the water is compressed isentropically. 2. Steam at 20 bar and 300 °C enters a steam turbine-generator unit. The exhaust pressure is 0.06 bar. The steam consumption in the turbine is 6.5-kg/ kWh of the generator output. The combined mechanical and generator efficiency is 84%. What is the condition of steam at the condenser inlet? 3. Steam leaves the boiler of a power plant at 34 bars and 375 °C, and when it enters the turbine it is at 32.5 bars and 350 °C. The turbine efficiency is 85% and the exhaust pressure is 0.12 bar. Condensate leaves the condenser and enters the pump at 0.12 bar and 38 °C. The pump efficiency is 75% and the discharge pressure is 37.5 bars. The feedwater enters the boiler at 36 bars and 36 °C. Calculate: a. The thermal efficiency of the cycle. b. The irreversibility of the process between the boiler exit, and the turbine inlet, assuming an ambient temperature of 25 °C. 4. A steam turbine receives steam at 40 bars and 420 °C. The steam expands with an isentropic efficiency of 75%. When the steam becomes dry saturated it is taken to a reheat section of the boiler, where the temperature is raised to 200 °C. The steam, then, expands to the condenser pressure with an isentropic efficiency of 75% also. Find the reheat pressure, and the amount of reheat given to each kilogram of steam. If the condenser vacuum is 69 cm Hg, calculate the efficiency of the cycle and the power of the turbine for a steam consumption of 20 tons per hour. Calculate also the fuel consumption in the boiler if the C.V. of the fuel is 42,700 kJ/kg, and the boiler efficiency is 88 %. 5. In an 80 MW nuclear power plant, heat is transferred in the reactor to liquid sodium. The liquid sodium is then pumped to a heat exchanger, where heat is transferred to steam. The steam leaves this heat exchanger as saturated vapor at 55 bars, and is then superheated in an external gas-fired superheater to 550 °C. The steam then enters the turbine, which has one extraction point at 4 bars, where steam flows to an open-type feedwater heater. The turbine isentropic efficiency is 80 %, and the condenser pressure
1. Steam is supplied to a steam turbine at 35 bar and 380 °C. The exhaust pressure is 0.035 bar, ... more 1. Steam is supplied to a steam turbine at 35 bar and 380 °C. The exhaust pressure is 0.035 bar, and x = 0.89. The steam consumption is 6 tons per hour. Calculate the following: a. Thermal efficiency of the cycle. b. Power of the turbine. c. Heat removed from steam in the condenser. d. Power of the feed pump, if the water is compressed isentropically. 2. Steam at 20 bar and 300 °C enters a steam turbine-generator unit. The exhaust pressure is 0.06 bar. The steam consumption in the turbine is 6.5-kg/ kWh of the generator output. The combined mechanical and generator efficiency is 84%. What is the condition of steam at the condenser inlet? 3. Steam leaves the boiler of a power plant at 34 bars and 375 °C, and when it enters the turbine it is at 32.5 bars and 350 °C. The turbine efficiency is 85% and the exhaust pressure is 0.12 bar. Condensate leaves the condenser and enters the pump at 0.12 bar and 38 °C. The pump efficiency is 75% and the discharge pressure is 37.5 bars. The feedwater enters the boiler at 36 bars and 36 °C. Calculate: a. The thermal efficiency of the cycle. b. The irreversibility of the process between the boiler exit, and the turbine inlet, assuming an ambient temperature of 25 °C. 4. A steam turbine receives steam at 40 bars and 420 °C. The steam expands with an isentropic efficiency of 75%. When the steam becomes dry saturated it is taken to a reheat section of the boiler, where the temperature is raised to 200 °C. The steam, then, expands to the condenser pressure with an isentropic efficiency of 75% also. Find the reheat pressure, and the amount of reheat given to each kilogram of steam. If the condenser vacuum is 69 cm Hg, calculate the efficiency of the cycle and the power of the turbine for a steam consumption of 20 tons per hour. Calculate also the fuel consumption in the boiler if the C.V. of the fuel is 42,700 kJ/kg, and the boiler efficiency is 88 %. 5. In an 80 MW nuclear power plant, heat is transferred in the reactor to liquid sodium. The liquid sodium is then pumped to a heat exchanger, where heat is transferred to steam. The steam leaves this heat exchanger as saturated vapor at 55 bars, and is then superheated in an external gas-fired superheater to 550 °C. The steam then enters the turbine, which has one extraction point at 4 bars, where steam flows to an open-type feedwater heater. The turbine isentropic efficiency is 80 %, and the condenser pressure
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