剪切褶皱薄膜动态特性分析

Analysis of vibration behavior of shear wrinkling membrane

摘要:

基于拉格朗日方程建立了具有褶皱薄膜的振动微分方程,基于有限元程序建立了薄膜动态特性的分析流程,对矩形剪切薄膜后屈曲的动态特性进行分析.分析表明:矩形剪切薄膜后屈曲的振动模态与其褶皱构形具有很大的相关性,振动节线的位置处于褶皱波峰的位置,随着模态数的增加,其振动的节线数目依次减少,有更多的褶皱波峰处于振动状态,并且在薄膜的边缘出现了局部振动.随着剪切距离的增加,薄膜的褶皱幅度增大,其固有频率发生了振荡式变化,与薄膜屈曲前的固有频率相比,屈曲后的固有频率明显减小.

Abstract:

First,oscillatory differential equation with wrinkle membrane is established based on Lagrange equation and analysis flow of membrane dynamic characteristics is set up by FE program,and then post-buckling dynamic characteristics of rectangle shear membrane are studied.Results indicate that the post-buckling vibration modal of rectangle shear membrane has great correlation with wrinkle configuration.The position of vibration pitch line gets along with the position of wrinkle wave crest.With the increasing of mode number,the number of vibration pitch line is reduced sequentially,and more wrinkle waves crest at the state of vibration.At high order mode,local vibration is presented at the edge of membrane.As shear distance increased,the amplitude of membrane wrinkle is enlarged,and oscillatory variety takes place in natural frequency.The natural frequency is obviously reduced after buckling.