Reflection and transmission of acoustic wave on multilayered porous media

Based on the Biot theory of sound propagation in fluid-saturated porous medium we have studied in this paper the sound reflection and transmission on multilayered porous media, in which the adequate boundary conditions across interfaces are taken into account. Numerical calculation of the reflection and transmission coefficients at different incident angles and frequencies of the fast compressional wave incident on porous media with three layers are presented. The results indicate that the maxmum or minimum reflection and transmission coefficients appear when the ratio of the wavelength to the thickness equals to certain valus the sound incident angle and porous media properties are shown to give great influence on these coefficients.