Investigation of turbulent high-speed flow over the double wedge at varying aft-wedge deflections

Abstract

This study examines the shock–shock (SSI) and shock-wave boundary layer (SBLI) interaction mechanisms over the two-dimensional double wedge exposed to hypersonic Mach 5 flow. Several Unsteady Reynolds-averaged Navier Stokes (URANS) based turbulence models are used systematically to determine the most suitable model. Grid sensitivity analysis indicates that while the laminar model is sensitive to grid size, turbulent models exhibit grid independence, suggesting the laminar model’s unsuitability under these conditions. We further support this hypothesis by a qualitative and quantitative comparison of the numerical schlieren images and mean wall heat flux profiles, respectively, with the experimental results. The average heat flux based on the fully laminar assumption provides accurate predictions in the well-attached flow region, but it fails horribly after the SBLI interaction. The models using the standard $k-\omega$ SST (shear stress transport) turbulence model and the four-equation Lantry–Menter correlation-based model consistently overpredict the wall heat transfer rate throughout the double-wedge surface. The newly employed Krause correlations significantly improve the match with the qualitative and quantitative experimental observations. This article further uses this novel turbulence model to explore the impact of the aft-wedge angle variation ($45^0\le {\theta }_2\le 60^0$) on the shock–shock interaction mechanisms and the associated wall properties. Results indicate a weak Edney type-V interaction at the lowest angle, transitioning to Edney type-V with Mach reflection for ${\theta }_2\ge 50^0$. Hence, the critical transition aft-wedge angle concerning the change in the shock interference pattern is between ${\theta }_2=45^0$ and ${\theta }_2=50^0$.