Aluminium Foams For Heat transfer Applications

Open cell metal foams show great potential as a heat exchangers, due to their permeability to fluids and the high conductivity of the metallic network. In this study, aluminium foams were produced using the replication technique with NaCl, flour and water used to create the preform. The samples produced included both uniform pore sizes and examples where different pore sizes were created in different parts of the sample as well as these, samples made commercially by a similar technique (Corevo foams) and by an investment casting process (Duocel foams) were examined. A bespoke rig was designed, built and used to measure the thermal and fluid flow performance of all foams being investigated under forced convection conditions. Results for heat transfer coefficient and pressure drop across the sample with the comparison between each type of sample are presented. It was found that all the foams tested can have favourable heat transfer behaviour under certain conditions asymmetric behaviour can be obtained when non-uniform pore sizes are present; a factor that could be exploited in heat exchanger design.