基于FE/EFG耦合算法的虚拟裂纹闭合法  

Virtual Crack Closure Technique Based on Coupled FE/EFG Method

作　　者：王维说[1] 常学平[2] 

机构地区：[1]重庆大学土木工程学院,重庆400044 [2]西南石油大学机电工程学院,四川成都610500

出　　处：《四川大学学报（工程科学版）》2011年第6期64-69,共6页Journal of Sichuan University (Engineering Science Edition)

基　　金：四川省教育厅资助科研资助项目(09ZB101);西南石油大学校级科技基金资助项目(2010XJZ142)

摘　　要：在裂纹附近区域采用无网格伽辽金(EFG)节点,其余区域采用常规有限单元(FE)节点进行数值离散并求解,获得含裂纹构件的位移场。在裂纹尖端及其附近设置局部辅助有限单元区域,用于求解裂纹尖端处的2个特征参数:裂纹尖端节点力以及靠近裂纹尖端处裂纹面的位移。由这2个参数得到裂纹尖端处的应变能释放率,进而求得相应的应力强度因子,此方法为计算应力强度因子的EFG虚拟裂纹闭合法。数值算例表明,采用EFG虚拟裂纹闭合法能够有效计算裂纹尖端处的应力强度因子。A virtual crack closure technique based on EFG method for thread-shape crack was introduced.The cracked component was discretized and the displacement field was determined using a coupled FE/EFG method,by which EFG nodes were arranged in the vicinity of crack tip and FE elements in the remain part in order to improve computational efficiency.Two typical parameters,nodal force and crack opening displacement attached to crack tip were calculated by means of setting up an auxiliary FE zone around crack tip.Strain energy release rate（SERR）,further stress intensity factor（SIF） were determined by the two parameters.The method to calculate SIF was named as virtual crack closure technique based on EFG method.Several numerical examples using the presented method showed that SIF on the crack tip can be obtained accurately.

关 键 词：应变能释放率 虚拟裂纹闭合法 应力强度因子 EFG 数值求解 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]