Magnetohydrodynamic natural convection heat transfer of a nanofluid confined in a square open cavity subjected to a linear varying temperature

A FORTRAN in-house code is elaborated to investigate the two-dimensional and laminar natural convection flow for a Newtonian fluid in an open square enclosure saturated with a nanofluid and subjected to an external magnetic field. Except for the bottom wall, which is heated with linear varying temperature, all cavity walls are held at a constant cold temperature. Applying magnetic fields in certain directions can serve to regulate and control fluid flow patterns and heat transmission for cooling electronic components. By embracing the stream function vorticity formulation, the physical phenomenon is modeled mathematically by a set of transport equations. The dimensionless governing equations are discretized utilizing the finite volume method and solved numerically using a relaxation iterative method. The examination of specific parameters encompassing the Hartmann number, nanoparticle volume fraction, magnetic field inclination angle, and Rayleigh number over a wide range was accomplished to understand their effects on heat transfer and flow patterns. The outcomes denote that, in convection heat transfer, regardless of the magnetic field’s inclination angle, increasing its intensity diminishes the volume of fluid drawn into the cavity and also causes poorer heat transfer and diminished fluid motion. Conversely, the incorporation of nanoparticles enhances heat transfer and influences fluid motion in distinct ways: It promotes fluid movement in the absence of a magnetic field, whereas in the presence of a magnetic field, it hinders fluid motion.