约束阻尼板结构模态实验及阻尼特性研究

Modal Experiment and Damping Characteristics Analysis of Constrained Damping Plates

约束阻尼结构可在较宽的频带范围内抑制结构振动,已在机械和交通等领域得到广泛应用。采用多输入多输出(MIMO)的锤击法,对一种约束阻尼板进行模态实验,通过参数识别得到其固有频率、振型及模态阻尼。通过模态实验和有限元结果的相互对比,验证了模态测试结果的可靠性。在此基础上,对敷设黏弹性阻尼的悬臂板结构进行阻尼特性研究,讨论材料参数和结构参数对模态阻尼的影响,可为结构的减振降噪及优化设计提供依据。

Constrained damping structure can suppress vibration of the structure in a wide frequency band, and has been widely used in mechanical and traffic fields. In this paper, the modal experiment of a constrained damping plate was carried out by the hammering excitation with the multiple input and multiple output （MIMO） method. The natural frequencies, mode shapes and modal damping ratio were obtained by parameter identification. The reliability of the modal experiment results was verified by comparing the modal test results with the finite element results. On this basis, damping characteristics of a cantilever plate structure with viscoelastic damping layer were studied and the effects of material parameters and structural parameters on modal damping were discussed. This study provides a reference for the vibration and noise reduction and optimization design of structures.