Measurements of mixing induced at a gas interface by the Richtmyer-Meshkov instability

Abstract

Experiments to study the mixing between two gases induced by the Richtmyer-Meshkov instability are performed in a vertical shock tube of large, square internal cross section. The test gas is contained in an axisymmetric soap bubble which is at rest on an injector and is seeded with smoke to perform planar Mie scattering. Concurrently to the laboratory experiments, a computational investigation is carried out using the Raptor code- a finite volume code that solves the compressible Navier-Stokes equations using a Riemann solver with Phil Colella's Piecewise Linear Method for data reconstruction at cell interfaces. Differences between the computational and the laboratory experiments include: perfectly spherical vs. near-spherical, axisymmetric shape; diffuse interface with no soap film vs. soap interface with no diffusion; absence vs. presence of an injector to hold the bubble in place. Examples of experimental and computational images of shock-accelerated bubbles are shown below.