The Vortical Structures in the Rear Separation and Wake Produced by a Supersonic Micro-Ramp

The vortical structures in the rear separation and wake region produced by a micro-ramp that immersed in a supersonic turbulent boundary layer are investigated. The small scale separation was reveled close to the trailing edge and confirms the previous experimental observation. Between the reverse region and surrounding fast moving flow, a three-dimensional shear layer was formed, where vortices are generated. By using vortex line method, those spiral points were understood as the cross sections of the Ω-shaped vortices that follow the shape of the separation. The vortical structure was analogous to that in the wake region, where similar Ω-shaped vortex can be observed and follows the deficit region caused by the micro-ramp. Finally, the revealed flow topology was conceived beneficial to study the wall bounded turbulence which involves similar vortical structure but in a smaller scale, while the vortical pattern in the current micro-ramp wake is larger.