Theory of wave propagation and dispersion in fluid-saturated porous media allowing for spatial dispersion

This paper is concerned with long-wavelength sound propagation in rigid-framed fluid-saturated porous media. For unbounded macroscopically homogeneous media, isotropic or having a preferred `waveguide' axis, the symmetry of the problem suggests that the wave propagation should be described in terms of an Equivalent-fluid having frequency- and wavenumber-dependent density and bulk modulus. A definite procedure is proposed here, which allows performing the nonlocal homogenization of the properties of the `waveguide' medium, i.e. computing in principle from microstructure the effective density and effective bulk modulus.