Self-Entrainment Characteristics and Performance of a Compact Air Ejector Available to Purchase

A one dimensional method of analysis and experimentally determined entrainment and compression ratios are presented with considerations made for constant pressure and constant area mixing. A set of three nozzles, one converging and two converging diverging, were used to study the isentropic characteristics of the ejector performance. Ejector efficiencies are calculated using the turbomachinery analogue of compressors where adiabatic and complete mixing of primary and secondary fluids is assumed before discharge. Efficiencies are characterized against non-dimensional parameters chosen in context. A generalized algorithm and corresponding MATLAB™ based computer program was developed for performance analysis. While exploring the possibility of a refrigeration system for automotive applications where the size of the ejector could play an important role, a compact experimental ejector was designed and tested.