用广义扩展有限元计算界面裂纹应力强度因子  

SIFs of interfacial crack using generalized extended finite element method

作　　者：苏毅[1] 王生楠[1] 鲁龙坤 

机构地区：[1]西北工业大学航空学院,西安710072

出　　处：《北京航空航天大学学报》2016年第6期1162-1168,共7页Journal of Beijing University of Aeronautics and Astronautics

基　　金：航空科学基金(2010ZF56016)~~

摘　　要：广义扩展有限元法(GXFEM)是一种结合广义有限元法和扩展有限元法特点的新的数值模拟方法。给出了分析双材料界面裂纹应力强度因子(SIF)的广义扩展有限元法的基本原理。提出了一种新的双材料界面裂纹尖端富集函数,将裂纹尖端富集函数由12项缩减为6项。双材料界面不连续,在常规有限元法的位移模式中加入基于水平集的富集函数,同时将裂纹单元结点和裂纹尖端单元结点自由度广义化,提高了计算精度。通过与文献结果的比较,表明了提出方法的精确度和可靠度。Generalized extended finite element method（ GXFEM） is a new numerical simulation method which combines both the generalized finite element and the extended finite element. The principle of the generalized extended finite element method for analyzing the stress intensity factor（ SIF） of bi-material interfacial cracks is proposed. A new enriched function for bi-material interfacial crack tip is proposed,and the twelve crack tip enriched functions are reduced to the six ones. Because of the discontinuity of bi-material interface,enrichment functions based on level set are added in the displacement mode of the conventional finite element method. And the node freedom of the crack element and crack tip element are also generalized. Besides,the calculation precision is improved. A comparison of literature method and GXFEM calculations of numerical examples shows the the accuracy and reliability of the proposed method.

关 键 词：广义扩展有限元法(GXFEM) 界面裂纹 裂纹尖端富集函数 水平集 应力强度因子(SIF) 

分 类 号：O346.1[理学—固体力学]