Parametric analysis of ejector working characteristics in the refrigeration system

A detailed investigation of ejector working characteristics in terms of refrigeration efficiency, ejector entrainment ratio, and irreversibilities in each ejector component (nozzle, mixing chamber and diffuser) is carried out by using R141b, R245fa and R600a as the working fluids. The aim of this paper is to generalize the interactions and relationships of various ejector parameters to get better understanding of the ejector working characteristics in the refrigeration system. External and internal ejector parameters are studied separately. The operating conditions and ejector component efficiencies have significant influence on the ejector behavior, and different refrigerants perform distinctively different in the ejector refrigeration system. However, effects of superheat of the three working fluids are negligible. The irreversibility related to the shock process dominates in the diffuser and plays an important role in the ejector performance. Further attention is paid on an analysis of quantifying the ejector component efficiencies based on published test data. Correlations are established to estimate the ejector efficiency and to show how ejector parameters interact. (C) 2014 Elsevier Ltd. All rights reserved.