Investigation of heat transfer improvement at idealized microcellular scale for metal foam incorporated with paraffin

In this work, a microcellular model is developed to study the thermal behavior of a plate constituted of paraffin impregnated in metal foam. A three-dimensional model is considered using the finite elements method (FEM) with a body centered cubic (BCC) shape as a geometric configuration. COMSOL Multiphysics software is used to build the geometry and to conduct the calculation. The effects of porosity on the effective thermal conductivity, as well as on the thermal management performance of the composite plate are investigated. The model is calibrated using experimental data obtained in-situ. The results are found in good agreement with the experimental data from the literature. The decrease in the porosity results in an increase in the effective thermal conductivity of the metal foam, which makes the heat diffusion in the composite material faster than that in pure paraffin. Due to the contact surface between the metal foam and paraffin which is large in this case, it is found that a small pore diameter uniforms well the melting front and the temperature inside the composite.