粘弹性材料阻抗非局域特性实验验证

Experimental validation of non-local property of impedance of viscoelastic material

基于材料透射阻抗的定义阐述了粘弹性材料的局域和非局域性质,并阐述了阻抗矩阵和频响函数矩阵之间的关系.通过将声压表面力的分布离散为等效点力的方法导出了频响函数表达式.基于频响函数矩阵元素的表达式,对粘弹性材料平板进行了点力激振下振动透射的频响测量实验,同时用粘弹性有限元方法数值计算了该板的振动频率响应,实验和数值结果的一致不但验证了粘弹性材料频率响应和声阻抗的非局域特性,也说明了实验及数值方法的正确,为进一步研究打下基础.

Based on the definition of transmission impedance the local and non-local properties of viscoe- lastic material and the relationships between the impedance matrix and the frequency response matrix were de- scribed. The expression of frequency response function was derived by discretizing the acoustic pressure to e- quivalent node force on the surface. Based on the formula of the response function the transmission frequency response experiment was carried out when a node force acted on a viscoelastic plate. The frequency response function of the viscoelastic plate was also got by numerical method on the basis of viscoelastic dynamic finite element. The non-local properties and the experimental and numerical approaches were validated by the com- parison of the two results, and these approaches can be used for other researches.