Forchheimer forced convection in a rectangular channel partially filled with aluminum foam

Abstract

In this paper, heat transfer and pressure drop were investigated by placing open-cell aluminum foam in different ratios according to the channel volume in a hydrodynamically fully developed rectangular channel. Aluminum foams were placed inside the channel in the thermally developing flow region in four different ways; filling the channel completely, convex, concave or triangular against the flow. Air was used as working fluid. The experiments were performed over a wide range of the Reynolds number (968 < ReDh < 29,624) based on the channel equivalent diameter. The aluminum foam was used in the experiments having two different pore densities (10 and 20 pores per inch, PPI). Empirical equations were derived from the results obtained from the experiments in both laminar and turbulent channel flow regimes. The experiments for heat transfer and pressure drop applications in the porous medium led to original and useful findings; namely, while obtaining the highest value of heat transfer in the channel fully filled with aluminum foam according to the Reynolds number and pore density, the pressure drop and also the pump power increased substantially. This was defined as the thermal enhancement factor (TEF). The value of TEF for 20 PPI was greater than 10 PPI for both laminar and turbulent flow at a fully filled state. In contrast, the value of the TEF and heat transfer capability (HTC) was always higher for 10 PPI when the channel is partially filled with aluminum foam. © 2016 Elsevier Inc.