Investigation of Shock-Boundary Layer Interaction in a Ramp Flow with MVG Under Different Turbulent Inflows

MVG (micro vortex generator) is a potentially new device which can alleviate or overcome the adverse effects of SBLI (Shockboundary layer interaction) and improve the “health” of the boundary layer. In this paper, the SBLI in a ramp flow with MVG under different inflow conditions is investigated by LES (large eddy simulation). Three turbulent inflows with different boundary layer thickness are generated based on turbulent profiles obtained from DNS (Direct numerical simulation) of transition. The numerical results show that the interaction between ring-like vortices generated by MVG and the ramp shock is influenced by these different inflow conditions. With lower boundary layer thickness, the ring-like vortices are less distorted and thus more stronger when they travel to the ramp corner. The more regular and stronger ring-like vortices have more capability to eliminate or distort the strong ramp shock wave. Moreover, it confirms that ring-like vortices generated by MVG, and not the lower turbulent boundary layer, is dominant in flow separation reduction.

Keywords: LES, MVG, Flow control, Turbulence, SBLI

Abbreviations: MVG: Micro Vortex Generator; SBLI: Shock-Boundary Layer Interaction; DNS: Direct Numerical Simulation; M: Mach Number; Re: Reynolds Number Based on Momentum Thickness; H: Micro Ramp Height; δ: Incompressible Boundary-Layer Nominal Thickness; X, Y, Z: Spanwise, Normal and Streamwise Coordinate Axes; u, v, w: Spanwise, Normal and Streamwise Velocity