EMPIRICAL CORRELATIONS FOR THE PERFORMANCE OF AN AUTOMOTIVE AIR CONDITIONING SYSTEM USING R1234yf AND R134a

A laboratory automotive air conditioning (AAC) system was set up and tested for the cases of employing refrigerants R134a and R1234yf. Two different empirical correlations were developed to predict the steady state performance parameters of the AAC system based on some experimental data. The air stream temperatures entering the evaporator and condenser and the relative humidity of the air stream at the evaporator inlet were selected as the input parameters of the proposed correlations, while the output parameters were the cooling capacity, power absorbed by the refrigerant in the compressor, condenser heat rejection rate, coefficient of performance, conditioned air temperature, compressor discharge temperature and the rate of total exergy destruction in the AAC system. Then, the predictions of these correlations were compared with the experimental results which were not used in developing the correlations. The findings suggest that both correlations can be used for accurately predicting the performance parameters of the AAC systems.