The compression efficiency is fairly constant at 82%. A compressor in this line has two cylinders, each having a 92 mm bore and a S= 74 mm stroke. The compressor has 4.5% clearance and operates at N = 28 rev/s. The system is being selected for an A/C unit and will operate between an evaporating temperature of 0 °C and a condensing temperature of 35 °C. There is 5 °c of sub-cooling in the condenser, and 10 °C of superheating in the evaporator. a. Sketch and label all state points of the system on a NH3 p-h chart (attach to this cover sheet) b. Compute the refrigerant flow rate (kg/sec) c. Compute the refrigerating capacity (kW) d. Determine the compressor motor size (kW)

The compression efficiency is fairly constant at 82%. A compressor in this line has two cylinders, each having a 92 mm bore and a S= 74 mm stroke. The compressor has 4.5% clearance and operates at N = 28 rev/s. The system is being selected for an A/C unit and will operate between an evaporating temperature of 0 °C and a condensing temperature of 35 °C. There is 5 °c of sub-cooling in the condenser, and 10 °C of superheating in the evaporator. a. Sketch and label all state points of the system on a NH3 p-h chart (attach to this cover sheet) b. Compute the refrigerant flow rate (kg/sec) c. Compute the refrigerating capacity (kW) d. Determine the compressor motor size (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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