[Table of Contents]

Plasma and Fusion Research

Volume 7, 2403113 (2012)

Regular Articles

Reduced-Size LHD-Type Fusion Reactor with D-Shaped Magnetic Surface
Tsuguhiro WATANABE
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 6 December 2011 / Accepted 12 June 2012 / Published 13 September 2012)


A new winding law for the continuous helical coils is proposed for Large Helical Device (LHD) type fusion reactors to satisfy the requirements for a wide blanket space and large plasma volume. Helical coils wound along the geodesic line of a torus with an elongated cross section can produce a magnetic configuration having a D-shaped magnetic surface with a magnetic well in the core region and high magnetic shear in the peripheral regions. The DT alpha particle confinement performance is greatly improved by increasing the elongation factor κ of the cross section of the winding frame for the helical coils. The results suggest that a smaller LHD-type fusion reactor can be realized.


LHD, fusion reactor, helical system, geodesic winding

DOI: 10.1585/pfr.7.2403113


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This paper may be cited as follows:

Tsuguhiro WATANABE, Plasma Fusion Res. 7, 2403113 (2012).