Towards a general scaling of the Scrape-off Layer density width

0474109 - ÚFP 2018 RIV PT eng C - Conference Paper (international conference)
Carralero, D. - Sun, H.J. - Artene, S.A. - Manz, P. - Müller, H.W. - Groth, M. - Komm, Michael - Adámek, Jiří - Aho-Mantila, L. - Birkenmeier, G. - Brix, M. - Stroth, U. - Vianello, N. - Viezzer, E. - Wischmeier, M. - Wolfrum, E.
Towards a general scaling of the Scrape-off Layer density width.
EPS 2015:42nd European Physical Society Conference on Plasma Physics. Vol. 39E. Mulhouse: European Physical Society, 2015, č. článku O2.106. Europhysics Conference Abstracts, ECA, 39E. ISBN 2-914771-98-3.
[EPS 2015 Conference on Plasma Physics/42./. Lisbon (PT), 22.06.2015-26.06.2015]
EU Projects: European Commission(XE) 633053 - EUROfusion
Institutional support: RVO:61389021
Keywords : Scrape-off Layer * ITER * COMPASS * tokamak
OECD category: Fluids and plasma physics (including surface physics)

The width of the Scrape-off Layer –defined here as the typical radial distance travelled by particles ejected at the separatrix before hitting some PFC- is a key feature for next generation tokamaks, as it will determine erosion levels and heat loads at many critical
plasma facing components, and most critically at the main chamber first wall. Recent Lmode experiments carried out on the ITER stepladder (including COMPASS, ASDEX Upgrade and JET tokamaks) [1] have proven the link between an increase in filament size
at the outer midplane and the onset of the density profile flattening known as “shoulder” [2-4]. This study indicates that the increased effective collisionality, Ldiv, [5,6] in the divertor region at the onset of detachment leads to a change in the regime of filamentary propagation, greatly enhancing radial particle and heat transport. This has been explained as the effect of filament disconnection from the wall: when collisionality along the field line increases over a certain value, the parallel term of the charge conservation equation becomes negligible and the filament goes from Sheath Limited (SL) regime [7] to Inertial (IN) regime [8]. In order to refine the findings in [1] and confirm the validity of this model, a series of dedicated experiments have been carried out in AUG.

Permanent Link: http://hdl.handle.net/11104/0271228