超声与固体中含气泡层的相互作用

INTERACTION OF ULTRASONIC WAVE WITH VOID- CONTAINING LAYER IN SOLID

本文利用固体层状媒质声反射模型,给出了固体中含气泡层声反射和透射系数的表达式,并由此导出沿固体中含气泡薄层对称和反对称模式界面波的特征方程式。本文还介绍了含气泡固体有效弹性模量的估算方法,文中给出的数值计算具体说明了气泡体积浓度和气泡层厚度对声反射系数、声透射系数以及反对称模式界面波传播速度的影响,本文的研究为根据声反射系数和界面波的传播速度的测量反演固体间气泡层的力学性能提供了理论依据。

Using a general model for sound reflection from multilayered media, we present in this paper the expressions for sound reflection and transmission coefficients on voidcontaining interface layer in solid and derive the characteristic equation for symmetric and antisymmetric modes of the interface waves along the layer. The method for evaluating the effective elasric moduli of void-containing solid is also introduced. The numerical calculation given in this paper shows the influence of the void volume concentration and layer thickness on the sound reflection coefficients and interface wave velocity, providing a theoretical basis for inverse deduction of the mechanical properties of void-containing layer based on ultrasonic measurements.