Thin layer Richtmyer-Meshkov experiments classically and at the NIF*

The Richtmyer-Meshkov instability arises when a shock crosses the boundary between materials of different densities and can lead to complete fragmentation of a thin dense layer. Experiments at NIF have tested the feedthrough of different small scale initial conditions together with a single mode perturbation, but with different broadband profiles, in both single shock and shock-re-shock scenarios. The results find that the mixing depends strongly on the broadband component of the initial condition. A scaling study compares these experiments with similar layered Richtmyer-Meshkov experiments performed with heavy gas curtains in conventional shock tubes. Analysis in terms of a Reynolds-Averaged mix model highlights similarities in the dynamics between the two experiments, despite their disparate scales (from centimeter-microsecond for the gas curtain shock tube to micrometer-nanosecond scale for the laser driven experiments).