Kinetic scrape off layer simulations with semi-Lagrangian discontinuous Galerkin schemes

TL;DR

This paper introduces a semi-Lagrangian discontinuous Galerkin method for simulating plasma scrape-off layers, featuring adaptive velocity space, specialized mesh, and efficient limiters optimized for GPU computation.

Contribution

It presents a novel limiter for semi-Lagrangian DG schemes that is computationally efficient on GPUs and suitable for plasma edge simulations.

Findings

The proposed limiter performs favorably compared to existing methods.

Numerical benchmarks demonstrate the method's accuracy and efficiency.

Adaptive velocity space improves simulation of fast particles.

Abstract

In this paper we propose a semi-Lagrangian discontinuous Galerkin solver for the simulation of the scrape off layer for an electron-ion plasma. We use a time adaptive velocity space to deal with fast particles leaving the computational domain, a block structured mesh to resolve the sharp gradient in the plasma sheath, and limiters to avoid oscillations in the density function. In particular, we propose a limiter that can be computed directly from the information used in the semi-Lagrangian discontinuous Galerkin advection step. This limiter is particularly efficient on graphic processing units (GPUs) and compares favorable with limiters from the literature. We provide numerical results for a set of benchmark problems and compare different limiting strategies.