Project

Stability Analysis of Hall Thrusters


The H9 Hall thruster operating on krypton at 400 V and 15 A. At this condition, the breathing mode is particularly coherent at 20 kHz.

project personnel
Ethan Dale

principal investigator
Benjamin Jorns

affiliated personnel
Kentaro Hara (PDML)

previous personnel
Michael Sekerak

project sponsors
NASA

associated thrusters
H6, H9

Despite active study for decades, the stability of Hall thrusters is still not completely understood from first principles. Specifically, these devices exhibit several instabilities that are not completely characterized theoretically. These stability issues are problematic in two ways: the presence of instabilities may influence performance in-flight, and the lack of understanding of these phenomena makes it difficult to reproduce them with numerical simulation.

Hall thruster stability is studied in several ways. First, it can be examined experimentally in terms of empirical trends in oscillation characteristics with operating parameters. For example, the evolution of oscillation frequency with discharge voltage can be mapped experimentally to understand the stability of a thruster as a function of voltage. Second, it can be examined experimentally in terms of high-level performance metrics. For example, the evolution of power-normalized thrust with oscillation amplitude can be determined to illuminate the effect of instabilities on performance. Finally, it can be examined theoretically and numerically to understand the mechanism governing an instability. For example, a theoretical model can be developed and compared to low-level experimental data to assess the stability criteria for a certain oscillatory mode.

At PEPL, we have approached Hall thruster stability in all three ways. The work of McDonald et al. performed initial characterization of the Hall thruster breathing mode and spoke mode using high-speed imaging. Aside from identifying important trends in frequency and amplitude of these modes, McDonald found evidence that azimuthal spokes might play a role in electron transport in Hall thrusters. Sekerak et al. evaluated the changes in thruster performance with low-frequency oscillation strength and found that the breathing mode typically corresponds to low thrust-to-power. Finally, Dale et al. explored the breathing mode theoretically and numerically, finding that existing theories for it are insufficient. Dale performed additional experimental characterization of this mode and found evidence for the involvement of an upstream ionization process.

Selected Publications


  • Mode Transitions in Hall-Effect Thrusters Induced by Variable Magnetic Field Strength

    M.J. Sekerak, A.D. Gallimore, D.L. Brown, R.R. Hofer, and J.E. Polk

    AIAA Journal of Propulsion and Power, 10.2514/1.B35709, March 2016

  • Plasma Oscillations and Operational Modes in Hall Effect Thrusters

    Sekerak, M.

    University of Michigan, Ph.D. Dissertation, 2014

  • Perturbation analysis of ionization oscillations in Hall effect thrusters

    K. Hara, M.J. Sekerak, I.D. Boyd, and A.D. Gallimore

    Physics of Plasmas, Vol. 21, Issue. 20, pg. 122103, 2014

  • Mode transition of a Hall thruster discharge plasma

    K. Hara, M.J. Sekerak, I.D. Boyd, and A.D. Gallimore

    Journal of Applied Physics, Vol. 115, Issue 20, pg. 203304, 2014

  • Experimental Evidence for Ion Acoustic Solitons in the Plume of a Hollow Cathode

    Georgin, M.P., Jorns, B.A., and Gallimore, A.D.

    2nd Space Propulsion Conference, Sevilla, Spain, SPC18-403, May 14-18, 2018

  • Non-Invasive Characterization of the Ionization Region of a Hall Effect Thruster

    Dale, E.T. and Jorns, B.A.

    54th AIAA/SAE/ASEE Joint Propulsion Conference, Cincinnati, OH, AIAA-2018-4508, July 9-11, 2018

  • Frequency Scaling of the Hall Thruster Breathing Mode

    Dale, E.T., and Jorns, B.

    AIAA Propulsion and Energy 2019 Forum, Indianapolis, IN, AIAA-2019-4076, August 19-22, 2019

  • Two-zone Hall thruster breathing mode mechanism, Part I: Theory

    Dale, E.T., and Jorns, B.A.

    36th International Electric Propulsion Conference, Vienna, Austria, IEPC-2019-354, 2019

  • Two-zone Hall thruster breathing mode mechanism, Part II: Experiment

    Dale, E.T., and Jorns, B.A.

    36th International Electric Propulsion Conference, Vienna, Austria, IEPC-2019-352, 2019

  • Future Directions for Electric Propulsion Research

    Dale, Ethan; Jorns, Benjamin; Gallimore, Alec

    , https://www.mdpi.com/2226-4310/7/9/120/, August 17, 2020

  • Performance of a 9-kW Magnetically-Shielded Hall Thruster with Krypton

    Leanne L. Su , Alexander R. Vazsonyi and Benjamin Jorns

    VIRTUAL, https://arc.aiaa.org/doi/abs/10.2514/6.2020-3617, August 17, 2020

  • Non-Invasive Near-Wall Ion Measurements in a Hall Thruster

    Ethan T. Dale and Benjamin Jorns

    VIRTUAL, https://arc.aiaa.org/doi/abs/10.2514/6.2020-3646, August 17, 2020

  • Experimental measurements of the contribution of plasma turbulence to anomalous collision frequency in a Hall thruster

    Zachariah A. Brown and Benjamin A. Jorns

    AIAA Propulsion and Energy 2021 Forum, https://pepl.engin.umich.edu/pdf/2021_AIAA_PE_Brown.pdf, July 2021

  • Self-consistent implementation of a zero-equation transport model into a predictive model for a Hall effect thruster

    Thomas A. Marks, Alejandro Lopez Ortega, Ioannis G. Mikellides, and Benjamin A. Jorns

    AIAA Propulsion and Energy 2021 Forum, https://pepl.engin.umich.edu/pdf/2021_AIAA_PE_Marks.pdf, August 2021

  • Experimental characterization of Hall thruster breathing mode dynamics

    Ethan T. Dale, Benjamin A. Jorns

    Journal of Applied Physics, https://pepl.engin.umich.edu/pdf/2021_JoAP_Dale.pdf, October 04, 2021