锪窝孔边扇形角裂纹应力强度因子的三维有限元分析

3D FINITE ELEMENT ANALYSIS OF SIF OF THE STRUCTURE WITH DIMPLE HOLE

根据航空等领域内锪窝铆接及锪窝锣接构件的典型结构特征 ,采用三维的十节点四面体等参有限单元模型 ,分别对无裂纹及孔边含裂纹锪窝孔 /直通孔结构进行了模拟分析 ;得到了锪窝孔构件的危险部位及90°,1 2 0°锪窝孔边扇形角裂纹的应力强度因子 ,给出了覆盖面广的计算曲线 ;通过对计算结果的分析 ,讨论了裂纹长度、孔径以及板厚等因素对应力强度因子的影响。和已有的文献比较表明 ,本文数值结果精确 ,方法可靠。

Dimple rivet joint and bolt joint are the typical fastening styles used in aerocraft. In a 3D finite element analysis (FEA) model, the dimple and straight hole structures with or without fanlike cracks around their holes are simulated. First, critical sits are obtained by the FEA of dimple hole structure without fanlike cracks around its hole. Second, the stress intensity factors (SIF) of the fanlike cracks around the dimple and straight hole are computed. Based on these SIF, some factors that will affect SIF generally, such as the crack length, hole radius and structure thickness, are discussed. The accuracy of the results and reliability of the numerical method and FEA model used in the paper have been demonstrated by comparisons between SIF about the straight hole obtained here and those in literature. Therefore, the numerical results and some conclusions given in this paper can be used as a basis for the damage tolerance design of dimple joints.