Pump-out effect in ergodic divertor experiment
One of the striking features of the ergodic divertor experiment, is the decrease of the particle content triggered by the magnetic perturbation. The aim of this paper is to reconsider the radial particle transport in the ergodic layer, by putting emphasis on the self consistent radial electric field. Due to ion mobility, it is shown that the particle field exhibits an outward component driven by the electron temperature gradient, in addition to the usual component driven by the density gradient. This flux component is comparable in absolute value to the inward anomalous pinch velocity in a low temperature plasma. The poloidal modulations of the electron temperature enhance the particle diffusivity. For cold edge plasma this outward component then becomes strong enough to expell particles from the ergodic zone.
Bibliographic Reference: Article: Plasma Physics (1997)
Record Number: 199810160 / Last updated on: 1998-02-12
Original language: en
Available languages: en