Nonlinear equilibria, stability and generation of zonal structures in toroidal plasmas

L. Chen, F. Zonca

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

The long-lived saturated zonal flow (ZF) structures, spontaneously generated by drift-wave (DW) turbulence, are viewed as generators of nonlinear equilibria. Here, we derive a nonlinear evolution equation for the zonal response, valid for arbitrary wavelengths, whose time-asymptotic behaviour corresponds to the nonlinear equilibrium. Its corresponding stability, meanwhile, determines the nature of the ZF instability and the nonlinear up-shift of turbulent transport thresholds. On a shorter-time scale, the temporal evolution of the zonal response describes the DW-ZF generation and the regulation of the DW intensity by the ZFs. As an application, we present a kinetic stability analysis of zonal structures in the ion temperature gradient driven DW turbulence case as well as the corresponding collisionless zonal dissipation rates. © 2007 IAEA.
Original languageEnglish
Article number021
Pages (from-to)886 - 891
Number of pages6
JournalNuclear Fusion
Volume47
Issue number8
DOIs
Publication statusPublished - 1 Aug 2007
Externally publishedYes

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All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)
  • Condensed Matter Physics
  • Nuclear and High Energy Physics

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