Investigating Shock-Boundary layer Interaction via Direct Numerical Simulations

Shock-boundary layer interaction (SBLI) in the isolator of scramjet engines is a critical phenomenon that significantly affects the performance and stability of hypersonic air-breathing propulsion systems. This study investigates this complex interaction through direct numerical simulations (DNS) coupled with adaptive mesh refinement (AMR) and the Embedded Boundary (EB) method, enabling the resolution of shocks at the finest scales while maintaining computational efficiency. Initially, the effect of inflow turbulence on the near-wall region is explored by maintaining a sufficiently low back pressure to avoid the formation of shock-trains. Subsequently, the back pressure is increased which leads to the formation of shock-trains, and the effect of inflow turbulent conditions on shock-train dynamics is investigated. The results show a prominent effect of the inflow turbulence on the shock-train dynamics and in turn the shock-trains lead to flow separation near the wall and enhance the near-wall turbulence which have direct implications on the air-fuel mixing downstream of the isolator.