摘要
以多层机织布为对象,首先基于两个分别对应于两种典型叠加模式的单元结构模型,通过理论分析,建立了多层机织布纵向切面内气泡形成的分析模型;然后采用有限元-控制体积方法对单元结构内树脂的扩散及气泡形成的过程进行了数值模拟。理论分析和数值模拟的结果符合一致,均表明:不同局部区域差异很大的渗透系数是气泡形成的最根本原因,而纬线的轴向渗透系数和经线的横向渗透系数之比对多层机织布纵向切面内气泡的形成及尺度起着决定性的作用。
The void formation during the RTM processing seems to be inevitable and the presence of voids has a deleterious effect on the mechanical properties of textile composites. The purpose is to investigate the mechanism of void formation in multi-layer woven fabrics. Two unit cell models were suggested to represent the cross sections of multi-layer woven fabrics with two typical layering patterns. Based on these two geometrical models, an analytical model was developed to describe the mechanism of void formation during the RTM processing. The flow fronts and void formations in these two cells were also numerically simulated using a control-volume method. The simulated results agree well with those predicted by the analytical model. The results show that, for a given fiber preform, the ratio of the weft axial permeability Kba to the warp transverse permeability Kbt is responsible for the size of the void formed in multi-layer woven fabrics.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2003年第3期57-63,共7页
Acta Materiae Compositae Sinica
基金
香港理工大学和香港特别行政区RGC项目的资助(B.14.37.Q400)
关键词
复合材料
RTM
气泡
多层机织布
渗透系数
Fabrics
Mathematical models
Mechanical permeability
Mechanical properties
Multilayers
