Theoretical and experimental studies of large scale modes in Hall thrusters and methods of their control
| dc.contributor.advisor | Smolyakov, Andrei | |
| dc.contributor.committeeMember | Koustov, Alexandre | |
| dc.contributor.committeeMember | Xiao, Chijin | |
| dc.contributor.committeeMember | Bradley, Michael | |
| dc.contributor.committeeMember | Kasap, Safa | |
| dc.creator | Romadanov, Ivan 1986- | |
| dc.creator.orcid | 0000-0003-3291-3341 | |
| dc.date.accessioned | 2019-01-25T22:22:34Z | |
| dc.date.available | 2019-01-25T22:22:34Z | |
| dc.date.created | 2019-01 | |
| dc.date.issued | 2019-01-25 | |
| dc.date.submitted | January 2019 | |
| dc.date.updated | 2019-01-25T22:22:34Z | |
| dc.description.abstract | Partially-magnetized plasmas with magnetized electrons and weakly-magnetized ions in crossed electric and magnetic fields are common in the nature and industrial devices, such as magnetrons, MHD generators, electric propulsion (ion/Hall thrusters, helicon thrusters), and Penning discharges. Such plasmas are usually in a strongly non-equilibrium state, exhibiting a variety of turbulent fluctuations. These fluctuations are responsible for anomalous transport phenomena and large-scale plasma structures. This study investigates one of the most known and pervasive examples: rotating spokes and breathing modes, in Hall thrusters. Breathing mode is an m=0 mode (where m is the azimuthal mode number), propagating in the axial direction, and leading to strong oscillations of the discharge current, up to 100 % in amplitude. Spoke is an m=1,2,… mode, rotating in an azimuthal direction and is thought to be responsible for a large part of the anomalous current in a system. These large-scale perturbations can critically affect the performance of Hall thrusters, but the exact nature of these modes is unknown. Both types of oscillations are believed to be induced and strongly affected by the equilibrium electron current due to ExB drift, plasma density gradients, and ionization. This thesis is devoted to theoretical and experimental studies of spoke and breathing mode mechanisms, their coupling, and methods of their control. | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | http://hdl.handle.net/10388/11829 | |
| dc.subject | Hall thruster | |
| dc.subject | low-temperature plasma | |
| dc.subject | instabilities | |
| dc.subject | breathing mode | |
| dc.subject | spoke mode | |
| dc.subject | large-scale structures | |
| dc.subject | ExB drift | |
| dc.subject | space propulsion | |
| dc.subject | electric propulsion | |
| dc.subject | laser-induced fluorescence | |
| dc.subject | plasma control | |
| dc.title | Theoretical and experimental studies of large scale modes in Hall thrusters and methods of their control | |
| dc.type | Thesis | |
| dc.type.material | text | |
| thesis.degree.department | Physics and Engineering Physics | |
| thesis.degree.discipline | Physics | |
| thesis.degree.grantor | University of Saskatchewan | |
| thesis.degree.level | Doctoral | |
| thesis.degree.name | Doctor of Philosophy (Ph.D.) |