ABSTRACT

The large scale behavior of heterogeneous media undergoing acoustic excitations is approached using the method of multiple scale asymptotic developments. This process leads to the macroscopic equivalent behavior and introduces effective coefficients and averages of microphysical quantities, without imposing any prerequisite at the macroscopic scale. The acoustics of three classes of materials are studied, i.e., elastic composites, saturated deformable porous media with single or double porosity, mixtures of liquids. In each investigated case the domain of validity of the macroscopic equivalent description is made precise. Domains where such a macroscopic description is not possible are pointed out.