On thermionic emission from plasma-facing components in tokamak-relevant conditions.

0476156 - ÚFP 2018 RIV GB eng J - Journal Article
Komm, Michael - Ratynskaia, S. - Tolias, P. - Cavalier, Jordan - Dejarnac, Renaud - Gunn, J. P. - Podolník, Aleš
On thermionic emission from plasma-facing components in tokamak-relevant conditions.
Plasma Physics and Controlled Fusion. Roč. 59, č. 9 (2017), č. článku 094002. ISSN 0741-3335. E-ISSN 1361-6587
R&D Projects: GA ČR(CZ) GA16-14228S; GA MŠMT(CZ) 8D15001
EU Projects: European Commission(XE) 633053 - EUROfusion
Institutional support: RVO:61389021
Keywords : thermionic * PIC * tungsten * tokamak * thermionic emission * plasma facing components * particle-in-cell
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 3.032, year: 2017
http://iopscience.iop.org/article/10.1088/1361-6587/aa78c4/pdf

The first results of particle-in-cell simulations of the electrostatic sheath and magnetic pre-sheath of thermionically emitting planar tungsten surfaces in fusion plasmas are presented. Plasma conditions during edge localized modes (ELMs) and during inter-ELM periods have been considered for various inclinations of the magnetic field and for selected surface temperatures. All runs have been performed under two assumptions for the sheath potential drop, fixed or floating. The primary focus lies on the evaluation of the escaping thermionic current and the quantification of the suppression due to the combined effects of space-charge and Larmor gyration. When applicable, the results are compared with the predictions of analytical models. The heat balance in the presence of thermionic emission as well as the contribution of the escaping thermionic current to surface cooling are also investigated. Regimes are identified where emission needs to be considered in the energy budget
Permanent Link: http://hdl.handle.net/11104/0272724