Nonlocal transport in magnetised and multi-species plasmas
File(s)
Author(s)
Mitchell, Nicholas
Type
Thesis or dissertation
Abstract
A reduced kinetic method (RKM) for describing nonlocal transport in magnetised plasmas is derived from first principles and considered in a 1D3V geometry. The key feature of this RKM in contrast to other nonlocal closures is using the linearised Fokker-Planck collision operator, which can be shown to match the full, first-principles collision operator for the tail of the particle distributions even with order unity deviation from thermodynamic equilibrium. In a nonlocal transport scenario within a broad hydrodynamic framework, it is the tails of the velocity distributions that are responsible for the relevant transport fluxes, making this description first-principle yet relatively computationally inexpensive. 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. A novel nonlocal effect on current-driven transport, in particular the Ettingshausen heat flow, is found and investigated. Nonlocal transport in ionic mixtures is also described by the RKM, including ordinary, thermo-, and baro-diffusion, and ion conductive, Dufour, and pressure-driven heat flow. Novel nonlocal features associated with multiple species, as opposed to single species, are demonstrated, as well the impact of ion-electron collisions on nonlocal ion transport.
Version
Open Access
Date Issued
2026-04-27
Date Awarded
2026-07-01
Copyright Statement
Attribution-NonCommercial 4.0 International Licence (CC BY-NC)
License URL
Advisor
Kagan, Grigory
Chapman, Dave
Sponsor
First Light Fusion Limited
Publisher Department
Department of Physics
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)