Applied Sciences (Jan 2021)
Fe<sub>3</sub>O<sub>4</sub>-Water Nanofluid Free Convection within an Inclined 2D Rectangular Enclosure Heated by Solar Energy Using Finned Absorber Plate
Abstract
This work investigates a hydrodynamic problem involving the Fe3O4-Water nanofluid. The novelty of this investigation lies in the fact that the nanofluid free convection is evaluated within a specific rectangular enclosure having a finned absorber plate as the top wall, heated by solar energy. The fins below the absorber plate permit to enhance heat transfer towards the nanofluid. A numerical simulation is carried out in order to predict the influence of Rayleigh number, nanofluid layer position, enclosure inclination angle, and absorber plate fins height on the nanofluid flow (in terms of streamlines and velocity magnitude) and heat transfer (in terms of temperature and Nusselt number divided by a certain thermal conductivity ratio). Numerical results show a nanofluid buoyancy enhancement and a temperature distribution homogenization, when the Rayleigh number increases, all the more important and pushed to the right area of the enclosure, as the inclination angle of the enclosure is higher. For relatively low fin heights, the nanofluid buoyancy enhancement is all the more important and pushed to the right area of the enclosure as the inclination angle is high. As the fin height increases, the temperature distribution becomes more homogenous.
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