Dust remobilization from rough planar surfaces in tokamak steady-state plasmas

A. Autricque (1) , S. Peillon (2) , F. Gensdarmes (2) , Moustapha Sow (3) , N. Fedorczak (1) , H. Roche (1) , O. Pluchery (4) , C. Grisolia

1 IRFM - Institut de Recherche sur la Fusion par confinement Magnétique
2 IRSN - Institut de Radioprotection et de Sûreté Nucléaire
3 LMDC - Laboratoire Matériaux et Durabilité des constructions
4 INSP - Institut des Nanosciences de Paris

The ability of tungsten (W) dust to be remobilized from rough tokamak plasma-facing surfaces is investigated in this study. Atomic Force Microscopy is used to evaluate the adhesion force distribution between W spheroids of µm radius and a rough W substrate. Our results confirm that the Rabinovich model describes reasonably well the mean adhesion force in tokamak-relevant surface roughness regimes. The external (electric and ion drag) forces are estimated as well using a simplified sheath model. The results reveal that micron-size dust can be resuspended by attainable electric fields in tokamak conditions.

Domaines: Physique [physics]

A. Autricque, S. Peillon, F. Gensdarmes, Moustapha Sow, N. Fedorczak, et al.. Dust remobilization from rough planar surfaces in tokamak steady-state plasmas. Nuclear Materials and Energy, 2018, 17 (Décembre 2018), pp.284-288. ⟨10.1016/j.nme.2018.11.013⟩. ⟨hal-01978595⟩