In this study, the performance of ejector-expansion refrigeration cycle (EERC) with R134a alternative
refrigerants (R152a, R1234yf, R404A, R407C, R507A and R600a) for automobile airconditioning
application is investigated numerically. The ejector is modeled with a constant
mixing-pressure assumption taking into consideration the friction e®ect in the ejector mixing
section. The studied refrigerants are compared based on the optimum area ratio, discharge
temperature, compressor input power, volumetric cooling capacity, exergy destruction, COP,
exergy e±ciency and COP improvement. The results show that R152a and R1234yf have the
closest performance to R134a and can be considered the most suitable alternative refrigerants for
R134a. The COP and exergy e±ciency are improved by 2.26% and 2.27%, respectively, using
R152a compared to the use of R134a, whereas they are reduced by 2.89% and 2.88% using
R1234yf. The volumetric cooling capacity is reduced for both R152a and R1234yf by 6.14% and
6.8%, respectively. In addition, the e®ect of compressor rotational speed on the performances is
reported.