Fast Camera Analysis of Plasma Instabilities in Hall Effect Thrusters Using a POD Method under Different Operating Regimes

Atmosphere

卷:11

Pablo Richard¹  Clarence Deltel¹  Anne Bourdon¹  Victor Désangles¹  Pascal Chabert¹  Thomas Charoy¹  Sergey Shcherbanev¹  Noé Clément¹  Simon Vincent² 

[1] Laboratoire de Physique des Plasmas, CNRS, Ecole Polytechnique, Sorbonne Université, Université Paris-Sud, Observatoire de Paris, Université Paris-Saclay, PSL Research University, F-91128 Palaiseau, France;

[2] Laboratoire de Physique, University Lyon, Ens de Lyon, University Claude Bernard, CNRS, F-69342 Lyon, France;

关键词: electric propulsion;    plasma instabilities;    HET regime;    HET oscillatory phenomenon;    proper orthogonal decomposition (POD);   

DOI  :  10.3390/atmos11050518

来源: DOAJ

【 摘 要 】

Even after half a century of development, many phenomena in Hall Effect Thrusters are still not well-understood. While numerical studies are now widely used to study this highly non-linear system, experimental diagnostics are needed to validate their results and identify specific oscillations. By varying the cathode heating current, its emissivity is efficiently controlled and a transition between two functioning regimes of a low power thruster is observed. This transition implies a modification of the axial electric field and of the plasma plume shape. High-speed camera imaging is performed and the data are analysed using a Proper Orthogonal Decomposition method to isolate the different types of plasma fluctuations occurring simultaneously. The low-frequency breathing mode is observed, along with higher frequency rotating modes that can be associated to rotating spokes or gradient-induced instabilities. These rotating modes are observed while propagating outside the thruster channel. The reduction of the cathode emissivity beyond the transition comes along with a disappearance of the breathing mode, which could improve the thruster performance and stability.

【 授权许可】

Unknown