THERMAL INSTABILITY OF HYDRO-MAGNETIC JEFFREY NANOFLUIDS IN POROUS MEDIA WITH VARIABLE GRAVITY FOR: FREE-FREE, RIGID-RIGID AND RIGID-FREE BOUNDARIES

This article presents a numerical and graphical examination of thermal instability of hydro-magnetic Jeffrey nanofluids in porous media with variable gravity for: free-free, rigid-rigid and rigid-free boundaries by using Galerkin technique and normal mode analysis. The Darcy model is employed. Four different gravity variable parameters : exponential, parabolic and linear are taken and their effects on the Jeffrey parameter, magnetic field, moderated diffusivity ratio, porosity of porous media, Lewis number and nanoparticle Rayleigh number on stationary convection have been calculated numerically and graphically shown for all three boundary conditions namely free-free, rigid-rigid and rigid-free. The necessary conditions for frequencies of the oscillatory mode under all three boundaries have been calculated.