摘要
为了准确识别频率响应函数不一致情况下的模态模型,建立了一种模态参数估计的最小二乘复频域局部求解新方法。以轻质板为例,在传感器质量过大导致频响函数不一致时,利用最小二乘复频域法的整体求解和局部求解两种方法分别识别了其模态模型。对比两者的结果可见:相比于整体求解方法,采用局部求解方法获得的轻质板模态频率与标准试验误差很小,自由状态下的模态振型与理论振型亦相一致,表明最小二乘复频域局部求解方法在频响函数不一致的情况下能够准确识别模态模型。
In order to accurately identify the modal model based on inconsistent frequency response functions（ FRFs）,a new local solving method for modal parameters estimation in the least square complex frequency（ LSCF） domain is proposed. Taking a light mass plate as an example,considering the inconsistent FRFs caused by the added mass of transducers,we estimate the modal based on LSCF utilizing the global solving method and local solving method,respectively. The comparison of results show that the natural frequencies obtained by the local solving method have smaller errors than these of the standard test,and the modal shapes are consistent with the theoretical ones. It demonstrates that the local solving method based on LSCF can accurately identify the modal model based on inconsistent FRFs.
出处
《机械科学与技术》
CSCD
北大核心
2016年第1期35-39,共5页
Mechanical Science and Technology for Aerospace Engineering
基金
国家自然科学基金项目(51275542)资助
关键词
模态分析
参数估计
频率响应函数
局部求解
整体求解
actuators
design of experiments
eigenvalues and eigenfunctions
errors
frequency domain analysis
least squares approximations
mathematical models
MATLAB
matrix algebra
modal analysis
natural frequencies
parameter estimation
sensors
vectors
frequency response function
global solving method
local solving mehtod
