Q.6 A vapor compression cycle uses R134a as the refrigerant . The vapor condenses at 40 degrees * C and is subcooled to 35 degrees * C before entering the expansion valve . The evaporating temperature is - 5 degrees * C . The vapor leaving the evaporator is superheated to 5 degrees * 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: () 0.0837kg * s ^ - 1 , (ii) 2.63 kW , (iii) 4.95

Q.6 A vapor compression cycle uses R134a as the refrigerant . The vapor condenses at 40 degrees * C and is subcooled to 35 degrees * C before entering the expansion valve . The evaporating temperature is - 5 degrees * C . The vapor leaving the evaporator is superheated to 5 degrees * 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: () 0.0837kg * s ^ - 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

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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