Abstract
In this paper, a numerical study for magnetohydrodynamic free convection in a square enclosure with cold irregular obstacles at the center of the cavity is performed. The cavity is filled with nanofluids (Al2O3-water) embedded in an isotropic porous medium. All walls of the enclosure have heated parts near the corners (heated corners) while the remaining parts of the top and bottom walls are thermally insulated and the remaining parts in the left and right walls are cold. The governing equations are converted to dimensionless form and then solved numerically using the finite difference method. The problem is controlled by various parameters such as the Rayleigh number, the heat source length, the Hartmann number, the volume fraction of the suspended nanoparticles, and the heat generation. The results are presented in forms of the isotherms, streamlines, and local and average Nusselt numbers. The obtained outcomes show good agreement compared with the past published studies.