A First-Principles Closure for Nonlocal Magnetized Transport

TL;DR

This paper introduces a first-principles reduced kinetic model for nonlocal magnetized plasma transport, capturing various flux behaviors and providing a computationally efficient approach.

Contribution

It develops a novel RKM based on the Fokker-Planck operator that naturally reproduces local transport and models nonlocal effects in magnetized plasmas.

Findings

Observed inhibited peak heat flux and preheat effects.

Demonstrated nonlocal behavior of multiple transport fluxes.

Presented a simplified, efficient version of the RKM.

Abstract

A reduced kinetic method (RKM) for describing nonlocal transport in magnetized plasmas is derived from first principles and considered in a 1D3V geometry. Unlike standard nonlocal closures, this RKM uses the Fokker-Planck collision operator, therefore local transport results are naturally reproduced for small Knudsen number. An inhibited peak heat flux and preheat of the conductive heat flux are observed, which are expected from physical arguments and previous kinetic studies. Nonlocal behavior of other transport fluxes, namely the Righi-Leduc, Peltier, Ettingshausen, Nernst, thermal force, friction, cross friction, viscous stress, and gyroviscous stress terms are also demonstrated. Neglecting the nonlinear component of the Fokker-Planck collision operator is justified a posteriori. An especially computationally efficient and analytically simpler version of the RKM is presented.