THERMOSOLUTAL CONVECTION IN A HETEROGENEOUS FLUID LAYER IN POROUS-MEDIUM IN THE PRESENCE OF A MAGNETIC-FIELD

The thermosolutal instability in porous medium in a viscous, conducting, incompressible and heterogeneous fluid layer confined between two free boundaries is studied under linear theory, when the whole system is immersed in a uniform vertical magnetic field. The existence of stationary, oscillatory and non-oscillatory modes are discussed. A variational formulation of the problem is also established and numerical computations are done to study the influence of various parameters. It is found that heterogeneity has a destabilizing effect and the Chandrasekhar number and porosity parameter have stabilizing effects on the system.