Plasma and Fusion Research

Volume 3, 001 (2008)

Rapid Communications

On Fractal Properties of Equipotentials over a Real Rough Surface Faced to Plasma in Fusion Devices
Viacheslav Petrovich BUDAEV1,2) and Mikhail YAKOVLEV2)
1)
Nuclear Fusion Institute, RRC Kurchatov Institute, 123182, Kurchatov Sq.1, Moscow, Russia
2)
National Institute for Fusion Science, Oroshi 322-6, Toki, Gifu 509-5292, Japan
(Received 24 October 2007 / Accepted 16 November 2007 / Published 10 January 2008)

Abstract

We consider a sheath region bounded by a corrugated surface of material conductor and a flat boundary held to a constant voltage bias. The real profile of the film deposited from plasma on a limiter in a fusion device was used in numerical solving of the Poisson's equation to find a profile of electrostatic potential. The rough surface influences the equipotential lines over the surface. We characterized a shape of equipotential lines by a fractal dimension. The long-range correlation in the potential field is imposed by the non-trivial fractal structure of the surface. Dust particles bounced in such irregular potential field can accelerate due to the Fermi acceleration.

Keywords

plasma-surface interaction, sheath layer, dust motion, fractal boundary, deposited film, fusion device, Fermi acceleration

DOI: 10.1585/pfr.3.001

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References

  • [1] V.P. Budaev, Physica A 382, 359 (2007).
  • [2] S. Krasheninnikov et al., Phys. Plasmas 11, 3141 (2004).
  • [3] C.J.G. Evertszt and B. Mandelbrot, J. Phys. A Math. Gen. 21, 1781 (1992).
  • [4] B. Sapoval, Phys. Rev. Lett. 73, 3314 (1994).
  • [5] H. de O. Dias Filho et al., Physica A 342, 388 (2004).
  • [6] M. Lieberman and A. Lichtenberg, Principles of plasma discharges and materials processing (John Wiley & Sons, New York, 1994).
  • [7] O.C. Zienkiewicz and R.L. Taylor, The Finite Element Method, Vol. 1 - 3 (Butterworth-Heinemann, Oxford, 2000).
  • [8] Partial Differential Equation Toolbox User's Guide: For Use with MATLAB (The MathWorks, Inc., 1997).
  • [9] A. Loskutov and A. Ryabov, J. Stat. Phys. 108, 995 (2002).

This paper may be cited as follows:

Viacheslav Petrovich BUDAEV and Mikhail YAKOVLEV, Plasma Fusion Res. 3, 001 (2008).