Direct Numerical Simulations of the Mach 6 Flow Past a Control Fin*

Control fins that enable maneuvers of high-speed flight vehicles experience pressure and thermal loads that cause them to deform. To understand these loads, we use direct numerical simulation (DNS) to simulate the Mach 6 flow past a representative fin geometry at zero and four degrees angles of attack. The fins are swept with a constant-thickness diamond airfoil cross section and have blunted leading and trailing edges. The DNS boundary conditions are informed by corresponding Reynolds-averaged Navier-Stokes (RANS) simulations of the fins mounted to a blunted conical centerbody. We focus our discussion on the boundary layer transition that occurs on the fin surface and on its sensitivity to freestream disturbances that pass through the shock.