Abstract:

The low thermal conductivity for most of phase change materials is one of main obstacles in real application. Foam metals can be added into the phase change material to strength heat transfer process because of high thermal conductivity, high porosity and high specific surface area of foam metals. Based on the 3D W-P micro structure model of foam metal, the effect of porosity and pore diameter of foam metals on effective thermal conductivity of the foam metal based composite phase change materials were analyzed. The numerical simulation method was used to predict the thermal conductivity of foam aluminum-air and foam aluminum-water composites.The results show that the W-P model can be used to precisely predict the thermal conductivity of foam metals. The effective thermal conductivity of foam copper-paraffin composite was then analyzed. It is shown that the thermal conductivity of phase change material can be enhanced greatly by adding foam metals, and the thermal conductivity of paraffin has been increased 13 times when the porosity of foam copper is 97.57%. This study has reference value for thermophysical properties enhancement research on phase change materials.

Key words: foam metal, phase change thermal energy storage, effective thermal conductivity, heat transfer enhancement