In this study, we examine whether the First-Order Taylor Expansion (FOTE) method can be applied to steady-state plasma flow fields in space. We particularly examine whether this method (termed FOTE-V) can be used to identify the flow critical points (including both stagnation point and vortex center) and reconstruct the flow patterns around these points. Quantitatively, we test the accuracy of this method using 3D kinetic simulation data, and find the FOTE-V method can give accurate reconstruction results within an area about 2 times the size of the spacecraft tetrahedron, particularly when there are no clear nonlinear flow structures in the simulation box. With simulation data, we also reveal the ability of the FOTE-V method on reconstructing 3D flow field topology of both radial-type null and spiral-type nulls. We further test the accuracy of this method using measurements from NASA’s Magnetospheric Multi-scale (MMS) mission. In a current sheet crossing event, the FOTE-V metho...

中文翻译：

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将FOTE方法扩展到三维等离子流场

在这项研究中，我们检查一阶泰勒展开（FOTE）方法是否可以应用于空间中的稳态等离子体流场。我们特别检查了这种方法（称为FOTE-V）是否可用于识别流动临界点（包括停滞点和涡流中心）并重构这些点周围的流动模式。定量地，我们使用3D动力学仿真数据测试了该方法的准确性，发现FOTE-V方法可以在航天器四面体尺寸的大约2倍的区域内给出准确的重建结果，尤其是在没有清晰的非线性流结构的情况下。模拟框。借助仿真数据，我们还揭示了FOTE-V方法重构径向型零点和螺旋型零点的3D流场拓扑的能力。我们使用NASA磁层多尺度（MMS）任务的测量结果进一步测试此方法的准确性。在当前的跨页活动中，FOTE-V方法...