An ideal vapor-compression refrigeration cycle with refrigerant-134a as the working fluid operates between pressure limits of 200 and 1600 kPa. The refrigerant absorbs heat from a space at 3°C and rejects heat to ambient air at 27 °C. Determine (a) the heat absorbed in the evaporator and the work input, (b) the COP, (c) the exergy destruction in each component of the cycle and the total exergy destruction in the cycle, (d) the second-law efficiency of the cycle.

An ideal vapor-compression refrigeration cycle with refrigerant-134a as the working fluid operates between pressure limits of 200 and 1600 kPa. The refrigerant absorbs heat from a space at 3°C and rejects heat to ambient air at 27 °C. Determine (a) the heat absorbed in the evaporator and the work input, (b) the COP, (c) the exergy destruction in each component of the cycle and the total exergy destruction in the cycle, (d) the second-law efficiency of the cycle.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 15RQ: Why is two-stage compression popular for extra-low-temperature refrigeration systems?

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