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 t he t ur bi ne i s i ncr eased t o 5, whi l e maintaining the same inlet conditions. Assume air as a perfect gas with specific heat ratio = 1.4. I f the specific work output remains the same for both the cases, the isentropic efficiency of t he t ur bi ne at t he pr essur e r at i o of 5 is___(round off to two decimal places).

A gas turbine with air as the working fluid has an isentropic efficien

1.	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 t he t ur bi ne i s i ncr eased t o 5, whi l e maintaining the same inlet conditions. Assume air as a perfect gas with specific heat ratio = 1.4. I f the specific work output remains the same for both the cases, the isentropic efficiency of t he t ur bi ne at t he pr essur e r at i o of 5 is___(round off to two decimal places).
A.	5
B.	7
C.	0.51
D.	1
Answer» D. 1

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