Topic/Type: 1.2 Fusion Plasmas (magnetic & inertial confinement), Poster

Simulation study of NBI heating and current drive using NUBEAM and ASTRA codes for KSTAR tokamak

L. Terzolo1, J.M. Kwon1, J.Y. Kim1, Y.S. Na2, T.S. Kim3, B.H. Oh3

1 National Fusion Research Institute, Yusung-ku, Daejeon 305-333, South Korea
2 Department of Nuclear Engineering, Seoul National University, Seoul, South Korea
3 Korea Atomic Energy Research Institute, 150 Deokjin-dong, Yuseong-gu, Daejeon 305-353, South Korea

The KSTAR (Korean Superconducting Tokamak Advanced Reactor) device, which finished successfully the first-plasma experiment last year, aims eventually to demonstrate the steady-state operation of high performance AT (Advanced Tokamak) modes. For this research goal, KSTAR is going to implement several heating and current systems, which include NBI, ICRH, LHCD, and ECH/ECCD systems. In particular, KSTAR plans to implement two types of NBI system for a more flexible plasma profile control; one has an on-axis and the other an off-axis beam direction. Here, we present a simulation study of NBI heating and current drive with the planned KSTAR NBI systems. For the simulation we use two different codes: NUBEAM and a NBI module from ASTRA. NUBEAM is a Monte Carlo code, while the NBI module from ASTRA uses a simplified analytical solution of the steady state Fokker-Planck equation. We consider several operation modes of KSTAR, which include L-, H-, and AT modes, with the two different NBI configurations, and also two different maximum beam energies of 100 and 120 keV. Comparisons are presented between the two different codes with respect to NBI configurations and beam energies for the optimum evaluation and design of the KSTAR NBI system.

Keywords: KSTAR tokamak, NBI, Simulation, NUBEAM, ASTRA