Generation And Application Of Tetrahedron Mesh Based On Closed Surface

Tetrahedron is simplex in three dimensions, Tetrahedron have greater flexibility, infinitely approaching the border region and having better adaptability geometry, often use and research in meshing field. The tetrahedral mesh generation has many classical algorithms, for example Delaunay, advancing-front, and Mapping methods. With the deepening of research, many new methods have been proposed to solve different practical problems. Mesh refinement is an important aspect when generating tetrahedral mesh, to generate high quality tetrahedron is the guarantee of precision in engineering problems.This paper studied tetrahedral mesh generation algorithm based on closed surface, implementing Validity Check to the model before meshing. Proposing close checking, non-manifold checking, surface normal vector checking and intersect checking through analyzing various models, at the same time adjusting the model according to the feedback error messages, which can ensure models meet the conditions. This paper analyzes tetrahedral meshing of closed surface with three aspects of tetrahedral unit generated, analyzing convergence and tetrahedral mesh optimization. After tetrahedral meshing, verifying whether mesh quality conformed to accuracy of practical problems, if it is fulfilled, applied to engineering problem. In order to use algorithm easily, this paper designs an interactive interface. Boundary consistency and element quality are two key and difficult points in tetrahedral generation. This proves that no points were added on the constraint surface of closed models in Netgen-based algorithm, which leads to the high consistency between the original surface and the tetrahedron shape and ensures the accuracy of the model and boundary consistency under co planarity. Sample applications in geological model and industrial model both show that the Netgen-based algorithm is stable and efficient when dealing with large curvature models, ultra-thin models, adjacent models or containing models.