Project

Stability Analysis of Hollow Cathodes


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

project 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


  • 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

  • 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

  • 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