Crossplane Velocimetry of a Transverse Supersonic Jet in a Transonic Crossflow

Abstract

Stereoscopic particle image velocimetry has been employed to study the interaction created by a supersonic axisymmetric jet exhausting transversely from a flat plate into a transonic crossflow. Data have been acquired in the crossplane of the interaction at a single station in the far field, from which the velocity field identifies the induced counter-rotating vortex pair as well as the remnant of the horseshoe vortex that wraps around the jet plume as it first exhausts from the nozzle. Data taken for four different values ofthejet-to-freestream dynamic pressure ratio reveal the resulting change in the vortex characteristics, where the vortex strength, size, and position are established from the derived vorticity field. Sufficient data were acquired at one condition to determine all six unique components of the turbulent stress tensor, providing the mean spatial character of the anisotropic turbulence. A measureable degree of asymmetry is observed in the size and lateral position of the counter-rotating vortex pair. Self-similarity is established laterally when dimensions are scaled by either the vortex diameter or the horizontal vortex spacing; in the wall-normal direction, scaling is found with the vortex diameter once the vortex penetration is accounted.