Aachen PK 2003 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

P: Plasmaphysik

P 8: Magnetic Confinement

P 8.4: Vortrag

Dienstag, 18. März 2003, 16:30–16:50, FO2

A theoretical and experimental investigation of edge plasma rotation in TEXTOR. — •Michael Van Schoor, Stefan Jachmich, and Roger Weynants — Laboratoire de Physique des Plasmas-Laboratorium voor Plasmafysica, Association ’Euratom-Belgian state’, Koninklijke Militaire School,Renaissancelaan 30, B-1000 Brussels, Belgium

The plasma edge plays an important role in the physics of improved confinement. The shear in the radial electric field is held responsible for the suppression of turbulence, but neutrals, steep gradients and the curvature of the geometry complicate its study. We have developed a set of experiments and theory to analyse these phenomena

An electric field is set up by way of a biasing electrode and creates highly sheared flows, which reduce the turbulence in the edge and thus improve the confinement.

The rotation velocities are measured with an inclined Mach probe and are then compared with the predictions of a 1D-fluid model. In this model, parallel viscosity and neutral friction are identified as important components, while in the narrow zone, where rotation exists, compressibility effects are observed.

We also show that convection and shear viscosity, have a marked influence on the flows. Without the quenching of the turbulence, and thus the reduction of the importance of the convection and shear viscosity it is impossible to explain the magnitude and the shape of the measured electric field.