Experimental study on two-stage ejector refrigeration system driven by two heat sources

In this paper, an experimental study on a two-stage ejector refrigeration system driven by two heat sources is carried out involving system design, setup, operation and experimental evaluation. It is looked at by means of changing temperatures of evaporation, condensation, low and high temperature generation independently for the variation tendency of system performance (including total entrainment ratio and COP) and comparison to the conventional single-stage ejector refrigeration system at variable condensation temperatures that is achieved by the valve switching in this system. In terms of refrigerants, R236fa is selected for stability of the system operation. Total entrainment ratio and COP are increasing as the temperatures of evaporation, high and low temperature generation go up. Different from the conventional single-stage ejector refrigeration system, this two-stage system is finally found to be capable of supplying more refrigerating effect in situations where the condensation temperature is lower than 21.7 °C.