Project

Stability Analysis of Hollow Cathodes


A hollow cathode operating with a cylindrical anode the emulates a Hall thruster magnetic field.

principal investigator
Benjamin Jorns

former personnel
Marcel Georgin

project sponsors
NASA

Hollow cathodes are used as the electron source for Hall and ion thrusters, but also exhibit complicated dynamic behavior by themselves. The current carrying nature of the cathode plasma can generate instabilities that are believed to be fundamentally important to the operation of Hall thrusters. Other instabilities in the cathode plume can generate high energy ions causing erosion of the device which may limit the lifetime of a thruster. This project aims to improve our understanding of how instabilities in the hollow cathode may influence thruster performance and lifetime. To accomplish this goal, a combination of high-speed probes and imaging, as well as time-resolved laser diagnostics are used to measure wave properties.

A cathode firing in the CTF.

A cathode running at 15 A in the plume mode, imaged at 300 kfps.

Transition of a cathode from spot mode to plume mode.

Selected Publications


  • Low-current Hollow Cathode Evaluation

    Domonkos, M.T., Gallimore, A.D., Williams, G.J., and Patterson, M.J.

    35th Joint Propulsion Conference, Los Angeles, CA, AIAA-99-2575, June 1999

  • Laser Induced Fluorescence Characterization of Ion Emitted from Hollow Cathodes

    Williams, G.J., Smith, T.B., Domonkos, M.T., Shand, K.J., Gallimore, A.D., and Drake, R.P.

    35th Joint Propulsion Conference, Los Angeles, CA, AIAA-99-2862, June 1999

  • Simple Model for Cathode Coupling Voltage Versus Background Pressure in a Hall Thrusters

    Cusson, S.E., Jorns, B.A., and Gallimore, A.D.

    Atlanta, GA, AIAA-2017-4889, 2017

  • Passive High-speed Imaging of Ion Acoustic Turbulence in a Hollow Cathode

    Georgin, M.P., Byrne, M.P., Ciaston, N.E., Jorns, B.A., and Gallimore, A.D

    Atlanta, GA, AIAA-2017-4973, 2017

  • Numerical investigation of the stability criteria for the breathing mode in Hall Effect Thrusters

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

    35th International Electric Propulsion Conference, Atlanta, GA, IEPC-2017-265, 2017

  • An Experimental and Theoretical Study of Hollow Cathode Plume Mode Oscillations

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

    35th International Electric Propulsion Conference, Atlanta, GA, IEPC-2017-298, 2017

  • Hollow cathode simulations with a first-principles model of ion-acoustic anomalous resistivity

    Lopez Ortega, A., Jorns, B.A., and Mikellides, I.G.

    Journal of Propulsion and Power, Vol. 34, No. 4, 10.2514/1.B36782, July-August 2018

  • Plasma Instabilities in the Plume of a Hollow Cathode

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

    54th AIAA/SAE/ASEE Joint Propulsion Conference, Cincinnati, OH, AIAA-2018-4427, July 9-11, 2018

  • Ion heating measurements on the centerline of a high-current hollow cathode plume

    Dodson, C.A., Perez-Grande, D., Jorns, B.A., Goebel, D.M., and Wirz, R.E.

    Journal of Propulsion and Power, Vol. 34, No. 5, 10.2514/1.B36788, September-October 2018

  • Measurements of ion velocity and wave propagation in a hollow cathode plume

    C. Dodson, B.A. Jorns, and R.E. Wirz

    Plasma Sources Science and Technology, [accepted], 2019

  • Recent progress in research and development of hollow cathodes for electric propulsion

    D.R. Lev, I.G. Mikellides, D. Pedrini, D.M. Goebel, B.A. Jorns, and M.S. McDonald

    Reviews of Modern Plasma Physics, (2019) 3:6

  • Time-varying Non-classical Collisions and Turbulence in a Hollow Cathode

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

    AIAA Propulsion and Energy 2019 Forum, Indianapolis, IN, AIAA-2019-4079, August 19-22, 2019

  • Correlation of ion acoustic turbulence with self-organization in a low-temperature plasma

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

    Physics of Plasmas, Vol. 26, Issue 8, 082308, 2019

  • Onset criterion for a turbulence-driven ionization instability in hollow cathodes

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

    36th International Electric Propulsion Conference, Vienna, Austria, IEPC-2019-155, 2019

  • Dependence of Low Frequency Waves on Magnetic Field Strength in Hollow Cathode Plume

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

    36th International Electric Propulsion Conference, Vienna, Austria, IEPC-2019-249, 2019

  • Non-classical electron transport in the cathode plume of a Hall effect thruster

    Benjamin A. Jorns, Sarah E. Cusson, Zachariah Brown, and Ethan Dale

    Physics of Plasmas, 27, 022311, 18 February 2020

  • Transient non-classical transport in the hollow cathode plume I: measurements of time-varying electron collision frequency

    Georgin, Marcel P; Jorns, Benjamin A. Gallimore, Alec D

    University of Michigan, http://pepl.engin.umich.edu/pdf/2020_PSST_Georgin.PDF, 2020

  • Transient non-classical transport in the hollow cathode plume II: evaluation of models for the anomalous collision frequency

    Georgin, Marcel P; Jorns, Benjamin A.

    University of Michigan, http://pepl.engin.umich.edu/pdf/2020_PSST_Georgin_II.PDF, 2020

  • Perspectives on Physics of ExB Discharges Relevant to Plasma Propulsion and Similar Technologies

    Kaganovich, Igor D. et al

    University of Michigan, http://pepl.engin.umich.edu/pdf/2020_PoP_Kaganovich_et_al.PDF, 2020

  • Model for the dependence of cathode voltage in a Hall thruster on facility pressure

    Benjamin Jorns and Matthew Byrne

    University of Michigan, http://pepl.engin.umich.edu/pdf/2021_PSST_Jorns.PDF, 2020

  • Rotational Waves in the Plume of an Externally-Mounted Hall Thruster Cathode

    Shadrach Hepner, Edward Tang, Ethan Dale, and Benjamin A Jorns

    AIAA Journal of Propulsion and Power, https://pepl.engin.umich.edu/pdf/2021_AIAA_Hepner.pdf, August 5, 2021

  • Experimental Characterization of Wave-Induced Azimuthal Ion Velocities in a Hollow Cathode Plume

    Parker J. Roberts, Benjamin A. Jorns, and Vernon H. Chaplin

    AIAA SciTech 2022, https://pepl.engin.umich.edu/pdf/2022_AIAA_ST_Roberts.pdf, January 2022