Thermohydraulic characteristics of magnetic nanofluid in mini channels under the influence of an external magnetic field

Abstract

Engineers and designers are increasingly challenged to maximize processing speed inside a constricted form factor as electronic components increasingly become smaller. Smaller form factors need downsizing of the tools used to distribute that heat, and faster processors entail increasing power usage, which creates additional heat. These factors compel creative engineers and designers to develop systemic solutions in which every factor in the power equation of a device is optimized. Hence, in the present work, results of numerical simulations of mini-channel heat sinks are analyzed and compared. The influences of design, inclination angle, magnetic field, and nanofluid on the thermal and flow performance are evaluated numerically. The results obtained from the investigation shows increments in the Nusselt number with an increase in magnetic field intensity and Reynolds number. The vortices formed in the fluid domain provide intense fluid mixing. The average fluid temperature rises and the thickness of the boundary layer increases and the Nusselt number further decreases in the region of the magnetic field. The magnetic field's intensity determines how big the vortex will be; the stronger the magnetic field, the faster the vortex will swirl which results in the formation of secondary vortices, which, in turn, contribute to intense mixing of fluid. The vortices become larger and combine to create a single vortex when the magnetic field strength increases, and this pattern holds true for greater magnetic field strengths. The findings clearly demonstrate that the reduction in frictional pressure drop exceeds the rise in pressure drop due to vortex formation, even though there must be an increase in pressure drop owing to vortex formation. When the flow blockage is greatest, the pressure drop is also greatest. The thermal performance factor for all the configurations is evaluated. Except for 1200 G, for all other magnetic intensities and Reynolds number, the thermal performance is above unity.