Ferromagnetic Convection in a Rotating Ferrofluid Saturated Porous Layer

I. S. Shivakumara, Jinho Lee, C. E. Nanjundappa, M. Ravisha

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The effect of Coriolis force on the onset of ferromagnetic convection in a rotating horizontal ferrofluid saturated porous layer in the presence of a uniform vertical magnetic field is studied. The boundaries are considered to be either stress free or rigid. The modified Brinkman-Forchheimer-extended Darcy equation with fluid viscosity different from effective viscosity is used to characterize the fluid motion. The condition for the occurrence of direct and Hopf bifurcations is obtained analytically in the case of free boundaries, while for rigid boundaries the eigenvalue problem has been solved numerically using the Galerkin method. Contrary to their stabilizing effect in the absence of rotation, increasing the ratio of viscosities, Λ, and decreasing the Darcy number Da show a partial destabilizing effect on the onset of stationary ferromagnetic convection in the presence of rotation, and some important observations are made on the stability characteristics of the system. Moreover, the similarities and differences between free-free and rigid-rigid boundaries in the presence of buoyancy and magnetic forces together or in isolation are emphasized in triggering the onset of ferromagnetic convection in a rotating ferrofluid saturated porous layer. For smaller Taylor number domain, the stress-free boundaries are found to be always more unstable than in the case of rigid boundaries. However, this trend is reversed at higher Taylor number domain because the stability of the stress-free case is increased more quickly than the rigid case.

Original languageEnglish
Pages (from-to)251-273
Number of pages23
JournalTransport in Porous Media
Volume87
Issue number1
DOIs
Publication statusPublished - 2011 Mar 1

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Magnetic fluids
Viscosity
Coriolis force
Fluids
Hopf bifurcation
Galerkin methods
Buoyancy
Magnetic fields
Convection

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemical Engineering(all)

Cite this

Shivakumara, I. S. ; Lee, Jinho ; Nanjundappa, C. E. ; Ravisha, M. / Ferromagnetic Convection in a Rotating Ferrofluid Saturated Porous Layer. In: Transport in Porous Media. 2011 ; Vol. 87, No. 1. pp. 251-273.
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Ferromagnetic Convection in a Rotating Ferrofluid Saturated Porous Layer. / Shivakumara, I. S.; Lee, Jinho; Nanjundappa, C. E.; Ravisha, M.

In: Transport in Porous Media, Vol. 87, No. 1, 01.03.2011, p. 251-273.

Research output: Contribution to journalArticle

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