Surface measurements of a supersonic jet in subsonic compressible crossflow

Abstract

Despite many decades of jet-in-crossflow experimentation, a distinct lack of data remains for a supersonic jet exhausting into a subsonic compressible crossflow. The present investigation seeks to address this deficiency by examining the flowfield structure of a Mach 3.73 jet injected transversely from a flat plate into a subsonic compressible freestream. The experimental results described herein include the mean surface pressure field as mapped using static pressure taps and an identificatio n of flow features by employing an oil-based surface flow tracer. The variation of such features as the extent of separated flow regions and the location of vortices is examined as a function primarily of the jet-to-freestream dynamic pressure ratio and the freestream Mach number. The possibility of flow separation within the nozzle itself also is addressed, as is its asymmetry due to the variation of the local backpressure around the perimeter of the nozzle orifice, which results from the jet-in-crossflow interaction.