Comparative Evaluation of an Automobile Air - Conditioning System Using R134a and Its Alternative Refrigerants

This research involves the theoretical aspects of R134a automobile air conditioning system. The main aim of the research is to evaluate the different alternative refrigerants as a drop in substitute of R134a theoretically. For this purpose, thermodynamic properties of different alternative refrigerants i.e. R290, R600a, R407C, R410A, R404A, R152a and R1234yf are compared to R134a. Thermodynamic evaluation of standard rating cycle of vapour compression refrigeration system is carried out. Engineering equation solver and refprop soft wares have been used for the thermodynamic analysis purpose. From thermodynamic analysis, it is derived that R1234yf is best suitable alternative refrigerants as a drop in substitute of R134a. R1234yf has lower coefficient of performance as compared to R134a; however it is best suitable alternative refrigerants as a drop in substitute because it has very low global warming potential and can be substituted in the existing automobile air conditioning system with minimum modification.