摘要
基于ABAQUS有限元分析平台和UEL用户自定义单元接口,采用Matlab编制了扩展有限元的分析程序,对单边裂纹有限板条试件进行了扩展有限元模拟,并用位移外推法计算了裂纹的应力强度因子,探讨了网格密度和积分区域尺寸以及积分点个数对计算应力强度因子精度的影响。数值结果表明:细化网格可以显著提高有限元的计算精度,但由于扩展有限元本身精度较高,细化网格对提高扩展有限元计算精度的效果不明显;合理确定富集单元积分区域范围以及增加积分点个数都可以提高计算精度。
An extended finite element analysis program(XFEM) is compiled by Matlab which based on finite element analysis platform ABAQUS and user-defined unit UEL. The extended finite element simulation of a striped specimen with single edge crack was carried out,and the stress intensity factor of crack on the specimen was calculated by displacement extrapolation method. The effects of mesh density,integral region size and the number of integral points on the stress intensity factor were discussed. Numerical results show that mesh refinement of classical finite element method can significantly improve the accuracy of the stress intensity factor. Due to high accuracy of extended finite element method,melioration of mesh refinement is not obvious for XFEM method. Determiningintegral region size and number of integration points reasonably can improve the calculation accuracy.
引文
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