The figure below shows a two-stage vapor-compression refrigeration system with ammonia as the working fluid. The system uses a direct-contact heat exchanger to achieve intercooling. The evaporator has a refrigerating capacity of 40 tons and produces -30°F saturated vapor at its exit. In the first compressor stage, the refrigerant is compressed adiabatically to 140 lbf/in.², which is the pressure in the direct contact heat exchanger. Saturated vapor at 140 lbf/in² enters the second compressor stage and is compressed adiabatically to 250 lbf/in.2 Each compressor stage has an isentropic efficiency of 85%. There are no significant pressure drops as the refrigerant passes through the heat exchangers. Saturated liquid enters each expansion valve.

The figure below shows a two-stage vapor-compression refrigeration system with ammonia as the working fluid. The system uses a direct-contact heat exchanger to achieve intercooling. The evaporator has a refrigerating capacity of 40 tons and produces -30°F saturated vapor at its exit. In the first compressor stage, the refrigerant is compressed adiabatically to 140 lbf/in.², which is the pressure in the direct contact heat exchanger. Saturated vapor at 140 lbf/in² enters the second compressor stage and is compressed adiabatically to 250 lbf/in.2 Each compressor stage has an isentropic efficiency of 85%. There are no significant pressure drops as the refrigerant passes through the heat exchangers. Saturated liquid enters each expansion valve.

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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