Performance of Aluminum and Carbon Foams for Heat Transfer Augmentation

Abstract

The airside heat transfer performance of three aluminum foam samples and three modified carbon foam samples are examined for comparison. The aluminum foam samples have a bulk density of 216 kg/m3 with pore sizes of 0.5, 1, and 2 mm. The modified carbon foam samples have bulk densities of 283, 374, and 403 kg/m3 and machined flow passages of 4 mm in diameter. The samples were placed in a forced convection arrangement using a cartridge heater as the heat source and ambient air as the sink. A constant heat flux of 30.6 kW/m2 is applied throughout the experiments with the mean air velocity ranging from 1 to 9 m/s as the control parameter. The Brinkman extended Darcy momentum model and a two equation non-equilibrium heat transfer model are employed to extract the interstitial heat transfer coefficients. Pressure drop measurements are correlated with the Darcy-Forcheimer relation. Empirical heat transfer correlations for the aluminum and carbon foam samples are provided.