The study of the mechanical behavior of porous materials and the understanding of damage mechanisms are key elements for designing metal structures. In ductile materials, fracture is governed by the nucleation, growth and interactions of voids which, ultimately, coalesce leading to macroscopic failure. Micromechanical models developed for dynamic loading conditions (e.g., Molinari and Mercier [1]) have highlighted the significant influence of local accelerations of material particles on the mechanical behavior and fracture of ductile materials. These micro-inertia effects, particularly marked near pore boundaries, have been extensively investigated in recent years (e.g., El Ansi et al. [2]). It is important to note that most micromechanical approaches developed in this field rely on the definition of a representative volume element (RVE) containing a single void characterized by a unique size and geometry. However, few studies have explored the dynamic response of porous materials when void size heterogeneities come into play. In this study, we adopt an RVE containing voids of varying sizes to investigate the dynamic behavior of porous materials [2]. A finite element model, subjected to high strain rate spherical loading, is proposed to analyze void-void interactions. The model consists of a stacked arrangement of two distinct cubic unit cells, each embedding a spherical void of different radius. Numerical results highlight the impact of void interactions on the local velocity field, which modulates the dynamic macroscopic response. Based on these findings, we propose a new dynamic multiscale modeling approach that involves an interaction parameter to characterize void interaction effects. Additionally, we examine the influence of void spatial distribution on the macroscopic response. [1] Molinari A., Mercier S., Micromechanical modelling of porous materials under dynamic loading, Journal of the mechanics and Physics of Solids 49, (2001), p 1497-1516. https://doi.org/10.1016/S0022-5096(01)00003-5 [2] El Ansi M., Sartori C., Czarnota C., Analysis of the mechanical behavior of porous material containing two populations of voids under dynamic spherical loadings, Mechanics of Materials 198, (2024), 105112. https://doi.org/10.1016/j.mechmat.2024.105112