Investigation of FHD effects on heat transfer in a differentially heated cavity partially filled with porous medium utilizing Buongiorno’s model

The present work reports the effects of ferro-hydrodynamics on heat transfer and fluid flow in a cavity partially filled with a porous medium for the first time. Different magnetic, flow and porosity parameters, including magnetic number, magnet position, Rayleigh number, Darcy number and the porous medium filling ratio, are studied numerically. To calculate the nanoparticle distribution inside the cavity, Buongiorno’s two-phase non-homogenous model has been utilized. The results of validation tests with the previous works show very good agreement between the results. Based on the outcomes, the best heat transfer enhancement will occur at a specific position of the magnet near the wall. At this position, the average Nusselt number enhancement amounts to 12%. On the other hand, the intensity of the magnetic field can cause more than 55% increase in the average Nusselt number. This enhancement is shown to fade in large Rayleigh numbers. Magnet size is another important magnetic property that causes up to 48% intensification in Nu. Furthermore, the ratio of the fluid to porous region is shown to have a significant effect on heat transfer rates which can grow up to 150%. Rayleigh number is shown to have a strong influence on the Nusselt number. Impermeability of the porous medium alters the heat transfer rates up to 80%.