Hollow Cathode and Low-Thrust Extraction Grid Analysis for a 
                        Miniature Ion Thruster

Wirz, Richard; Sullivan, Regina; Przybylowski, JoHanna; Silva, Mike

doi:https://doi.org/10.1155/2008/693825

International Journal of Plasma Science and Engineering

On this page

Abstract References Copyright Related Articles

Research Article | Open Access

Volume 2008 | Article ID 693825 | https://doi.org/10.1155/2008/693825

Hollow Cathode and Low-Thrust Extraction Grid Analysis for a Miniature Ion Thruster

Richard Wirz,¹Regina Sullivan,²JoHanna Przybylowski,²and Mike Silva²

Academic Editor: Paul K. Chu

Received03 Jan 2008

Revised20 Apr 2008

Accepted23 Jun 2008

Published03 Aug 2008

Abstract

Miniature ion thrusters are well suited for future space missions that require high efficiency, precision thrust, and low contamination in the mN to sub-mN range. JPL's miniature xenon Ion (MiXI) thruster has demonstrated an efficient discharge and ion extraction grid assembly using filament cathodes and the internal conduction (IC) cathode. JPL is currently preparing to incorporate a miniature hollow cathode for the MiXI discharge. Computational analyses anticipate that an axially upstream hollow cathode location provides the most favorable performance and beam profile; however, the hot surfaces of the hollow cathode must be sufficiently downstream to avoid demagnetization of the cathode magnet at the back of the chamber, which can significantly reduce discharge performance. MiXI's ion extraction grids are designed to provide >3 mN of thrust; however, previous to this effort, the low-thrust characteristics had not been investigated. Experimental results obtained with the MiXI-II thruster (a near replica or the original MiXI thruster) show that sparse average discharge plasma densities of ∼5×1015–5×1016 m-3 allow the use of very low beamlet focusing extraction voltages of only ∼250–500 V, thus providing thrust levels as low as 0.03 mN for focused beamlet conditions. Consequently, the thrust range thus far demonstrated by MiXI in this and other tests is 0.03–1.54 mN.

References

R. Wirz, J. Mueller, M. Gale, and C. Marrese, “Miniature ion engine for precision formation flying,” in Proceedings of the 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Fort Lauderdale, Fla, USA, July 2004, AIAA-2004-4115.
View at: Google Scholar
R. Wirz, J. Polk, C. Marrese, and J. Mueller, “Experimental and computational investigation of the performance of a micro-ion thruster,” in Proceedings of the 38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Indianapolis, Ind, USA, July 2002, AIAA-2002-3835.
View at: Google Scholar
R. Wirz, D. Goebel, C. Marrese, and J. Mueller, “Development of cathode technologies for a miniature ion thruster,” in Proceedings of the 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Huntsville, Ala, USA, July 2003, AIAA-2003-4722.
View at: Google Scholar
R. Wirz, Discharge plasma processes of ring-cusp ion thrusters, Ph.D. dissertation, Aeronautics, Caltech, Pasadena, Calif, USA, 2005.
M. T. Domonkos, Evaluation of low-current orificed hollow cathodes, Ph.D. thesis, University of Michigan, Ann Arbor, Mich, USA, 1999.
M. T. Domonkos, A. D. Gallimore, and M. J. Patterson,, “An evaluation of hollow cathode scaling to very low power and flow rate,” in Proceedings of the 25th International Electric Propulsion Conference, Cleveland, Ohio, USA, August 1997, IEPC-97-189.
View at: Google Scholar
M. T. Domonkos, A. D. Gallimore, G. J. Williams, Jr., and M. J. Patterson, “Low-current hollow cathode evaluation,” in Proceedings of the 35th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Los Angeles, Calif, USA, June 1999, AIAA-99-2575.
View at: Google Scholar
R. Wirz and D. Goebel, “Ion thruster discharge performance per magnetic field topography,” in Proceedings of the 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Sacramento, Calif, USA, July 2006, AIAA-2006-4487.
View at: Google Scholar
R. Wirz and I. Katz, “Plasma processes of DC ion thruster discharge chambers,” in Proceedings of the 41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Tucson, Ariz, USA, July 2005, AIAA-2005-3690.
View at: Google Scholar
G. Aston, H. R. Kaufman, and P. J. Wilbur, “Ion beam divergence characteristics of two-grid accelerator systems,” AIAA Journal, vol. 16, no. 5, pp. 516–524, 1978.
View at: Google Scholar
J. R. Brophy, I. Katz, J. E. Polk, and J. R. Anderson, “Numerical simulations of ion thruster accelerator grid erosion,” in Proceedings of the 38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Indianapolis, Ind, USA, July 2002, AIAA-2002-4261.
View at: Google Scholar

Copyright

Copyright © 2008 Richard Wirz et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

469

Downloads

0

Citations