Experimental study of the effect of some geometric variables and number of nozzles on the performance of a subsonic air—air ejector

Abstract

An ejector is a pumping device that uses a high-speed primary fluid jet to entrain a secondary stream. The pumping action is due to the exchange of momentum between the primary and secondary streams. The air ejectors are widely used in mixing systems and many engineering applications. The purpose of the present work is to study experimentally the effects of using different numbers of nozzles with various geometric variables on the performance of the air ejector. The test rig, which is designed particularly for this study, is constructed so that the overall performance of the air ejector can be measured under various operating conditions. To the best knowledge of the authors, there is no published work concerning the study of all the geometric variables with different numbers of nozzles, showing their effect on the ejector performance. The experimental investigations consist of the performance measurements for 52 ejectors. They are classified into three main groups The following conclusions were drawn