文中以多尺度有限元法为基础,建立了 2D编织纤维纱线和编织结构的RVE(representative element volume)模型.通过施加周期性边界条件、6个方向拉伸剪切荷载计算编织复合材料和单向纤维复合材料的刚度矩阵.校核评估NASA经验公式与修正混合法则均匀化理论公式这两种单向纤维复合材料工程常数计算公式的准确度.通过对单向纤维复合材料和编织复合材料的工程常数计算结果的对比,总结同体积分数下两种类型复合材料弹性模量与剪切模量之间的等效关系,并依据均匀化理论、双层板假设,推导编织复合材料泊松比计算公式.以单向纤维复合材料工程常数计算公式预测2D编织复合材料工程常数的计算方法.
Analysis of Mechanical Properties of 2D Woven Composites Based on Multi-scale Finite Element Method
Based on the multi-scale finite element method,the RVE(Representative Element Volume)model of 2D braided fiber yarn and braided structure was established.The stiffness matrices of brai-ded composites and unidirectional fiber composites were calculated by applying periodic boundary con-ditions and tensile shear loads in six directions.By checking and evaluating the accuracy of NASA em-pirical formula and modified mixing rule homogenization theory formula,the engineering constants of unidirectional fiber composites were calculated.By comparing the calculation results of engineering constants of unidirectional fiber composites and braided composites,the equivalent relationship be-tween elastic modulus and shear modulus of the two types of composites with the same volume fraction was summarized.According to the homogenization theory and the hypothesis of double-layer plate,the calculation formula of Poisson's ratio of braided composites was deduced.A calculation method for predicting the engineering constant of 2D braided composites by using the formula for calculating the engineering constant of unidirectional fiber composites was proposed.
万方数据
维普
