Variable Gravity Effect on the Thermal Instability of Ferrofluid in a Brinkman Porous Medium
[1]
Ankuj Bala, Department of Mathematics, Dravidian University Srinivasavanam Kuppam, Chittoor, Andhra Pradesh, India.
[2]
Ramesh Chand, Department of Mathematics, Government Arya Degree College Nurpur, Himachal Pradesh, India.
Effect of variable gravity on the thermal instability in a horizontal layer of ferrofluid in a Brinkman porous medium is investigated by using Galerkin weighted residuals method. Linear stability theory based upon perturbation method and normal mode technique is used to find expressions for Rayleigh number and critical Rayleigh number. ‘Principle of Exchange of Stabilities’ hold and the oscillatory modes are not allowed. It is found that decreasing gravity parameter has stabilizing effect while increasing gravity parameter has destabilizing effect on the stationary convection. It is also found that magnetization parameters M3 and buoyancy magnetization M1 have destabilizing effect while Brinkman Darcy number D̃a has stabilizing effect on the fluid layer.
Ferrofluid, Brinkman Darcy Number, Variable Gravity, Perturbation Method, Galerkin Method
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