Impact of higher-order flows in the moment equations on Pfirsch-Schlter friction coefficients

モーメント方程式中の高次流がフィルシュ・シュリューター係数に及ぼす影響

本多 充

Honda, Mitsuru

In fusion plasmas, the impact of the higher-order flows in the moment approach of the neoclassical transport theory on an estimate of the friction coefficients is examined multilaterally. Their effects have not been consistently taken into account thus far in the widely used neoclassical transport codes based on the moment equations when diffusivities are calculated in the collision-dominated Pfirsch-Schlter regime. Due to the matrix element expressions applicable to arbitrary mass and temperature ratios and the rigorous way of numerically calculating the higher-order flows and the resultant friction coefficients, it is clearly revealed that incorporating the higher-order flow effects precisely is of great importance especially for plasmas including multiple hydrogenic ions and other lighter species with similar masses.