A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°C by rejecting waste heat to cooling water that enters the condenser at 18°C at a rate of 0.35 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 50°C and leaves at the same pressure subcooled by 5°C. The compressor consumes 3.3 kW of power. Use data from the tables. 26°C 4 1.2 MPa 5°C subcooled Expansion valve Condenser Evaporator PL Water 18°C 1.2 MPa 50°C Compressor Determine the COP of the refrigerator. The COP of the refrigerator is

A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°C by rejecting waste heat to cooling water that enters the condenser at 18°C at a rate of 0.35 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 50°C and leaves at the same pressure subcooled by 5°C. The compressor consumes 3.3 kW of power. Use data from the tables. 26°C 4 1.2 MPa 5°C subcooled Expansion valve Condenser Evaporator PL Water 18°C 1.2 MPa 50°C Compressor Determine the COP of the refrigerator. The COP of the refrigerator is

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

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

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A refrigeration system operates on an ideal vapor compression using R-12 with an evaporator temperature of -30 C and a condenser exit temperature of 49.30C and requires 74.6 kW motor to drive the compressor. What is the capacity of the refrigerator in tons of refrigeration? Enthalpy at the condenser ,entrance = 382KJ/Kg, exit = 248.15KJ/Kg, at evaporator entrance= 248.15kJ/kg, exit =338.14kJ/kg.
1. A refrigeration system operates on an ideal vapor compression using R-12 with an evaporator temperature of -30°C and condenser exit temperature of 49 30 °C and requires 74.6 kW motor to drive the compressor. What is the capacity of the refrigerator in tons of refrigeration? Enthalpy at condenser entrance = 382 kJ/kg, exit = 248.15 kJ/kg, at evaporator entrance 248.15 KJ/kg, exit = 338.14 kJ/kg.