A vapor compression cycle with R-134a is being used as its refrigerant. The refrigerant leaves the evaporator at -10 C and 120 kPa and it enters the condenser 1.0 MPa. Assuming there is a heat loss due to compression which is equal to 20 kJ/kg, and it has a cooling capacity of 75 tons of refrigeration, Determine the following: (a)heat rejected (b)cooling effect (c)work of compression (d) coefficient of performance (e)volume flow rate of refrigerant (f)compressor discharge temperature

A vapor compression cycle with R-134a is being used as its refrigerant. The refrigerant leaves the evaporator at -10 C and 120 kPa and it enters the condenser 1.0 MPa. Assuming there is a heat loss due to compression which is equal to 20 kJ/kg, and it has a cooling capacity of 75 tons of refrigeration, Determine the following: (a)heat rejected (b)cooling effect (c)work of compression (d) coefficient of performance (e)volume flow rate of refrigerant (f)compressor discharge temperature

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

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 15RQ: Why is two-stage compression popular for extra-low-temperature refrigeration systems?

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Similar questions

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Refrigerant-134a enters the compressor of a cooling system as superheated vapor at 0.18 MPa and 0°C with a flow rate of 0.15 kg/s. It exits the compressor at 0.8 MPa and 60°C. Post compression, the refrigerant is cooled in the condenser to 28°C and 0.7 MPa. Subsequently, it's throttled to 0.16 MPa. Neglecting any heat transfer and pressure drops in the pipelines between the components, represent the cycle on a T-s diagram concerning saturation lines. Calculate: (a) The rate of heat extraction from the cooling area and the energy input to the compressor. (b) The isentropic efficiency of the compressor. (c) The Coefficient of Performance (COP) of the cooling system.
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A real heat pump has .02 kg/s of refrigerant-134a flowing through and consumes 3 kW of power. The refrigerant is a mixture at 50% quality and 120 kPa entering the evaporator and leaves at 100 kPa and -20 C. The refrigerant enters the condenser at 1.4 MPa and leaves at 1.2 MPa. Assuming no loss in pressure or temperature in the connecting pipes, determine the temperature, pressure, enthalpy and entropy at all positions in the cycle, the heat transfer coming in and leaving, the COP of this heat pump, the isentropic efficiency of the compressor, and the rate of entropy generation in the compressor.
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