Heat transfer performance of Aluminum foams during single phase air flow

This paper presents the experimental heat transfer and pressure drops measurements relative to single phase air flow through two different Aluminum foams, electrically heated. Because of their interesting heat transfer and mechanical properties, metal foams have been proposed for several different applications both thermal and structural. The tested Aluminum foams present 5 and 40 pores per inch (PPI) respectively and they have been inserted in a new test equipment located at the Department of Fisica Tecnica of the University of Padova. The experimental heat transfer coefficients and pressure drops have been collected by varying the air mass flow rate and the electrical power which has been set at 25.0, 32.5 and 40.0 kW m2. This paper aims to point out the effective thermal fluid dynamic behaviour of these new enhanced surfaces which present high heat transfer area per unit of volume at the expense of high pressure drop. Moreover, the results of several semi-empirical correlations for pressure gradient calculation have been compared with the collected experimental data points.