Global Linear Stability and Sensitivity of Hypersonic Shock-Boundary Layer Interactions

Abstract

Understanding physical mechanisms that cause transition of laminar boundary layers to turbulent state in hypersonic flows is important for vehicle design and analysis. Mechanisms of linear perturbation growth in high speed boundary layers subjected to abrupt inviscid pressure jumps have been relatively less studied. Inviscid pressure jumps are associated with geometry effects and impinging shocks. They cause the boundary layer to separate, forming a separation-reattachment shock system. In the present study, we investigate small perturbation growth in a nominally two-dimensional interaction on a slender double wedge. We report and discuss intrinsic instabilities as well as amplification of external perturbations in the setup, both of which result in streamwise heat flux streaks near and post-reattachment.