A simple linear diffusive/convective model is proposed for helium transport in the edge plasma of a tokamak reactor. Kinetic effects related to weak collisionality of the plasma are assessed. Results of two-dimensional numerical modelling of helium transport in the edge plasma are presented. Issues of ITER divertor optimization with respect to helium exhaust are considered, with a realistic geometry of the divertor plates taken into account.
Theory and Modelling of Helium Enrichment in Plasma Experiments with Pump Limiters