Experimental Study on the Performance of Dual-Evaporator Refrigeration System with an Ejector

Experimental investigation on the performance of dual-evaporator refrigeration system with an ejector has been carried out In this study, HFC-134a is chosen as a working fluid. Test setup is composed of compressor, condenser, expansion valves, two evaporators, and ejector which is installed between two evaporators. The condenser and two evaporators are made as concentric counter-flow type heat exchangers. Experiments are performed by changing the inlet and outlet temperatures of secondary fluids entering the condenser, high-pressure evaporator and low-pressure evaporator at constant compressor speed condition. When the external conditions are fixed, results show that coefficient of performance (COP) increases as the inlet temperature of the other evaporator becomes higher. It is also shown that the COP decreases as entrainment ratio of the ejector increases. For the same conditions, the COP of dual-evaporator refrigeration system with an ejector is superior to that of the singleevaporator vapor compression system by 3 to 6%.