Air enters the compressor of an ideal Brayton refrigeration cycle at 100 kPa, 270 K. The compressor pressure ratio is 3 and the temperature at the turbine inlet is 310 K. Determine: d).the coefficient of performance of a Carnot refrigeration cycle operating between thermal reservoirs at TC 270 K and TH 310 K, respectively. The above 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: (e).the lowest temperature, in K. f).the net work input per unit mass of air flow, in kJ / kg

Air enters the compressor of an ideal Brayton refrigeration cycle at 100 kPa, 270 K. The compressor pressure ratio is 3 and the temperature at the turbine inlet is 310 K. Determine: d).the coefficient of performance of a Carnot refrigeration cycle operating between thermal reservoirs at TC 270 K and TH 310 K, respectively. The above 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: (e).the lowest temperature, in K. f).the net work input per unit mass of air flow, in kJ / kg

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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