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arXiv · 2508.15340

Discovering correlations between metal foam thermal characteristics and non-Fourier behavior

Abstract

Due to their low density and large specific surface area, metal foams are increasingly used as cellular materials that combine excellent structural and thermal properties. Their cellular structure makes them particularly suitable for use in heat exchangers, insulation, and fire protection layers. The heat transport that takes place within them is a complex phenomenon characterized by the simultaneous presence of heat conduction, heat transfer, and heat radiation, making their modeling a significant challenge. The aim of the research is to develop a one-dimensional, time-dependent, discrete numerical model capable of describing the effective thermal behavior of metal foams. The model takes into account heat conduction through the solid phase, conductive heat transfer in the closed cavities, thermal radiation between the pore walls, and by-passing heat conduction around the cavity. The results highlight that geometric features such as cavity size and arrangement have a significant impact on temperature distribution and confirm that classical Fourier-based models are not accurately applicable to porous materials, but the Guyer--Krumhansl equation is an adequate candidate. Furthermore, we correlated the static and dynamic thermal diffusivity with the metal foam parameters, showing a significant sensitivity to the cavity thermal attributes.

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Anna Fehér, Dániel Cseh, Róbert Kovács. 2025-08-21. Discovering correlations between metal foam thermal characteristics and non-Fourier behavior. https://arxiv.org/abs/2508.15340

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