Variation of Performance of Refrigeration System at different Temperature

In this paper, the performances of four ozone-friendly Hydrofluorocarbon (HFC) refrigerants (R125, R134a, R143a and R152a) selected to replace R12 in a vapour compression refrigeration system were investigated experimentally and compared. The performance in term of coefficient of performance (COP), refrigerating capacity (RC), and compressor work (We) were evaluated for the investigated refrigerants at various evaporating and condensing temperatures. The system performance increases as the evaporating temperature increases, but reduces as the condensing temperature increases. The results obtained showed that the investigated refrigerants confirmed that R152a and R134a have approximately the same thermodynamic performances similar to R12 while deviation of R125 and R143a were very large. But the best performance was obtained from the used of R152a in the system. As a result, R152a could be used as a drop-in replacement for R134a in vapour compression refrigeration system. The COP of R152a obtained was higher than those of R12, R125, R134a, R143a. Also, R152a offers the best desirable environmental requirements; zero Ozone Depleting Potential (ODP) and very low Global Warming Potential (GWP).