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b) Air enters the compressor of a gas turbine plant operating on Brayton cycle at 1 bar, 30°C.
The pressure ratio in the cycle is 7. Calculate the maximum temperature in the cycle and the
cycle efficiency. Assume turbine work is 2.5 times the compressor work. Take the ratio

of specific heats as 1.4. (6 marks)

13. Air enters the compressor of an open cycle constant pressure gas turbine at a pressure of | bar
and temperature of 30°C. The pressure of the air after compression is 5 bar. The isentropic
efficiencies of compressor and turbine are 80% and 85% respectively. The air-fuel ratioused is
80:1. If the flow rate of air is 3.0 kg/s, find: (i) Power developed. (ii) Thermal efficiency of the
cycle. Take calorific value of fuel as 42000 kJ/kg. Assume cp = 1.005 kJ/kg K and y = 1.4 for
air and gases. (10 marks)

14. (a) Explain three methods for the improvement of efficiency of open cycle gas turbine power
plant with necessary T&S diagrams. )6 marks)

b) Derive impression for efficiency of ideal Joule Cycle. (4 marks)

TRB RR

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