Global approach to the spectral problem of microinstabilities in tokamak plasmas using a gyrokinetic model
Global approach to the spectral problem of microinstabilities in tokamak plasmas using a gyrokinetic model
复制标题
使用回旋模型解决托卡马克等离子体微观不稳定性光谱问题的全局方法
DOI：
10.1063/1.873113
复制
发表时间：
1998
影响因子：
2.2
通讯作者：
J. Václavík
中科院分区：
文献类型：
--
作者：
S. Brunner;M. Fivaz;T. Tran;J. Václavík
本文在回旋动力学理论的框架下，给出了托卡马克等离子体中静电微不稳定性的全二维本征值问题的一种解法。该方法是以前为圆柱系统开发的方法的推广[S. Brunner和J.Vaclavik，Phys.Plasmas 5，365（1998）]。通过在一个特殊的傅立叶空间中求解谱问题，轨道宽度和拉莫尔半径可以保持在所有的阶数。对于第一个数值实现，被认为是一个大的纵横比等离子体与圆形同心磁表面。基于高阶奈奎斯特法的特征频率识别算法，可以在并行计算机上直接实现。离子温度梯度相关的不稳定性的说明性结果。其中包括径向宽度的标度研究，和超环面和磁剪切扫描，以及非绝热捕获电子动力学的影响。
A solution to the full two-dimensional eigenvalue problem of electrostatic microinstabilities in a tokamak plasma is presented in the framework of gyrokinetic theory. The approach is the generalization of methods previously developed for a cylindrical system [S. Brunner and J. Vaclavik, Phys. Plasmas 5, 365 (1998)]. By solving the spectral problem in a special Fourier space adapted to the curved geometry, orbit width as well as Larmor radius can be kept to all orders. For a first numerical implementation, a large aspect ratio plasma with circular concentric magnetic surfaces is considered. A root finding algorithm for identifying the eigenfrequencies, based on a higher order Nyquist method, enables straightforward implementation on a parallel computer. Illustrative results for ion temperature gradient-related instabilities are presented. These include scaling studies of the radial width, and toroidicity and magnetic shear scans, as well as the effects of nonadiabatic trapped electron dynamics.