Filamentation, current profiles, and transport in a tokamak

Taylor, J. B.
December 1993
Physics of Fluids B: Plasma Physics;Dec93, Vol. 5 Issue 12, p4378
Academic Journal
A tokamak with slightly imperfect magnetic surfaces should have a microscopically filamented current structure. If so, its equilibrium has an analog in the dynamics of interacting charged rods. Then there will be a natural current profile, analogous to thermal equilibrium of the rods (and the natural profile can be calculated by conventional statistical mechanics). This would account for the phenomenon of profile consistency or resilience in tokamaks. In addition to the natural profiles, this filamentary model also predicts an anomalous inward flux of both heat and particles in a tokamak, as well as an anomalous diffusion. These ‘‘inward-pinch’’ components are related to the current gradient.


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