Exergetic Investigation of the Effects of Superheating and Subcooling on Performance of a Vapor Compression Refrigeration Cycle

Abstract

The aim of this study is to investigate the effects of superheating and subcooling values on the cooling performance of a vapor compression refrigeration cycle. For this purpose, a refrigeration cycle with cooling capacity of 8 kW using R404A was examined by changing superheating and subcooling values. Energy, exergy and entropy balances were applied for evaporation and condensation temperatures of 0℃ and 45℃, respectively. In order to evaluate the performance of the refrigeration cycle, coefficient of performance (COP) for cooling, the amount of energy transfer, rate of exergy destruction and rational exergy efficiency of the all components (evaporator, compressor, condenser and expansion valve) and the whole system were determined.

Keywords

• Exergy,Exergy destruction,Refrigeration cycle,Superheating,Subcooling

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