Intelligent Local Approach for Automatic Hexahedral Mesh Generation

2nd Symposium on Trends in Unstructured Mesh Generation, University of Colorado, Boulder, August 1999

MESHING
RESEARCH
CORNER

School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 JAPAN
wada@garlic.q.t.utokyo.ac.jp

Abstract
Unstructured mesh generation for the FEM is in general a very labor-intensive and time-consuming process. Recently, the portion of the mesh generation process in the analysis increases, because the model of analysis tends to become very complex and the complexity of mesh also increases. Quadrilateral elements and hexahedral elements, the automatic generation of which is still an open problem, are strongly demanded for some problems. This is because these elements are more suitable to strongly nonlinear problems than triangular and tetrahedral elements, and large aspect ratio elements are usable. Some hexahedral mesh generation method such as Paving and Plastering method [1-2], Whisker Weaving[3] and HEXAR [4] have been developed. However, these methods sometimes fail to generate meshes and cannot control element size and aspect ratio as human does manually. An automated mesh generation method named Intelligent Local Approach (ILA)[5], which can control both size and aspect ratio of hexahedral element, will be presented. To efficiently deal with the complicated geometrical constraints for high quality hexahedral elements, a fuzzy knowledge processing technique is effectively utilized. ILA is applied to mechanical parts and CFD model. In the present paper performances of ILA are demonstrated and discussed in detail.

References

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