Compact Aluminium Foam Heat Exchangers

The aim of this study was to investigate the potential application of metal foams in shell-tube recuperators. A356 aluminium foam was cast around the internal and external surfaces of a thin-walled copper tube to enhance heat transfer between separated water streams at different temperatures. The results demonstrated that the aluminium foam drastically increased heat transfer efficiency due to its large volumetric surface area and high thermal conductivity. In the shell-tube foam recuperators, a maximum heat transfer efficiency of 48.1% was observed, compared to only 12.2% for a single copper tube without metal foam. The pressure drop across the external foam increased with the flow rate, from an average value of 1.19 kPa at 1.0 L/min to 7.36 kPa at 3.0 L/min. These findings suggest that metal foams have great potential for use in shell-tube recuperators, which could significantly improve the efficiency of heat transfer in various industrial and engineering applications.