Forced Convection in High Porosity Metal Foams

TLDR

This paper reports an experimental and numerical study of forced convection in high‑porosity (ε≈0.89–0.97) metal foams. Experiments were conducted on aluminum foams of varying porosity and pore density with air, and a semi‑empirical volume‑averaged model was developed that uses an exact solution for the velocity profile, non‑LTE energy transport, and physically based models for thermal dispersion conductivity and interstitial heat transfer, with empirical constants calibrated against experimental data. Excellent agreement was achieved across the studied parameter range, indicating the proposed treatment is sufficient to model forced convection in metal foams for most practical applications. Article identifier: S0022-1481(00)01903-4.

Abstract

This paper reports an experimental and numerical study of forced convection in high porosity (ε∼0.89–0.97) metal foams. Experiments have 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 momentum equation. The energy transport is modeled without invoking the assumption of local thermal equilibrium. Models for the thermal dispersion conductivity, kd, and the interstitial heat transfer coefficient, hsf, are postulated based on physical arguments. The empirical constants in these models are determined by matching the numerical results with the experimental data obtained in this study as well as those in the open literature. Excellent agreement is achieved in the entire range of the parameters studied, indicating that the proposed treatment is sufficient to model forced convection in metal foams for most practical applications. [S0022-1481(00)01903-4]