Shock-wave/turbulent boundary-layer interactions in nonequilibrium flows

Shock-wave/turbulent boundary-layer interactions in the presence of thermal and chemical nonequilibrium phenomena are analyzed. The approach relies on a linear eddy viscosity two-equation turbulence modeling that accounts for the coupling of turbulence with chemistry and vibration, and it employs a total variation diminishing finite volume numerical methodology. The capability of the model has first been assessed for a cylinder flare configuration, and results have been compared with experiments. The model has then been applied to assess the aerodynamic performance of control surfaces of a reusable launch vehicle. In particular, the effects of wall temperature and flap deflection on the separation, aerothermal loads, and flap efficiency have been studied. The analysis shows that turbulence becomes important for flap deflection angles greater than a critical value [O (15 deg)], thus avoiding the crisis of the flap efficiency that is observed under laminar conditions and extending the operating capabilities of the control surface. The study also shows that the wall temperature affects significantly the efficiency and the operating envelope of the flap primarily under turbulent conditions.