Abstract A novel kinetic-fluid hybrid model is developed for electromagnetic plasma turbulence in tokamak geometry. In this model, by combining kinetic and fluid approaches, ions are treated with the conventional gyrokinetic particle-in-cell method, while the bounce averaged drift-kinetic method is used for trapped electrons, and passing electrons are modeled as a massless fluid to avoid numerical instabilities due to fast parallel motions of electrons. The new model is implemented in a global gyrokinetic code gKPSP (Kwon et al., 2012). In benchmark tests for linear electromagnetic instabilities, this model shows good agreement with the global gyrokinetic codes GENE and GTC. By combining kinetic and fluid approaches, it is demonstrated that electromagnetic simulations can be reliably performed with only a modest increase of numerical costs. The new model is employed to study the effects of plasma elongation on kinetic ballooning mode (KBM). It is found that the elongation has a stabilizing effect on KBM, which is consistent with the broadened parallel wave number spectrum of KBM instabilities.

中文翻译：

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一种新的托卡马克等离子体湍流混合仿真模型

摘要 针对托卡马克几何中的电磁等离子体湍流开发了一种新的动力学-流体混合模型。在该模型中，通过结合动力学和流体方法，离子用传统的陀螺动力学粒子在细胞内方法处理，而反弹平均漂移动力学方法用于捕获电子，通过的电子被建模为无质量流体，以避免由于电子的快速平行运动引起的数值不稳定性。新模型在全球陀螺动力学代码 gKPSP 中实现（Kwon 等，2012）。在线性电磁不稳定性的基准测试中，该模型与全球陀螺运动代码 GENE 和 GTC 显示出良好的一致性。通过结合动力学和流体方法，证明只需适度增加数值成本就可以可靠地执行电磁模拟。新模型用于研究等离子体伸长对动力学气球模态 (KBM) 的影响。发现伸长率对KBM具有稳定作用，这与KBM不稳定性的加宽平行波数谱一致。