Abstract
In this study, the optimum magnetic field intensity to overcome the flow and heat transfer suppression offered by a saturated porous zone in the square cavity of side length L is examined. The porous zone is kept at the central vertical area in the square cavity with a thick zone of L/4, and the magnetic field is also maintained in the central vertical zone with an L/2 thick zone oriented in the direction transverse to gravity and temperature gradient. The flow solver including the Darcy-Forchheimer term in the Navier-Stokes equation merged with Maxwell’s electrodynamics equation and the energy equation is framed in OpenFOAM 10. The Darcy value for the porous zone is fixed at 10−3, and the magnetic field is varied as Hartmann number Ha = 0, 10, 15, 20. The buoyancy-induced flow is regulated by the Rayleigh number Ra = 105 and Prandtl number Pr = 0.02. The numerically obtained results clarify that the porous zone decreases the convection heat transfer and inhibits the flow. However, the magnetic field brings back the convection flow through the porous zone, where isotherms are again shifted like a convection flow pattern. Consequently, the magnetic field imposed orthogonal to gravity and temperature gradient improves the heat transfer by 30% compared to porous media flow.
