Magnetic field effects on natural convection flow of nanofluid in a rectangular cavity using the Lattice Boltzmann model

Abstract

This work applied the Lattice Boltzmann Method (LBM) to investigate the effect of CuO nanoparticles on natural convection with magnetohydrodynamic (MHD) flow in a square cavity. The left and right vertical walls of the cavity were kept at constant temperatures, Th and Tc, respectively, with two insulated walls at the top and bottom. A uniform magnetic field was used in a horizontal direction. Results were carried out for different Hartmann numbers ranging from 0–100, Rayleigh numbers from 103–105 and the solid volume fraction from 0 to 0.05. Effects of the solid volume fraction and magnetic field on hydrodynamic and thermal characteristics were investigated and discussed. The averaged Nusselt numbers, on hot wall, streamlines, temperature contours, and the vertical component of velocity for different values of a solid volume fraction, Hartmann and Rayleigh numbers were illustrated. The results indicate that the averaged Nusselt number increases for nanofluids when increasing the solid volume fraction, while, in the presence of a high magnetic field, this effect decreases.