Performance of Control Jets on Curved Bodies in Supersonic Cross Flows

Abstract

A control jet injected into a supersonic cross flow causes a significant disruption of the external flow in the vicinity of injection, altering the pressure distribution on the parent body and the effectiveness of the injected jet in producing control forces and moments. In this study, numerical simulations were carried out in order to estimate the dependence of this effectiveness on the curvature of the parent body. After validating the simulation methodology using published experimental data, a series of simulations were carried out varying the parent body curvature and external flow conditions while keeping the jet injection parameters fixed. Despite similarity of the basic interaction flow structure for both flat and curved parent bodies, significant differences were observed in the intensity and location of the shocks and vortical structures around the injection. A detailed analysis of the effect of these differences on the pressure distribution and the performance of the control jet was carried out. The interaction on a flat parent body caused a significant amplification of the jet thrust as well as a significant pitch-up moment about the injection. Curved parent bodies were found to contribute negatively to the effectiveness while causing a pitch-down moment about the injection.