摘要
高强钢作为弹体结构设计中最常用的一种材料,针对其在冲击载荷下断裂破坏特性的数值模拟研究一直以来都受到研究人员重视.此类问题通常涉及材料在高温、高压、高应变率环境下的动态响应与破坏.因而本文提出了一种Euler网格与Lagrange标志点相耦合的局部标志点映射算法.该算法在Euler网格中添加带正六面体影响域的标志点,根据标志点与网格的拓扑关系,通过影响域加权将网格物理量映射到标志点上.基于MPI标准编写了三维并行程序代码,在程序中引入Johnson-Cook本构关系与等效应变断裂判据,对钢板在爆炸载荷作用下的破坏行为进行了数值模拟.与实验结果的对比表明,本文提出的算法结合了Euler方法和Lagrange方法的优点,能很好地处理材料的大变形及破坏过程,同时保证了计算精度和效率,可以更好地应用于各类冲击问题的数值模拟研究.
As one of the most common material used for projectile, the numerical simulation about high strength steel about its fracture characteristics under impact loading has always been emphasized. These kinds of problem often involved in the non-linear dynamic response and fracture of multi-material at high temperatures and pressures and strain rate. We put forwards a kind of mapping algorithm about local marked particles through coupling Lagrangian particles and Eulerian meshes. It is obtained by adding marked particles with regular hexahedral influence domain. According to the topological relation between particles and cells, the physical variables of cell are mapped to particles by weighted influence domain. Based on MPI standards, 3D parallel multi-material program with particles was developed. Besides, Johnson-Cook constitutive equation and fracture criterion about effective strain. A series of penetration in different working conditions were simulated and compared with experiment. It is found that the algorithm, which combines the best feature of Eulerian method and Lagrangian method, could be applied in simulating large deformation and fracture process of metal material. At the same time, the computational efficiency and accuracy could also be guaranteed. It is concluded that the improvement could make the algorithm more suitable for the simulation of various impact dynamic problems.
出处
《中国科学：技术科学》
EI
CSCD
北大核心
2016年第4期357-367,共11页
Scientia Sinica(Technologica)
基金
国家自然科学基金(批准号:11390363)资助项目
关键词
标志点法
数值模拟
并行计算
断裂特性
marked particles, numerical simulation, parallel computing, fracture characteristics
