Numerical Investigation of Heat Transfer in a Four-sided Lid-driven Cavity with Porous Medium

This study numerically examines magnetohydrodynamic (MHD) mixed convection heat and mass transfer in a lid-driven square cavity partially filled with a porous medium. The square cavity configuration includes four independently moving lids, adiabatic horizontal walls, and differentially heated vertical walls, with simultaneous diffusion–convection driven species transport. The Navier-Stokes, energy, and species equations are numerically solved using commercial software COMSOL Multiphysics ۶.۲ based on the finite-element method. The governing physical parameters are systematically examined, including the Hartmann number (Ha = ۱۰ – ۴۰), Darcy number (۰ ≤ Da ≤ ۱), Eckert number (۰ ≤ Ec ≤ ۱), Richardson number (۰ ≤ Ri ≤ ۱۰۰), Schmidt number (۰ ≤ Sc ≤ ۰.۵), and Joule heating induced by the applied magnetic field. The flow regime is dominated by conduction and circulation suppresses when Ha increases. ۶۵ to ۷۰% suppression in convection is observed at Ha = ۴۰, while ۴۵% of enhancement in heat transfer is observed for Da = ۰.۱ to ۰.۷. Ec increases the core temperature by ۱۲% – ۱۸%, reducing  correspondingly. Viscous dissipation and Joule heating rise temperature levels through internal energy generation. Increasing Da enhances convective transport, while larger Sc produces sharper concentration gradients and thinner solute boundary layers. A transition from forced to buoyancy-dominated flow is also observed with increasing Ri. These findings offer improved physical insight into coupled heat–mass transfer in MHD porous systems, relevant to thermal management, electrochemical devices, and energy conversion technologies.

کلیدواژه ها:

Darcy number ، Eckert number ، Hartmann number ، Magnetohydrodynamic ، Porous square cavity