Kim, E. and Anderson, J. (2009) Statistical theory of plasma turbulence. Plasma and Fusion Research, 4. Art no. 030. ISSN 1880-6821
Abstract
We present a statistical theory of intermittency in plasma turbulence based on short-lived coherent structures (instantons). In general, the probability density functions (PDFs) of the flux R are shown to have an exponential scaling P(R) ∝ exp (-cRs ) in the tails. In ion-temperature-gradient turbulence, the exponent takes the value s = 3/2 for momentum flux and s = 3 for zonal flow formation. The value of s follows from the order of the highest nonlinear interaction term and the moments for which the PDFs are computed. The constant c depends on the spatial profile of the coherent structure and other physical parameters in the model. Our theory provides a powerful mechanism for ubiquitous exponential scalings of PDFs, often observed in various tokamaks. Implications of the results, in particular, on structure formation are further discussed.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2009 the Japan Society of Plasma Science and Nuclear Fusion Research. Reproduced in accordance with the publisher's self-archiving policy. |
Keywords: | turbulence; structure; shear flow; confinement; probability density function (PDF) |
Dates: |
|
Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > School of Mathematics and Statistics (Sheffield) |
Depositing User: | Mrs Megan Hobbs |
Date Deposited: | 29 Mar 2010 12:01 |
Last Modified: | 17 Nov 2015 17:47 |
Published Version: | http://dx.doi.org/10.1585/pfr.4.030 |
Status: | Published |
Publisher: | the Japan Society of Plasma Science and Nuclear Fusion Research |
Identification Number: | 10.1585/pfr.4.030 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:10501 |