Heat transfer analysis on ferrofluid natural convection system with magnetic field

Free convection of Fe3O4-water inside the porous enclosure was investigated in the presence of magnetic fields. The SIMPLE algorithm was employed to solve the equations based on FVM. The inner wall of enclosure was considered in the constant flux and that of outer wall were at a constant temperature, respectively. Also, two other walls are thermal insulation and the radiation reflects to inner semi-annulus. An electric current coil for producing a magnetic field is wrapped around the semi-annulus. The effects of Ra-p = 10 and 1000, the concentration (phi(Ave) = 0; 0.01 and 0.03), porosities (epsilon = 0.4 and 0.7) and magnetic numbers (0 <= Mn <= 8 x 10(7)) are investigated considering first laws of thermodynamics. The findings revealed that the mean Nusselt number has direct relation with the magnetic number, porosity, Ra-p and concentration, respectively. Moreover, increasing volume fraction from 0.01 to 0.03 in high magnetic number enhanced the Nusselt number by 32 %. (c) 2023 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Ain Shams University. This is an open access article under the CC BY license (http.//creativecommons.org/licenses/by/4.0/).