The suppression of runaway electrons (REs) is influenced by the size of pre-existing 2/1 magnetic islands. Simulations of argon (Ar) massive gas injection into J-TEXT plasmas with pre-existing 2/1 magnetic islands of different width are performed with the 3D magnetohydrodynamic code called NIMROD (Sovinec et al 2004 J. Comput. Phys. 195 355). Results show that the ratio of remaining REs is not monotonically dependent on the width of pre-existing 2/1 magnetic islands. Large enough pre-existing 2/1 magnetic islands can lead to strong magnetic perturbation and strong magnetic surface stochasticity to expel the REs. The critical width for the suppression of REs is to be 0.31 as the minor radius. Under the condition of suitable small pre-existing 2/1 magnetic islands width, with island width ranging from 0.07 to 0.11 times the minor radius, the mitigation of REs is achieved. The duration of magnetic perturbations δB/B ( n = 1) (exceeding (4 to 6) × 10...

中文翻译：

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J-TEXT破坏模拟中2/1预先存在的磁岛宽度对抑制失控电子的影响

失控电子（REs）的抑制受预先存在的2/1磁岛的大小影响。使用称为NIMROD的3D磁流体动力学代码，对预先存在不同宽度的2/1磁性岛的J-TEXT等离子体中的氩气（Ar）大量气体注入进行了模拟（Sovinec等，2004 J. Comput。Phys。195 355）。结果表明，剩余稀土元素的比例不单调取决于现有2/1磁性岛的宽度。预先存在的足够大的2/1磁岛可能会导致强烈的磁扰动和强烈的磁性表面随机性，从而排出RE。抑制RE的临界宽度应为小半径0.31。在预先存在的2/1小磁岛宽度合适的情况下，磁岛宽度为小半径的0.07到0.11倍，减少了可再生能源。磁扰动的持续时间δB/ B（n = 1）（超过（4至6）×10 ...