Momentum Confinement in DIII-D Shots with Impurities

摘要

A neoclassical momentum transport model, consisting of gyroviscous and convectivecomponents, is applied to the analysis of momentum confinement in DIII-D experiments with significant impurity content. Good agreement between predicted and measured central rotation speeds and momentum confinement times is obtained, for L-mode (Low mode) discharges with and without neon injection and for an ELMing (Edge-Localized Modes) H-mode (High Mode) discharge. The observed improvement in momentum confinement time with increasing neon impurity content in the L-mode shots can be accounted for by an neoclassical inward convective momentum flux that increases with impurity content.