Forced convection in high porosity metal foams

This paper reports an experimental and numerical study of forced convection in high porosity (epsilon similar to0.89-0.97) metal foams. Experiments ha ve been conducted with aluminum metal foams in a variety of porosities and pore densities using air as the fluid medium. Nusselt number data has been obtained as a function of the pore Reynolds number. In the numerical study, a semi-empirical volume-averaged form of the governing equations is used. The velocity profile is obtained by adapting an exact solution to the momen tum equation. The energy transport is modeled without invoking the assumpti on of local thermal equilibrium. Models for the thermal dispersion conducti vity, k(d), and the interstitial heat transfer coefficient, h(sf), are post ulated based on physical arguments. The empirical constants in these models are determined yb matching the numerical results with the experimental dat a obtained in this study as well as those in the open literature. Excellent agreement is achieved in the entire range of the parameters studied, indic ating that the proposed treatment is sufficient to model forced convection in metal foams for most practical applications.