| Autor: |
Victor Désangles, Sergey Shcherbanev, Thomas Charoy, Noé Clément, Clarence Deltel, Pablo Richard, Simon Vincent, Pascal Chabert, Anne Bourdon |
| Jazyk: |
angličtina |
| Rok vydání: |
2020 |
| Předmět: |
|
| Zdroj: |
Atmosphere, Vol 11, Iss 5, p 518 (2020) |
| Druh dokumentu: |
article |
| ISSN: |
2073-4433 |
| DOI: |
10.3390/atmos11050518 |
| Popis: |
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. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
|
