A novel multi-banding application of magnetic field to convective transport system filled with porous medium and hybrid nanofluid

Abstract

Abstract To enhance the controllability of transport phenomena where magnetic fields are coupled with other multiphysics, a concept of multi-banding distribution of the magnetic field is presented in this work. For this study, a typical differentially heated convective system (of square shape) is considered with porous media saturated Cu–Al 2 O 3 /water hybrid nanofluid. The isothermal heating and cooling applied on the sidewalls of the system induce a buoyant flow, which is resisted by porous media and is dampened intermittently by the banded form of application of magnetic fields. The multi-banding distribution of magnetic fields is illustrated using four-band, two-band, and one-band configurations (all having the same effective length of the magnetic field). The results are generated by an in-house code adopting the finite volume method and the Brinkman-Forchheimer-Darcy model. For a set of selective parameters of the Hartmann number, Darcy number, hybrid nanofluid concentration, and Darcy-Rayleigh number, the study reveals that the multi-banding of the magnetic field through different numbers of bands has significant effects on transport phenomena and heat transfer. Heat transfer with the two-banded magnetic field is found more. Overall, the multi-banding technique is energy efficient compared to the whole domain magnetic field. This technique could be a prospective tool to control convective transports effectively and could open an area of potential researches in the area of multi-physical applications.