Effect of Non-Identical Magnetic Fields on Thermomagnetic Convective Flow of a Nanoliquid Using Buongiorno’s Model

Abstract

Energy transport intensification is a major challenge in various technical applications including heat exchangers, solar collectors, electronics, and others. Simultaneously, the control of energy transport and liquid motion allows one to predict the development of the thermal process. The present work deals with the computational investigation of nanoliquid thermogravitational energy transport in a square region with hot cylinders along walls under non-uniform magnetic influences. Two current-carrying wires as non-identical magnetic sources are set in the centers of two heated half-cylinders mounted on the bottom and left borders, while the upper wall is kept at a constant low temperature. Buongiorno’s model was employed with the impact of Brownian diffusion and thermophoresis. Governing equations considering magnetohydrodynamic and ferrohydrodynamic theories were solved by the finite element technique. The effects of the magnetic sources strengths ratio, Lewis number, Hartmann number, magnetic number, buoyancy ratio, Brownian motion characteristic, and thermophoresis feature on circulation structures and heat transport performance were examined. For growth of magnetism number between 0 and 103 one can find an increment of heat transfer rate for the half-cylinder mounted on the bottom wall and a reduction of heat transfer rate for the half-cylinder mounted on the left wall, while for an increase in magnetism number between 103 and 104, the opposite effects occur. Moreover, a rise in the Lewis number characterizes the energy transport degradation. Additionally, an intensification of energy transport could be achieved by a reduction of the thermophoresis parameter, while the Brownian diffusion factor and buoyancy ratio have a negligible influence on energy transport. Furthermore, the heat transfer rate through the half-cylinder mounted on the bottom wall declines with an increase in the magnetic sources strengths ratio.