Return To: Session TH3 - Theory 3 (Saturday, 24 October)
Prev Page: Session TH3 - Theory 3 (Saturday, 24 October)
Next Page: (TH3/2) Influence of the Plasma Edge on Tokamak

(TH3/1) Dynamics of Zonal Flows and Self-Regulating Drift-Wave Turbulence

   
P. H. Diamond ¹, M. Rosenbluth ², F. L. Hinton ³, M. Malkov ⁴, J. Fleischer ¹, A. Smolyakov ^5
 
1 University of California at San Diego, La Jolla, CA 92093-0319 USA
² ITER San Diego Joint Work Site, La Jolla, CA 92037 USA
³ General Atomics, San Diego, CA 92138-5608 USA
⁴ Max Planck Institute for Nuclear Physics, Heidelberg, 69029 Germany
⁵ University Of Saskatchewan, Saskatchewan, S7N 0W0 Canada

Abstract
We present a theory of zonal flow  - drift wave dynamics . Zonal flows are generated by modulational instability of a drift wave spectrum, and are damped by collisions. Drift waves undergo random shearing-induced refraction, resulting in increased mean square radial wavenumber. Drift waves and zonal flows together form a simple dynamical system, which has a single stable fixed point. In this state, the fluctuation intensity and turbulent diffusivity are ultimately proportional to the collisional zonal flow damping. The implications of these results for transport models is discussed.

Read the full paper in PDF format.