Experimental investigation on the effect of evaporator design and application of work recovery on the performance of two-phase ejector liquid recirculation cycles with R410A

Abstract In this paper, vapor-compression cycles using the work recovered by an ejector to provide liquid recirculation are investigated experimentally with R410A. The ejector recirculation cycle, in which the ejector is used to recirculate liquid through the evaporator but not directly increase compressor suction pressure, and the standard two-phase ejector cycle, in which the ejector can directly unload the compressor and recirculate liquid, are compared to each other and to a baseline DX cycle without an ejector. The comparison is performed with two different evaporators, both having the same air-side area but one having only half the refrigerant-side area. The results show that COP improvement of up to 16% with the ejector recirculation cycle and 9% with the standard ejector cycle is obtained, but the COP of each cycle is very dependent on evaporator design. The cycle with the highest COP depends on given evaporator design and ambient temperature.

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