摘要
单位分解扩展无网格法(PUEM)是一种求解不连续问题的新型无网格方法。其基于单位分解思想,通过在传统无网格法的近似函数中加入扩展项来反映由裂纹所产生的不连续位移场。详细描述了水平集方法,PUEM不连续近似函数的构造及控制方程的离散。针对裂纹扩展问题,提出了一种十分简单的水平集更新算法;讨论了不同的节点数、高斯积分阶次以及围线积分区域对应力强度因子计算结果的影响,并给出了合理的参数;模拟了边裂纹和中心裂纹的扩展问题,并与XFEM的数值结果进行了比较。数值算例表明,本文方法具有较高的计算精度,是模拟裂纹扩展非常有效的方法,具有广阔的应用前景。
The enriched meshless method based on the method for modeling discontinuities. In PUEM,in order partition of unity（PUEM） is a new numerical to represent the discontinuous displacement field around crack,enriched {unctions were added in the approximation of traditional meshless based on the ideas of partition of unity. The theory of level set,construction of discontinuous approximation function and discrete format of governing equation were introduced in detail. In view of crack growth,a simple up- dating algorithm of level set was presented. The impact for the computational results of stress intensity factors using different nodal numbers,Gaussian integral orders of background cells and integral domain of crack tip were discussed. Both growth examples including edge and centre crack were simulated by the combination of PUEM and the level set method. The results of numerical examples show PUEM has higher accuracy,and is an effective meshless method for crack propagation.
出处
《计算力学学报》
CAS
CSCD
北大核心
2013年第1期28-33,共6页
Chinese Journal of Computational Mechanics
基金
国家自然科学基金(10972180
61001156
51269024)资助项目
关键词
裂纹扩展
单位分解
无网格方法
应力强度因子
crack growth
partition of unity
meshless method
stress intensity factors
