MENG Xiangqiao, LIU Zhiwei, LIU Taoran, et al. Auto-generation algorithm of surface meshes on dirty geometries[J]. 2022, 40(5): 186-194.DOI: 10.7638/kqdlxxb-2021.0400.
Auto-generation algorithm of surface meshes on dirty geometries
Dirty geometry is a geometric model with issues such as normal errors
intersections
slits and overlaps
which are unavoidable for generating meshes directly on the original boundaries. As a result
it is challenging to directly generate topologically compatible surface meshes on dirty geometries
and subsequent numerical analyses can thus be affected. The present study implements a dirty geometry mesh generation algorithm based on tetrahedral meshes
and the core idea of the algorithm is that the surface of an effective tetrahedral mesh must be an effective curved one. Our method performs normal repairment on discrete representations to generate tetrahedral meshes
solves the intersection via cutting tetrahedrons by discrete boundaries
and eliminates slits based on tetrahedron quality optimization. The surface mesh quality is further improved with surface remeshing under the guidance of the geometry size. The view sampling method is used to achieve normal restoration and fulfil the quality requirements in all directions. The multi-level energy thresholds are adopted to improve the efficiency of the tetrahedral optimization. Numerical test results suggest that the present auto-generation algorithm of curved surface meshes on dirty geometries is robust and efficient.
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references
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