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.
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.
Simple Model for Cathode Coupling Voltage Versus Background Pressure in a Hall Thrusters
Cusson, S.E., Jorns, B.A., and Gallimore, A.D.
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
Numerical investigation of the stability criteria for the breathing mode in Hall Effect Thrusters
Dale, E.T., Jorns, B., and Hara, K.
An Experimental and Theoretical Study of Hollow Cathode Plume Mode Oscillations
Georgin, M.P., Jorns, B.A., Gallimore, A.D.
Hollow cathode simulations with a first-principles model of ion-acoustic anomalous resistivity
Lopez Ortega, A., Jorns, B.A., and Mikellides, I.G.
Plasma Instabilities in the Plume of a Hollow Cathode
Georgin, M.P., Jorns, B.A., and Gallimore, A.D.
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.
Measurements of ion velocity and wave propagation in a hollow cathode plume
C. Dodson, B.A. Jorns, and R.E. Wirz
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
Time-varying Non-classical Collisions and Turbulence in a Hollow Cathode
Georgin, M.P., Jorns, B., and Gallimore, A.
Correlation of ion acoustic turbulence with self-organization in a low-temperature plasma
M.P. Georgin, B.A. Jorns, and A.D. Gallimore
Onset criterion for a turbulence-driven ionization instability in hollow cathodes
Georgin, M.P., Jorns, B.A., Gallimore, A.D.
Dependence of Low Frequency Waves on Magnetic Field Strength in Hollow Cathode Plume
Georgin, M.P., Jorns, B.A., Gallimore, A.D.
Non-classical electron transport in the cathode plume of a Hall effect thruster
Benjamin A. Jorns, Sarah E. Cusson, Zachariah Brown, and Ethan Dale
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
Transient non-classical transport in the hollow cathode plume II: evaluation of models for the anomalous collision frequency
Georgin, Marcel P; Jorns, Benjamin A.
Perspectives on Physics of ExB Discharges Relevant to Plasma Propulsion and Similar Technologies
Kaganovich, Igor D. et al
Model for the dependence of cathode voltage in a Hall thruster on facility pressure
Benjamin Jorns and Matthew Byrne
Rotational Waves in the Plume of an Externally-Mounted Hall Thruster Cathode
Shadrach Hepner, Edward Tang, Ethan Dale, and Benjamin A Jorns
Experimental Characterization of Wave-Induced Azimuthal Ion Velocities in a Hollow Cathode Plume
Parker J. Roberts, Benjamin A. Jorns, and Vernon H. Chaplin