Ferguson Abstract: Experiments on the Richtmyer-Meshkov Instability in Shock and Reshock

We present experiments on the Richtmyer-Meshkov Instability (RMI) in both the singly shocked and reshock regimes. Air is utilized as the light gas and sulfur hexaflouride (SF6) is utilized as the heavy gas. The gasses are flowed in to the shock tube from above and below the interface location in order to form an initially stable, stratified interface. A pair of oscillating voice coils are used to generate Faraday wave type perturbations on the interface. The flow is visualized using the Particle Image Velocimetry (PIV) technique with propylene glycol/vegetable glycerin particles with a mean diameter of approximately 1.5 micrometer used as a tracer particle. The particles are seeded in to both the heavy and light gasses to provide a PIV visualization of both the heavy and light gas components of the flow.

Two sets of experiments are presented. The first utilizes a traditional single-driver vertical shock tube to study the RMI in the singly shocked regime and a short period in the reshock regime. The second set of experiments utilize a dual driver configuration to study the characteristics of the RMI later in to reshock. Analysis includes measurements of mixed width, rate of decay of kinetic energy, anisotropy of the turbulent mixing zone, and the spectral analysis of scales present in the turbulent flow.