轴向运动梁的激励功率谱辨识  

Identification of Excitation Power Spectrum Density of an Axially Moving Beam

作　　者：刘涛[1] 吴炜[2] 史济涛[2] 蔡国平[1] 

机构地区：[1]上海交通大学工程力学系,海洋工程国家重点实验室,上海200240 [2]中国空空导弹研究院,河南洛阳471009

出　　处：《航空兵器》2014年第4期45-48,66,共5页Aero Weaponry

基　　金：国家自然科学基金(11132001;11272202);航空科学基金(20120157002);博士点基金(20110073110008);上海市教委科研重点项目(14ZZ021)

摘　　要：以轴向运动柔性梁为对象,采用Hamilton原理建立了轴向运动柔性梁的运动微分方程,采用复模态分析方法推导了两端简支梁和两端自由梁边界条件下的系统固有频率方程,采用Ritz法对系统运动微分方程离散化,进行系统在外激励作用下的响应分析,并在频域空间导出了随机外部激励的功率谱与系统响应的功率谱之间的转换关系,开展了激励功率谱的辨识工作。仿真结果表明,本文所给方法能够有效地对外部激励的功率谱进行辨识。The identification of excitation power spectrum density （ PSD） of an axially moving beam is investigated .The dynamic differential equation of an axially moving beam is established by Hamilton princi -ple.With the complex modal analysis method , the frequency equations of the simple and freely supported beams are deduced respectively .The Ritz method is utilized to discretize the dynamic equation of the system and is used to calculate the system response under external excitation .Based on the discrete model , the transforming relationship of power spectrum density between external excitation and system response is de -duced in the frequency domain space , and is used to obtain the PSD identification of external excitation . Simulation results show that the presented method is effective in identifying the PSD of external excitation .

关 键 词：轴向运动梁 功率谱辨识 复模态分析 RITZ法 随机激励 

分 类 号：O326[理学—一般力学与力学基础] TB123[理学—力学]