(Georgia Institute of Technology, 2005-10)
Stacey, Weston M.; Johnson, R. W.; Mandrekas, John
Momentum and particle balance and neoclassical viscosity were applied to calculate the radial
profile of toroidal rotation in several DIII-D [J. Luxon, Nucl. Fusion, 42, 614 (2002)] discharges in a
variety of energy confinement regimes (Low-mode, Low-mode with Internal Transport Barrier, Highmode,
and High-mode with Quiescent Double Barrier). Calculated toroidal rotation velocities were found
to over-predict measured values most in the center—by factors of 1.5 to 3--with the over-prediction
generally decreasing with increasing radius, for the L, H and ITB mode shots, but the single impurity
species approximation could not properly model the multiple Ni and Cu charge states in the QDB shots.
(Georgia Institute of Technology, 2005-10)
Zhang, Dingkang; Mandrekas, John; Stacey, Weston M.
Extensions of the 2D Transmission and Escape Probability neutral particle transport method in treating
the spatial non-uniformity of collision sources and neutral energy effects are presented. These extensions
have been tested by benchmarks against Monte Carlo calculations for specially designed models and for
realistic DIII-D discharges. The comparisons indicate these extensions improve accuracy of the TEP
method.