基于小波分析的螺栓联接结构的动态特性分析  

Dynamic Characteristics Analysis of Bolted Joints Based on Wavelet Analysis

作　　者：闫航瑞[1] 曾国英[1] 赵登峰[1] 

机构地区：[1]西南科技大学制造科学与工程学院省部共建教育部重点实验室制造过程测试技术,绵阳621010

出　　处：《机械设计与制造》2012年第9期148-150,共3页Machinery Design & Manufacture

基　　金：国家自然科学基金-中国工程物理研究院联合资助资金项目(10876034)

摘　　要：利用小波包分析技术提取敲击状态下搭接梁螺栓联接结构包含某一固有频率的振动加速度信号,根据该频段信号的连续小波变换(CWT,1-D Continuous Wavelets)分析螺栓联接结构随着预紧力变化的动态特性。首先基于Premax大型数据采集与分析系统搭建实验平台;之后根据振动信号的时频特性选取(320～480)Hz作为分析频段并进行单支重构;然后对不同连接状况下在该频段的时域信号进行一维连续小波变换。分析结果发现螺栓松动变化与其结构的动态特性密切相关,在敲击下,预紧力越小,信号衰减越快,其结构阻尼越大,表示联接结构的能量耗散增大,系统非线性增强。Wavelet packet analysis is used to extract the acceleration signals of the bohedjoints struc- ture under the peening excitation which contains a natural frequency.The dynamic characteristics which change along with the bolt loose are analyzed by the frequency band signals of that CWT.The experimental system is built based on the Premax data acquisition and analysis equipment. Based on the time-frequency characteristic analysis of response signals ,the frequency bandwidth of （320-480）Hz is chosen as the analyzed frequency band and that is restructured Then, under different connection condition, the time-domain signals within the bandwidth of （320480）Hz are analyzed by the CWT.The result of the analysis shows that the looseness has a tremendous influence on the dynamic characteristics of the bolted joints structure in the peening vibrational environment, which is ,the smaller the pre loading, greater the structural damping, the more wave energy dissipation,with the faster the signal attenuation,and the nonlinear characteristics enhanced

关 键 词：敲击 振动信号 小波变换 动态特性 

分 类 号：TH16[机械工程—机械制造及自动化] V213.52[航空宇航科学与技术—航空宇航推进理论与工程]