Transport induced by ion-impurity friction in strongly rotating, collisional Tokamak plasma

A moment approach to the transport theory of impure Tokamak plasmas with strong rotation velocity Vφin the Pfirsch-Schlueter regime with constant temperature is presented. Using the moment approach, the general form of friction and viscosity with effects of large rotation and arbitrary impurity concentration is obtained. In particular, corrections to Braginskii's viscous tensor due to the large rotation are found. When Vφ < υthi, strong in/out and up/down poloidal variations of the impurity density in the flux surface, the first-order poloidal flows, the radial particle flux, and the radial flux of toroidal angular momentum are evaluated. Most importantly, a strong ordering parameter Δ ≡ δpiΖ2ν-barii√2/ωti is introduced and found to be essentially a measure of up/down density variation; and a large enough Δ may lead to a bifurcation of the equilibrium poloidal flows. (author)