<title>Unsteady flows inside structures: high-speed visualization as a tool for numerical modeling and code validation</title>

Abstract

High-speed shadow-and schlieren photography have played a decisive role in the past decades of shock wave physics. Since many of the fundamental processes seem to be sufficiently understood and numerical techniques for hydro-dynamic simulations have advanced to versatile tool in this area, the interest has shifted towards the complexities that arise in realistic scenarios where shocks and blast waves are of importance.This study presents the results of a shock tube experiment that models the flow phenomena in a chamber subjected to a shock that impinges on the entrance to the room. Despite the simple geometry the resulting flow is comparatively complex and reflects many of the effects encountered in more realistic setups. It is dominated by multifold shock reflections passing through the jet-like inflow that soon becomes turbulent. Classical visualization techniques and pressure measurementssupplemented by numerical simulations -were used to analyze the flow field. This combination of qualitative visualization, quantitative point measurements and numerically obtained results proved to be a helpful approach to rate the influence of turbulent velocity fields onto shock wave propagation.