Non-Local Simulation of the Formation of Neoclassical Ambipolar Electric Field in Non-Axisymmetric Configurations

Neoclassical transport simulation code (FORTEC-3D) applicable to non-axisymmetric configurations is developed. A new hybrid simulation model in which ion transport is solved by using the δ f Monte-Carlo method including the finite-orbit-width effects, while electron transport is solved by a reduced ripple-averaged kinetic equation, is adopted. This model makes it possible to simulate the dynamism of non-local transport phenomena with a self-consistently developing radial electric field within an allowable computation time. Time evolution of a radial electric field in LHD plasma is simulated in the full volume of the confinement region, and the finiteorbit-width effect of neoclassical transport is found to make the negative ambipolar electric field larger than that predicted by local transport theory.