Modeling Acoustic Properties of the Fluid-Fluid Interface in Porous Medium

Abstract

The purpose of this study is to present mathematical modeling of the acoustic properties of fluid-fluid interface in porous medium in order to to identify fluid-fluid interfaces according to their different acoustic properties. Biot's theory of acoustic wave’s propagation inhomogenous porous medium is used to calculate reflection and transmission coefficients of an interface in the porous medium. It is found that these coefficients are sensitive to the frequency and the angle of the incident wave, which is regarded as the significant acoustic property of fluid-fluid interfaces an d of discontinuities of the porous medium. Acoustic properties of general fluid-fluid interfaces or porous medium discontinuities are presented as series of plots of coefficient magnitude versus incident frequency or angle. It is shown that there is significant acoustic difference between a fluid-fluid interface and a discontinuity of the porous medium, which can be used to identify a fluid-fluid interface. Here, methods are designed to locate, identify a fluid-fluid interface, and measure its shape, using reflection and/or transmission of waves.

Keywords: sonar probing, modeling acoustic properties of interfaces, Biot’s theory, computer simulation