Analytical Extraction of Plasma Properties Using a Hall Thruster Efficiency Architecture (Preprint)
Abstract
An investigation of the conversion from anode electrical energy to jet kinetic energy in a laboratory model Hall thruster test-bed yielded an experimentally determined thrust efficiency based on the product of propellant, voltage, and current utilization. This method accounts for the effects of the ion velocity distribution function (VDF), electron recycle fraction, plume divergence, and the fractional loss of acceleration voltage within the discharge chamber. The architecture of the efficiency analysis is such that energy efficiency becomes naturally expressed as a product of voltage and current utilization efficiencies, and is rigorously separated from propellant utilization efficiency. A systematic investigation of the performance and far-field plume measurements provided insight into the loss mechanisms and plasma properties from 100 to 400 V discharge. Experimental parameter groups are calculated based on the measured thrust and telemetry data. When interpreted with measured ion beam current and most probable ion voltage, the efficiency analysis enables several plasma parameters to be deciphered, including: average ion charge, ionization mass fraction, and momentum beam divergence half-angle. The following study creates an analytical map for extracting plasma parameters based on performance and plume measurements.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 22, 2007
- Accession Number
- ADA473504
Entities
People
- Alec D. Gallimore
- Carl William Larson
- Daniel L. Brown
- James M. Hass
Organizations
- Air Force Research Laboratory