Transport Modeling of Edge Plasma in an m/n=1/1 Magnetic Island

Recent Large Helical Device experiments show that the transport modeling based only on the fluid description is not sufficient for expressing transport phenomena in/around an m/n = 1/1 magnetic island formed at the edge, and that neoclassical effect should be considered in order to understand the edge transport phenomena, where m is the poloidal mode number and n the toroidal mode number. To study the edge transport phenomena, we develop a new transport simulation code, KEATS, treating the neoclassical theory in/around the island. The code is programmed by expanding a well-known Monte-Carlo particle simulation scheme based on the δf method for taking account of the neoclassical effect. In the modeling used in the KEATS code, evolution of the local Maxwellian background fM described by fluid equations is considered self-consistently with the kinetic part δf. In this paper, we present the modeling used in the KEATS code, and show the simulation results in a test calculation. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)