Computing nonlinear magnetohydrodynamic edge localized instabilities in fusion plasmas
Computing nonlinear magnetohydrodynamic edge localized instabilities in fusion plasmas
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DOI：
10.1088/1742-6596/46/1/009
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发表时间：
2006-09
期刊：
影响因子：
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通讯作者：
D. Brennan;S. Kruger;D. Schnack;C. Sovinec;A. Pankin
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文献类型：
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作者：
D. Brennan;S. Kruger;D. Schnack;C. Sovinec;A. Pankin
环形约束等离子体中的边缘局域模（ELMs）的发生和非线性演化已知从约束区域的边缘流出热能，并且还可以通过非线性模式耦合影响核心等离子体。这一过程的物理学还没有得到很好的理解，尽管伴随的热能传输的大爆发是未来燃烧等离子体实验的主要关注点。ELMs的演变本质上是非线性的，分析方法受到问题复杂性的限制。除了少数最近的重要理论工作，ELMs的非线性后果主要是未开发的。尼姆罗德代码[http://nimrodteam.org]的最新发展使得在扩展磁流体动力学（MHD）框架中对托克马克中的ELM进行计算研究成为可能，并且形成了一项新的举措来了解其非线性演化的基本物理学。这些调查的结果，提出了两个模型的平衡和准确的重建从DIII-D实验在通用原子[http：//fusion.gat.com/dii-d/]。这些结果表明，一个附加的高温结构径向向外传播，这是强烈阻尼实验相关的环向流剪切。两个流体和陀螺粘性条款包括线性作为这些重要的物理效应的初步指示，并观察到更高的波数模式的稳定。
The onset and nonlinear evolution of Edge Localized Modes (ELMs) in toroidally confined plasmas are known to shed thermal energy from the edge of the confinement region, and may also affect the core plasma through nonlinear mode coupling. The physics of this process is not well understood, although the concomitant large bursts of thermal energy transport are a major concern for future burning plasma experiments. The evolution of ELMs is inherently nonlinear and analytic approaches are limited by the complexity of the problem. Save a handful of recent important theoretical works, the nonlinear consequences of ELMs are mainly unexplored. Recent developments in the NIMROD code [http://nimrodteam.org] have enabled the computational study of ELMs in tokamaks in the extended magnetohydrodynamic (MHD) framework, and a new initiative was formed to understand the basic physics of their nonlinear evolution. The results of these investigations are presented for both model equilibria and accurate reconstructions from the DIII-D experiment at General Atomics [http://fusion.gat.com/diii-d/]. These results show a filamentary high temperature structure propagating radially outward, which is strongly damped by experimentally relevant toroidal flow shear. Two fluid and gyroviscous terms are included linearly as a preliminary indication of these important physical effects, and stabilization of higher wave number modes is observed.