Effect of the externally driven velocity shear on the turbulence radial wavenumber spectral shift and its amplitude

被引：4

作者：

Xiao, G. L. ^{[1
,2
]}

Zou, X. L. ^{[3
]}

Zhong, W. L. ^{[1
]}

Song, S. D. ^{[1
]}

Liang, A. S. ^{[1
]}

Liu, A. D. ^{[4
,5
]}

Xu, M. ^{[1
]}

Duan, X. R. ^{[1
]}

机构：

[1] Southwestern Inst Phys, POB 432, Chengdu 610041, Sichuan, Peoples R China

[2] Tsinghua Univ, Dept Engn Phys, Beijing 100084, Peoples R China

[3] CEA, IRFM, F-13108 St Paul Les Durance, France

[4] Univ Sci & Technol China, KTX Lab, Hefei 230026, Anhui, Peoples R China

[5] Univ Sci & Technol China, Dept Modern Phys, Hefei 230026, Anhui, Peoples R China

来源：

PHYSICS OF PLASMAS | 2019年 / 26卷 / 07期

基金：

中国国家自然科学基金; 国家重点研发计划;

关键词：

EDGE-LOCALIZED MODES; DENSITY FLUCTUATIONS; POLOIDAL ROTATION; ZONAL FLOW; MAGNETIC SHEAR; TRANSPORT; BIFURCATION; CONFINEMENT; PLASMA; SUPPRESSION;

D O I：

10.1063/1.5095791

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

It has been observed that the plasma velocity shear can be strongly affected by external source input, such as neutral beam injection, lower hybrid current drive, supersonic molecule beam injection, and impurity injection. Such a change in velocity shear can lead to turbulence suppression or enhancement by inducing a spectral shift in the turbulence radial wavenumber spectrum. A theoretical model, based on the nonlinear evolution of the turbulence amplitude with an externally driven velocity shear, combined with the thermal transport equation, has been used to describe the turbulence evolution. A critical growth rate gamma(0) for the turbulence regulation has been identified in this theoretical model, and the parametric dependency of gamma(0) is investigated. A threshold U-c of the reduction value of the velocity shear rate U, intimately related to gamma(0), has been found for the triggering radial wavenumber shift. This indicates that the turbulence could be regulated by external source input, when U > U-c.

引用

页数：9