Adhesion force of W dust on tokamak W plasma-facing surfaces: The importance of the impact velocity

The adhesion of tungsten (W) dust particles on W tokamak plasma-facing surfaces is investigated. When spherical dust hits the tokamak walls, its shape is altered as a contact area is created by the adhesion work and irreversible plastic deformation. The van der Waals adhesion force between such a de...

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Bibliographic Details
Main Authors: A. Autricque, F. Gensdarmes, S. Peillon, M. Sow, C. Grisolia
Format: Article
Language:English
Published: Elsevier 2019-01-01
Series:Nuclear Materials and Energy
Online Access:http://www.sciencedirect.com/science/article/pii/S2352179118303089
Description
Summary:The adhesion of tungsten (W) dust particles on W tokamak plasma-facing surfaces is investigated. When spherical dust hits the tokamak walls, its shape is altered as a contact area is created by the adhesion work and irreversible plastic deformation. The van der Waals adhesion force between such a deformed grain and a flat surface is estimated, and the link between the force and the impact velocity is determined. We show that adhesion can be increased by several orders of magnitude when the impact velocity approaches the adhesion velocity. Finally, the effects of surface roughness are incorporated.
ISSN:2352-1791