Abstract
Due to the accuracy and the efficiency of hexahedral elements, automatic hexahedral mesh generation has a growing demand for finite element analysis. For this problem, several algorithms have been proposed by many researchers. However, reliable automatic hexahedral mesh generation has not been established yet. In this paper, a new strategy of fully automatic hexahedral mesh generation is proposed. In this strategy, the prerequisite for generating hexahedral is quadrilateral surface mesh. From the given surface mesh, combinatorial dual cycles (whisker sheet loops for whisker weaving algorithm) are generated to produce hexahedral mesh. Since generating good quality hexahedral mesh does not depend only on the quality of quadrilaterals of the surface mesh but also on the quality of the dual cycles generated from it, the method to remove self-intersections from dual cycles is proposed. The surface mesh modification procedure of the proposed method has three basic steps. These steps are (a) face collapsing, (b) new face generation and (c) template application. Next, automatic hexahedral mesh generator by the improved whisker-weaving algorithm has been developed in this paper. By introducing nodal placement technique, it becomes possible to generate hexahedral mesh with fewer bad-quality elements. Several examples will be presented to show the validity of the proposed mesh generation strategy.
