Multi-Domain Plasma Expansion Simulations Using a Particle-in-Cell Method
Abstract
The statistical nature of the Particle-In-Cell (PIC) algorithm for plasma modeling requires that a large number of computational particles is used per cell to reduce the numerical noise. This requirement presents a computational obstacle in cases involving rapidly decaying plasmas, such as in simulations of plume expansion from electric propulsion (EP) thrusters. The simulation domain typically contains plasma densities ranging from 10(17) to 10(10) particles/cubic meter. Several approaches for retaining a sufficient per-cell particle count exist, including growth of simulation cells, particle splitting, and particle tracking limited to the back flowing particles, but none of these is without associated problems. In this paper, we present an alternative approach based on a multi-domain modeling. A coarse simulation is used to sample particle flux into a subdomain enclosing the region of interest. A second simulation is then performed on the subdomain, with particles injected at domain boundaries according to the prescribed flux. This approach is used to predict ion current to a simple cylindrical probe located on a satellite using a cluster of four Hall thrusters for primary propulsion. The effect of sheath resolution is investigated and results are compared to an analytical model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 12, 2006
- Accession Number
- ADA454754
Entities
People
- Douglas Vangilder
- Lubos Brieda