Electro-thermal convection in a Brinkman porous medium saturated by nanofluid

Thermal instability in a horizontal layer of nanofluid with vertical AC electric field in a porous medium is investigated. Brinkman-Darcy model is used for the momentum equation. The model used for nanofluid incorporates the effect of Brownian diffusion, thermophoresis and electrophoresis. The flux of volume fraction of nanoparticles is taken to be zero on the isothermal boundaries and the eigenvalue problem is solved by using the Galerkin method. Linear stability theory based upon the normal mode technique is employed for stability analysis. Oscillatory convection has been ruled out for the problem and graphs have been plotted to study the effects of Brinkman-Darcy number, Lewis number, modified diffusivity ratio, concentration Rayleigh number, AC electric Rayleigh number and porosity parameters on stationary convection.