Özet:

In this study, the performances of the R417A, R438A, R422A and R422D refrigerants which are alternative to the commonly used and ozone layer-friendly R22 refrigerant are examined according to the first and second law of thermodynamics. Chemours Refrigerant Expert 1.0 and Genetron Properties 1.4 were used for the design of the vapor compression cycle. While the condensing temperature was kept constant during the analyses, the evaporation temperatures were determined according to the EUROVENT conditions (0 °C, -8 °C, -25 °C, -31 °C). The parameters calculated according to different evaporation temperatures are the required compressor power, performance coefficient (COP), and the required refrigerant mass flow rate. The results showed that the COP values of the R438A and R417A refrigerants were very close to that of R22. The COP values were 5%, 6%, 15% and 10% lower in R438A, in R471A, in R422A, and in R422D, respectively compared to the R22 refrigerant. The COP values were calculated as 13% for R422D and 17% for R422A. The highest exergy efficiency of the analyzed systems was calculated as 31.74% for R438A, 31% for R417A, 27.46% for R422A, and 29.24% for R422D at -25°C evaporation temperature. The results of our study revealed that among the R417A, R438A, R422A and R422D refrigerants developed as an alternative to R22 refrigerant, the R438A refrigerant had comparatively higher COP values. Also, when the condenser and compressor loads were examined, it was found that the R438A, R417A, R422D and R422A refrigerants yielded the best results, respectively. Among the four alternative refrigerants examined, R438A and R417A were found to be better alternatives to R22 in terms of COP values, exergy efficiency, and exergy destruction.

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