Engineering Board Exam Reviewer · Thermodynamics · medium
In a vapor-compression refrigeration cycle, h at evaporator exit = 390 kJ/kg, h at compressor exit = 425 kJ/kg, and h at condenser exit = 250 kJ/kg. What is the COP?
- 5.00
- 0.25
- 0.92
- 4.00
Answer
D. 4.00
Solution
RE = h1 - h4 = 390 - 250 = 140 kJ/kg (h4 = h3). W = h2 - h1 = 35 kJ/kg. COP = 140/35 = 4.00.
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