Plasma Properties in the Plume of a Hall Thruster Cluster
Abstract
The Hall thruster cluster is an attractive propulsion approach for spacecraft requiring very high-power electric propulsion systems. This article presents plasma density, electron temperature, and plasma potential data collected with a combination of triple Langmuir probes and floating emissive probes in the plume of a low-power, four-engine Hall thruster cluster. Simple analytical formulas are introduced that allow these quantities to be predicted downstream of a cluster based solely on the known plume properties of a single thruster. Ion energy distribution functions measured using both a parallel plate electrostatic analyzer and a retarding potential analyzer are presented. A cluster of Hall thrusters is shown to exhibit dramatically different ion energy profiles compared to a single thruster. In particular, clustering causes a significant increase in the fraction of ions at energies below the primary peak in the distribution, most likely due to an increase in elastic scattering and the effects of the unique plasma potential profiles in the cluster plume.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 04, 2003
- Accession Number
- ADA416762
Entities
People
- Alec D. Gallimore
- Brian Beal
- James Haas
- William Hargus Jr.
Organizations
- Air Force Research Laboratory