论文标题
扰动轴对称磁平衡以获得准轴对称恒星
Perturbing an axisymmetric magnetic equilibrium to obtain a quasi-axisymmetric stellarator
论文作者
论文摘要
证明可以通过给定的轴对称平衡的扰动直接构建有限压力，大约准轴对称恒星平衡（无数值优化）。这种扰动的大小是通过分数外旋的两种方式测量的，或者通过相对磁场强度，即扰动磁场的平均大小除以未渗透的场强度。发现明显的分数外部旋转变换可以通过准轴对称扰动产生，尽管前者的尺寸更弱，但相对场强的值的相对场强度具有相似的相对场强度。高模式数字扰动被确定为使用本地电流分布生成这种转换的候选者。讨论了对一般非扰动求解器发展对最佳恒星平衡的影响。
It is demonstrated that finite-pressure, approximately quasi-axisymmetric stellarator equilibria can be directly constructed (without numerical optimization) via perturbations of given axisymmetric equilibria. The size of such perturbations is measured in two ways, via the fractional external rotation and, alternatively, via the relative magnetic field strength, i.e. the average size of the perturbed magnetic field, divided by the unperturbed field strength. It is found that significant fractional external rotational transform can be generated by quasi-axisymmetric perturbations, with a similar value of the relative field strength, despite the fact that the former scales more weakly with the perturbation size. High mode number perturbations are identified as a candidate for generating such transform with local current distributions. Implications for the development of a general non-perturbative solver for optimal stellarator equilibria is discussed.
