Thermal Instability in a Horizontal Layer of Ferrofluid in Anisotropic Porous Medium
Ankuj Bala, Department of Mathematics, Dravidian University Srinivasavanam Kuppam, Chittoor, Andhra Pradesh, India.
Ramesh Chand, Department of Mathematics, Government Arya Degree College Nurpur, Himachal Pradesh, India.
Thermal instability in a horizontal layer of ferrofluid saturated by anisotropic porous medium is investigated for free-free boundary conditions. A linear stability analysis based upon perturbation method and normal mode technique is used to study the onset of instabilities of ferrofluid saturated by anisotropic porous medium. Rayleigh number on the onset of stationary convection has been derived by using Galerkin method. Effect of anisotropy parameters and other parameters on stationary convection derived analytically. It is found that the thermal anisotropy parameter has stabilizing effect while mechanical anisotropy parameter and magnetization parameters have destabilizing effect on the stationary convection.
Ferrofluid, Magnetic Thermal Rayleigh Number, Anisotropic Porous Medium, Perturbation Method
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