2024/06/25 by C. A. Walsh, Walsh, Chris, M. Sherlock +1 · 1 citation
Engineering · Mathematics · #FOS: Physical sciences #Fluid Dynamics and Turbulent Flows #Gas Dynamics and Kinetic Theory #Plasma Physics (physics.plasm-ph)
paper · pdf · doi:10.48550/arxiv.2406.17942
openalex publication_date 2024/06/25 · openalex created_date 2024/06/28 · openalex updated_date 2026/07/29
Reduced models for approximating the impact of kinetic electron behavior on the transport of thermal energy and magnetic field are investigated. The thermal flux limiter has improved agreement with Vlasov-Fokker-Planck data when a harmonic form is used that adjusts the electron mean free path to account for electron-electron collisions; these results apply to both unmagnetized and magnetized plasmas. Once a magnetic field is incorporated, the mean free path should also be modified using the electron gyroradius. A flux limiter on Nernst advection of magnetic field is also required; a form that limits Nernst by the same fraction as the thermal heat-flow best reproduces kinetic simulations. A flux limiter form for the cross terms (Righi-Leduc and cross-gradient-Nernst) are also suggested. Hohlraum simulations relevant to fusion experiments on the National Ignition Facility are found to be sensitive to all of these details.