The vapour compression cycle (picture provided), utilises the refrigerant R134a flowing at 0.05 kg s-1. Assuming that the compression is adiabatic and reversible. If the actual input power to the compressor is 2 kW, then: 1. You need to determine the theoretical input power to the compressor and the heat transfer (Φ) to the evaporator. Take the enthalpies h1, h2, and h3 to be 238.41, 263.68 and 81.5 kJ kg-1 (use the 'NH3 Refrigeration Table' where you can find online). 2. You need to determine the coefficient of performance based on your answer to the previous question (1). 3. You need to determine the compressors mechanical efficiency.

The vapour compression cycle (picture provided), utilises the refrigerant R134a flowing at 0.05 kg s-1. Assuming that the compression is adiabatic and reversible. If the actual input power to the compressor is 2 kW, then: 1. You need to determine the theoretical input power to the compressor and the heat transfer (Φ) to the evaporator. Take the enthalpies h1, h2, and h3 to be 238.41, 263.68 and 81.5 kJ kg-1 (use the 'NH3 Refrigeration Table' where you can find online). 2. You need to determine the coefficient of performance based on your answer to the previous question (1). 3. You need to determine the compressors mechanical efficiency.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.27P

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