Improving the efficiency of a jet pump using an elliptical nozzle

This note presents a unique means of increasing the efficiency of a jet pump. Much research has been devoted to the study of elliptical nozzles on jets and their ability to increase the amount of fluid entrainment over round jets with equal perimeters. 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 of these elliptical nozzles. In this study, the efficiency of a jet pump is measured using a jet with a round cross section and a jet with an elliptical cross section that has a 3:1 aspect ratio. At high flowrates, the jet pump using the elliptical jet is shown to have an efficiency that is approximately a factor of 6 greater than the pump using the round jet.