Skip to Main content Skip to Navigation
Theses

Numerical study of electron transport in Hall thrusters

Abstract : In the last decade, the number of satellites orbiting around Earth has grown exponentially. Thanks to their low propellant consumption, more and more electric thrusters are now used aboard these satellites, with the Hall thrusters being one of the most efficient. From the diversity of applications stems the need of widening the thruster power capabilities. However, due to a lack of knowledge on Hall thruster physics, this scaling is currently done empirically, which limits the efficiency of the newly developed thrusters and increases the development time and cost. To overcome this issue, numerical models can be used but a deeper understanding on key phenomena is still needed, more specifically on the electron anomalous transport which should be self-consistently accounted for to properly capture the discharge behaviour.As this transport is related to the azimuthal electron drift instability, an existing 2D Particle-In-Cell code was further developed to simulate this azimuthal direction along with the axial direction in which the ions are accelerated, producing the thrust. Prior to analyse the discharge behaviour, this code has been verified on a benchmark case, with 6 other PIC codes developed in different international research groups. This simplified case was later used to stress-test previous analytical developments to approximate the instability-enhanced electron-ion friction force which represents the contribution of the azimuthal instabilities to the anomalous transport. Then, the neutral dynamics has been included to capture the full self-consistent behaviour of the discharge. We used an artificial scaling technique, increasing the vacuum permittivity, to relax the PIC stability constraints and speed-up the simulations. Thanks to an efficient code parallelisation, we managed to reduce this scaling factor to a small value, hence simulating a case close to reality. The electron-ion friction force was found to be the main contributor to the anomalous transport throughout the whole low-frequency breathing mode oscillations. Finally, the complex interaction between the breathing mode, the ion-transit time instabilities and the azimuthal electron drift instabilities has been studied, with the formation of long-wavelength structures associated with an enhanced anomalous transport.
Complete list of metadatas

Cited literature [238 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02982367
Contributor : Abes Star :  Contact
Submitted on : Wednesday, October 28, 2020 - 3:43:21 PM
Last modification on : Monday, November 2, 2020 - 11:05:27 AM

File

91113_CHAROY_2020_archivage.pd...
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02982367, version 1

Citation

Thomas Charoy. Numerical study of electron transport in Hall thrusters. Plasma Physics [physics.plasm-ph]. Institut Polytechnique de Paris, 2020. English. ⟨NNT : 2020IPPAX046⟩. ⟨tel-02982367⟩

Share

Metrics

Record views

87

Files downloads

56