A simple vapor compression cycle uses ammonia as a refrigerant. The vaporizing and condensing temperature are -20°C and 35°C, respectively. The system is to be used in producing 10,000 kg of ice at -15°C from water at 25°C in 25 hours. The specific heat of ice is 2.094 kJ/kg-K and the heat of fusion is 335 kJ/kg. Assume that there are 30 percent losses of the heat to be absorbed from the water. Determine the mass of the refrigerant that circulates in the system in kg/s. (Use h₂ = 1735 kJ/kg)

A simple vapor compression cycle uses ammonia as a refrigerant. The vaporizing and condensing temperature are -20°C and 35°C, respectively. The system is to be used in producing 10,000 kg of ice at -15°C from water at 25°C in 25 hours. The specific heat of ice is 2.094 kJ/kg-K and the heat of fusion is 335 kJ/kg. Assume that there are 30 percent losses of the heat to be absorbed from the water. Determine the mass of the refrigerant that circulates in the system in kg/s. (Use h₂ = 1735 kJ/kg)

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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