无弯曲纤维织物面内渗透率的结构相关性

Structure-relationship of the in-plane permeability of non-crimped fabrics

建立无弯曲纤维织物(Non-crimped fabrics,NCF)的几何结构单胞,应用树脂在纤维束内与束间耦合流动的模型,数值模拟树脂的细观流动行为,结合Darcy定律,计算单胞的面内等效渗透率,并对计算方案进行验证。在此基础上,探讨织物的纤维束间距离、纤维束高度以及束内渗透率等细观结构参数与单胞面内等效渗透率之间的关系。结果表明:单胞面内等效渗透率随纤维束间距离的增大而增大,其倒数的对数之间呈正的线性关系;纤维束高度对单胞面内等效渗透率的影响类似于纤维束间距离对其的影响;单胞面内等效渗透率随纤维束内渗透率的增加而线性增加。

A unit cell of the non-crimped fabrics＇ geometrical structure was established,and the meso-level resin flow behavior within it was simulated by coupling the inter-tow and intra-tow flows.According to the Darcy＇s law,the equivalent in-plane permeability was calculated.And then this method was verified.Based on the above work,the relationship between the in-plane permeability of the unit cell and the meso-level structural parameters,such as the distance between fiber bundles,the fiber bundle＇s height and permeability,was investigated.The results show that the in-plane permeability of the unit cell increases with the increase of the distance between fiber bundles,and a positive linear relationship exists between the logarithms of their reciprocals;the height of fiber bundles has the similar effect on the permeability as the distance between fiber bundles does;the in-plane permeability of the unit cell increases linearly with the increase of the permeability of fiber bundles.