Calculation of electrostatic fields in vapour shields evolving at ablating surfaces
When a solid surface is directly exposed to the intense energy flux carried by hot incident plasma particles (divertor plates in tokamaks, pellets injected into plasmas), the surface begins to evaporate (ablate). In a relatively short time, a high-density and relatively cold partially ionised cloud forms at the surface, which intercepts at least a fraction of the energy carriers originating from the plasma and penetrating the cloud. Three phenomena are considered in connection with the problem of electrostatic shielding of eroding materials bombarded by magnetically confined plasma particles: (i) the potential jump at the hot plasma-cold vapour interface; (ii) the electric field distribution in the interior of the vapour layer; (iii) the boundary conditions which the electric field must satisfy at the eroding wall.
Bibliographic Reference: Report: IPP 5/53 EN (1993)
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199311643 / Last updated on: 1994-11-28
Original language: en
Available languages: en