On the Efficiency of Air-Cooled Metal Foam Heat Exchangers

This study analyses the heat transfer performance of metal foam heat exchangers through experimental measurements. Using counter-gravity infiltration casting, open-cell aluminium foam elements were manufactured to embed a copper tube for internal mass flow containment. Heat transfer experiments were conducted under natural and forced convection conditions, with the airflow controlled in a wind tunnel. A stream of warm water within the internal foam component served as the heat source, transferring thermal energy to the surrounding air flowing through the external foam component of the heat exchanger. The results showed a significantly enhanced heat transfer performance with aluminium foam compared to a single copper tube. Thermal resistance models were developed to elucidate the heat transfer mechanisms, highlighting the effectiveness of air-cooled metal foam heat exchangers. These findings underscore the potential of metal foam heat exchangers as cost-effective alternatives for various thermal management applications.