Surface Curvature and Roughness Effects on Görtler Vortex Development in Hypersonic Flow

Abstract

This work presents a computational and experimental investigation of surface roughness and concave curvature as control parameters on the development of Görtler vortices in hypersonic flow. Three-dimensional large eddy simulation (LES) was performed for two curvature cases using US3D, an unstructured-grid finite volume computational fluid dynamics (CFD) solver. Experiments were performed on two curvature cases and three roughness element shapes at the University of Texas at San Antonio (UTSA) Mach 7 Ludwieg tube wind tunnel facility. The goal of these studies was to examine how variations in surface roughness and curvature affect the downstream development and transition characteristics of the hypersonic boundary layer formed over concave models. It also serves to extend previous work on the effect of shaped surface roughness on the Görtler instability to the hypersonic regime. The included results demonstrate key features of the relationship between roughness effects, vortex development, and boundary layer transition in hypersonic flows dominated by the Görtler instability that can inform both engineering design and future research.