Thermal and Fluid-Flow Characteristics of Silver-Water Nanofluid in a Metal-Foam Filled Channel

Abstract

In this study, mixed convection heat transfer of silver-water nanofluid was experimentally investigated under laminar flow regime inside a horizontal rectangular channel filled with an open-cell copper foam. Thermophysical properties of silver-water nanofluid at 1,000, 2,000, and 4,000 ppm concentrations were also measured. The morphological properties of copper foam were further measured by image processing. At the highest Reynolds number, metal-foam in the channel could increase the heat transfer coefficients of the top and bottom walls 1.6–3.7 times, respectively. Compared to deionized water, 15%, 20%, and 26% enhancement in heat transfer coefficients were achieved at nanofluid concentrations of 1,000, 2,000, and 4,000 ppm, respectively. The heat transfer coefficients of the top and bottom plates were increased by 4.7 and 2.7 time, respectively, at the highest Reynolds number and nanofluid concentration. Finally, two performance coefficients were proposed for the overall evaluation of the simultaneous application of porous-medium and nanofluid.