APS Logo

Acceleration Phase Rayleigh-Taylor Instability in Planned Double Cylinder Experiments for OMEGA and NIF

ORAL

Abstract

Cylindrical implosions are used to study hydrodynamic instability growth for ICF applications, as the cylindrical geometry allows for easier diagnostic access while retaining convergence effects. We are working on a double cylinder experimental platform as an analogue to the double shell ICF capsule in order to study hydrodynamic instability growth on the inner shell. We present designs for double cylinder targets that will be fielded at the OMEGA laser facility and the National Ignition Facility. Our design work is done with xRAGE [Comput. Sci. & Disc. 1, 015005] radiation-hydrodynamics simulations, considering the axial uniformity of the implosion in multiple laser drive configurations, the effects of radiation diffusion, and the feasibility of measuring the instability growth with pre-seeded single mode perturbations. We evaluate the designs for visibility of instability growth, finding for the OMEGA design that spikes on the tamper/inner cylinder interface grow to a maximum of 50-70μm in length. Axial bowing extent is at most 4μm radially, and with a diagnostic resolution of ~10μm, we expect the spikes to be visible. Preheat due to radiation diffusion reduces the length of the spikes by up to 30μm; however, synthetic radiographs show that the spikes should still be visible.

Presenters

  • Rebecca Roycroft

    Los Alamos National Laboratory

Authors

  • Rebecca Roycroft

    Los Alamos National Laboratory

  • Joshua P Sauppe

    Los Alamos National Laboratory

  • Paul A Bradley

    Los Alamos Natl Lab, LANL

  • Sasi Palaniyappan

    Los Alamos Natl Lab, Los Alamos National Laboratory, Los Alamos National Lab