阻尼层复合材料夹芯梁的动力学性能

Dynamic properties of damping layer composite sandwich beam

采用哈密尔顿原理,推导得到了阻尼层复合材料夹芯梁的偏微分振动平衡方程;使用Navier型闭环解得到梁的固有频率和损耗因子,并与其他文献中的解进行对比验证;最终揭示了夹芯复合材料梁动力学性能随结构参数的变化。结果表明:随着梁长度的增大,梁的固有频率逐渐减小,结构的损耗因子呈现先增大后减小的趋势,梁的长度存在最佳动力学设计值;增大阻尼层剪切模量,结构固有频率逐渐增大,结构的损耗因子呈现先增大后减小的趋势,阻尼层剪切模量也存在最佳动力学设计值;随阻尼层厚度的增大,结构的固有频率逐渐降低,一阶模态下的损耗因子逐渐增大,但是其余模态下的损耗因子呈现先变小后增大的规律;中间层损耗因子值对频率的影响不大。

The partial differential vibration equations of damping layer composite sandwich beam were deduced combined with the principle of Hamiltons Principle.Then,these vibration equations were solved by means of the closed-form Navier method,and the calculated result was validated versus the data of the published literature.Finally,the influence of changing parameters of the damping layer composite beam on its dynamic properties was studied.The results show that:The natural frequency decreases gradually and the loss factor tends to go from ascent to descent with the increase of length of beam,and there is an optimal value of length in the dynamics design.The natural frequency increases gradually and the loss factor tends to go from ascent to descent as the shear modulus of the damping layer is increased,and there is an optimal value of shear modulus in the dynamics design.With the increase of thickness of damping layer,the natural frequency decreases gradually,the first-order loss factor increases gradually and the other loss factors tend to go from descent to ascent.The loss factor of damping layer has less influence on the natural frequencies.