Internal kink (IK) instability is investigated for European demonstration fusion reactor (EU DEMO) plasmas in both negative triangularity (NT) and positive triangularity (PT) configurations. For NT plasmas, the IK becomes more unstable as an ideal conformal wall moves away from the plasma boundary, with the mode growth rate saturating at the wall radial location of about , where a is the plasma minor radius and b the wall radial location. The plasma resistivity destabilizes the IK mode. The effect of sub-sonic toroidal plasma flow is sufficiently weak and can thus be ignored for these EU DEMO equilibria. These results are consistent with those for PT plasmas, albeit with larger mode growth rate in the NT configuration. Both perturbative and self-consistent magneto-hydrodynamic (MHD)-kinetic hybrid calculations predict (partial) stabilization of the IK modes in both NT and PT configurations, with inclusion of various kinetic contributions. Precessional drift motion of trapped fusion-born alphas in EU DEMO produces weak stabilization to the IK mode. Stronger stabilization occurs with the toroidal precession of trapped thermal particles (ions and electrons) and the bounce-transit motion of thermal ions. The stabilization is similar between the NT and PT configurations, due to the similarity of the mode eigenfunction (occupying a nearly circular region in the plasma core) despite the sign difference in the triangularity. The non-perturbative MHD-kinetic hybrid model predicts much less stabilization of the mode than the perturbative model, primarily due to the self-consistent determination of the mode eigenvalue in the former. Generally, no significant difference in the IK mode stability is found between the NT and PT plasmas in EU DEMO.

研究了负三角 (NT) 和正三角 (PT) 配置的欧洲示范聚变反应堆 (EU DEMO) 等离子体的内部扭结 (IK) 不稳定性。对于 NT 等离子体，当理想的共形壁远离等离子体边界时，IK 变得更加不稳定，模式生长速率在壁径向位置饱和约，其中a是等离子体短半径，b墙径向位置。等离子体电阻率使 IK 模式不稳定。亚音速环形等离子体流的影响非常弱，因此对于这些 EU DEMO 平衡可以忽略不计。这些结果与 PT 等离子体的结果一致，尽管在 NT 配置中具有更大的模式增长率。微扰和自洽磁流体动力学 (MHD) 动力学混合计算均预测 NT 和 PT 配置中 IK 模式的（部分）稳定性，包括各种动力学贡献。EU DEMO 中被困融合产生的 alpha 的岁差漂移运动对 IK 模式产生弱稳定性。捕获的热粒子（离子和电子）的环形进动和热离子的反弹跃迁运动会产生更强的稳定性。NT 和 PT 配置之间的稳定性是相似的，这是由于模式特征函数的相似性（在等离子体核心中占据近乎圆形的区域），尽管三角形的符号不同。与微扰模型相比，非微扰 MHD 动力学混合模型预测的模式稳定性要低得多，这主要是由于前者的模式特征值的自洽确定。通常，在 EU DEMO 中，NT 和 PT 等离子体之间没有发现 IK 模式稳定性的显着差异。主要是由于前者的模式特征值的自洽确定。通常，在 EU DEMO 中，NT 和 PT 等离子体之间没有发现 IK 模式稳定性的显着差异。主要是由于前者的模式特征值的自洽确定。通常，在 EU DEMO 中，NT 和 PT 等离子体之间没有发现 IK 模式稳定性的显着差异。