Abstract: The compressibility effect in the hypersonic shock wave/boundary layer interaction is much stronger than that in the supersonic interaction, and after the reattachment, the high local pressure and thermal load will form, thereby significantly influencing the flight safety of vehicles. The three-dimensionality of the shock wave/boundary layer interaction further complicates the flow structures, making them more difficult to predict. In this study, a direct numerical simulation on the hypersonic shock wave/boundary layer interaction is performed. The effects of G rtler vortices on the separation bubble, the wall pressure and the heat flux are investigated both qualitatively and quantitatively. The investigation results indicate that the separation bubble exhibits obvious three-dimensionality and the size of the bubble at the spanwise separation location is significantly smaller than that at the spanwise reattachment location. The bubbles at the two locations change synchronously. The pressure and the heat flux exhibit inhomogeneous distribution in the spanwise direction. The mean pressure and the heat flux at the spanwise reattachment location are 13% and 16.2% higher than those at the spanwise separation locations, respectively. The ratios for the fluctuations of pressure and heat flux are 28% and 20% higher, respectively. The proper orthogonal decomposition analyses indicate that the energy concentrates on the shear layer above the bubble and the low-order modes at the spanwise reattachment occupy more energy than those at the separation location.

Key words: shock wave/boundary layer interaction, direct numerical simulation, hypersonic, Görtler vortices, proper orthogonal decomposition