Faster Automatic Tetrahedral Elements Generation using Topological Mapping

Abstract

Preprocessing in a program for a 3-D finite element analysis, subdividing an analysis field into finite elements formed by tetrahedra, is usually much more complex compared with subdivision in 2-D field problems.
For encouraging the 3-D finite element analysis to practical use an automatic tetrahedral elements generation method should have the following prerequisites:
(1) Inputting data is easy and their amount is small.
(2) Mesh density control is easy.
(3) The shapes of generated elements are closer to that of regular tetrahedron.
(4) It is applicable even if the analysis field includes complicated objects.
(5) The processing time for generating elements is short.
In this paper, an automatic tetrahedral elements generation method satisfying all the conditions mentioned above is proposed: Manual operations required are only to divide an analysis region into several rectangular regions and a latticed wire frame for each region in consideration of suitable mesh density. Then the frames are mapped on objects, hexahedra generated from the frames are divided into tetrahedra, and then the shapes of tetrahedra are modified to the closer regular ones automatically.
The processing time is very short because of using mapping method.