Investigation of steady-state tokamak issues by long pulse experiments on Tore Supra

Abstract

The main results of the Tore Supra experimental programme in the years 2007-2008 are reported. They document significant progress achieved in the domain of steady-state tokamak research, as well as in more general issues relevant for ITER and for fusion physics research. Three areas are covered: ITER relevant technology developments and tests in a real machine environment, tokamak operational issues for high power and long pulses, and fusion plasma physics. Results presented in this paper include: test and validation of a new, load-resilient concept of ICRH antenna and of an inspection robot operated under ultra-high vacuum and high temperature conditions; an extensive experimental campaign (5 h of plasma) aiming at deuterium inventory and carbon migration studies; real-time control of sawteeth by ECCD in the presence of fast ion tails; ECRHassisted plasma startup studies; dimensionless  scalings of transport and turbulence; transport experiments using active pertubation methods; resistive and fast-particle driven MHD studies. The potential role of Tore Supra in the worldwide fusion programme before the start of ITER operation is also discussed.

On physical interpretation of two dimensional time-correlations regarding time delay velocities and eddy shaping

“…It is shown that the link between TDE velocity and convective eddy velocity is completely determined by the local statistical shape of the eddies. A straighforward illustration is proposed from data collected by probes arrays in Tore Supra scrape-off layer plasmas 24 . Then, a method is exposed to identify analytic parameters that describe this shape, which are then used to infer the convective eddy velocity from time delays.…”

Plasma regimes and research goals of JT-60SA towards ITER and DEMO

“…From the view point of burning plasma development, which is the main mission of ITER, satellite devices are required to support ITER by resolving its R&D issues [7,8] with flexible exploration of fusion plasma experiments in the ITER-relevant plasma parameter (such as the non-dimensional parameters) regime. The tokamak devices in the world have been contributing to these ITER and DEMO related issues and constructing reliable physics basis; such as in JET [9], JT-60U [10], DIII-D [11], ASDEX-U [12] for highly integrated plasma performance, Tore Supra [13] for long pulse operation, Alcator C-Mod [14] and FTU [15] for high-density physics, MAST [16], NSTX [17] and TCV [18] for plasma shaping physics. Based on these experimental achievements and assessment of research needs for ITER and DEMO, the JT-60SA device and its research project have been designed.…”

Recent Progress in Plasma Control Studies on the Improvement of Plasma Performance in Heliotron J

“…Fueling and recycling control is one of the key issues to obtain high density and high performance plasma in magnetic confinement devices from two aspects; (1) profile control of core plasma and (2) reduction of neutrals in the peripheral region. A supersonic molecular-beam injection (SMBI) technique is considered to be not only an effective fueling method for deeper penetration of neutral particles into the core plasma compared to the conventional gas-puffing 4 (GP) [8] but also an effective edge modification technique in fusion devices [9,10,11] . In Heliotron J, fueling control studies have been performed with high-pressure SMBI.…”