Two-phase modeling of the free convection of nanofluid inside the inclined porous semi-annulus enclosure

In the present paper, the modeling of the free convection of two-phase nanofluid inside the inclined porous semi-annulus enclosure is considered. The cavity is filled with Fe3O4-water magnetic nanofluid. Buongiorno and Darcy models are used for modeling two-phase and porous media, respectively. The governing equations are discretized by finite volume method and SIMPLE algorithm. The effect of parameters such as inclination angle of cavity (0 <= theta <= 90), porous Rayleigh number (10 <= Ra-p <= 10(3)), porosity number (epsilon = 0 .4 and 0.7), and volume fraction of nanoparticles (0 <= phi(Ave) <= 0.04) on the flow pattern, temperature field, nanoparticle distribution, and Nusselt number are studied. In low porous Rayleigh numbers, Nusselt number is not the function of porosity number and the inclination angle of the enclosure. Also, Nusselt number increases by adding the volume fraction of nanoparticles. However, in high porous Rayleigh numbers, the heat transfer rate is reduced by increasing the inclination angle of the enclosure. Furthermore, with the increase in the porosity number, Nusselt number is increased.