Neoclassical calculations for W7-X OP1.1 parameters
POSTER
Abstract
Neoclassical calculations are carried out for W7-X OP1.1 plasmas with the SFINCS code, using experimental profiles of $n_{\mathrm{e}}$, $T_{\mathrm{e}}$, and $T_{\mathrm{i}}$. An electron root solution is found in the inner part of the plasma, consistent with measurements. Calculations are performed using a variety of assumptions for the plasma's impurity composition. Impurities modestly reduce the bootstrap current, and if a flat $Z_{\mathrm{eff}}$ profile is assumed, the impurity particle flux profile resembles the $E_{r}$ profile due to dominance of the associated thermodynamic force. Variations of quantities on flux surfaces computed with SFINCS are also presented. The incompressible-ExB approximation is found to be quite accurate for W7-X parameters.