Wall Vortices Induced by Re-Shock in RMI Shock Tube Experiments*

The Richtmyer-Meshkov Instability (RMI) is frequently studied in shock tubes, where the walls and relatively narrow cross sections introduce boundary layers that influence the development of the RMI. Traditional RMI analysis assumes statistically two-dimensional flow and sufficient distance from wall effects; however, previous work has shown that vortices form in the boundary layer upon re-shock due to baroclinic vorticity deposition.  Experiments investigating this phenomenon were conducted in the Wisconsin Shock Tube Laboratory at UW-Madison using planar laser-induced florescence and particle image velocimetry for the case of a Mach 1.8 shock wave and an interface with an Atwood number of 0.75. Concurrently, a preliminary simulation using the LLNL hydrodynamics code Miranda was performed to further quantify the impact of the wall vortex on the interface evolution.