Refrigerant 134a is the working fluid in a vapor-compression heat pump that provides 35 kw to heat a dwelling on a day when the outside temperature is below freezing. Saturated vapor enters the compressor at 1.6 bar, and saturated liquid exits the condenser, which operates at 8 bar. Determine for an isentropic compressor efficiency of 85%: (a) the refrigerant mass flow rate, in kg's. (b) the magnitude of the compressor povwer, in kW. (c) the coefficient of performance.

Refrigerant 134a is the working fluid in a vapor-compression heat pump that provides 35 kw to heat a dwelling on a day when the outside temperature is below freezing. Saturated vapor enters the compressor at 1.6 bar, and saturated liquid exits the condenser, which operates at 8 bar. Determine for an isentropic compressor efficiency of 85%: (a) the refrigerant mass flow rate, in kg's. (b) the magnitude of the compressor povwer, in kW. (c) the coefficient of performance.

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

Chapter41: Troubleshooting

Section: Chapter Questions

Problem 8RQ: When the outside ambient air temperature is 90F, the temperature of the condensing refrigerant in a...

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