Thermomagnetic convection in porous media: Effect of anisotropy and local thermal nonequilibrium

Abstract

The onset of thermomagnetic convection in an anisotropic layer of Darcy porous medium in the presence of a uniform vertical magnetic field is investigated using a local thermal nonequilibrium (LTNE) model for energy equation representing the solid and fluid phases separately. Anisotropies in permeability as well as in fluid and solid thermal conductivities are considered. The principle of exchange of stability is shown to be valid. Asymptotic solutions for the Rayleigh number for both small and large values of scaled interphase heat transfer coefficient t H are presented and the comparison of results with those computed numerically shows good agreement. The mechanical and thermal anisotropy parameters have opposing influence on the stability characteristics of the system. Besides, the influence of magnetic parameters on the instability of the system is also reported. © 2017 Trans Tech Publications, Switzerland