Bump-Induced Oblique Detonation Waves: Shock/Boundary-Layer Effects

The integration of bump-induced oblique detonation technology into the combustor walls of oblique detonation engines presents a promising method for initiating combustion. However, the impacts of shock-wave/boundary-layer interactions (SWBLIs) on this process have not been thoroughly investigated. This study explores how SWBLIs affect oblique detonation waves (ODWs) generated by a bump on a flat plate. The investigation employs numerical solutions to the two-dimensional, multispecies compressible Reynolds-averaged Navier–Stokes equations, utilizing a two-equation [Formula: see text] shear stress transport turbulence model and a detailed hydrogen combustion kinetics model. Findings indicate that in the absence of a boundary layer, ODWs induced by semicylindrical bumps display two modes: sustained and decoupled detonations, delineated by a critical initiation radius. When an upstream boundary layer is considered, SWBLIs lead to the formation of a separation shock wave, a separation bubble, a shear layer, and a reattachment shock wave. These interactions are determined by the coupling status between the combustion front and the shock front, resulting in five initiation modes as the bump radius increases or the boundary-layer thickness decreases: uncoupled, delayed, prompt, advanced, and detached detonations. Additionally, the presence of a boundary layer raises the critical radius required for ODW initiation, with this radius increasing further as the boundary-layer thickness grows.