A fractal-skeleton model of high porosity macroporous aluminum and its heat transfer characterizes

Macroporous metal foams are used as energy exchange materials and have been widely used in the industry. In this paper, the finite element method is used to calculate the equivalent thermal radiation conductivity and equivalent thermal conduction equivalent conductivity of the fractal-skeleton heat transfer model, and the heat transfer characteristics of the two components are analyzed. The results show that during thermal conduction progress, energy transfer mainly occurs at the junction of walls and holes perpendicular to the direction of heat flow. While during the thermal radiation process, the smaller the cell wall thickness and the larger the porosity, the larger the proportion of the heat radiation conductivity in the total heat conductivity. When the structural size is equal to the characteristic wavelength, the scattering coefficient is rapidly reduced, so that the radiation heat transfer effect is improved. Finally, the cause of this phenomenon is further explained by the micro-mechanism theory.