Pore-scale simulations, by explicitly incorporating the geometrical features of the porous medium, enable accurate examination of fluid flow and particle transport within the foam. The present study numerically investigates nanoparticle transport and deposition in open-cell metallic foams with Voronoi-based geometries and a fixed porosity of 80%. Foam structures were reconstructed using the Laguerre–Voronoi algorithm, and simulations were performed with an Eulerian–Lagrangian framework implemented in the open-source software OpenFOAM. The model accounts for drag, Brownian motion, gravity, buoyancy, and Saffman lift forces, as well as van der Waals and electrostatic double-layer interactions to capture nanoparticle–wall adhesion. Results indicate that increasing the pore density from 30 to 60 pores per inch (PPI) enlarges the interfacial area while reducing flow velocity, thereby extending particle residence time and significantly enhancing deposition. Quantitatively, this increase in pore density leads to an approximate 26.5% rise in nanoparticle deposition ratio. Among the cases examined, the Voronoi foam with 80% porosity and 30 PPI exhibited the lowest deposition rate, whereas the foam with 80% porosity and 60 PPI showed the highest.