Optimizing thermal management with micropolar hybrid nanofluids in spatially dependent magnetic fields

Vortices play a pivotal role in fluid dynamics by enhancing fluid mixing and mass transport, making them crucial for numerous applications. Hybrid nanofluids, combining two types of nanoparticles, offer superior thermal conductivity and heat transfer compared to conventional nanofluids. This study examines the influence of localized magnetic fields on vortex dynamics in a micropolar hybrid nanofluid flow within a vertically oriented cavity, driven by moving horizontal lids along the +ve axis. Magnetic field strips are applied horizontally and vertically to control flow behavior. Using MATLAB-based algorithms and the finite difference method, we solve the governing equations of flow and heat transfer. Key parameters, including magnetic field strength, nanoparticle volume fraction, and Reynolds number, are analyzed for their effects on flow structures and temperature profiles. Results indicate that the magnetic field reduces microrotation and enhances laminar flow, influencing stress distribution and temperature gradients. These insights are valuable for optimizing microfluidic devices, heat exchangers, and drug delivery systems, where control over flow dynamics and temperature is essential.