基于信号时频分析理论识别时变模态参数的实验
Experimental Investigation on Estimation of Time-Varying Modal Parameters Using Time-Frequency Analysis

为研究温度对结构模态参数的影响设计了一套温度可控的实验设备。在这套实验设备提供的可控温度环境中采集悬臂梁结构的加速度响应信号，利用基于信号时频分析的模态参数辨识算法处理实验数据，得到其时变模态参数，包括固有频率和振型，以此研究温度对其模态参数的影响。分析结果显示了基于信号时频分析的模态参数辨识算法在处理非平稳信号以得到结构的时变模态参数上的应用前景，更重要的是实验数据的分析结果较好地反映了温度对结构模态参数的影响，为热环境下结构振动特性分析提供了可靠而且有价值的分析方法和实验依据。
To investigate the effect of varying temperature on the modes of structures, a set of experimental systems is designed to provide a temperature-controlled environment. An experiment is conducted on a TC-4 titanium alloy cantilever beam in a temperature-varying environment, and a modal parameter identification method based on time-frequency analysis (TFA) is applied to process the response signals of the beam to estimate time-varying modal parameters, including natural frequencies and mode shapes. The results show the future application of the TFA-based modal parameter identification method for the estimation of time-varying modal parameters. The results reveal the thermal effect on the modal parameters, thus providing a valuable signal-processing method for investigating the dynamical properties of structures in a temperature-varying environment.