The numerical analysis of electromagnetic devices by means of finite element methods (FEM) is often hindered by the need to incorporate the surrounding domain. The discretisation of the air may become complex and has to be truncated by artificial boundaries incurring a modelling error. Even more problematic are moving parts that require tedious re-meshing and mapping techniques. In this work, we tackle these problems by using the boundary element method (BEM) in conjunction with FEM. Whereas the solid parts of the electrical device are discretised by FEM, which can easily account for material non-linearities, the surrounding domain is represented by BEM, which requires only a surface discretisation. This approach completely avoids an air mesh and its re-meshing during the simulation with moving or deforming parts. Our approach is robust, shows optimal complexity, and provides an accurate calculation of electromagnetic forces that are required to study the mechanical behaviour of the device.

中文翻译：

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带有移动部件的电磁设备 - 使用 FEM/BEM 耦合进行仿真

通过有限元方法 (FEM) 对电磁设备进行数值分析通常会因需要纳入周围域而受到阻碍。空气的离散化可能会变得复杂，并且必须被导致建模错误的人为边界截断。更成问题的是需要繁琐的重新划分网格和映射技术的移动部件。在这项工作中，我们通过将边界元法 (BEM) 与 FEM 结合使用来解决这些问题。电气设备的实体部分由 FEM 离散化，可以很容易地解释材料非线性，而周围域由 BEM 表示，它只需要表面离散化。这种方法完全避免了空气网格及其在模拟过程中对移动或变形部件的重新划分。我们的方法是稳健的，