Simulation and Analysis of Mixing Layer Evolution in Multi-Mode, Laser-Driven Rayleigh-Taylor Experiments

Recent experiments at the Omega laser facility have produced data of sufficient quality to investigate structural details of single- and multi-mode Rayleigh-Taylor instability growth. The FLASH hydrodynamics code has been used to model these experiments in two and three dimensions. We present a comparison between the experimental data and raytraced images of the three-dimensional simulations, and we also explore the effects of choosing different adiabatic indexes for our ideal-gas realizations of the two fluids. Finally, we contrast the simulated evolution of single- and double-mode perturbations in terms of their mixing layer growth and mass distributions. In accordance with theoretical expectations, we find that short-wavelength modes show the fastest initial growth, and that the structure of the mixing layer is eventually dominated by the longer modes.