Pore-scale simulation of ultralight sandwich panel filled with metal foam for simultaneous load bearing and active cooling

This study employs pore-scale numerical simulations to investigate the thermal–hydraulic and mechanical (out-of-plane quasi-static compression) performances of three ultralightweight sandwich configurations: a corrugated-core sandwich structure (CSS), a CSS filled with smooth-surfaced metal foam (CSS–SMF), and a CSS filled with rough-surfaced metal foam (CSS–RMF). Simulation results for both the thermal–hydraulic and mechanical performance are compared with existing experimental measurements, with good agreements achieved. Results demonstrate that the CSS–RMF outperforms the CSS–SMF in heat transfer, owing to strong flow disturbances induced by micro-rods on foam ligament surfaces, which disrupt the thermal boundary layer and promote fluid mixing. Although the metal foam filling introduces additional flow resistance—the pressure drop per unit length increases by ∼25–35 times for the CSS–SMF and 38–58 times for the CSS–RMF—both configurations can still achieve net heat transfer gains under equal pumping power, or equal pressure drop, conditions, at moderate to high Reynolds numbers. Compared with the SMF, the RMF increases the volume-averaged Nusselt number by 29%–40% in laminar flow and 35%–48% in turbulent flow, attributable mainly to its 25%–35% larger specific surface area. Compression analyses further reveal that although the metal foam has limited load-bearing capacity on its own, it can enhance the mechanical performance of the hybrid sandwich structure by constraining web deformation during the strain-hardening stage, thereby increasing its peak stress and specific energy absorption. These findings support the design of lightweight multifunctional sandwich structures with improved thermal management and mechanical robustness.