一种周期结构隔振器力学性能研究

设计了一种由弹性片和支撑柱组成的小体积高刚度新型周期结构金属隔振器.首先利用微机控制电子试验机对其进行静力加载试验,得到静载下载荷-位移特性曲线.基于有限单元法,建立周期结构有限元模型,并以和试验相同的工况进行静力学分析,仿真和试验结果吻合良好.在此基础上研究了各主要尺寸参数对刚度的影响,结果表明,弹性片厚度对刚度影响较大,弹性片内径和层数对刚度影响较小.最后通过将周期结构隔振器等效为多自由度弹簧-质量模型,应用模态叠加法建立了动力学方程并推导出了力传递表达式,通过有限元进行了仿真对比并进行了试验验证.结果表明,理论和仿真匹配良好,且当承载质量超过一定值后,即可将周期结构简化为单自由度处理.

Study on Mechanical Properties of A Periodic Structure Vibration Isolator

A small volume and high stiffness periodic metal isolator composed of elastic plates and supporting columns is designed. Firstly, the static load test is carried out by using microcomputer controlled electronic testing machine, and the load-displacement characteristic curve is obtained. Based on the finite element method, a finite element model of periodic structure is established, and the static analysis is carried out under the same working conditions as the test. On this basis, the influence of the main dimension parameters on the stiffness is studied. The results show that the thickness of elastic sheet has great influence on the stiffness, while the inner diameter and the number of layers have little influence on the stiffness. Finally, by using the equivalent spring-mass model of the periodic structure isolator with multiple degrees of freedom, its dynamic equation is established by means of modal superposition method, and the expression of force transfer rate is deduced. A simulation is carried out based on the finite element analysis which is verified by experiment. The results show that the theory and simulation match well. When the load mass exceeds a certain value, the periodic structure can be simplified to single degree of freedom.