On a Couple Stress Rivlin-Ericksen Ferromagnetic Fluid Heating From Below with Varying Gravity and Suspended Particles Through a Porous Medium

Abstract

The effect of suspended particles, couple stress and permeability of the medium on the thermal instability of a couple stress Rivlin-Ericksen ferromagnetic fluid with varying gravity fields through a porous medium are investigated. The dispersion relation has been developed and solved analytically using the normal mode approach and linear stability theory. For stationary conventions, it is found that suspended particles always have a destabilizing effect if  λ > 0 and a stabilizing effect if  λ < 0. Couple stress has a stabilizing effect if λ > 0 and a destabilizing effect if λ < 0. Permeability has a stabilizing effect if λ < 0 and a destabilizing effect if λ > 0. Magnetization always has a stabilizing effect either λ > 0 or λ < 0. Oscillatory modes are not allowed and the principle of exchange of stability is satisfied.