Density Clamping and Power Deposition Profile in Rf Heated Plasma in Toroidal Helical Systems

Kimitaka Itoh, Sanae Itoh, Atsushi Fukuyama

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Radial transport driven by rf heating in toroidal helical systems with the large helical ripple is studied. The cyclotron resonance heating changes the pitch angle of resonating particles, so that the transition from the transit orbit to the trapped one occurs. The deviation of the average minor radius of the particle orbit from the magnetic surface strongly depends on the pitch angle of the particle velocity. Owing to this dependence, the slight change in the pitch angle by heating can generate a large step in the radial location. The approximate forms of the driven radial flow, which is rf-power-dependent, and the deformation of the heating profile are obtained. It is found that the deposition profile in this configuration is hardly made sharper than a critical gradient length. The injection of the heating power from the inside of the torus is preferable to improve the heating efficiency and to overcome the density clamping.

Original languageEnglish
Pages (from-to)482-488
Number of pages7
Journaljournal of the physical society of japan
Volume58
Issue number2
DOIs
Publication statusPublished - Jan 1 1989

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heating
pitch (inclination)
profiles
orbits
radial flow
transit
cyclotron resonance
ripples
injection
deviation
gradients
radii
configurations

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cite this

Density Clamping and Power Deposition Profile in Rf Heated Plasma in Toroidal Helical Systems. / Itoh, Kimitaka; Itoh, Sanae; Fukuyama, Atsushi.

In: journal of the physical society of japan, Vol. 58, No. 2, 01.01.1989, p. 482-488.

Research output: Contribution to journalArticle

Itoh, Kimitaka ; Itoh, Sanae ; Fukuyama, Atsushi. / Density Clamping and Power Deposition Profile in Rf Heated Plasma in Toroidal Helical Systems. In: journal of the physical society of japan. 1989 ; Vol. 58, No. 2. pp. 482-488.
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