Finite Element Mesh Generation Over 3D Surfaces & Integration Of CAD/CAE

The imperfection of Finite Element Mesh Generation (FEMG) Limits Finite Element Method (FEM) to be used extensively in engineering. The automatic triangular mesh generation over 3D surface is an important issue of the system of FEMG, so is front subject in computational mechanics field. In addition the compact integration of CAD/CAE is gradually receiving more and more attention by the academia and engineering circles. The main research contents of this paper is as following:1. Based on the mapping approach, a method of mesh generation triangulation over 3D parameter surface is presented: the Advantage Front Technique (AFT) is adopted and extended for mesh generation over parameter domain; the paper introduces Modified nodal density function is introduced which correlate with average law camber of the 3D surface, thus the formulated mesh density accords with crooked degree of the 3D surface; the ideal size of outlying is calculated in the parameter domain; as to regulate surface, the method of getting in reverse through tangent vector is introduced to obtain ideal point location in physical space, which improves the quality of surface mesh with high efficiency; and the method for judgement of segments crossing in AFT algorithm is improved , efficiency is higher than solving the traditional equation between two crossing segments.2. The method for finite element mesh generation over 3D periodic surface and degenerated periodic surfaces is presented: for the degenerated periodic surface, a preprocess method is proposed to deal with the un-integriry problem of its parametric domain loops; the front shift method is proposed, which makes traditional AFT method still be applied normally; by checking dispersed edges information of degraded surface, inserting a point on the edge, the edges' property will be come back; the method of mapping through tangent vector is introduced to obtain ideal point location in physical space, which improves the mesh quality around the poles.3. The compact CAD/CAE integration method is investigated, and integration between CAXA CAD system and JIFEX CAE system is implemented.