Investigation of Natural Convection Boundary Layer Heat and Mass Transfer of MHD water-Al2 O3 Nanofluid in a Porous Medium

In this study, a similarity solution is employed to investigate heat and mass transfer of water-Al2 O3 nanofluid near a vertical flat surface embedded in a non-Darcy porous medium and in the presence of a constant magnetic field. The wall is at constant temperature Tw and concentration Cw which are greater than the ambient temperature T∞ and concentration C∞, respectively. The effect of different parameters such as the Grashof number, Hartmann number, Soret number, Dufour number, Lewis number, Buoyancy number, mass flux and volume fraction of nanoparticles on flow field and heat and mass transfer are examined. The obtained results indicate that the temperature and concentration boundary layers become thicker when the mass flux parameter increases. Also, when the volume fraction and Buoyancy and Soret numbers increase, the heat transfer coefficient increases too. The Sherwood number decreases when the volume fraction of nanoparticles, Hartmann and Soret numbers augment.