Finite element analysis of mhd mixed convective heat and mass transfer stagnation-point flow in a circular annulus in highly porous medium with radiation

We investigate the combined effect of thermal radiation and radiation absorption on free and compelled convection flow through a porous medium in a very co-axial cylindrical duct where the boundaries are maintained at constant temperature and concentration. The Brinkman-Forchhimer extended Darcy equations which takes into consideration the boundary and inertia effects are utilized in the governing linear momentum equations. The effect of density variation is confined to the buoyancy term under Boussinesq approximation. The momentum, energy and diffusion equations are coupled equations. so as to get a stronger insight into this complex problem, we are using Galerkin finite element method with quadratic approximation technique. The behavior of velocity, temperature and concentration is analyzed for various parametric values at different axial positions. The rates of warmth and mass transfer have also been obtained for variations within the governing parameters. The local Nusselt number and native Sherwood number are illustrated to point out interesting features of the result.