Improving the efficiency of a jet pump using a swirling primary jet

Abstract

This Note presents a unique means of increasing the efficiency of a jet pump. Much research has been devoted to the study of swirl jets and their ability to increase the amount of fluid entrainment. Since the efficiency of a jet pump is directly related to the ability of the primary jet to entrain fluid, a jet pump is an obvious potential application for a swirl jet. In this study, the entrainment flow and efficiency of a jet pump is measured with and without swirl in the primary jet of a centrally driven jet pump. At moderate swirl, the jet pump is shown to have an approximate 4.5% increase in entrainment flow and a 5% increase in efficiency when compared to the same pump without swirl.