Modeling the Effect of Shock Unsteadiness in Shock/ Turbulent Boundary-Layer Interactions

Reynolds-averaged Navier–Stokes (RANS) methods often cannot predict shock/turbulence interaction correctly. This may be because RANS models do not account for the unsteady motion of the shock wave that is inherent in these interactions. Previous work proposed a shock-unsteadiness correction that significantly improves prediction of turbulent kinetic energy amplification across a normal shock in homogeneous isotropic turbulence. We generalize the modification to shock-wave/turbulent boundary-layer interactions and implement it in the k– , k–ω, and Spalart–Allmaras models. In compression-corner flows, the correction decreases the turbulent kinetic energy amplification across the shock compared to the standard k– and k–ω models. This results in improved prediction of the separation shock location, delayed reattachment, and slower recovery of the boundary layer on the ramp. For the Spalart–Allmaras model, the modification amplifies eddy viscosity across the shock, moving the separation location closer to the experiment.