Plasma and Fusion Research

Volume 13, 3402078 (2018)

Regular Articles

Topological Transition and Inductive Current Drive of a Translated Field-Reversed Configuration Plasma
Mamiko ARAI, Tomohiko ASAI, Seri KATAYAMA, Junpei ISHIWATA, Naoto ONO, Junichi SEKIGUCHI, Tsutomu TAKAHASHI, Michiaki INOMOTO1), Toshiki TAKAHASHI2), Shigefumi OKADA3), Yoshiro NARUSHIMA4) and Loren C. STEINHAUER5)
College of Science and Technology, Nihon University, Tokyo 101-8308, Japan
1)
Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8561, Japan
2)
Graduate School of Engineering, Gunma University, Gunma 376-0052, Japan
3)
Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan
4)
National Institute for Fusion Science, Gifu 509-5292, Japan
5)
TAE Technologies, Inc., 19631 Pauling, Foothill Ranch, CA 92610, USA
(Received 28 December 2017 / Accepted 2 April 2018 / Published 25 June 2018)

Abstract

A field-reversed configuration (FRC) is a high-beta compact toroid, ideally with an exclusive poloidal magnetic field. As an FRC has a simply-connected geometry, it can be translated along an external guide magnetic field and trapped in a confinement region with a quasi-static external magnetic field. In the FAT (FRC amplification via translation)-ICD (inductive current drive) experiment, a center solenoid is installed in a quasi-spherical confinement region to create an inductive toroidal current drive. An FRC formed by a field-reversed theta-pinch is translated at a velocity of 100 - 200 km/s into a confinement region comprising a center structure. Such an FRC then changes from a simply-connected structure to a torus. The magnetic field structures of FRCs have been directly observed using an internal magnetic probe array installed at the mid-plane of the confinement region. We observed that an FRC can be translated successfully without any disruptive perturbation to its structure and that the magnetic flux can be quadrupled via the inductive current drive, as compared with the cases without an inductive current drive. Herein, we report in detail the evidence for the inductive drive and relaxation process of the translated FRC.

Keywords

field-reversed configuration, center solenoid, inductive current drive, field-reversed theta-pinch

DOI: 10.1585/pfr.13.3402078

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References

  • [1] M. Tuszewski, Nucl. Fusion 28, 2033 (1988).
  • [2] Ts. Takahashi and Y. Hirano, J. Plasma Fusion Res. 84, 507 (2008).
  • [3] M. Tuszewski and B.L. Wright, Phys. Rev. Lett. 63, 2236 (1989).
  • [4] A. Shiokawa and S. Goto, Phys. Fluids B 5, 534 (1993).
  • [5] H.Y. Guo, A.L. Hoffman, L.C. Steinhauer and K.E. Miller, Phys. Rev. Lett. 95, 175001 (2005).
  • [6] J. Sekiguchi, T. Asai and Ts. Takahashi, Rev. Sci. Instrum. 89, 013506 (2017).
  • [7] Y. Ono, T. Akao, M. Katsurai and M. Yamada, Phys. Fluids B 5, 3691 (1993).
  • [8] S.P. Gerhardt, E. Belova, M. Inomoto et al., Phys. Plasmas 13, 112508 (2006).