复合材料热压工艺多物理场耦合数学模型

Multi-physics field numerical model for hot-pressing process of composite

针对热压工艺特点,将预浸料视为可变形的多孔介质,通过体积平均,建立了固化过程中温度、纤维应力和树脂流动多物理场耦合的数学模型。该模型考虑了纤维变形和体积分数变化的影响,反映了渗透率和纤维体积分数的关系。对于复合材料层合平板热压工艺,通过进一步简化,给出了一维固化方程,并进行了有限元数值分析。数值模拟中采用ALE移动网格方法来处理动边界问题。计算结果表明,与非耦合的经典模型相比,该模型给出的结果能更好地与实验吻合,层合板逐层压缩现象也和实验结果一致。而且该模型能预测树脂的排出量和纤维层间纤维体积分数的变化。

A multi-physics cure-thermal-stress-flow field coupling numerical model was developed by the volume averaging method for the hot-pressing processing, assuming that the prepregs are deformable porous medium. The fiber deformation, change of the volume fraction and permeability varied with the volume fraction of fiber were fully considered. A one-dimension curing model was developed and numerically solved by FEM for the composite laminate. ALE moving mesh method was used to treat the moving boundary. The result shows that the model proposed here has better agreement with experimental data than the classical models; the composite laminate was compressed pile by pile. This phenomenon tallies with experiment. The quantity of resin discharged and the variety of volume fraction of fiber in different piles were revealed by this model.