Numerical investigations on the wake structures of micro-ramp and micro-vanes

Based on large eddy simulation, combined with the high-order WENO (weighted essentially non-oscillatory schemes) scheme, immersed boundary method and adaptive mesh refinement technique, the supersonic flow past a wall-mounted micro-ramp and two micro-vanes have been simulated. The different wake structures are presented and discussed. Our numerical results showed that wake structures behind the micro-ramp are more complicated, including ring-like vortex train, and streamwise vortex tubes etc. However, the wake structures of the micro-vanes are quite simple; they are mainly the two counter-rotating streamwise vortex tubes. The control of boundary flow of both is achieved through the energy exchange between the main stream and the boundary layer and is presented mainly by the upwash and downwash motion of gases under the entrainment of vortex tubes. (paper)