Electron cyclotron heating and current drive in the TJ-II stellarator
Open Access
- 1 December 1998
- journal article
- Published by IOP Publishing in Plasma Physics and Controlled Fusion
- Vol. 40 (12), 2113-2130
- https://doi.org/10.1088/0741-3335/40/12/010
Abstract
Electron cyclotron resonance heating (ECRH) has become an attractive technique in today's fusion experiments not only as a heating mechanism but also as a diagnostic tool and a way to induce controllable currents through electron cyclotron current drive (ECCD). In this paper we show, using ray tracing simulations, how one can address all these issues with the ECRH system designed for the TJ-II stellarator. This ECRH set up consists of two 500 kW gyrotrons at f = 53.2 Ghz coupled to the plasma through two quasi-optical transmission lines, placed at two stellarator symmetric positions, and equipped with an internal steerable mirror. Using the three-dimensional (3D) Hamiltonian ray tracing code, TRECE, almost full single-pass absorption with localized power deposition is found for both on- and off-axis heating for any magnetic configuration. The simulations also show that it is possible to induce an appreciable ECCD despite the small oblique incidence angles attainable with the movable mirrors because of the rapid variation of the magnetic field direction and strength with the toroidal angle in TJ-II.Keywords
This publication has 16 references indexed in Scilit:
- Beam waveguide for ECRH at TJ-IIInternational Journal of Infrared and Millimeter Waves, 1997
- Kinetic modelling of the ECRH power deposition in W7-ASPlasma Physics and Controlled Fusion, 1997
- Neural network tool for rapid recovery of plasma topologyReview of Scientific Instruments, 1997
- Electron cyclotron emission calculations for TJ-II stellaratorNuclear Fusion, 1996
- Current drive by electron cyclotron waves in stellaratorsPhysics of Fluids B: Plasma Physics, 1992
- Microwave absorption in stellarators with a non-Maxwellian electron distribution functionPhysics of Fluids B: Plasma Physics, 1989
- Studies of a Flexible Heliac ConfigurationFusion Technology, 1988
- Microwave absorption near the first and second harmonics in the flexible heliac TJ-IINuclear Fusion, 1987
- Theory of current drive in plasmasReviews of Modern Physics, 1987
- Current in wave-driven plasmasPhysics of Fluids, 1986