Three-Dimension Tetrahedral Mesh Optimization Method And Program Achieved

Automatic mesh generation method, such as AFT (Advancing Front Technique), Delaunay triangulation algorithm, and octree algorithm may generate poorly shaped or distorted elements, which cause numerical difficulties during the solution process. And for the meshes with highly distorted elements, the solution is both less accurate and more difficult to compute. This problem is more severe in three dimensions than in two dimensions, because tetrahedral can be distorted to poor quality in more ways than triangles. Compared with triangular meshes, tetrahedral meshes tend to have a larger proportion of poor quality elements and to have elements that are more severely distorted.A number of algorithms of finite element mesh optimization used extensively are introduced summarily at first. Then the algorithm combining the extended sliver decomposition method and Laplacian smoothing method in three-dimensional problem are investigated with much emphasis. By the end, several mesh generation examples using the algorithm.The problem of sliver element occurs commonly during the tetrahedral mesh generation process. For the different mesh generation technique, the generation form of sliver elements is different Because sliver element is shaped or distorted element, which cause numerical difficulties during the solution process, so it must be repaired.To meet the need of finite element analysis, an effective algorithm for three-dimensional tetrahedral mesh optimization is proposed in this paper. The sliver decomposition method is extended to deal with all kinds of poor quality element, all the poor quality elements below the specified quality factor in finite element mesh can be effectively removed. And then, a new mesh optimization method combining the extended sliver decomposition method and Laplacian smoothing method is proposed to overcome the problem of un-isolated poor quality elements frequently occurred in finite element mesh generation.According to the above-mentioned algorithm, a program is implemented in C language. Computational experiments show that the algorithm proposed is robust, efficient and easy to be implemented in practical applications.