AIRFOIL PRESSURE MEASUREMENTS DURING OBLIQUE SHOCK-WAVE VORTEX INTERACTION IN A MACH-3 STREAM

An experimental investigation of the interaction between streamwise di screte vortices and oblique shocks formed over a two-dimensional wedge surface was conducted in a Mach 3 blowdown wind tunnel. An instrument ed two-dimensional wedge section was placed downstream of a semispan w ing so that the trailing tip vortex would arbitrarily interact with th e shock wave formed over the wedge surface. The experiments were desig ned to simulate interaction of streamwise vortices from upstream bodie s with shock waves formed over aft surfaces as might be encountered in supersonic flight of aircraft and missiles. The influence of vortex s trength and vortex-airfoil vertical separation distance on the interac tion was examined. The flowfield generated was found to be highly unst eady, and a substantial change in the pressure distribution on the dow nstream airfoil was observed. The interaction or a strong vortex with the oblique shock wave over the downstream wedge section resulted in f ormation of an unsteady detached shock wave upstream of the wedge lead ing edge. Furthermore, when the vortex approached the wedge leading ed ge, formation of a detached shock wave occurred further upstream of th e section leading edge.