A vapour compression refrigeration system using refrigerant F-12 is employed to produce 8640 kg of ice per day. The condensing and evaporating temperature of refrigerant are 48°C and -20°C respectively. Saturated liquid leaves the condenser and saturated vapour leaves the evaporator. Compression is isentropic, water at 35°C is used to form the ice. The temperature of ice should be-8°C. Heat flow into the brine tank from surroundings may be taken as 10% of total heat absorbed from water to form ice. Determine the power required to drive the compressor. Take specific heat of ice = 2.26 kJ/kg-K. Latent heat of ice = 335 kJ/kg. Specific heat of water = 4.2 kJ/kg-K.

A vapour compression refrigeration system using refrigerant F-12 is employed to produce 8640 kg of ice per day. The condensing and evaporating temperature of refrigerant are 48°C and -20°C respectively. Saturated liquid leaves the condenser and saturated vapour leaves the evaporator. Compression is isentropic, water at 35°C is used to form the ice. The temperature of ice should be-8°C. Heat flow into the brine tank from surroundings may be taken as 10% of total heat absorbed from water to form ice. Determine the power required to drive the compressor. Take specific heat of ice = 2.26 kJ/kg-K. Latent heat of ice = 335 kJ/kg. Specific heat of water = 4.2 kJ/kg-K.

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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