Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Influence of a magnetic field induced by a conducting wire on the flow patterns and heat transfer of thermosensitive ferrofluid inside a square cavity
Submission Author:
Adriano Rosa , DF
Co-Authors:
Luís Castro, Adriano Rosa, Taygoara Oliveira
Presenter: Adriano Rosa
doi://10.26678/ABCM.COBEM2023.COB2023-1619
Abstract
In this work, we investigate how an external magnetic field induced by the electric current passing through a conducting wire affects the flow and heat transfer of a thermosensitive ferrofluid in a bottom-heated two-dimensional cavity. We assume an incompressible and laminar flow of a Newtonian ferrofluid whose magnetic susceptibility and density are dependent on the temperature. Under the simultaneous action of the gravitational and external magnetic field, a complex flow develops inside the cavity. We change the intensity of the external magnetic field aiming to understand how the flow field, temperature distribution, and net heat transfer are affected. We use a numerical methodology to solve mass, linear momentum, and energy equations. The pressure-velocity coupling is carried out by a projection method that combines second-order finite differences for spatial discretization, with a Crank-Nicolson scheme for time evolution. The method is verified using results from the literature. Our findings reveal that the magnetic field has a significant influence on the topology of the flow and temperature fields, consequently impacting the overall heat transfer. It is possible to use the magnetic field generated by a conducting wire to change the net heat transfer through the cavity. We found that the Nusselt is a growing function of the magnetic field intensity, except for a specific Rayleigh number. Furthermore, we identify non-stationary regimes at intermediate magnetic Rayleigh numbers, which we attribute to a transition in the flow topology induced by the magnetic field.
Keywords
thermomagnetic convection, ferrofluid, Heat transfer, Nusselt number, Numerical simulation
