Forced-Convection Measurements in the Fully Developed and Exit Regions of Open-Cell Metal Foam

Abstract

Experimental heat transfer data for water flow in commercial, open-cell-aluminum-foam cylinder heated at the wall by a constant heat flux, are presented. The measurements include wall temperature along flow direction as well as average inlet and outlet temperatures of the water. Flow speeds were in the Darcy and non-Darcy (transitional and Forchheimer) regimes. Heat fluxes were 14,998 and $$26{,}347\,\hbox {W/m}^{2}$$ for the Darcy and non-Darcy regimes, respectively. Measurements were focused on the thermally fully developed and an anticipated exit regions, with the latter region being often ignored in the literature. The experimental Nusselt number for the Darcy flow cases is compared to its analytical counterpart. A comparison shows good agreement, considering the approximations involved in the analytical solution and experimental errors. Previously unpublished phenomenon is presented in the behavior of Nusselt number for non-Darcy regimes. The experimental results and measuring technique can be used for validation of other analytical and numerical solutions, as well as in testing heat-exchange engineering designs based on metal foam.