THE ADVANCED PERFORMANCE OF REFRIGERATION CYCLE WITH AN EJECTOR FOR RECIRCULATION - Enhanced Heat Transfer of several Plate-type Evaporators with several Refrigerants

摘要

We have proposed a means that re-circulates vapor of refrigerant in the evaporator by using an ejector to enhance the heat transfer of evaporator in the refrigeration cycle. It makes the evaporating heat transfer coefficient (α{sub}r) higher through increasing the dryness-quality (χ{sub}(in)) of refrigerant at the inlet of evaporator. In this paper, by using several kind of plate-type evaporators and several refrigerants, we investigated experimentally α{sub}r in evaporators and COP of the refrigeration cycle with a proposal means under various ratio of the re-circulation to refrigeration flow rates(G{sub}e/G{sub}n) and evaporating temperatures (0～-10°C). As results of experiments, we confirmed that the α{sub}r was most enhanced, when χ{sub}(in) were increased in about value of 0.5 according to G{sub}e/G{sub}n. At this point, COP increased in the maximum value of 8% compared with conventional cycles on the tested D.C. inverter compressor.