Discussion thread: "Controlling perpendicular electric fields with biased electrodes"

[trotabas]

Hello everyone,
I'm in the last year of my Ph.D. at Laplace Laboratory in Toulouse, studying the control of the perpendicular electric fields with biased electrodes in a magnetized plasma.

My work consists of analyzing the parameters dependencies of the voltage drop across the sheath and along field lines to minimize them. In this way, the electric field imposed via the electrode bias is recovered along the plasma column.

If you are interested in this subject, with my supervisor Renaud Gueroult, we recently published a paper → https://iopscience.iop.org/article/10.1088/1361-6595/ac4847/meta

I'm looking forward to present my work during the poster session,
Best Regards,
Baptiste

[eahedo]

Hi Baptiste, Very interesting work. It raises several questions to me. Some of them:
How do you take into account the plasma in your model?How the sign of the applied field or applied bias affect your solution and, in particular, saturation?Do you envisage to apply it to Hall or other thrusters?

[trotabas]

Thank you for your remark!

The plasma is taken into account through its parallel (sigma_para) and perpendicular (sigma_perp) conductivity; only the perpendicular conductivity is used in analytical models to determine the plasma potential at the sheath edge, whereas sigma_para and sigma_perp are inputs to the anisotropic Laplace solver.

The effect of the electrode bias sign is not obvious...
From my point of view, that is a question related to the loss of particles at the walls. In our paper, an ion sheath is assumed to be present in front of the electrode because the electrode is negatively biased; ions are expected to reach the electrode. If now the electrode is biased positively, what is the dynamic of particles? Do all electrons reach the electrode? Is there a Boltzmann factor that we shall apply to the ion flux?
Nevertheless, as long as an ion sheath is considered, I think the electrode can be biased positively or negatively the electrode.

No, I won't apply those models for Hall thruster, I'm focusing on plasma column.

If you have other questions, don't hesitate :)

[eahedo]

Baptiste, thank you! --------------------- Eduardo Ahedo Professor of Aerospace Engineering Universidad Carlos III de Madrid Avenida Universidad 30, Of. 7.3.H04 28911 Leganés, España +34 91 624 8234 El jue, 17 feb 2022 a las 17:35, BaptisteT ***@***.***>) escribió:

…

Thank you for your remark! The plasma is taken into account through its parallel (sigma_para) and perpendicular (sigma_perp) conductivity; only the perpendicular conductivity is used in analytical models to determine the plasma potential at the sheath edge, whereas sigma_para and sigma_perp are inputs to the anisotropic Laplace solver. The effect of the electrode bias sign is not obvious... From my point of view, that is a question related to the loss of particles at the walls. In our paper, an ion sheath is assumed to be present in front of the electrode because the electrode is negatively biased; ions are expected to reach the electrode. If now the electrode is biased positively, what is the dynamic of particles? Do all electrons reach the electrode? Is there a Boltzmann factor that we shall apply to the ion flux? Nevertheless, as long as an ion sheath is considered, I think the electrode can be biased positively or negatively the electrode. No, I won't apply those models for Hall thruster, I'm focusing on plasma column. If you have other questions, don't hesitate :) — Reply to this email directly, view it on GitHub <#18 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AXZBHFUGBY5VCO2BIW6CJJDU3UPVVANCNFSM5OKVSD2A> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. You are receiving this because you commented.Message ID: <ep2lab/ExB_workshop_2022_website/repo-discussions/18/comments/2198223@ github.com>