变角度纤维复合材料环扇形层合板的自由振动分析

与传统的直线纤维增强复合材料相比，变角度纤维复合材料具有更强的可设计性，为改善结构性能提供了更大的可能．鉴于此，本文将研究纤维的变角度铺设对复合材料环扇形层合板的自振频率及振动模态的影响．假设纤维的方向角沿环扇形板的径向线性变化，基于经典的层合板理论，采用微分求积法获得了环扇形层合板自由振动问题的数值解．通过与现有文献及ABAQUS有限元结果的比较验证了本文模型及方法的正确性和收敛性，并详细分析了纤维起始角和终止角的变化对层合板的自振频率及振动模态的影响．研究结果表明：与常刚度层合板相比，变角度纤维复合材料层合板的基频具有更大的调整空间，通过合理选择纤维起始角和终止角可有效提高层合板的基频．研究结果可为该种新型复合材料结构的优化设计提供一定的参考．

Free Vibration Analysis of VAT Laminated Annular Sector Plates

Compared with the traditional linear fiber-reinforced composite, Variable Angle Tow (VAT) composite has better designability, which provides a greater possibility to improve the structural performance. In view of this, this paper will study the free vibration of VAT laminated annular sector plate. It is assumed that the orientation angle of the fiber varies linearly along the radial direction of VAT annular sector plate. Based on the classical laminated plate theory, the numerical solution of the free vibration of VAT laminated plate is obtained by the Differential Quadrature Method (DQM). Compared with the existing and ABAQUS results, the correctness and convergence of the present method are verified. The influence of the fiber start angle and the end angle on the natural frequency and vibration mode of VAT laminated annular sector plate is analyzed in details. The results show that the fundamental frequency of VAT laminate has more possibility to be adjusted than that of the laminate with constant stiffness. The fundamental frequency of VAT laminate can be effectively increased by properly selecting the start angle and the end angle of the fiber. The results can provide some reference for the optimal design of this new composite structure.