利用PVDF阵列测量结构曲率模态的实验

摘要

提出利用PVDF阵列直接测量结构曲率模态。在振动梁表面均匀布置一组PVDF压电薄膜，测量结构在外加点激励作用下的动态响应，得到频率响应函数，进而通过模态软件对数据进行分析，得到其曲率模态。数值分析和实验结果表明：利用PVDF阵列可以有效地测量得到结构的曲率模态，且方法与激励力位置无关。由于方法操作简便， PVDF压电薄膜附加质量可忽略不计，与常规通过模态振型计算曲率模态的方法相比具有明显优越性。%With an example of a clamped beam, a direct method for measuring the curvature modal shape of structures by using PVDF array is presented. An array of rectangular PVDF films is uniformly attached to the surface of the beam as sensors for measuring the frequency response functions of the structure due to the external excitation. By using the modal analysis software to analyze the measurement data, the curvature modal shape of the beam can be obtained, which is then compared with the result from the numerical calculation of the modal shape. Experimental and numerical results show that the method has a good effect for measuring the curvature modal shape of structures. It has the advantages that it is easy to operate and independent of the excitation locations, the additional mass is negligible and so on.