[Table of Contents]

Plasma and Fusion Research

Volume 5, S2055 (2010)

Regular Articles

Magnetohydrodynamic Simulation of Kink Instability and Plasma Flow during Sustainment of a Coaxial Gun Spheromak
Takashi KANKI, Masayoshi NAGATA1) and Yasuhiro KAGEI2)
Department of Maritime Science and Technology, Japan Coast Guard Academy, Kure, Hiroshima 737-8512, Japan
1)
Department of Electrical Engineering and Computer Sciences, University of Hyogo, Himeji, Hyogo 671-2280, Japan
2)
Research Organization for Information Science & Technology, Tokai, Ibaraki 319-1106, Japan
(Received 5 December 2009 / Accepted 15 March 2010 / Published 10 December 2010)

Abstract

Kink instability and the subsequent plasma flow during the sustainment of a coaxial gun spheromak are investigated by three-dimensional nonlinear magnetohydrodynamic simulations. Analysis of the parallel current density λ profile in the central open column revealed that the n = 1 mode structure plays an important role in the relaxation and current drive. The toroidal flow (vt ≈ 37 km/s) is driven by magnetic reconnection occurring as a result of the helical kink distortion of the central open column during repetitive plasmoid ejection and merging.

Keywords

spheromak, coaxial helicity injection, MHD relaxation, kink instability, plasma flow, simulation

DOI: 10.1585/pfr.5.S2055

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References

  • [1] J.B. Taylor, Rev. Mod. Phys. 58, 741 (1986).
  • [2] T.R. Jarboe, Phys. Plasmas 12, 058103 (2005).
  • [3] H.A.B. Bodin and A.A. Newton, Nucl. Fusion 20, 1225 (1980).
  • [4] S.O. Knox et al., Phys. Rev. Lett. 56, 842 (1986).
  • [5] M. Nagata et al., Phys. Rev. Lett. 71, 4342 (1993).
  • [6] M. Nagata et al., Proceedings of 22nd IAEA Fusion Energy Conference (October 13-18, 2008, Geneva) EX/P6-7.
  • [7] M. Nagata et al., Phys. Plasmas 10, 2932 (2003).
  • [8] Y. Kagei et al., J. Plasma Fusion Res. 79, 217 (2003).
  • [9] T. Kanki et al., J. Plasma Fusion Res. SERIES 8, 1167 (2009).
  • [10] P.M. Bellan, Fundamentals of Plasma Physics (Cambridge University Press, Cambridge, 2006) p.382.
  • [11] R. Duck et al., Plasma Phys. Control. Fusion 39, 715 (1997).
  • [12] K.J. McCollam and T.R. Jarboe, Plasma Phys. Control. Fusion 44, 493 (2002).
  • [13] M. Nagata et al., Plasma and Fusion Res. 2, 035 (2007).

This paper may be cited as follows:

Takashi KANKI, Masayoshi NAGATA and Yasuhiro KAGEI, Plasma Fusion Res. 5, S2055 (2010).