A Food storage locker requires a refrigeration system of 42kW(12TR) capacity at an evaporator temperature of...

A Food storage locker requires a refrigeration system of 42kW(12TR) capacity at an evaporator temperature of -5°C and condenser temperature of 40°C. The refrigerant, R-12, is sub-cooled 5°C before entering the expansion valve, and the vapour is super-heated 6°C before leaving the evaporator coil. The compression of the refrigerant is isentropic. A two-cylinder vertical single acting compressor with stroke equal to 1.5 times the bore is to be used operating at 960 r.p.m. Determine (i) refrigerating effect/kg. (ii) mass of refrigerant per minute, (iii) theoretical suction volume per minute (iv) theoretical power, (vi) COP, (vi) heat removed through condenser/kg and (vii) theoretical bore and stroke of compressor.

Expert Solution

the value of C_p of refrigerant is not given in question so we assume value according to my text book.

samet mamat answered 5 months ago

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