Comparison of numerical and effective-medium modeling of porosity in layered media

In this study, modeling approaches for porosity in layered media are presented and compared. First, an effective-medium model is used to account for the frequency-dependent attenuation of the elastic waves. The effective-medium model is based on a single-scattering approach, i.e, it neglects multiple-scattering effects. Then, the effective-medium model is compared in time-domain finite element simulations. The numerical model allows the study of the scattering of the elastic waves on randomly distributed spherical cavities and also accounts for multiple-scattering effects. The models are compared to investigate the validity of the effective-medium model approach. The calculated reflected laminate responses and transmission spectra from the two models show a good agreement.