摘要(英) |
Before performing mold flow analysis, it is necessary to convert the CAD model into a solid mesh for subsequent calculation in the analysis software. At present, the development of tetrahedral mesh is relatively mature, and its application is relatively common. However, in order to reduce the overall number of grids and achieve the purpose of reducing calculation time, it is necessary to construct a hexahedral grid for mold flow analysis. Before generating the hexahedral solid mesh, the quadrilateral surface mesh must be constructed, but there are still many problems in generating high-quality quadrilateral mesh. This study proposes a method that considers the neighbor relationship of mesh vertices to improve the quality of quadrilateral meshes. First, this research uses the B-rep structure data to classify each silhouette edge on the surface, and constructs uniform or non-uniform contour nodes through the classification results. Then, apply the mesh automatic construction technology developed in this laboratory for mesh generation, and finally use the quality restoration algorithm developed in this research to improve the final quality of the mesh, including smoothing and mesh merging procedures. Finally, the generated quadrilateral mesh is evaluated by aspect ratio and minimum angle, and analyzed according to the results. In all test cases, 99.8% of the points can correctly assist mesh construction, and after quality repair, the quality is not good. Good grids account for less than 1% of the total number of grids, so it is proved that this research uses correct auxiliary grid construction and improves its grid quality to make the overall grid quality excellent. |
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