夹层式复合材料成型建模与敏感度分析

Forming modeling and sensitivity analysis of sandwich composites

本文通过对夹层结构在固化过程中的树脂状态进行分析,对夹层结构建立了等效分析模型,并运用代理模型技术研究了固化过程中模具的热膨账系数,面板的热膨账系数、弹性模量、蜂窝尺寸等参数对夹层结构收缩量和圆度误差的影响。首先,采用有限元仿真的方法对夹层结构在固化过程中的应力和变形进行了模拟;其中,建立了蜂窝等效模型,并利用生死单元技术对树脂在固化过程中的变化进行等效建模。仿真结果与实际相符,结果表明树脂在成型中的状态变化是影响夹层结构收缩的主要因素。然后,利用径向基函数(RBF)模型建立了收缩量和圆度误差与影响参数之间的关系。最后,探讨了夹层结构的收缩量及圆度误差的影响参数的敏感度。结果表明:夹层结构的收缩量对于模具热膨账系数和面板热膨账系数最敏感,树脂的热膨账系数是影响夹层结构圆度误差最敏感的因素。

In this paper,through analyzing the resin state,the numerical simulation is built for the Sandwich and the surrogate model is used to explore the influence of the thermal expansion coefficient of the mold and panel,the elastic modulus of the panel,the honeycomb size and other parameters on the shrinkage and roundness error dur ing curing process.First of all,the finite element method is used to simulate the stress and deformation of the sandwich during curing process.Among them,the honeycomb equivalent model is established and the life and death cell technology is applied to perform equivalent modeling of the resin state change.The simulation results match the actual.The results show that the state change of the resin during molding is the main factor affecting the shrinkage of the sandwich structure.Secondly,the relationship between the shrinkage rate or roundness error and te influencing parameters is established by using te radial basis function(RBF).Finally,te sensitivity of te influence parameters of the shrinkage and roundness error is discussed.The results show that the thermal expan sion coefficient of the mold and the thermal expansion coefficient of the panel are the most sensitive to the shrink age of the sandwich structure and the most sensitive factor afecting the roundness error of the sandwich structure is the coefficient of thermal expansion of resin.