3. A vapour compression refrigerator uses R-12 as refrigerant and the liquid evaporates in the evaporator at - 15 °C. The temperature of this refrigerant at the delivery from the compressor is 15°C when the vapour is condensed at 10°C. Find the coefficient of performance if (i) there is no undercooling , and (ii) the liquid is cooled by 5°C before expansion by throttling. Take specific heat at constant pressure for the superheated vapour as 0.64 kJ/kg.K and for liquid as 0.94 kJ/kg.K. (Same as Example 12)

3. A vapour compression refrigerator uses R-12 as refrigerant and the liquid evaporates in the evaporator at - 15 °C. The temperature of this refrigerant at the delivery from the compressor is 15°C when the vapour is condensed at 10°C. Find the coefficient of performance if (i) there is no undercooling , and (ii) the liquid is cooled by 5°C before expansion by throttling. Take specific heat at constant pressure for the superheated vapour as 0.64 kJ/kg.K and for liquid as 0.94 kJ/kg.K. (Same as Example 12)

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

Chapter50: Commercial, Packaged Rooftop, Variable Refrigerant Flow, And Variable Air Volume Systems

Section: Chapter Questions

Problem 22RQ: Variable refrigerant flow systems sense the ______and _____of the refrigerant to determine the...

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