The A 5000 kW gas-turbine power plant operates with a low-pressure compressor and a high-pressure one...

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The A 5000 kW gas-turbine power plant operates with a low-pressure compressor and a high-pressure one with intercooling stage between them. The overall pressure ratio is 9. A high-pressure turbine is used to drive the compressor, and a low-pressure one drives the electrical generator. temperature of the gases at entry to the high-pressure turbine is 750 °C, and the gases are reheated to 750 °C after expansion in the first turbine. The exhaust gases leaving the low-pressure turbine are passed through a heat exchanger to heat the air leaving the high-pressure compressor. The intercooler is ideal, and the air inlet temperature to the unit is 27 °C. The isentropic efficiency of each compressor is 0.85 and that of each turbine is 0.87. The heat exchanger thermal ratio is 0.75. A mechanical efficiency of 0.95 may be assumed for both the power shaft and the compressor-turbine shaft. For air; cp=1.005 kJ/kg K and y = 1.4, and for products of combustion; Cp = 1.15 kJ/kg K and y= 1.333. Neglecting the effect of fuel mass, determine the mass flow rate of the air and the thermal efficiency of the cycle The A 5000 kW gas-turbine power plant operates with a low-pressure compressor and a high-pressure one with intercooling stage between them. The overall pressure ratio is 9. A high-pressure turbine is used to drive the compressor, and a low-pressure one drives the electrical generator. temperature of the gases at entry to the high-pressure turbine is 750 °C, and the gases are reheated to 750 °C after expansion in the first turbine. The exhaust gases leaving the low-pressure turbine are passed through a heat exchanger to heat the air leaving the high-pressure compressor. The intercooler is ideal, and the air inlet temperature to the unit is 27 °C. The isentropic efficiency of each compressor is 0.85 and that of each turbine is 0.87. The heat exchanger thermal ratio is 0.75. A mechanical efficiency of 0.95 may be assumed for both the power shaft and the compressor-turbine shaft. For air; cp=1.005 kJ/kg K and y = 1.4, and for products of combustion; Cp = 1.15 kJ/kg K and y= 1.333. Neglecting the effect of fuel mass, determine the mass flow rate of the air and the thermal efficiency of the cycle