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Veena Sharma ¹, Anukampa Thakur ¹, Priti Bala ¹

Affiliations
1 Department of Mathematics & Statistics, H.P. University, Shimla-171 005, IN

Abstract

A study has been made of the instability of an electrically conducting stratified viscoelastic Rivlin-Ericksen fluid/plasma arranged in a horizontal strata to include a variable horizontal magnetic field. Applying the linear stability theory and normal mode technique to a set of partial differential equations, the solutions of an eigen value problem have been obtained by assuming exponential vertical stratifications in density, neutral gas density, viscosity, viscoelasticity and magnetic field. Using these solutions, the dispersion relation so obtained has been analysed numerically. It has been found that viscosity, viscoelasticity , collisional frequency and magnetic field have stabilizing effects on the growth rates for unstable configuration under certain wave-number band.

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Veena Sharma ¹, Anukampa Thakur ¹, Abhishek Sharma ¹

Affiliations
1 Department of Mathematics and Statistics, Himachal Pradesh University, Shimla-5, IN

Abstract

In this study, the effect of Hall currents on the onset of stability of saturating porous media an electrically conducting ferromagnetic fluid heated from below using linear stability analysis is investigated. Using the Darcy law to modify the ferromagnetic fluid 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 prepones the onset of convection under certain conditions implying thereby the destabilizing effect.

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