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.

中文翻译：

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椭圆形方孔中热角对磁-纳米流体自然对流的影响

在本文中，对在空腔中心处有冷不规则障碍物的方形外壳中的磁流体动力自由对流进行了数值研究。空腔中充满了纳米流体（Al ₂ O ₃-水）包埋在各向同性的多孔介质中。机箱的所有壁在拐角附近（受热的拐角）都有受热部分，而顶壁和底壁的其余部分是热绝缘的，而左，右壁的其余部分是冷的。控制方程被转换为无量纲形式，然后使用有限差分法进行数值求解。该问题由各种参数控制，例如瑞利数，热源长度，哈特曼数，悬浮的纳米颗粒的体积分数以及热量的产生。结果以等温线，流线以及局部和平均Nusselt数的形式表示。与过去发表的研究相比，获得的结果显示出良好的一致性。