Experimental Comparative energy, exergy flow and second law efficiency analysis of R22, R436b vapour compression refrigeration cycles

This study presents an experimental comparison of energy, exergy flow and second law efficiency of R22 and its substitute R436b (hydrocarbon mixture of 52% of propane (R290) 48% of isobutene (R600a)), vapour compression refrigeration cycles. The vapour compression refrigeration cycle was initially designed to operate with R22. The primary objective of this paper is to analyze the system processes separately and to identify and quantify the sites having largest energy and exergy flow losses .In addition the effect of various reference environment state on this analysis also presented .The exergy efficiency of the cycle is defined as the exergy flow rate in the evaporator to the isentropic compressor work. And second law efficiency is defined as the ratio of actual COP to the Carnot COP. Change in exergy flow rate, the exergy efficiency of components and piping of actual VCRC’s have been carried out under different evaporator temperature for both the cycles. The exergy flow of various points on vapour compression refrigeration cycle i.e. from 1-2, 2-3, 3-4, 4-5, and 5-1, exergy efficiency and second law efficiency for both R 22 and R436b refrigeration cycles are compared. Results have been presented graphically that shows the location of in efficiencies.