[Table of Contents]

Plasma and Fusion Research

Volume 2, S1087 (2007)

Regular Articles

The Neutral Transport Analysis Based on Visible Light Measurement of Recycling and 3-Dimensional Simulation in GAMMA 10
Yuta HIGASHIZONO, Yousuke NAKASHIMA, Mamoru SHOJI1), Shinji KOBAYASHI2), Nobuhiro NISHINO3), Hirokazu KAWANO, Yuusuke KUBOTA, Takayuki KOBAYASHI, Masayuki YOSHIKAWA, Yoshiyuki MISHIMA, Mirai SUZUKI, Keiji MORI and Teruji CHO
Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
1)
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
2)
Institute of Advanced Energy, Kyoto University, Gokasho, Uji 611-0011, Japan
3)
Graduate School of Engineering, Hiroshima University, Hiroshima 739-8527, Japan
(Received 5 December 2006 / Accepted 2 April 2007 / Published 20 November 2007)

Abstract

Neutral transport related to recycling phenomena on two limiters installed in the central-cell was studied in the GAMMA 10 tandem mirror plasmas. Dependence of iris limiter is investigated in terms of plasma diamagnetism and Hα-line intensity. It was found that a plasma diamagnetic signal was improved and Hα-line intensity near the iris limiter increased if the diameter of the iris limiter shrank to 340 mm. Fully 3-dimensional Monte-Carlo simulation (DEGAS) was executed with the recycling source on the limiters. The neutral sources on the limiters were consistently given so as to satisfy 2-dimensional (2-d) image obtained by a high-speed camera. The determined Hα-line intensity from DEGAS well explained the experimental result. The simulation result, in the 340 mm case, predicted the reduction in the peak value of Hα-line intensity on the central limiter and the enhancement on the iris limiter. It suggests that the reduction of the recycling on the central limiter makes it possible to lead the better plasma performance.

Keywords

GAMMA 10, tandem mirror, neutral transport, Monte-Carlo simulation, DEGAS, limiter, hydrogen recycling, Hα-line intensity, 2-d image

DOI: 10.1585/pfr.2.S1087

Full Text

PDF format (685Kbytes) PDF Download

References

  • [1] T. Nakashima et al., J. Nucl. Mater. 196-198, 493 (1992).
  • [2] S. Kobayashi et al., J. Nucl. Mater. 266-269, 566 (1999).
  • [3] T. Cho et al., Nucl. Fusion 45, 1650 (2005).
  • [4] Y. Higashizono et al., Trans. Fusion Technol. 47 No.1T, 297 (2005).
  • [5] N. Nishino et al., Plasma Fusion. Res. 1, 035 (2006).
  • [6] D.B. Heifetz et al., J. Comp. Phys. 46, 309 (1982).
  • [7] D.P. Stotler et al., Phys. Plasmas. 3, 4084 (1996).
  • [8] M. Inutake et al., Phys. Rev. Lett. 55, 939 (1985).
  • [9] Y. Nakashima et al., J. Nucl. Mater. 313-316, 553 (2003).

This paper may be cited as follows:

Yuta HIGASHIZONO, Yousuke NAKASHIMA, Mamoru SHOJI, Shinji KOBAYASHI, Nobuhiro NISHINO, Hirokazu KAWANO, Yuusuke KUBOTA, Takayuki KOBAYASHI, Masayuki YOSHIKAWA, Yoshiyuki MISHIMA, Mirai SUZUKI, Keiji MORI and Teruji CHO, Plasma Fusion Res. 2, S1087 (2007).