The stabilizing effect of grooves on Görtler instability-induced boundary layer transition in hypersonic flow

Görtler vortex-induced hypersonic boundary layer transition controlled by grooves is investigated using direct numerical simulations and spatial bi-global stability analysis. In the simulations, vortices are excited wall steady blowing suction with spanwise wavelengths of 3 mm. It found that when covered grooves, streaks keep more regular even at end model. addition, skin friction coefficient reduced efficiently. Furthermore, wall-normal velocity shear both reduced, suppressing growths secondary instabilities. conclusion, can delay modifying structure instability, which would shed light on control.