An ammonia ice plant operates between a condenser temperature of 35oC and evaporator of –15oC. It produces 10 metric tons of ice per day from water at 30oC to ice at –5oC. Assuming simple saturation cycle, determine the horsepower of the motor if the adiabatic efficiency of the compressor ηc = 0.80 and mechanical efficiency ηm = 0.90. The specific heat of ice is 2.094 kJ/kg.oC and the latent heat is 335 kJ/kg. From the table for ammonia the following enthalpies are: condenser entrance = 1703 kJ/kg, exit = 366.1 kJ/kg; compressor entrance = 1443.9 kJ/kg, exit = 1703 kJ/kg A. 14.55 hp B. 24.55 hp C. 34.55 hp D. 44.55 hp

An ammonia ice plant operates between a condenser temperature of 35oC and evaporator of –15oC. It produces 10 metric tons of ice per day from water at 30oC to ice at –5oC. Assuming simple saturation cycle, determine the horsepower of the motor if the adiabatic efficiency of the compressor ηc = 0.80 and mechanical efficiency ηm = 0.90. The specific heat of ice is 2.094 kJ/kg.oC and the latent heat is 335 kJ/kg. From the table for ammonia the following enthalpies are: condenser entrance = 1703 kJ/kg, exit = 366.1 kJ/kg; compressor entrance = 1443.9 kJ/kg, exit = 1703 kJ/kg A. 14.55 hp B. 24.55 hp C. 34.55 hp D. 44.55 hp

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 12RQ: Refrigerators currently being manufactured in the United States are using______as their refrigerant.

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An ammonia ice plant operates between a condenser temperature of 35°C and evaporator of -15°C. It produces 10 metric tons of ice per day from water at 30°C to ice at -5°C. Assuming simple saturation cycle, determine the horsepower of the motor if the adiabatic efficiency of the compressor nc = 0.85 and mechanical efficiency nm = 0.95. The specific heat of ice is 2.094 kJ/kg-°C and the latent heat is 335 kJ/kg. From the table for ammonia the following enthalpies are: condenser entrance = 1703 kJ/kg, exit = 366.1 kJ/kg; compressor entrance = 1443.9 kJ/kg, exit = 1703 kJ/kg.
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