Progress of High-Beta Experiments in Stellarator/Heliotron

Journal Article · Thu Jul 15 00:00:00 EDT 2004 · Fusion Science and Technology

OSTI ID:20849716

Watanabe, Kiyomasa Y ^[1]; Weller, Arthur ^[2]; Sakakibara, Satoru ^[1]; Narushima, Yoshiro ^[1]; Ohdachi, Satoshi ^[1]; Narihara, Kazumichi ^[1]; Tanaka, Kenji ^[1]; Ida, Katsumi ^[1]; Toi, Kazuo ^[1]; Yamada, Hiroshi ^[1]; Suzuki, Yasuhiro ^[3]; Kaneko, Osamu ^[1]

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1. National Institute for Fusion Science (Japan)
2. Max-Planck-Institut fuer Plasmaphysik (Germany)
3. Graduate School of Energy Science (Japan)

Recently, dramatic progress has been achieved in the study of helical systems with high-beta experiments. Discharges with more than 3% beta plasmas have been achieved in Large Helical Device (LHD) and Wendelstein 7-AS (W7-AS). Although magnetohydrodynamic (MHD) instabilities affect local pressure gradients, the global transport property does not seem to limit the achieved beta value in either device. We summarize the LHD high-beta properties in MHD stability, equilibrium, and transport, and we show the relationship between the experimentally achieved parameters and theoretical predictions. We contrast the LHD results with the W7-AS high-beta properties. In both devices, stationary discharges in the definitely MHD unstable region have not been observed. We mention the key issue for achievement of the beta values >5%.

• OSTI ID: 20849716
• Journal Information: Fusion Science and Technology, Vol. 46, Issue 1; Other Information: Copyright (c) 2006 American Nuclear Society (ANS), United States, All rights reserved. http://epubs.ans.org/; Country of input: International Atomic Energy Agency (IAEA); ISSN 1536-1055
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
EQUILIBRIUM
HELIOTRON
HIGH-BETA PLASMA
LHD DEVICE
MAGNETOHYDRODYNAMICS
PLASMA MACROINSTABILITIES
PRESSURE GRADIENTS
RADIATION TRANSPORT
WENDELSTEIN-7 STELLARATOR