Consider a two-stage cascade refrigeration system operating between 0.1MPa and 1MPa. Each stage operates on the ideal cycle with R-134a as the working fluid. Heat rejection from the lower to the upper cycle occurs at 0.4MPa. If the mass flow rate in the upper cycle is 0.1 kg/s, Determine: (a) the mass flow rate through the lower cycle and (b)the COP.

Consider a two-stage cascade refrigeration system operating between 0.1MPa and 1MPa. Each stage operates on the ideal cycle with R-134a as the working fluid. Heat rejection from the lower to the upper cycle occurs at 0.4MPa. If the mass flow rate in the upper cycle is 0.1 kg/s, Determine: (a) the mass flow rate through the lower cycle and (b)the COP.

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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