Engineering Board Exam Reviewer · Thermodynamics · hard
An ideal Brayton cycle has a compressor inlet temperature of 300 K, a pressure ratio of 8, and a turbine inlet temperature of 1300 K. What is the net work per kg of air? (cp = 1.0 kJ/kg· K, k = 1.4)
- 582.3 kJ/kg
- 243.4 kJ/kg
- 825.8 kJ/kg
- 338.9 kJ/kg
Answer
D. 338.9 kJ/kg
Solution
T2 = 300(8)0.2857 = 543.4 K; T4 = 1300/(8)0.2857 = 717.7 K. wT = 582.3, wC = 243.4. wnet = 338.9 kJ/kg.
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