Characteristics of Non-Steady Pressure Exchange Ejectors

The work to be presented herein is a Computational Fluid Dynamics investigation of the complex fluid mechanisms that occur inside a non-steady, three-dimensional, supersonic pressure exchange ejector, specifically with regard to the pressure exchange mechanisms and the induction processes between a driving “primary” fluid and a driven “secondary” fluid and how this is related to the pressure exchange zone. This paper is based upon utilizing a non-steady flow field resulting in the work of pressure forces acting at a fluid interface between primary and secondary flows. These interfaces are produced through the aerodynamic design of a flow field, non-steady in the laboratory frame of reference, consisting of rotating oblique shock waves and expansion fans. Minimizing the possible losses from the oblique shocks and boundary layers offer the potential of achieving adiabatic efficiencies approaching those of turbo-machines. The results will show the length of pressure exchange zone. Results will show some characteristics of flow induction mechanism, especially when a pressure recovery is needed.