An open-cycle gas turbine plant is used to genera e power in an oil refinery. The gas turbine unit drives a generator that supplies electric motors of 2400 kW; the overall mechanical and electrical efficiency is 92%. Some of the exhaust gas from the turbines at 530 C is supplied to a furnace in the refinery at a rate of 2 kg/s; the remainder of exhaust gas is passed in counterflow through a heat exchanger where it heats the air leaving the compressor, and then passes to exhaust at 400 c. The compressor has a pressure ratio of 8 and The air entry is at 1.013 bar and 20 C. The pressure loss in the airside of the heat exchanger is 0.16 bar, the pressure loss in the combustion chamber is 0.12 bar, and the pressure loss in the gas side of the heat exchanger is 0.05 bar. The isentropic efficiencies of the compressor and turbine are 0.85 and 0.92 respectively. Neglecting heat losses in the heat exchanger, and the mass flow of fuel, calculate:
(i) the mass flow rate of air entering the compressor.
(ii) the temperature of the air entering the compressor;
(iii) the overall cycle efficiency.

Answer rating: 100% (QA)

NOTE Tempera... View the full answer