Interplay between turbulence, neoclassical and zonal flows during the transition from low to high confinement mode at ASDEX Upgrade

被引：40

作者：

Cavedon, M. ^{[1
,2
]}

Puetterich, T. ^{[1
]}

Viezzer, E. ^{[1
]}

Birkenmeier, G. ^{[1
,2
]}

Happel, T. ^{[1
]}

Laggner, F. M. ^{[3
]}

Manz, P. ^{[1
,2
]}

Ryter, F. ^{[1
]}

Stroth, U. ^{[1
,2
]}

机构：

[1] Max Plank Inst Plasmaphys, D-85748 Garching, Germany

[2] Tech Univ Munich, Phys Dept E28, D-85748 Garching, Germany

[3] TU Wien, Inst Appl Phys, Fus OAW, A-1040 Vienna, Austria

来源：

NUCLEAR FUSION | 2017年 / 57卷 / 01期

关键词：

L-H transition; neoclassical flow; turbulence flow interaction; EDGE TURBULENCE; H TRANSITION; TRANSPORT; TOKAMAK; PLASMA;

D O I：

10.1088/0029-5515/57/1/014002

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：

The spatio-temporal interplay between turbulence, mean and zonal flows has been investigated at the L-H and H-L transitions in the edge region of the ASDEX Upgrade tokamak. Close to both transitions, an intermediate phase (I-phase) characterized by 'limit cycle like oscillations' (LCOs) is observed in which periodic bursts of turbulence correlate with ExB flow reduction and relaxation of gradients. During the I-phase, the ExB velocity is dominated by the mean flows indicating that turbulence driven flows are small. Periodic dithers between L-mode and the phases with LCOs are also observed just before the H-mode onset where the edge density and temperature profile gradients evolve on similar timescale as the flows. Thus connection between mean and ExB flows holds during the all evolution from L-mode to H-mode demonstrating the fundamental role of the neoclassical flows in the L-H transition physics.

引用

页数：6

共 29 条

[1] INFLUENCE OF SHEARED POLOIDAL ROTATION ON EDGE TURBULENCE [J].

BIGLARI, H ;

DIAMOND, PH ;

TERRY, PW .

PHYSICS OF FLUIDS B-PLASMA PHYSICS, 1990, 2 (01) :1-4

[2] Dynamics of Low-Intermediate-High-Confinement Transitions in Toroidal Plasmas [J].

Cheng, J. ;

Dong, J. Q. ;

Itoh, K. ;

Yan, L. W. ;

Xu, M. ;

Zhao, K. J. ;

Hong, W. Y. ;

Huang, Z. H. ;

Ji, X. Q. ;

Zhong, W. L. ;

Yu, D. L. ;

Itoh, S. -I. ;

Nie, L. ;

Kong, D. F. ;

Lan, T. ;

Liu, A. D. ;

Zou, X. L. ;

Yang, Q. W. ;

Ding, X. T. ;

Duan, X. R. ;

Liu, Yong .

PHYSICAL REVIEW LETTERS, 2013, 110 (26)

[3] Slow L-H transitions in DIII-D plasmas -: art. no. 255002 [J].

Colchin, RJ ;

Schaffer, MJ ;

Carreras, BA ;

McKee, GR ;

Maingi, R ;

Carlstrom, TN ;

Rudakov, DL ;

Greenfield, CM ;

Rhodes, TL ;

Doyle, EJ ;

Brooks, NH ;

Austin, ME .

PHYSICAL REVIEW LETTERS, 2002, 88 (25) :255002-255002

[4] Mean and Oscillating Plasma Flows and Turbulence Interactions across the L-H Confinement Transition [J].

Conway, G. D. ;

Angioni, C. ;

Ryter, F. ;

Sauter, P. ;

Vicente, J. .

PHYSICAL REVIEW LETTERS, 2011, 106 (06)

[5] Zonal flows in plasma - a review [J].

Diamond, PH ;

Itoh, SI ;

Itoh, K ;

Hahm, TS .

PLASMA PHYSICS AND CONTROLLED FUSION, 2005, 47 (05) :R35-R161

[6] SELF-REGULATING SHEAR-FLOW TURBULENCE - A PARADIGM FOR THE L TO H TRANSITION [J].

DIAMOND, PH ;

LIANG, YM ;

CARRERAS, BA ;

TERRY, PW .

PHYSICAL REVIEW LETTERS, 1994, 72 (16) :2565-2568

[7] Spatiotemporal Structure of the Interaction between Turbulence and Flows at the L-H Transition in a Toroidal Plasma [J].

Estrada, T. ;

Hidalgo, C. ;

Happel, T. ;

Diamond, P. H. .

PHYSICAL REVIEW LETTERS, 2011, 107 (24)

[8] Probabilistic lithium beam data analysis [J].

Fischer, R. ;

Wolfrum, E. ;

Schweinzer, J. .

PLASMA PHYSICS AND CONTROLLED FUSION, 2008, 50 (08)

[9]

Happel T., 2013, P 11 INT REFL WORKSH

[10] THEORY OF PLASMA TRANSPORT IN TOROIDAL CONFINEMENT SYSTEMS [J].

HINTON, FL ;

HAZELTINE, RD .

REVIEWS OF MODERN PHYSICS, 1976, 48 (02) :239-308

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