Edge plasma density convection during ICRH on Tore Supra
The 2D edge plasma density distribution around ion cyclotron resonance heating (ICRH) antennae is studied experimentally and numerically in the tokamak Tore Supra (TS). A local density decrease in front of the loaded ICRH antenna (pump-out effect) is demonstrated by Langmuir probe measurements in a low recycling regime. An up-down asymmetry in the heat flux and in the antenna erosion is also observed, and is associated with poloidal variations of the local density. These density redistributions are ascribed to an ExB convection process linked with RF-sheaths. To assess this interpretation, the 2D transport code CELLS was developed for modelling the density distribution near an antenna. The code takes into account perpendicular diffusion, parallel transport and convection in RF-sheath-driven potentials given by the 3D-antenna code ICANT. The strong density differences obtained in simulations reproduce up-down asymmetries of the heat fluxes.
Bibliographic Reference: Report: EUR-CEA-FC-1721 (2001), pp.35
Record Number: 200114175 / Last updated on: 2001-12-21
Original language: en
Available languages: en