Nonlocal effects on Thermal Transport in MagLIF-Relevant Gaspipes on NIF

ORAL

Abstract

We present simulations of heat flow relevant to gaspipe experiments on NIF to investigate kinetic effects on transport phenomena. These D2 and neopentane (C5H12) filled targets are used to study the laser preheat stage of a MagLIF scheme where an axial magnetic field is applied to the target [1] . Simulations were done with the radiation-MHD code Hydra[2] with a collision-dominated fluid model as well as the Schurtz[3] nonlocal electron conduction model. With nonlocal effects included the center of the gaspipe experienced increased temperatures due to inhibited radial heat flow and a faster laser propagation than without. Motivated for further study, we utilize Hydra to initialize plasma conditions for the Vlasov-Fokker-Planck K2 code[4] . We run until a quasi-steady state is reached and examine the impact of kinetic effects on heat transport. Although axial heat flow was well predicted by fluid models, the radial heat flow was found to be overpredicted by 150% in regions with the largest temperature gradient of D2 filled gaspipes. The Schurtz nonlocal electron conduction model was found to capture kinetic heat flow fairly well. Including self-generated magnetic fields further inhibits radial heat flow causing steeper radial temperature gradients.

Publication: 1 B. Pollock, et. al. Phys. Plasmas 30, 022711 (2023).
2 M. M. Marinak, et. al. Phys. Plasmas 8, 2275-2280 (2001).
3 G. P. Schurtz, et. al. Phys. Plasmas 7, 4238 (2000).
4 M. Sherlock, et. al. Phys. Plasmas 24, 082706 (2017).

Presenters

  • Ryan Yik Wah Lau

    University of Colorado, Boulder

Authors

  • Ryan Yik Wah Lau

    University of Colorado, Boulder

  • David Jerome Strozzi

    Lawrence Livermore Natl Lab

  • Archis S Joglekar

    Ergodic LLC

  • Mark W Sherlock

    Lawrence Livermore Natl Lab

  • William A Farmer

    Lawrence Livermore Natl Lab, Lawrence Livermore National Laboratory

  • Yuan Shi

    University of Colorado Boulder

  • John Robert Cary

    University of Colorado, Boulder, Tech-X Corporation