Investigation on Characteristics of Ejector Refrigeration Using CFD

Ejector refrigeration system is usually designed to utilize the low-grade energy for driving the cycle. It also has a low maintenance cost, because it operates without compressor. Mainly, the ejector performance directly affects the refrigerating performance. Therefore, an investigation on characteristics and an efficient design of the ejector are important to improve the ejector refrigeration system. In this study, Computational Fluid Dynamics (CFD) code (FLUENT) is employed to predict the flow phenomena and performance of CPM and CMA steam ejector. The ejector refrigeration system, using water as the working fluid, is operated at 120oC-140oC of boiler and 5oC-15oC of evaporator temperature. CFD can predict the ejector performance, very well and reveals the effect of operating conditions on an effective area which is directly related to its performance. Besides, it is found that the flow pattern doses not depend much on suction zone because the results of axis symmetric and 3D simulation are similar. This investigation aids to understand the ejector characteristics and provide the information for designing ejector to suited the optimum condition.