机敏约束层阻尼薄板有限元建模与实验研究

Finite Element Modeling and Experiment Research of Smart Constrained Layer Damping Thin Plate

基于Kichhoff薄板理论,考虑基层、粘弹性层和压电层的耦合运动及位移协调关系,采用有限元法建立了机敏约束层阻尼结构的单元动力学方程。在单元组集后的系统总动力学方程中将基层的弹性结构阻尼以比例阻尼的形式给出,同时为表征粘弹性材料随温度、频率变化的力学特性,结合GHM(GollaHughes-Mctavish)模型推导出了结构的有限元总动力学分析方程。以局部覆盖机敏约束层阻尼的对边固支板铝板为实例,通过动力学参数理论计算与模态试验对比分析,结果表明:考虑基层阻尼后的分析结果明显好于不考虑基层阻尼的分析结果,与实验更接近;在总动力学方程中引入GHM模型,可以用相对较少的耗散自由度得到较准确的有限元动力学模型,减少了计算工作量。

Considering the coupled motion and displacement coordination relationship of basic layer,viscoelastic layer and piezoelectric layer,we establish the dynamic equations of plate with smart constrained layer damping based on the Kirchhoff thin plate theory. The elastic structure damping of basic layer was taken into account using proportional damping,and the global dynamic analysis equations of finite element was established based GollaHughes-Mctavish（ GHM） model to represent the mechanical characterization of viscoelastic materials varying with temperature and frequency. The comparison of theoretical calculation and modal experiments for kinetic parameters was conducted with the examples of clamped-clamped plate with partially treated smart constrained layer damping.The results show that the analysis results considering basic layer damping are closer to the experiment,significantly better than the results without considering basic layer damping. The finite element dynamic model can be obtained accurately by lesser dissipation of degrees of freedom using the method of introducing GHM model in global dynamic equations,and the computation cost can also be reduced.