基于反射系数测量的黏弹性材料动态力学参数反演方法

Inversion analysis of viscoelastic material dynamic parameters based on reflection coefficient measurement

提出一种通过测量声学覆盖层的反射系数,并反演黏弹性材料动态力学参数的方法。分别测量圆柱空腔覆盖层在两种不同背衬条件下的反射系数,根据圆柱空腔覆盖层反射系数与其材料动态力学参数之间的解析关系,利用二元非线性方程组求根的牛顿迭代法,求解方程组可以获得黏弹性材料的复纵波声速和复剪切波声速,进而计算复杨氏模量和复泊松比等其它黏弹性动态力学参数。最后,对某种橡胶材料进行了声管测试,并对黏弹性动态力学参数的测量结果进行了分析和讨论。

Based on measuring the reltecuon coefficient,of an acoustic layer, the inversion analysis procedure of viscoelastic material＇s dynamic parameters was developed. In order to get two different reflection coefficients, the reflection coefficient of a cylindrical-hole acoustic layer with two different backings was measured for two times. According to the analytical relationship between the reflection coefficient and the dynamic parameters of the acoustic layer, using Newton＇s iteration method for nonlinear equations of two variables, the complex longitudinal wave speed and the complex shear wave speed were obtained by solving a group of equations. Furthermore, the complex Young＇s modulus and the complex Poisson＇s ratio were calculated easily. Finally, a rubber sample was tested in a acoustic-pipe, and the identification results of viscoelastic material dynamic parameters were analyzed and discussed.