Anomalous resistivity of a toroidal plasma in the presence of magnetic turbulence
The impact of anomalous radial diffusion due to turbulent magnetic fields on the electrical conductivity of a toroidal plasma is investigated. The problem is solved by evaluating an appropriate 3-dimensional response function for the current density. This yields an analytical expression of the turbulent electrical conductivity including trapped particle effects. The conductivity is generally enhanced in the pressure gradient region, with respect to the neoclassical one. This results in an anomalously low plasma resistance, a trend observed in many tokamak experiments. The analytical expression found here is shown to be in very good agreement with numerical calculations using a 3-D bounce-averaged Fokker-Planck code. By a similar method, the toroidal response function for RF current drive in the presence of magnetic turbulence is also found.
Bibliographic Reference: Report: EUR-CEA-FC-1461 EN (1992)
Availability: Available from CEA, Département de Recherches sur la Fusion Contrôlée, Centre d'Etudes de Cadarache, 13108 Saint-Paul-lez-Durance (FR), as EUR-CEA-FC-1461, 1992
Record Number: 199211317 / Last updated on: 1994-11-29
Original language: en
Available languages: en