12-15 July 2011
Saint George Hotel
Africa/Johannesburg timezone

Miniaturization of electrostatic ion engine through ionization/acceleration coupling: corona model

13 Jul 2011, 14:30
15m
Acro3

Acro3

Oral Presentation Track F - Applied and Industrial Physics Applied

Speaker

Mr Marius Tchonang Pokaha (Wits University)

Description

Electrostatic ion propulsion systems resist miniaturization due to constraints imposed by the size of the discharge chamber. We introduce a thruster concept where the same field is responsible for both ionization of the neutrals and acceleration of the ions, by letting the neutral propellant gas escape into a high field region through a thin, hollow needle at high electric potential. The ionization mechanism is thus reminiscent of corona ionization. Although the thruster only ionizes a small fraction of the neutral gas, the ions nevertheless impart a great deal of momentum to the plume, creating an ion wind. We propose a model to estimate the electric behavior of the system, and two further models for the obtained thrust. A comparison with experimental data shows that the models capture the dominant physical effects and give a reasonable description of the system. Apart from being about a thousand times less massive than conventional systems, the thruster, which is at the proof-of-concept stage, performed quite well yielding around 0.3 mN/Watt during initial tests. The thruster small size and simplicity are advantageous in many situations, such as for satellite station keeping and deep space probes.

Level (Hons, MSc, <br> &nbsp; PhD, other)? MSc
Consider for a student <br> &nbsp; award (Yes / No)? yes
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)? yes

Primary author

Mr Marius Tchonang Pokaha (Wits University)

Co-author

Dr Phil Ferrer (Wits University)

Presentation Materials