Avapor-compression heat pump has a heating capacity of 500 kl/min and uses Refrigerant 134a asthe workingfluid. The isentropic compressor efficiency is 75%. The heat pump isdriven by a power cyclewith a thermal efficiency of 25%. Forthe power cycle, 80% of the heat rejected istransferred to the heated space. Data for thecycle are provided in thetable below. The principal states are numbered as in the figure below. Condenser Expansion valve Compressor Evaporator Saturated or superheated vapor 5 State (baг) (°C) (k/kg) (kJ/kg -K) 1 4.145 10 252.9 0.9141 25 10 42.02 271 0.9141 2 10 47.26 277.1 0.9331 3 9.6 34 97.31 0.3584 4 4.145 10 97.31 0.3645 (a) Determinethe power input to the heat pump compressor, in kW. (b) Evaluate theratio of the total ratethat heat is delivered to the heated spaceto the rateof heat inputto the power cycle.

Avapor-compression heat pump has a heating capacity of 500 kl/min and uses Refrigerant 134a asthe workingfluid. The isentropic compressor efficiency is 75%. The heat pump isdriven by a power cyclewith a thermal efficiency of 25%. Forthe power cycle, 80% of the heat rejected istransferred to the heated space. Data for thecycle are provided in thetable below. The principal states are numbered as in the figure below. Condenser Expansion valve Compressor Evaporator Saturated or superheated vapor 5 State (baг) (°C) (k/kg) (kJ/kg -K) 1 4.145 10 252.9 0.9141 25 10 42.02 271 0.9141 2 10 47.26 277.1 0.9331 3 9.6 34 97.31 0.3584 4 4.145 10 97.31 0.3645 (a) Determinethe power input to the heat pump compressor, in kW. (b) Evaluate theratio of the total ratethat heat is delivered to the heated spaceto the rateof heat inputto the power cycle.

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 12RQ: Refrigerators currently being manufactured in the United States are using______as their refrigerant.

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