Fusion Science and Technology / Volume 57 / Number 2T / February 2010 / Pages 330-338
Transport Theory / Proceedings of the Ninth Carolus Magnus Summer School on Plasma and Fusion Energy Physics
The classical transport theory is strictly valid for a plasma in a homogeneous and stationary magnetic field. In the '60, experiments have shown that this theory does not apply as a local theory of transport in Tokamaks. It was shown that global geometric characteristics of the confining elements have a strong influence on the transport. Three regimes of collisionality are characteristic of the neoclassical transport theory: the banana regime (the electronic diffusion coefficient increases starting from zero), the plateau regime (the diffusion coefficient is almost independent of the collisionality) and the Pfirsch-Schlüter regime (the electronic diffusion coefficient again increases with collisionality).