准确求解固有频率提高分段积分阻尼识别精度及其应用  

Improvement of the Accuracy of Damping Identification by using Piecewise Integral based on Accurately Solving the Natural Frequency

作　　者：时海涛 程惠 赵晓丹[1] SHI Haitao;CHENG Hui;ZHAO Xiaodan(School of Automobile and Traffic Engineering,Jiangsu University,Zhenjiang 212013,Jiangsu China)

机构地区：[1]江苏大学汽车与交通工程学院

出　　处：《噪声与振动控制》2019年第3期83-87,共5页Noise and Vibration Control

基　　金：拖拉机动力系统国家重点实验室开放基金资助项目(SKT2016013);江苏省高校优势学科建设工程资助项目(PAPD)

摘　　要：分段积分法是一种新近提出的阻尼识别方法,该方法的关键是需要准确识别信号固有频率。提出一种求解振动衰减信号有阻尼固有频率的方法,先使用傅里叶变换初估信号固有频率,通过两次积分运算构造出关于固有频率误差的方程组,解方程推导出计算公式,求得准确的信号固有频率,进而将其用于分段积分法识别阻尼。算例表明,该方法能够准确快速求解固有频率,通过控制整周期积分提高了阻尼识别精度,并且有益于准确计算出信号的幅值和相位,使得整个阻尼信号的识别和提取更加准确。将此方法应用于发动机齿轮室盖的阻尼识别,结果准确。Piecewise integration is a recently proposed method for damping identification.The key of this method is to accurately identify the natural frequency of the signal.In this paper,a method of solving the natural frequency is proposed.Firstly,the natural frequency of the signal is estimated using Fourier transform.The equations of natural frequency error are constructed through twice integral operations.Then,the equations are solved and the exact natural frequency of the signal is obtained.Then,the natural frequency is used to identify the damping by piecewise integral method.The example shows that this method can solve the natural frequency accurately and quickly,raise the accuracy of damping identification by controlling the whole period integral,and is beneficial to the accurate calculation of the amplitude and phase of the signal.As a result,the whole damping signal can be identified and extracted more accurately.Finally,the proposed method is applied to damping identification for the gear housing cover of an engine.

关 键 词：振动与波 信号识别 固有频率 阻尼比 齿轮室盖 

分 类 号：O321[理学—一般力学与力学基础] TN911.7[理学—力学]