金属塑性成形有限元模拟中的六面体单元再划分技术研究进展

系统分析比较了各种六面体单元网格再划分方法的具体技术思路和优缺点 ,及其在模拟三维金属体积成形过程中的应用。结论指出 ,基于在任意几何形状的三维实体上实现全自动生成满足要求的六面体网格的通用算法非常复杂和困难 ,涉及许多具体的特殊问题的处理 ,而且基于畸变后边界节点生成满足拟合精度的几何实体也是如此。本文提出基于畸变网格的质量优化和局部网格加密 /稀释是最佳的解决方法 ,既可以保持初始网格的拓扑结构 ,还可以有效地避开网格再划分问题

Advance of hexahedral element remeshing methods for bulk metal forming process FEM simulation

Based on the author's accomplishments,this paper conducts the tradeoff study of several hexahedral element remeshing algorithms,and their applications into the simulation of the 3D bulk metal forming processes.As a result, the conclusions are drawn that it is hardly possible to automatically recreate the hexahedral elements with satisfied quality on an arbitrary 3D solid model, since the algorithm relates on how to handle many specific problems, such as geometric singularities and degeneration. In addition, it's also very difficult to generate the closed surface fitting the outer nodes of the deformed material, the details includes locating the vertex, surface edge and loop. So the best solution is to directly refine the distorted internal elements and boundary elements, and/or increase/decrease the local mesh density. In this way, the better topology of the initial mesh can be well kept, and the puzzle of remeshing can be effectively averted.