Global simulations of ion turbulence with magnetic shear reversal

Autor:	P. Beyer, Sadruddin Benkadda, C. Figarella, I. Voitsekovitch, Olivier Agullo, G. T. Hoang, Patrick Maget, Nicolas Bian, Xavier Garbet, Clarisse Bourdelle
Rok vydání:	2001
Předmět:	Physics Safety factor Tokamak Toroid Turbulence K-epsilon turbulence model Mechanics Condensed Matter Physics Velocity shear law.invention Ion Physics::Fluid Dynamics Classical mechanics Shear (geology) Physics::Plasma Physics law
Zdroj:	Physics of Plasmas. 8:2793-2803
ISSN:	1089-7674 1070-664X
DOI:	10.1063/1.1367320
Popis:	This paper presents the results of three-dimensional fluid global simulations of electrostatic ion turbulence in tokamaks with reversed magnetic shear. It is found that a transport barrier appears at the location of magnetic shear reversal. This is due to a rarefaction of resonant surfaces in this region. For the same reason, the barrier is more pronounced when the minimum of the safety factor is a simple rational number. The barrier is broadened by velocity shear effects. It is also found that large-scale transport events hardly cross a transport barrier. Finally, a significant amount of toroidal rotation is generated by the turbulence. This rotation changes its sign at the position of magnetic shear reversal, as expected from a quasi-linear estimate of the Reynolds stresstensor.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::d84ec7c227b0330dedf0c12ac8ef3e58 https://doi.org/10.1063/1.1367320 Zobrazit plný text záznamu