Brayton refrigeration cycle is modified by introducing a regenerative heat exchanger. In the modified cycle, the compressed air enters the regenerative heat exchanger at 310 K and is cooled to 280 K before entering the turbine. Determine for the modified cycle: f).the net work input per unit mass of air flow, in kJ / kg. g).the cooling capacity, per unit mass of air flow, in kJ / kg. h).the coefficient of performance.

Brayton refrigeration cycle is modified by introducing a regenerative heat exchanger. In the modified cycle, the compressed air enters the regenerative heat exchanger at 310 K and is cooled to 280 K before entering the turbine. Determine for the modified cycle: f).the net work input per unit mass of air flow, in kJ / kg. g).the cooling capacity, per unit mass of air flow, in kJ / kg. h).the coefficient of performance.

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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