Multi-species ion transport in ICF relevant conditions

POSTER

Abstract

Classical transport theory based on Chapman-Enskog methods provides self consistent approximations for kinetic fluxes of mass, heat and momentum for each ion species in a multi-ion plasma characterized with a small Knudsen number. A numerical method for solving the classic forms of multi-ion transport, self-consistently including heat and species mass fluxes relative to the center of mass, is given in [Kagan-Baalrud, arXiv '16] and similar transport coefficients result from recent derivations [Simakov-Molvig, PoP, '16]. We have implemented a combination of these methods in a standalone test code and in xRage, an adaptive-mesh radiation hydrodynamics code, at LANL. Transport mixing is examined between a DT fuel and a CH capsule shell in ICF conditions. The four ion species develop individual self-similar density profiles under the assumption of P-T equilibrium in 1D and show interesting early time transient pressure and center of mass velocity behavior when P-T equilibrium is not enforced. Some 2D results are explored to better understand the transport mix in combination with convective flow driven by macroscopic fluid instabilities at the fuel-capsule interface. Early transient and some 2D behaviors from the fluid transport are compared to kinetic code results.

Authors

  • Erik Vold

    Los Alamos National Laboratory

  • Grigory Kagan

    Los Alamos National Laboratory, LANL

  • Andrei Simakov

    Los Alamos National Laboratory

  • Kim Molvig

    Los Alamos Natl Lab, Los Alamos National Laboratory

  • Lin Yin

    Los Alamos National Laboratory

  • B.J. Albright

    Los Alamos Natl Lab, Los Alamos National Laboratory