Document Type: Research Paper

Authors

Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran

Abstract

Natural convection heat transfer is studied numerically in a triangular enclosure. The enclosure is isosceles right triangle and its bottom wall is hot, the hypotenuse is cold and the other wall is adiabatic. Also, a vertical magnetic field is applied in the enclosure, and there is hybrid nanofluid inside the enclosure. This study is conducted for Rayleigh numbers of 103-105, the Hartmann numbers between 0-80, and the volume fraction of nanofluid is between 0-2 percent. Based on the obtained results, as the Hartmann number augments, the temperature of the center of the enclosure decreases due to weakening of the heat transfer flow by increasing the magnetic field forces. In addition, as the Hartmann number augments, the streamlines approach to the walls because the horizontal momentum forces decrease when the Hartmann number increases. Furthermore, by increasing the density of nanoparticles, the heat transfer rate increase, and as a result, heat transfer builds up. Finally, heat transfer improve when the hybrid-nanofluid is employed rather than ordinary nanofluid.

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