Direct Numerical Simulations are performed in order to investigate the physics of a hypersonic flow on different configurations of a compression corner, a typical ramp geometry characterising control surfaces of re-entry vehicles. The numerical experiments, carried out considering both an adiabatic and a cold-wall condition, include the presence of a sinusoidal roughness patch placed at various locations upstream of the ramp. The roughness elements placed upstream of the smooth separation point stretch the recirculation bubble towards the roughness position and affect the heat-flux peaks at the wall. Under conditions of a low enough wall temperature, instead, the placement of the roughness patch just in front of the corner can significantly limit the growth of the recirculation bubble.     «

Direct Numerical Simulations are performed in order to investigate the physics of a hypersonic flow on different configurations of a compression corner, a typical ramp geometry characterising control surfaces of re-entry vehicles. The numerical experiments, carried out considering both an adiabatic and a cold-wall condition, include the presence of a sinusoidal roughness patch placed at various locations upstream of the ramp. The roughness elements placed upstream of the smooth separation point...     »