Figure 1. X2 with both channels firing simultaneously.
Figure 2. X2 installed on the inverted-pendulum thrust stand.
Nesting is a relatively unexplored concept of clustering discharge channels.
Prior to the PEPL's X2, the performance of a nested-channel Hall thruster had never been published, and the potential advantages of this concept had not been confirmed.
The X2 was developed by PEPL and AFRL to determine the capabilities and characteristics of the nested-channel configuration, and the X3 nested-channel Hall thruster has demonstrated powers to 61 kW and is designed to achieve power levels of 200 kW.
Nesting discharge channels can decrease the footprint area and reduce thruster mass of a high-power Hall thruster.
Additionally, the nested-channel configuration features the ability to change the exit area through the selective activation of available channels.
Use of different combinations of discharge channels offers an additional method of throttling and permits multiple design points for the overall thruster.
Performance measurements of the nested-channel Hall thrusters are determined using an inverted-pendulum thrust stand of NASA Glenn design.
Plume measurements are taken using PEPL diagnostics, including the Langmuir probe, Faraday probe, retarding potential analyzer, and ExB probe.
Selected Relevant Publications
Florenz, R., Hall, S., Gallimore, A., Kamhawi, H., Griffiths, C., Brown, D., Hofer, R., Polk, J., "First Firing of a 100-kW Nested-channel Hall Thruster," 33rd International Electric Propulsion Conference, Washington, D.C., October 6-10, 2013.
R. Liang and A. Gallimore, "A 6-kW Laboratory Hall Thruster with Two Concentric Discharge Channels,"
Poster Presentation, 31st International Electric Propulsion Conference, Ann Arbor, MI, USA, September 20-24, 2009.
R. Liang and A. Gallimore, "Performance of a Laboratory Hall Thruster with Two Concentric Discharge Channels,"
57th Joint Army Navy NASA Air Force (JANNAF) Propulsion Meeting, Colorado Springs, CO, May 3-7, 2010.