Influence of Pressure on Supersonic Retropropulsion Flow Field at Mach 2

Abstract

The effectiveness of Supersonic Retropropulsion is difficult to predict due to the many parameters that can influence the flow field. This thesis uses a combination of control volume and dimensional analyses to propose a minimal set of parameters that are likely to be the primary influencers of this flow interaction. As the most prominent parameter, the influence of stagnation pressure ratio between the jet and freestream flows was experimentally examined using a Ludwieg Tube and schlieren photography. This flow visualization is analyzed quantitatively to identify flow unsteadiness based on measurements of bow shock topography, motion, standoff distance and curvature. Principal Component Analysis (PCA) was also used to identify regions of flow unsteadiness and major flow structures.