Q.6 A vapor compression cycle uses R134a as the refrigerant. The vapor condenses at 40°C and is subcooled to 35°C before entering the expansion valve. The evaporating temperature is -5°C. The vapor leaving the evaporator is superheated to 5°C at entry to the compressor. The heat absorption rate is 13 kW and the compression process is isentropic. Calculate (i) the refrigerant flow rate, (ii) the work input, and (iii) the COP. [Answers: (i) 0.0837 kgs ¹, (ii) 2.63 kW, (iii) 4.95

Q.6 A vapor compression cycle uses R134a as the refrigerant. The vapor condenses at 40°C and is subcooled to 35°C before entering the expansion valve. The evaporating temperature is -5°C. The vapor leaving the evaporator is superheated to 5°C at entry to the compressor. The heat absorption rate is 13 kW and the compression process is isentropic. Calculate (i) the refrigerant flow rate, (ii) the work input, and (iii) the COP. [Answers: (i) 0.0837 kgs ¹, (ii) 2.63 kW, (iii) 4.95

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 19RQ: Two methods used to power refrigeration compressors on a ship are _____and ____.

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