Plasma-material boundary conditions for discontinuous Galerkin continuum-kinetic simulations, with a focus on secondary electron emission

Abstract

Continuum kinetic simulations of plasmas, where particle distribution functions are directly discretized in phase-space, permit fully kinetic simulations without the statistical noise of particle-in-cell methods. Recent advances in numerical algorithms have made continuum kinetic simulations computationally competitive. This work presents a continuum kinetic description of high-fidelity wall boundary conditions that utilize the readily available particle distribution function without coupling to additional physical models. The boundary condition is realized through a reflection function that can capture a wide range of cases from simple specular reflection to more involved first principles models. While the framework is usable for various numerical methods and boundary conditions, this work focuses on the discontinuous Galerkin implementation of electron emission using a first-principles quantum-mechanical model. Presented results demonstrate effects of electron emission from a dielectric material on formation of a classical plasma sheath.