GALCIT Colloquium

The interaction between shock waves and turbulent boundary layers is relevant, among other applications, to the design and operation of hypersonic propulsion systems, such as scramjet engines. Duct-like geometries, commonly found in scramjets, translate into confinement effects being imposed onto the interactions developed along the duct walls. These confinement effects are not present in the canonical configuration, most often studied. In this talk I will present numerical simulations aimed at investigating the three-dimensional effects resulting from the flow confinement imposed on shock/turbulent boundary layer interactions by the presence of side walls in a duct with a low-aspect-ratio cross section.  This work constitutes the numerical part of a combined experimental and simulation effort. Three different strengths of the incident oblique shock wave, generated by a small compression wedge spanning the top wall of the duct, will be considered. For the strongest interaction, mean flow separation exists.  Based on the results and the comparison with experimental data, I will discuss the predictive capability of large-eddy simulations employing an equilibrium wall-model for this flow type at the moderately high Reynolds number of the experimental configuration. To assess the effect that upstream geometric perturbations can have on the response of the base shock/turbulent-boundary-layer interaction, additional simulations based on Reynolds-Averaged Navier-Stokes equations will be presented and compared with experimental data. The effect that other aleatory and epistemic uncertainties have on the interaction will also be considered.