论文标题
曲线正交坐标系统中的显式保护结构的几何粒子算法及其应用于Tokamak物理学的全部设备6D动力学模拟
Explicit Structure-Preserving Geometric Particle-in-Cell Algorithm in Curvilinear Orthogonal Coordinate Systems and Its Applications to Whole-Device 6D Kinetic Simulations of Tokamak Physics
论文作者
论文摘要
开发了曲线正交坐标系中的显式保护结构的几何粒子（PIC）算法。报道的工作代表了结构保存的几何图片算法的进一步发展[1-12]，实现了在磁融合研究中实现实际应用的目的。该算法是通过使用惠特尼形式，离散的外部计算和明确的非统计符号整合整合的带电颗粒和电磁场系统的田间理论来构建的。除了截短的无限尺寸符号结构外，该算法还保留了许多重要的物理对称性和保护定律，例如局部能量保护，仪表对称性和相应的局部电荷保护。结果，该算法具有基于第一原理的多尺度Tokamak物理学所需的长期准确性和保真度。该算法已在Sympic代码中实现，该算法是为现代簇中的高效平行PIC模拟而设计的。该代码已应用于对Tokamak物理学的全部设备6D动力学模拟研究。在数值上以对角线和各向异性压张量为主，在数值上发现了融合等离子体的融合等离子体的自洽动力学稳态。该州还接受了10 km/s范围内的稳态亚环离子流，同意实验观察结果[13，14]和分析计算[15，16]。模拟了在自洽动力学稳态中的动力动力不稳定。它表明，高N气球模式的增长率比低N全局模式更大，在非线性相中，模式在5个离子运输时间大约饱和...
Explicit structure-preserving geometric Particle-in-Cell (PIC) algorithm in curvilinear orthogonal coordinate systems is developed. The work reported represents a further development of the structure-preserving geometric PIC algorithm [1-12], achieving the goal of practical applications in magnetic fusion research. The algorithm is constructed by discretizing the field theory for the system of charged particles and electromagnetic field using Whitney forms, discrete exterior calculus, and explicit non-canonical symplectic integration. In addition to the truncated infinitely dimensional symplectic structure, the algorithm preserves exactly many important physical symmetries and conservation laws, such as local energy conservation, gauge symmetry and the corresponding local charge conservation. As a result, the algorithm possesses the long-term accuracy and fidelity required for first-principles-based simulations of the multiscale tokamak physics. The algorithm has been implemented in the SymPIC code, which is designed for high-efficiency massively-parallel PIC simulations in modern clusters. The code has been applied to carry out whole-device 6D kinetic simulation studies of tokamak physics. A self-consistent kinetic steady state for fusion plasma in the tokamak geometry is numerically found with a predominately diagonal and anisotropic pressure tensor. The state also admits a steady-state sub-sonic ion flow in the range of 10 km/s, agreeing with experimental observations [13, 14] and analytical calculations [15, 16]. Kinetic ballooning instability in the self-consistent kinetic steady state is simulated. It shows that high-n ballooning modes have larger growth rates than low-n global modes, and in the nonlinear phase the modes saturate approximately in 5 ion transit times ...
