Jets Injected Normally into Compressible Crossflow

Abstract

An overview of in-flight experiments and modeling relevant to the compressible transverse jet, in subsonic and transonic crossflow, is described here. Modeling efforts employed a low order, locally two-dimensional representation of the transverse jet, relying on the presence and dynamics of the counter-rotating vortex pair that is observed to dominate the jet cross-section. The experiments involved injection of iodine-seeded nitrogen into compressible air flow, with trajectory visualization via planar laser-induced fluorescence (PLIF) imaging of the iodine. The experiments were conducted in a flight test fixture situated under the fuselage of an F-104G aircraft, allowing examinations of crossflows in the high subsonic and transonic flow regimes. Both uniform crossflows and the crossflow created by compressible flow over a rearward-facing step were considered in these studies. Further details on these studies may be found in separate papers (Heister & Karagozian (1990a), Heister & Karagozian (1990b), Wang, et al. (1995), Karagozian, et al. (1996)).