Surface mesh generation is still one of the most challenging and difficult prerequisites for various numerical simulations, and especially for large-scale volumetric mesh generation. Existing approaches can be essentially categorized into two kinds: direct and indirect [1]. In the direct approach, mesh is generated directly on the surface in 3D such as the Octree-based method and the Advancing Front method. The indirect approach relies on the generation in the parametric domain using Advancing Front method, Delaunay-based technique, or any 2D mesh generation technique [1]. The mesh is then mapped onto the surface using the reverse mapping. The direct methods obviously have the difficulty in mesh validity checking, while the indirect methods are facing the trouble to control the sizing and shapes of the elements to be generated in the 2D region. Accordingly, it is still very time-consuming for generating large-scale surface meshes of sufficient quality.In this paper a new surface mesh generation method is described for efficient automatic generation of high-quality surface grids based on remeshing technique [2]. Supported geometry import formats include composite parametric surface with analytic definition or discrete composite parametric Ferguson curve and surfaces. Initially, for each independent surface patch, a boundary triangulation is generated in the parametric domain, and these patch meshes are mapped onto the surface and assembled into the beginning surface mesh conformingly. Next, remeshing techniques including edges splitting and contraction are utilized for the refinement or coarsening of this initial surface mesh. Metric controlled edge length is computed with respect to surface curvature or coupled with user-specified spacing, both for isotropic or anisotropic cases. Grid points are added accurately through edges splitting using the surface definition; edges contractions are performed robustly with help of determinants computation of triangles in the parametric domain related to the contracted edge. After the refinement, the surface mesh is optimized through edges swapping and points relocation. All the operations are locally performed and high efficiency is resulted. Above one million elements with high quality can be generated in less than one minute in a PC with reasonable CPU speed. Furthermore, small-angle elements due to neighboring patches interface can be avoided by the remeshing techniques naturally. Also, the existing method can be used directly for remeshing surfaces with SGL, STL, IGES formats as geometry input. At the end of the paper, various complex geometry configurations, such as fighter-type aircraft, human organs such as heart and kidney are tested as examples to demonstrate the capabilities of this approach.
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