纤维位置随机引起的复合材料性能分散性研究

采用Monte-Carlo方法分别用均匀分布和正态分布模拟复合材料纤维中心位置的随机变化,得到材料截面图像。然后用像素对材料截面图进行网格划分,作为通用单胞模型的输入,计算出复合材料性能的子样。最后用数理统计的方法处理数据得到材料性能的统计特性数据。分析结果表明:本文采用的模拟方法是合理有效的。由纤维位置变化引起的材料分散性随纤维体积比的变化先增大然后减小。三参数威布尔分布和正态分布较好地描述了各个弹性参数的分布。 

Research on the Discrepancy of Composite Effective Properties Induced by the Stochastic Fiber Location

Based on Monte-Carlo method,uniform simulation and Gaussian simulation were used to simulate the stochastic fiber location.The digital images of the material cross-section were generated by the simulation method.Grids were generated by meshing the digital image pixels.Based on these grids a GMC (General Method of Cell) method is used to calculate the composite elastic properties.Then,the properties were analyzed by statistic method.The results show that the simulation methods accurately represent the stochastic fiber location.The discrepancy of elastic properties increased with the vf (volume fraction of fiber) when the vf is low and decreased with vf when the vf is high. The three-parameter Weibull pdf and Gaussian pdf describe the distributions of every elastic coefficient accurately.