Modeling Arcs

TL;DR

This paper presents a comprehensive model of vacuum arcs, integrating plasma physics, surface damage, and electrostatics to better understand arc initiation, development, and limits across various applications.

Contribution

It introduces a multi-scale, self-consistent modeling framework combining PIC, molecular dynamics, and finite element methods to analyze vacuum arc phenomena.

Findings

Unified explanation of arc triggering and plasma evolution

Identification of common mechanisms across different arcing scenarios

Enhanced understanding of surface damage and gradient limits

Abstract

Although vacuum arcs were first identified over 110 years ago, they are not yet well understood. We have since developed a model of breakdown and gradient limits that tries to explain, in a self-consistent way: arc triggering, plasma initiation, plasma evolution, surface damage and gra- dient limits. We use simple PIC codes for modeling plasmas, molecular dynamics for modeling surface breakdown, and surface damage, and mesoscale surface thermodynamics and finite element electrostatic codes for to evaluate surface properties. Since any given experiment seems to have more variables than data points, we have tried to consider a wide variety of arcing (rf structures, e beam welding, laser ablation, etc.) to help constrain the problem, and concentrate on common mechanisms. While the mechanisms can be comparatively simple, modeling can be challenging.