热-机载荷下不规则夹杂的奇异性应力场分析

Singular stress analysis of an irregular shaped inclusion under thermo-mechanical loads

基于有限元特征分析法得到的夹杂角部场数值特征解开发了一种超级奇异单元模型,并将其与普通四节点单元紧密结合,用于热-机载荷下夹杂角端部的应力场分析。在数值计算中,考察了热-机载荷下不同弹性比和不同夹杂尺寸的应力强度因子,并将所得结果与文献解和传统有限元方法解比对。结果表明,本文方法对热-机耦合条件下的不规则夹杂角端部的热弹性应力分析极为有效,可避免局部网格的高度加密,并提高计算效率。模型在复合材料夹杂的局部强度问题分析方面具有很好的实用性。

A kind of super element is developed based on the numerical eigensolutions computed from an ad hoc finite element eigenanalysis method,then is incorporated with common standard four-node ele-ment for singular stress analyse of an irregular shaped inclusion under thermo-mechanical loads.In the numerical analysis,generalized stress intensity factors at the inclusion corner embedded in an infinite plate subj ected to thermo-mechanical loads are systematically calculated for various material stiffness ra-tios and inclusion dimensions,and the validity and applicability of this element are established through the present detailed finite element analyse.The present model can avoid highly refined meshes,improve the computational efficiency,and has great significance for analyse of the local strength of inclusions in composites.