A gas turbine with air as the working fluid has an isentropic efficiency of 0.70 when operating at a pressure ratio of 3

Q. A gas turbine with air as the working fluid has an isentropic efficiency of 0.70 when operating at a pressure ratio of 3. Now, the pressure ratio of the turbine is increased to 5, while maintaining the same inlet conditions. Assume air as a perfect gas with specific heat ratio g = 1.4 . If the specific work output remains the same for both the cases, the isentropic efficiency of the turbine at the pressure ratio of 5 is    (round off to two decimal places)

Ans: 0.514

Sol:

Consider it is asked only for turbine portion as for full cycle,data is not sufficient