焊接有限元自适应四面体网格生成方法

Hybrid adaptive tetrahedral mesh generation method for finite element analysis of welding process

针对复杂焊接零件,提出了八叉树、前沿推进和约束Delaunay相结合的自适应四面体网格生成方法.基于微分几何原理,提出了任意复杂立体打印(STL)曲面的智能识别和自动分解方法;给出了基于曲率信息和焊缝、热源等位置信息的2种自适应网格尺寸控制点的自动化构造策略;利用八叉树背景栅格所生成的网格密度控制点,分别利用前沿推进法和约束Delaunay方法生成表面网格和体网格,实现了复杂焊接零件的高效率、智能化、自适应四面体网格生成.数值算例验证了算法的有效性.

A hybrid adaptive tetrahedral mesh generation method for complex welding products was developed. The hybrid method combines the octree, advancing front and constrained Delaunay based tetrahedral mesh generation methods. Based on differential geometry theory, an intelligent method was proposed to auto-recognize and auto-decompose arbitrary complex stereo lithography （STL） surface. Two automatic methods of adaptive mesh control points generation were presented based on surface curvature and geometrical position of the weld bead and the heat source. An efficient octree data structure was developed to organize the adaptive mesh size control points. A coupled advanced front and constrained Delaunay based method was used to generate the high quality adaptive tetrahedral meshes. Examples were given to demonstrate the practical performance of the algorithm.