Tracking the transition to turbulence in simulations of hydrodynamic instabilities of National Ignition Facility shock-tube experiments

The development of an experimental campaign at the National Ignition Facility (NIF) is underway to study the hydrodynamic growth of Rayleigh-Taylor (RT) and Richtmyer–Meshkov (RM) instabilities in nonlinear and turbulent regimes. The campaign is also developing the diagnostic capabilities to improve spatial resolution, which will enable visualization of fine flow details. With a sufficiently optimized platform and by applying multiple shocks to the interface, the transition to turbulence may be observed in the short duration of a high-energy-density experiment. We compare analyses of synthetic data from the multi-physics code ARES with experimental radiograph images from NIF to assess the prospect of utilizing Fourier modes to track progress into the turbulent regime. The results will be used to guide the optimization of the diagnostics and to define metrics that can be applied to higher-resolution data to validate our simulations.



Prepared by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-851379