Numerical investigation of centrifugal effects in high-speed turbulent boundary layers*

Supersonic and hypersonic turbulent boundary layer transition has recently seen a resurgence of interest, motivated by the need to improve the design and optimization of supersonic and hypersonic vehicles, increase the efficiency of scramjet engines, or to quieten high-speed wind tunnels. The surface of realistic vehicles features regions of convex or concave curvature, which not only changes the streamwise pressure gradient but also alter the development of turbulent flow structures. Centrifugal effects come into play when the boundary layer flow evolves over a concave wall, accommodating Gortler-like vortices that feature mushroom shapes in crossflow contours of streamwise velocity. In this work, we study these centrifugal effects in a Mach 7 turbulent boundary layer flow by large eddy simulations, by varying the curvature of the wall and the Reynolds number.