The Effective Thermal Conductivity of Composite Phase Change Materials with Open-Cellular Metal Foams

Due to their high thermal conductivity, open-cellular metal foams are frequently used to improve the thermal conductivity of phase change materials. In this paper, the effective thermal conductivity of open-cellular foam filled with PCM with cubic units containing 12 solid tubular ribs was determined using an effective medium theory for composites. It was shown that metal foams with a large ratio of the radius of the tubular rib to its length can reach higher thermal conductivity. The case was also analyzed when the surface of the foam ribs was covered with a thin layer of another metal with high thermal conductivity. The results predicted by the proposed model were compared with the theoretical results of other models and with experimental data for some metal foam filled with phase change materials. A good agreement was achieved between present model predictions and experimental data.