A heat pump uses R-134a as the refrigerant. The refrigerant enters the adiabatic compressor as saturated vapor at 120 kPa and exits it (the compressor) at 800 kPa and 50°C. The refrigerant exits the condenser as saturated liquid at 800 kPa. Then, the refrigerant flows through an adiabatic expansion valve, reducing the pressure back to the evaporator pressure of 120 kPa. The compressor power is 1.25 kW. a) Calculate the mass flow rate of the refrigerant (R-134a) in kg/s or g/s. b) Calculate the heat power delivered from the condenser in kW. c) Calculate the coefficient of performance (COP) of the heat pump, COP_HP.d) Calculate the refrigerant’s vapor quality entering the evaporator.

A heat pump uses R-134a as the refrigerant. The refrigerant enters the adiabatic compressor as saturated vapor at 120 kPa and exits it (the compressor) at 800 kPa and 50°C. The refrigerant exits the condenser as saturated liquid at 800 kPa. Then, the refrigerant flows through an adiabatic expansion valve, reducing the pressure back to the evaporator pressure of 120 kPa. The compressor power is 1.25 kW. a) Calculate the mass flow rate of the refrigerant (R-134a) in kg/s or g/s. b) Calculate the heat power delivered from the condenser in kW. c) Calculate the coefficient of performance (COP) of the heat pump, COP_HP.d) Calculate the refrigerant’s vapor quality entering the evaporator.

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 13RQ: Condensers in these refrigerators are all_______cooled.

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