4- A cascade refrigeration system of 14 TR uses Freon R-12 at -50 °C evaporating temperature and condensing temperature of -15°C with adiabatic compression efficiency of 85 %. The upper cycle uses NH3 with condensing temperature of 37 °C and compression efficiency of 90 %. The temperature difference between the evaporator of the upper cycle and the condenser of the lower cycle is 10 °C. Calculate the power required for each compressor if the mechanical efficiency is 90% and the C.O.P. of the unit.

4- A cascade refrigeration system of 14 TR uses Freon R-12 at -50 °C evaporating temperature and condensing temperature of -15°C with adiabatic compression efficiency of 85 %. The upper cycle uses NH3 with condensing temperature of 37 °C and compression efficiency of 90 %. The temperature difference between the evaporator of the upper cycle and the condenser of the lower cycle is 10 °C. Calculate the power required for each compressor if the mechanical efficiency is 90% and the C.O.P. of the unit.

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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