Engineering Board Exam Reviewer · Thermodynamics · hard
Air enters a compressor at 300 K and is compressed with a pressure ratio of 8. The actual exit temperature is 590 K. What is the isentropic efficiency of the compressor? (k = 1.4)
- 119.13%
- 92.11%
- 83.94%
- 50.85%
Answer
C. 83.94%
Solution
T2s = 300(8)0.2857 = 543.4 K. C = (T2s - T1)/(T2 - T1) = 243.4/290 = 83.94%.
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