Energetic and Exergetic analysis of R22 and R134 refrigerants as working fluids in a multipurpose domestic refrigeration system

Abstract

The performance of a domestic refrigeration system was measured by its coefficient of performance (COP), volumetric cooling capacity, cooling capacity, condenser capacity, and input power to compressor, discharge temperature, pressure ratio and refrigerant mass flow rate. Nowadays, a new characteristic has been added to the list to define the performance of the system. That new trend is the exergy destructed by the system. Nevertheless, considering the impact of the refrigerant being used to the environment is not to be neglected. Hydrocarbon refrigerants such as R22 and R134a have been proven to be good performing in domestic refrigeration systems. Both of these two possess an Ozone Depletion Potential (ODP) as well as a Global Warning potential good (GWP) enough to be said eco-friendly. The refrigerant R22 is having an ODP of 0.055 and a GWP of 1500 (100 years). And when it comes to R134a, it has an ODP of 0 and a GWP of 1200 (100 years). These are one of the reason why they are being used worldwide. Besides, R22 and R134a have shown satisfactory result in term of energy and exergy analysis when used to a simple vapor compression refrigeration system. A multipurpose refrigeration system allows to get a system with two different cooling space. One space that would cool goods and keep them around 5 degree Celsius, and a second space that makes formation of ice from water and to freeze good to be possible and will have a temperature of approximatively -5 to -10 A study of a VCR system using each of these named refrigerants yielded to some appreciable result in term of energy, mainly C.O.P, and exergy analysis. Using, again, a multipurpose refrigeration system with a single compressor, R22 and R134a have presented satisfactory results with an acceptable cooling rate. However, both refrigerants have shown good performances, but it is found that R134a has presented better C.O.P than R22.