On Thermosolutal-Convective Instability in Walters B’ Heterogeneous Viscoelastic Fluid Layer through Porous Medium

Abstract The thermosolutal convection in Walters B ’ heterogeneous viscoelastic fluid through Brinkman porous medium is considered. Following the linearized stability theory, Boussinesq approximation and normal mode analysis, the dispersion relation is obtained. Discussion of different modes revealed that the principle of exchange of stabilities is not valid for the problem. Further, it is found that oscillatory modes exist under certain conditions and non-oscillatory modes are unstable