ExB shear and precession shear induced turbulence suppression and its influence on electron thermal internal transport barrier formation

E × B shear and trapped electron precession shear induced suppression of micro-turbulence is studied in general tokamak geometry. A systematic derivation of a two-point equation for trapped electron related turbulence based on modern bounce kinetic formalism is performed. A two-point nonlinear analy...

Full description

Saved in:
Bibliographic Details
Published in:Physics of plasmas 2016-07, Vol.23 (7)
Main Authors: Choi, G. J., Hahm, T. S.
Format: Article
Language:English
Subjects:
Electrons
Nonlinear analysis
Plasma physics
Plasmas (physics)
Precession
Shear
Shearing
Tokamak devices
Transport
Turbulence
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:E × B shear and trapped electron precession shear induced suppression of micro-turbulence is studied in general tokamak geometry. A systematic derivation of a two-point equation for trapped electron related turbulence based on modern bounce kinetic formalism is performed. A two-point nonlinear analysis yields the new criterion for the turbulence suppression | ω E × B + ω PS | > Δ ω T , where Δ ω T is decorrelation rate of the ambient turbulence, ω E × B is E × B shearing rate in general tokamak geometry [Hahm and Burrell, Phys. Plasmas 2, 1648 (1995)], and ω PS is precession shearing rate. Therefore, both E × B shear and trapped electron precession shear can contribute to suppression of turbulence, and these effects can either add up or subtract depending on their relative sign. This result provides a better understanding of electron thermal internal transport barrier formation under various conditions.
ISSN:1070-664X
1089-7674
DOI:10.1063/1.4954910