Experimental investigations on a R134a ejector applied in a refrigeration system

Abstract

An experimental investigation on the performance of an ejector applied in a refrigeration system is conducted. The system uses R134a as a working fluid. The experimental results indicate that back pressure plays an important role in the entrainment ratio of an ejector because this parameter determines the operation mode of an ejector under certain primary fluid pressure and secondary fluid pressure. Increasing in the primary fluid pressure can improve the critical back pressure while deteriorate the best performance of an ejector. Moreover, an optimal value of the primary fluid pressure exists corresponding to a maximum value of the entrainment ratio under a given condition. A logarithmic relation is developed to predict the critical back pressure and to determine operating conditions in a R134a ejector refrigeration system. The research findings will be meaningful for researchers to have a better understanding of the R134a ejector applied in a refrigeration system.