The stabilizing effect of flow shear on m/n=3/2 magnetic island width in DIII-D
The stabilizing effect of flow shear on m/n=3/2 magnetic island width in DIII-D
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DOI：
10.1063/1.3077673
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发表时间：
2008-11
影响因子：
2.2
通讯作者：
R. L. Haye;R. Buttery
中科院分区：
文献类型：
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作者：
R. L. Haye;R. Buttery
在DIII-D模型中发现，流动剪切通过一个更负的经典撕裂稳定性指数Δ′对m/n=3/2的新经典撕裂模岛有稳定作用[J. L. Luxon，Nucl. Fusion 42，614（2002）]托卡马克。加热中性束在同向和反向之间混合，以改变等离子体上的扭矩，从而改变等离子体流（旋转）和流剪切。这是在饱和的m/n=3/2新古典撕裂模式（NTM）的存在下进行的“一枪一枪”，同时缓慢地将等离子体β升高到m/n=2/1模式开始的极限。本文提出了一个关于流动剪切对Δ′的稳定作用的启发式模型，用以解释流动剪切如何减小NTM岛的尺寸，以及如何消除较高β和伴随的螺旋扰动自举电流的不稳定作用。
It is found that flow shear has a stabilizing effect on m/n=3/2 neoclassical tearing mode islands through a more negative classical tearing stability index Δ′ in the DIII-D [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] tokamak. The heating neutral beams are mixed between co- and counter-directions to vary the torque on the plasma and thus the plasma flow (rotation) and flow shear. This is done “shot to shot” in the presence of a saturated m/n=3/2 neoclassical tearing mode (NTM) while slowly raising the plasma beta up to the limit of the onset of an m/n=2/1 mode. A heuristic model for the stabilizing effect of flow shear on Δ′ is shown to explain how flow shear acts to reduce NTM island size and obviate the effect of higher beta and concomitant destabilizing helically perturbed bootstrap current.