Automatic Generation of 3-D Finite Element Meshes: Part(II) -Mesh Generation from Tetrahedron-based Octree-

삼차원 유한요소의 자동생성 (2) -사면체 옥트리로부터의 유한요소 생성-

Given the tetrahedron-based octree approximation of a solid as described in part(I) of this thesis, in this part(II) a systematic procedure of 'boundary moving' is developed for the fully automatic generation of 3D finite element meshes. The algorithm moves some vertices of the octants near the boundary onto the exact surface of a solid without transforming the topology of octree leaf elements. As a result, the inner octree leaf elements can be used as exact tetrahedral finite element meshes. In addition, as a quality measure of a tetrahedral element, 'shape value' is propopsed and used for the generation of better finite elements during the boundary moving process.