A refrigerator operating using vapor-compression cycle uses R-134a as a working fluid. The condenser temperature is 65oC and the evaporator temperature is -15oC. The compressor operates at 80% efficiency. a. Determine the coefficient of performance of the refrigeration cycle. b. How much refrigerant is needed to deliver 3 kW of cooling? c. Sketch the vapor compression cycle indicating the states of each stream (in terms of H, P, T, and S) and showing the values of energy input/output in the system d. Suppose that we replace the expansion valve in the vapor- compression cycle with a turbine that operates at 80% efficiency. Determine the coefficient of performance of the refrigeration cycle. Provide the new state properties (i.e. H, P, T and S) for this changes Please use CATT for any values needed

A refrigerator operating using vapor-compression cycle uses R-134a as a working fluid. The condenser temperature is 65oC and the evaporator temperature is -15oC. The compressor operates at 80% efficiency. a. Determine the coefficient of performance of the refrigeration cycle. b. How much refrigerant is needed to deliver 3 kW of cooling? c. Sketch the vapor compression cycle indicating the states of each stream (in terms of H, P, T, and S) and showing the values of energy input/output in the system d. Suppose that we replace the expansion valve in the vapor- compression cycle with a turbine that operates at 80% efficiency. Determine the coefficient of performance of the refrigeration cycle. Provide the new state properties (i.e. H, P, T and S) for this changes Please use CATT for any values needed

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

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

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