2. A cascade refrigeration system using R - 22 in the low - temperature circuit and ammonia (R-717) in the high temperature circuit has a load of 150 kW. The low - temperature circuit operates at an evaporating temperature of -50°C and a condensing pressure of 500 kPa. Refrigerant leaves the low-temperature evaporator as saturated vapor and enters the suction of the low- temperature compressor at - 45°C. Liquid refrigerant exits the condenser at 02°С. The high temperature circuit - operates at an evaporating temperature of -10°C and a condensing pressure of 1200 kPa. The refrigerant exits both evaporator and condenser at saturated conditions. Calculate the power input to the high temperature circuit - compressor, kW.

2. A cascade refrigeration system using R - 22 in the low - temperature circuit and ammonia (R-717) in the high temperature circuit has a load of 150 kW. The low - temperature circuit operates at an evaporating temperature of -50°C and a condensing pressure of 500 kPa. Refrigerant leaves the low-temperature evaporator as saturated vapor and enters the suction of the low- temperature compressor at - 45°C. Liquid refrigerant exits the condenser at 02°С. The high temperature circuit - operates at an evaporating temperature of -10°C and a condensing pressure of 1200 kPa. The refrigerant exits both evaporator and condenser at saturated conditions. Calculate the power input to the high temperature circuit - compressor, kW.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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