Delta f Simulation of Ion Neoclassical Transport

"Ion neoclassical transport with finite orbit width dynamics is calculated over whole poloidal cross section by using accurate delta f method which employs an improved like-particle collision operator and an accurate weighting scheme to solve drift, kinetic equation. Ion thermal transport near magnetic axis shows a great reduction from its conventional neoclassical level due to non-standard orbit topology, like that of previous delta f simulation. On other hand, the direct particle loss from confinement region may strongly increase ion energy transport near the edge. It is found that ion parallel flow near the axis is also largely reduced due to nonstandard orbit topology. In the presence of steep density gradient, ion therma1 conductivity is significantly reduced, and an ion particle flux is driven by self-collision alone.