局部约束阻尼开口柱壳的减振分析及优化

为了缩减开口柱壳结构的振动,本文基于Lagrange方程以及Sanders薄壳理论建立了局部约束阻尼开口柱壳的动力学模型,分析了粘弹性单元分段数和厚度、阻尼单元占空比以及约束层敷设角和厚度对结构前三阶模态损耗因子和固有频率的影响,得到了各参数对结构振动特性的影响规律。并以前三阶损耗因子为目标,应用NSGA-II遗传算法对约束阻尼柱壳进行了多目标优化,对比分析了优化前后约束阻尼结构的频域特性。结果表明,约束阻尼结构的参数对开口柱壳减振特性具有重要影响,通过对约束阻尼结构的优化,可以在引入较小约束阻尼质量的基础上,有效提升结构减振效果。

Analysis of vibration reduction and optimization for open cylindrical shell with local constrained layer damping

In order to reduce the vibration of open cylindrical shells,based on the theory of Sanders shell and Lagrange equation,a dynamics model of an open cylindrical shell with local constrained layer damping is established in this paper.The influences of the element number and thickness of viscoelastic element segments,duty ratio of damping element,laying angle and thickness of constrained layer on the loss factors and natural frequencies of the first three modes are analyzed.The effect of the parameters is obtained on the vibration characteristics of the structure.In addition,with the first three order modal loss factors as the objective,the NSGA-II genetic algorithm was used to optimize the cylindrical shell with constrained layer damping.The frequency domain characteristics of the structure with local constrained layer damping before and after optimization are analyzed.The results show that the structure parameters of the constrained layer damping have an important influence on the vibration reduction of the open cylindrical shell.And through optimization,the vibration reduction of the open cylindrical shell can be effectively improved on the condition of introducing lower mass of constrained layer damping.