Electromagnetic field excitation during the scattering of an acoustic wave on an inhomogeneity in a poroelastic medium Academic Article in Scopus uri icon

abstract

  • © 2022 Elsevier LtdElastic wave propagation in porous media containing a movable fluid is frequently accompanied by electromagnetic field generation. Such field can be produced, for instance, by piezoelectric effect or have electrokinetic origin. In the present work, we consider the case of electrolyte-filled pores; thus, the generated electromagnetic field is associated with the electrokinetic effects. In this case, the magnitude of the electric current generated by the elastic wave is proportional to the magnitude of the relative displacement in the fluid and the solid phases. The presence of inhomogeneities in a porous medium can result in appearance of additional fluid flow with respect to the solid phase; thus, an additional electric field is generated. In our work, the magnitude of the electromagnetic field generated during the scattering of an elastic wave on a spherical porous inclusion in a porous matrix is calculated. The inclusion can differ from the matrix by the properties of the fluid in the pores or the properties of the elastic skeleton, such as porosity or permeability. The solution of the dynamic equations of electrokinetics is obtained by using the hypothesis that the inclusion size is much larger than the characteristic size of the pores. We have obtained the dependencies of the amplitude of the generated electromagnetic field on the inclusion parameters and the incident wave frequency. It was shown that the analysis of the additional electromagnetic field generated during the scattering of the elastic wave can provide some useful information about the structure of porous media.

publication date

  • January 1, 2023