A novel plasma-wall instability and the distribution of halo currents in tokamaks

被引:11
作者
Caloutsis, A [1 ]
Gimblett, CG [1 ]
机构
[1] UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon, Oxon, England
关键词
D O I
10.1088/0029-5515/38/10/306
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 is recognized that tokamak plasma disruptions and vertical displacement events, with the attendant appearance of 'halo currents', are a threat to future experiments such as ITER. Halo currents, flowing between the plasma and the wall, can develop large spatially localized components. Here, this is ascribed to a new instability that can occur in a composite circuit of a magnetized plasma and a solid conductor. The presence of the conductor divides the current perturbation into topologically distinct stable and unstable composite plasma-wall circuits. The plasma paths of such circuits are subject to hydromagnetic motions, which alter circuit geometry and conductivity while self-consistently preserving toroidal and poloidal periodicity. A simple prototype model is developed that is solved numerically and analytically to illustrate the geometrical aspect of the mechanism. The heterogeneity of the true plasma-wall system is shown to introduce considerable complexity. The basic concept may underlie a wider class of instabilities and waves.
引用
收藏
页码:1487 / 1499
页数:13
相关论文
共 12 条
[1]   A TIME-DEPENDENT MODEL FOR RAILGUN PLASMA ARMATURES [J].
BATTEH, JH ;
ROLADER, GE ;
POWELL, JD ;
DESAI, PV .
PHYSICS OF FLUIDS, 1988, 31 (06) :1757-1765
[2]  
CASTLE GG, 1996, CONTROLLED FUSIO C 1, V20, P420
[3]   Measurements of non-axisymmetric halo currents with and without 'killer' pellets during disruptions in the DIII-D tokamak [J].
Evans, TE ;
Kellman, AG ;
Humphreys, DA ;
Schaffer, MJ ;
Taylor, PL ;
Whyte, DG ;
Jernigan, TC ;
Hyatt, AW ;
Lee, RL .
JOURNAL OF NUCLEAR MATERIALS, 1997, 241 :606-611
[4]   Disruptions and halo currents in Alcator C-Mod [J].
Granetz, RS ;
Hutchinson, IH ;
Sorci, J ;
Irby, JH ;
LaBombard, B ;
Gwinn, D .
NUCLEAR FUSION, 1996, 36 (05) :545-556
[5]   VERTICAL DISPLACEMENT EVENTS AND HALO CURRENTS [J].
GRUBER, O ;
LACKNER, K ;
PAUTASSO, G ;
SEIDEL, U ;
STREIBL, B .
PLASMA PHYSICS AND CONTROLLED FUSION, 1993, 35 :B191-B204
[6]  
MOROZOV AI, 1996, REV PLASMA PHYSICS, V2, P32
[7]   Effect of halo current and its toroidal asymmetry during disruptions in JT-60U [J].
Neyatani, Y ;
Yoshino, R ;
Ando, T .
FUSION TECHNOLOGY, 1995, 28 (04) :1634-1643
[8]  
NOLL P, 1996, FUSION TECHNOL, P73
[9]  
ORTOLANI S, 1995, CONTROLLED FUSION PL, V19, P9
[10]  
Taylor P.L., 1995, DIII-D disruption studies