密集频率成分自由衰减振动响应信号解耦方法  

Decomposition of Damped Free Vibration Signals with Close Natural Frequencies

作　　者：张万良[1] 李舜酩[1] 廖庆斌[1] 

机构地区：[1]南京航空航天大学能源与动力学院,南京210016

出　　处：《振动．测试与诊断》2008年第2期87-90,共4页Journal of Vibration,Measurement & Diagnosis

基　　金：国家自然科学基金资助项目(编号:50675099)

摘　　要：基于单一频率成分的自由衰减振动响应信号的相关性原理,提出了一种频率密集成分的两耦合振子自由衰减振动响应信号的解耦算法。通过对模拟的两耦合振子密集频率成分的自由衰减振动响应信号进行解耦,验证了此算法的正确性和有效性。仿真实例研究发现,整体解耦精度随采样频率的增大及两特征信号相对频率间隔的增大而显著提高。当无噪声干扰(或噪声干扰很小)时,该方法的解耦精度很高;当有强噪声干扰时,该方法对频率密集成分的两耦合振子自由衰减振动响应信号的解耦仍有一定的精度。Based on the correlation principle,an algorithm to decomposite the damped free vibration signals of a two degrees of freedom system with close natural frequencies is put forward.The validity of the method is proved by numerical simulation.The results show that the accuracy of a decomposed solution,in general,can be improved by increasing either the sampling frequency or the interval between two natural frequencies.The results also show that the noise of measurement has the influence on the solution,the higher the noise level,the lower the accuracy.

关 键 词：自由衰减振动 密集频率 相关函数 解耦 

分 类 号：TP911[自动化与计算机技术] O321[理学—一般力学与力学基础]