Numerical Investigation of Magnetohydrodynamic Heat Transfer and Thermal Regulation of Al 2 O 3 –Cu Hybrid Nanofluid Flow in a Corrugated Microchannel with Circular Obstacles
Abstract
This study presents a numerical investigation of steady laminar magnetohydrodynamic (MHD) flow of Al 2 O 3 -Cu/water hybrid nanofluid. The flow is confined in two-dimensional corrugated microchannel containing circular obstacles, targeting thermal regulation as well as biomedical engineering applications. The coupled equations are solved using a finite-element (FE) framework in COMSOL Multiphysics. The Lorentz force induced by a uniform transverse magnetic field is incorporated in the momentum balance. The thermophysical properties of the hybrid nanofluid are modeled through user-defined correlations. The presence of hybrid nanoparticles significantly enhances the average Nusselt number particularly in obstacle-assisted mixing zones generated by wall corrugation and bluff bodies. Magnetic field introduces Lorentz damping that suppresses excessive flow separation as well as stabilizes thermal gradients. The combined effects of geometric modulation, magnetic control, and hybrid nanoparticle dispersion provide an effective mechanism for tunable heat transfer moderation. The findings offer design guidance for magnetically controlled microchannel heat sinks, bio-microfluidic cooling devices, targeted drug-delivery channels, hyperthermia-assisted therapeutic systems, and lab-on-chip platforms employing hybrid nanofluids.