New Algorithm of Automatic FEM Mesh Generation for Electromagnetic Scattering Calculation

Automatic mesh generation for finite element method (FEM) plays an important role in electromagnetic scattering calculation. A new algorithm for the automatic generation of finite element meshes is presented. The methodology is a grid-based approach type. Take advantage of it, the algorithm improve the traditional mesh generation scheme thanks to the integration of simple and flexible density control and the rationalization of boundary discretization. In two dimensional cases, the original domain is separated into squares, and then all interior squares are split into isosceles right triangle, which results in uniform meshes with excellent internal triangles like the Almost Regular Triangulations. According to different condition, the squares which intersect the boundary of the domain are adjusted to triangles. A new algorithm is presented for improving the quality of the meshes near to the boundary. In three dimensional cases, it´s similar. Compared with other methods, it´s capable of automatically and adaptively generating meshes with reasonable quality, and is easy to implement in program. Also it achieves good quality of mesh. These characteristics have been demonstrated by the examples in the paper.