Free convection and thermal radiation of nanofluid inside nonagon inclined cavity containing a porous medium influenced by magnetic field with variable direction in the presence of uniform heat generation/absorption

Abstract

Purpose

The purpose of this paper is to study the natural convection and radiation heat transfer inside Nonagon inclined cavity with variable heated source length, which contains a porous medium saturated with nanofluid in the presence of uniform heat generation or absorption under the effect of uniform magnetic field with variable direction. The shape factor of nano particles is taking account for the model of nanofluid.

Design/methodology/approach

This study is established in two-dimensional space. The 2D numerical study is effectuated with Comsol Multiphysics based on the on the finite element method. The 2D equation system is exposed on dimensionless form taking into account the boundary conditions.

Findings

Results obtained show that the convection heat transfer is ameliorated with the augmentation of heated source length. The convection heat transfer is enhanced by increasing Rayleigh, Darcy numbers and the heated source length; however, it is reduced by rising Hartmann number. The presence of radiation parameter lead to improve the convection heat transfer in the presence of both uniform heat generation/absorption. The average Nusselt number reaches a maximum for an inclination of cavity γ = 45° and a minimum for γ = 60°. Both the increase of the shape factor of nano particles and the solid fraction of nano particles improve the convection heat transfer.

Originality/value

Different studies have been realized to study the heat transfer inside cavity contains porous medium saturated with nanofluid under magnetic field effect. In this work, the Nonagon geometric of cavity studied has never been studied. In addition, the effect of radiation parameter with relation of the shape factor of nanoparticles in the presence of uniform heat generation/absorption on the heat transfer performance have never been investigated. Also, the effect of magnetic field direction with relation of the inclination cavity on heat transfer performance.

Citation

Massoudi, M.D., Ben Hamida, M.B. and Almeshaal, M.A. (2021), "Free convection and thermal radiation of nanofluid inside nonagon inclined cavity containing a porous medium influenced by magnetic field with variable direction in the presence of uniform heat generation/absorption", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 31 No. 3, pp. 933-958. https://doi.org/10.1108/HFF-04-2020-0223