丝束变角度层合板频率性能的参数化分析与优化

PARAMETRIC ANALYSIS AND OPTIMIZATION OF FREQUENCY PROPERTY OF VARIABLE ANGLE TOW LAMINATES

为有效设计丝束变角度(VAT)层合板的频率性能,首先基于纤维方向角的线性变化定义建立了VAT层合板参数化有限元模型,开展了VAT层合板频率性能的参数化研究;其次,基于纤维轨迹的周期性特征,对比分析了VAT层合板不同长宽比和厚度对频率性能的影响;最后,结合序列响应面方法,完成了不同边界下最优化VAT层合板频率特性的纤维轨迹参数设计。计算结果表明,VAT层合板的一阶频率基本不受纤维参考方向角影响,而优化纤维参考方向角能有效提高一二阶频率带隙;特征长度对频率特性的影响随长宽比增大而衰减;越薄的VAT层合板其频率特性受纤维轨迹的影响越大。研究结果为VAT层合板的频率性能设计提供了参考。

The aim of this paper is to trace the influence of fiber path parameters on frequency property so as to design VAT laminates effectively. Firstly,the parametric finite element model of VAT laminate was established to investigate effect of path parameters on the frequency property,by utilizing the definition of linear variation of fiber angle. Secondly,influences of aspect ratio and thickness of VAT laminate on frequency characteristic were analyzed and discussed based on the periodical distribution of fiber path. Finally,optimization design fiber path of square VAT laminate was conducted under different boundary conditions using sequential response surface method,for maximizing the first order frequency and the difference of first and second order frequency. The results show that the band gap of first and second order frequency of VAT laminates can be effectively improved by the optimization of fiber reference direction angle,which has little influence on the first order frequency. Effect of characteristic length on frequency performance is decreasing with increasing aspect ratio. The thinner VAT laminates,the greater the impact of fiber path on frequency performance. The results provide guidance for frequency performance design of VAT laminates.