同步辐射光学元件的粘弹性减振方法  

A viscoelastic vibration reduction method of optical-elements for synchrotron radiation

作　　者：曹刚 李毅[1,2] 梁好 盛伟繁[1] CAO Gang;LI Yi;LIANG Hao;SHENG Weifan(Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院高能物理研究所,北京100049 [2]中国科学院大学,北京100049

出　　处：《核技术》2019年第12期1-7,共7页Nuclear Techniques

基　　金：国家自然科学基金(No.11905243)资助~~

摘　　要：同步辐射光束线光学元件的振动不稳定性将影响样品处的光斑位置,将粘弹性减振器安装在光学元件上可以减弱地面微振动对机构影响。研究设计了粘弹性减振器,对粘弹性材料的剪切储能模量和损耗模量进行共享参数的非线性拟合,得到Prony级数各项系数;通过有限元软件模拟了粘弹性减振器的动力学性能,并以某长反射镜为例,对安装减振器后的结构系统进行谐响应分析、瞬态动力学分析以及静力学分析,并且比较了减振器安装位置对减振效果的影响。结果表明:粘弹性减振器能有效控制地面微振动对光学元件长反射镜振动稳定性的影响;减振器安装在光学元件底板下靠近两端减振效果更好,能显著提高元件的振动稳定性。该项研究对光束线其他光学元件的振动稳定性研究具有参考意义。[Background]Vibration instability of optical-elements caused by ground micro-vibrations affects the position and focal length of the sample in the synchrotron beamline.[Purpose]This study aims to propose a scheme of employing viscoelastic dampers on beamline optical-elements for vibration reduction.[Methods]First of all,a viscoelastic damper was designed,and the coefficients of Prony series were obtained by nonlinear fitting of shear storage modulus and loss modulus of the viscoelastic materials by shared-parameters mode.Then,the dynamic properties of viscoelastic dampers were simulated by finite element software.Finally,this damper was applied to a long reflecting-mirror,and the harmonic response,transient dynamic analysis,and the static structural analysis of the supporting structure were carried out.In addition,the influence of the installation position of dampers on the damping effect were compared.[Results]Simulation results show that for the 1 mm vertical steady-state sweep excitation,the vertical displacement transmissibility of the mirror decreased by 35.2%(original position),53.7%(closer to the edges),32.4%(closer to the center)in the frequency range of 0~200 Hz,respectively.For the 1μm vertical half-sine shock excitation with duration of 6.25μs,the RMS values of 0.5 s after impact interference decreased by 70.8%(original position),79%(closer to the edges),59.7%(closer to the center),respectively.[Conclusions]The proposed viscoelastic damper can effectively reduce the influence of ground induced micro-vibrations on the mirror,and provide some guidelines for the vibration stability study of other optical-elements in synchrotron beamlines.

关 键 词：微振动 粘弹性减振器 非线性拟合 有限元分析 

分 类 号：TL99[核科学技术—核技术及应用]