PROBLEM 20:In a conventional refrigeration cycle which uses Freon-12 as the refrigerant, the temperature of the evaporating fluid is -20°C. It leaves the evaporator as saturated vapor at -20°C and enters the compressor. The pressure in the condenser is 1.30 MPa. The liquid leaves the condenser and enters the expansion valve at 40°C. It is proposed to modify this cycle by adding a heat exchanger that would superheat the suction vapor to 25°C. 2.1 Compare the coefficient of performance of these two cycles. 2.2 What is the temperature of the refrigerant entering the expansion valve with the heat exchanger? 2.3 For a load of 50 kW, determine the volume flow rate for both cycles.

PROBLEM 20:In a conventional refrigeration cycle which uses Freon-12 as the refrigerant, the temperature of the evaporating fluid is -20°C. It leaves the evaporator as saturated vapor at -20°C and enters the compressor. The pressure in the condenser is 1.30 MPa. The liquid leaves the condenser and enters the expansion valve at 40°C. It is proposed to modify this cycle by adding a heat exchanger that would superheat the suction vapor to 25°C. 2.1 Compare the coefficient of performance of these two cycles. 2.2 What is the temperature of the refrigerant entering the expansion valve with the heat exchanger? 2.3 For a load of 50 kW, determine the volume flow rate for both cycles.

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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