As the refrigerant as shown in the figure, R134a fluid is used in acommercial refrigerator. The refrigerant exits the evaporator at atemperature of -33.5°C (239.65 K) and a pressure of 60 kPa. It is thencompressed to a pressure of 1.2 MPa and a temperature of 64°C (337.15K). In the water-cooled condenser, the refrigerant is cooled to 41°C(314.15 K). Water enters the condenser at 18°C and leaves at 26°C. Inthis context;water32cooler|liquidcondenserexpansioncompressora) Determine the entropy generation currents in [kW/K] and the exergydestruction currents in [kW] for the evaporator, compressor, condenserand expansion valve.b) Calculate the degree of dryness (quality) of the refrigerant at theevaporator inlet [%].c) Determine the cooling load [kW].d) Calculate the COP value and the maximum (maximum) COP value ofthe refrigeratorvalve vaporizer

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commercial refrigerator. The refrigerant exits the evaporator at a temperature of -33.5°C (239.65 K) and a pressure of 60 kPa. It is then compressed to a pressure of 1.2 MPa and a temperature of 64°C (337. K). In the water-cooled condenser, the refrigerant is cooled to 41°C (314.15 K). Water enters the condenser at 18°C and leaves at 26°C. In this context; a) Determine the entropy generation currents in [kW/K] and the exerg destruction currents in [kW] for the evaporator, compressor, condense= and expansion valve. b) Calculate the degree of dryness (quality) of the refrigerant at the evaporator inlet [%]. c) Determine the cooling load [kW]. d) Calculate the COP value and the maximum (maximum) COP value

commercial refrigerator. The refrigerant exits the evaporator at a temperature of -33.5°C (239.65 K) and a pressure of 60 kPa. It is then compressed to a pressure of 1.2 MPa and a temperature of 64°C (337. K). In the water-cooled condenser, the refrigerant is cooled to 41°C (314.15 K). Water enters the condenser at 18°C and leaves at 26°C. In this context; a) Determine the entropy generation currents in [kW/K] and the exerg destruction currents in [kW] for the evaporator, compressor, condense= and expansion valve. b) Calculate the degree of dryness (quality) of the refrigerant at the evaporator inlet [%]. c) Determine the cooling load [kW]. d) Calculate the COP value and the maximum (maximum) COP value

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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A vapor compression refrigeration cycle uses refrigerant-134a as its working fluid. The condenser pressure is 800 kPa and the evaporator temperature is -20 C. The compressor has an isentropic efficiency of 80 percent. The mass flow rate is 1.0493 kg/s. The enthalpy at the isentropic exit state of the compressor is h2s = 271.9 kJ/kg. In the question that follows, select the answer that is closest to the true value. What is the power going to the compressor in units of kW?
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