Dynamics of heavy impurities in non-linear MHD simulations of sawtoothing tokamak plasmas

Jae-H Ahn (1) , Xavier Garbet (1) , H Lütjens (2) , R Guirlet (1)

1 IRFM - Institut de Recherche sur la Fusion par confinement Magnétique
2 CPHT - Centre de Physique Théorique [Palaiseau]

The effect of sawteeth on impurity dynamics is studied with the XTOR-2F code. Non-linear full 3D MHD simulations including appropriate fluid equations for heavy impurities show that the presence of regular sawtooth crashes affects the impurity behaviour. A spatial non-uniformity of 5% in post-crash impurity density profiles persists due to 2D structures of impurity density which appear during sawtooth crashes. They are shown to be mainly driven by the E × B velocity, and are responsible for the sudden impurity transport in the core plasmas.

Mots clés: Sawtooth instability; Impurity; Simulation 3D

Domaines: Physique des plasmas [physics.plasm-ph]

Jae-H Ahn, Xavier Garbet, H Lütjens, R Guirlet. Dynamics of heavy impurities in non-linear MHD simulations of sawtoothing tokamak plasmas. 2016. ⟨hal-01340291⟩