Particle-in-cell simulation of power coupling of the grill of the KSTAR 5.0-GHz LHCD launcher

Abstract

The 5.0-GHz, 2.0-MW KSTAR, Lower-Hybrid Current Drive (LHCD) system is under design for steady-state operation of the KSTAR, tokamak. The launcher structure is designed as a grill (4 rows by 32 columns

phased-array waveguide structure) that provides asymmetric power spectra. The KSTAB. tokamak plasma is a high-density and high-temperature plasma with an edge density of similar to 10(18) m(-3). The power coupling to the KSTAR plasma edge depends on the impedance matching between the grill assembly and the lower hybrid (LH) wave in the edge plasma. The coupling and the wave propagation in the KSTAB, plasma are investigated using the 2-dimensional Particle-In-Cell code (XOOPIC-2D code). This paper describes the preliminary result of the LH power-coupling calculation and the characteristics of the wave propagation.