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R-134a enters the compressor of a refrigerator as superheated vapour at 0.14 MPa, -10 °C at...

R-134a enters the compressor of a refrigerator as superheated vapour at 0.14 MPa, -10 °C at a rate of 0.12 kg/s, and it leaves at 0.7 MPa and 50 °C.
The refrigerant is cooled in the condenser to 24 °C and 0.65 MPa, and it is throttled to 0.15 MPa.
Disregard any heat transfer and pressure drops in the connecting lines between the components.

Show the cycle on a T-s diagram with respect to saturation lines, and determine
(a) the rate of heat removal from the refrigerated space and the power input to the compressor,
(b) the isentropic efficiency of the compressor
(c) the COP of the refrigerator

A company claims they can raise the COP of the refrigerator to 4.8 by reducing heat transfer and pressure drops in the compressor only.
(d) Show if it is possible by calculation

Science   Advanced-Physics   
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