基于扩展有限元法的结构内部r多缺陷的反演分析

摘要

An inverse model is proposed based on the extended finite element methods ( XFEM ) and a modified artificial bee colony( MABC) algorithm to detect and quantify the multiple internal flaws in structures.With this novel model, the location and the size of each flaw are approximated by the level set method. Moreover, a best-and-guided solution updating strategy is used during the global search until convergence is reached. The parameter samples with the different number of flaws are selected greedily by the artificial bee colony. The number of flaws, which is unkown in structures beforehand, is optimized during the iteration. This model avoids the problem of grid reclassification in the inversion process and reduces the amount of calculation for inverse analysis.The results of the numerical examples show that the proposed approach can detect and quantify the multiple internal flaws in structures and the corresponding locations and shapes without any knowledge of the number of flaws beforehand.%基于扩展有限元法和改进的人工蜂群智能优化算法,建立了检测和量化结构中多个内部缺陷的反演分析模型.反演分析模型中,由水平集函数来表征每个缺陷的位置及尺寸,采用精英加引导策略的人工蜂群搜索方程进行全局搜索,直到达到收敛为止;提出以人工蜂群对不同数目的缺陷参数样本进行贪婪选择,无需预先知道结构内部所含的缺陷数目,迭代过程中缺陷数目可以智能改变.该模型避免了反演过程中网格重划分问题,有效地减少了迭代的计算成本.通过若干算例的分析表明:在结构内部所含缺陷数目未知情况下,建立的反演分析模型能够快速准确地识别并确认出结构内部存在的缺陷数目及其相应的位置和大小.