基于区域叠合有限元技术预测三维编织复合材料弹性性能

本文基于区域叠合有限元技术预测三维四向编织复合材料弹性性能。在该方法中,分别建立相互独立的纤维增强相有限元模型和复合材料整体区域(包括所有增强相和基体相所占几何空间)有限元模型,两相模型在空间叠合组成复合材料模型,运用节点自由度耦合技术使两相模型满足变形协调关系,通过对两相模型赋予适当的材料属性以使所建复合材料模型具有与实际复合材料等效的力学特性。该方法较传统方法显著缩短了建模时间,降低了建模难度。区域叠合法的数值模拟结果与传统方法预测结果一致。本文的研究为进一步研究编织复合材料非线性宏观力学特性和渐进损伤过程模拟奠定基础。

Prediction of elastic properties of 3D braided composite using domain superposition technique

A domain superposition technique(DST) is implemented for prediction of the elastic properties of three-dimensional four-directional braided composites in this paper.Using the DST model,the reinforcement domain and the global domain which are mutual independently are built respectively into FE meshes instead of explicitly modeling the reinforcement domain and the matrix domain formed using the traditional finite element method(FEM).During solving,the reinforcement FE meshes are coupled into the global FE mesh using nodal degree of freedom coupling technique.Accordingly the material models are adjusted to ensure that the DST implementation is an accurate representation of the actual composites system.The establishing model process of FE meshes for DST are much easier than that of traditional FEM.Numerical results show that the DST results are correlation and coincident with that of traditional FE analysis.The results in this paper is a basis for further development of efficient numerical models and for prediction of the nonlinear macroscopic mechanical properties and simulation of the progressive damage process of the braided composites.