A REVIEW OF EJECTOR TECHNOLOGY FOR REFRIGERATION APPLICATIONS

Abstract

This paper provides a comprehensive review of ejector technology for refrigeration applications, combining an understanding of basic fluid flow fundamentals within the ejector with application in cycle-level development. An ejector is a passive device that requires no external mechanical input or moving parts. A high-velocity motive stream produces a low-pressure region into which a suction flow is entrained, resulting in a pressure rise of the suction flow and mixing between the two streams to provide a pumping effect. The first part of this review addresses the progression from experiment-based analytical models to computational modeling of the ejector itself from the early 1950s to 2009. Included is an assessment of the most recent work in CFD modeling, and an exploration into what is needed to develop these models further. Suggestions for future research include better modeling of shock phenomena and the effects of two-phase flow in ejectors. The second part of this review focuses on ejector applications in refrigeration cycles with special emphasis on the vapor-jet refrigeration cycle. Important connections are made between ejector component and system level studies, an understanding of which would enable improvement of system level performance to the extent where they could be used in some niche applications instead of conventional refrigeration systems.