A Neoclassical Calculation of Toroidal Rotation Profiles in DIII-D

A calculation model based on neoclassical viscosity and on momentum and particle balance was found to predict global momentum confinement times in DIII-D [1,2] and other tokamaks [3]. An extended model [4,5] has now been applied to calculate the radial distribution of toroidal rotation in several DIII-D shots in a variety of energy confinement regimes (L and H mode, ITB, QDB). Calculated toroidal rotation velocities were generally found to over-predict central experimental values by a factor of 1.5 to 5, reducing to a factor of 1.2 to 2 at $\rho\approx\,$0.8-0.9. Calculations are in progress to determine what part of this over-prediction is due to outward momentum convection and what part should be attributed to anomalous transport. The observed improvement in confinement of L-mode and ITB discharges with neon injection was predicted.\par \vspace{0.5em} \noindent [1]~W.M.\ Stacey, and M.~Murakami, Phys.\ Plasmas, $\bf {8}$, 4450 (2001).\par \noindent [2]~W.M.\ Stacey, and J.~Mandrekas, Phys.\ Plasmas $\bf {9}$, 1622 (2002).\par \noindent [3]~W.M.\ Stacey, and D.R.\ Jackson, Phys.\ Fluids $\bf {B, 5}$, 1828 (1993).\par \noindent [4]~W.M.\ Stacey, Phys.\ Plasmas $\bf {11}$, 3096 (2004).\par \noindent [5]~W.M.\ Stacey, Phys.\ Plasmas $\bf {9}$, 3874 (2002).