Fluid theory and simulations of instabilities, turbulent transport and coherent structures in partially-magnetized plasmas of E×B discharges. (16th November 2016)

• Record Type: Journal Article
• Authors: Smolyakov, A I; Chapurin, O; Frias, W; Koshkarov, O; Romadanov, I; Tang, T; Umansky, M; Raitses, Y; Kaganovich, I D; Lakhin, V P
• Is Part Of: Plasma physics and controlled fusion. Volume 59:Number 1(2017:Jan.)
• Publication Date: 2016-11-16
• Subjects: E×B discharges -- instabilties -- turbulence -- anomalous transport -- Hall thrusters -- electric propulsion -- magnetrons; Plasma (Ionized gases) -- Periodicals; Controlled fusion -- Periodicals; 530.44
• DOI: 10.1088/0741-3335/59/1/014041
• Languages: English
• ISSNs: 0741-3335

Abstract

Abstract: Partially-magnetized plasmas with magnetized electrons and non-magnetized ions are common in Hall thrusters for electric propulsion and magnetron material processing devices. These plasmas are usually in strongly non-equilibrium state due to presence of crossed electric and magnetic fields, inhomogeneities of plasma density, temperature, magnetic field and beams of accelerated ions. Free energy from these sources make such plasmas prone to various instabilities resulting in turbulence, anomalous transport, and appearance of coherent structures as found in experiments. This paper provides an overview of instabilities that exist in such plasmas. A nonlinear fluid model has been developed for description of the Simon-Hoh, lower-hybrid and ion-sound instabilities. The model also incorporates electron gyroviscosity describing the effects of finite electron temperature. The nonlinear fluid model has been implemented in the BOUT++ framework. The results of nonlinear simulations are presented demonstrating turbulence, anomalous current and tendency toward the formation of coherent structures.