模拟动断裂问题的多尺度扩展有限元方法  

Multi-scale XFEM for Simulating Dynamic Fracture

作　　者：张凝 尹硕辉 赵子衡 ZHANG Ning;YIN Shuohui;ZHAO Ziheng(School of Mechanical Engineering,Xiangtan University,Xiangtan 411105,Hu′nan,China)

机构地区：[1]湘潭大学机械工程学院,湖南湘潭411105

出　　处：《机械科学与技术》2022年第5期695-702,共8页Mechanical Science and Technology for Aerospace Engineering

摘　　要：提出一种分析弹性固体动态断裂的多尺度扩展有限元方法。该方法采用局部网格细化对网格模型中裂纹部分进行处理,并利用可变结点单元连接不同尺度网格单元,在提高数值计算精度的基础上,节省了计算成本;利用隐式Newmark时间积分和相互作用积分求动应力强度因子。通过算例数值计算结果与已有文献结果进行对比,验证方法优劣性。结果表明:多尺度扩展有限元方法是模拟弹性结构动断裂的一种有效数值方法,相较于标准扩展有限元方法具有更高的精度。A multi-scale extend finite element method(XFEM)for analyzing the dynamic fracture of elastic solids is proposed.The present method uses local mesh refinement to process the cracks in the mesh model,and variable-node elements is used to connect different scale mesh elements,which saves calculation costs on the basis of improving the accuracy of numerical calculations;implicit Newmark time integration and the interaction integral is used to solve the dynamic intensity factor.The calculated results of the calculation examples are compared with those of the existing literature to verify the pros and cons of the method.The results show that the multi-scale XFEM is an effective numerical method for simulating the dynamic fracture of elastic structures,and it has higher accuracy than the standard XFEM.

关 键 词：动态断裂 扩展有限元 可变结点单元 动应力强度因子 

分 类 号：O346.1[理学—固体力学]