Combined Effect of Rotation and Hall Currents on Magneto-Thermal Convection of Ferromagnetic Fluids Saturating Porous Medium

S. Gupta¹

Section:Research Paper, Product Type: Journal-Paper
Vol.5 , Issue.12 , pp.15-22, Dec-2019

Online published on Dec 31, 2019

Copyright © S. Gupta . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
 

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Abstract :
In this study, the effect of Hall currents and rotation on the onset of convection in a porous medium layer saturated by an electrically conducting ferromagnetic fluid heated from below using linear stability analysis is investigated. Darcy law for the ferromagnetic fluid is used to model the momentum equations for a porous medium. The employed model incorporates the effects of polarization force and body couple. The coupled partial differential equations governing the physical problem are reduced to a set of ordinary differential equations using normal mode technique. These equations are solved analytically for stress- free boundaries and numerical results are computed by obtaining approximate solutions using Galerkin method using the software Mathematica for the case of stationary convection. It is found that the magnetic field and magnetization have a stabilizing effect as such their effect is to postpone the onset of thermal instability; whereas Hall currents are found to hasten the same. The medium permeability and rotation hastens the onset of convection under certain conditions.

Key-Words / Index Term :
Hall currents, rotation parameter, ferromagnetic fluid, medium permeability, medium porosity

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