Abstract
A numerical study of combined effects of thermal stratification and convective heating for the two-dimensional unsteady flow of hydromagnetic natural convection of nanofluid with buoyancy effects against permeable stretching sheet in presence of electric field is presented. Viscous dissipation and Ohmic heating, as well as radiative heat transfer, are taken into account in the heat convection field. The impact of the chemical reaction due to zero flux of nanoparticle concentration is adopted. The model associated with Brownian motion and thermophoretic diffusion is controlled with slip flow as well as the convective boundary conditions with effects of thermal stratification are employed. Suitable similarity transformations are utilised to transform the governing equations into a couple of ordinary differential equations. The transformed equations systems are then solved numerically using Keller box method. The effects of the pertinent parameters on dimensionless nanofluid velocity, temperature and concentration as well as the skin friction, and Nusselt number are examined. The numerical data obtained in the present investigation are validated and are in good agreement with the previously published data. The numerical computations reveal that that electric and magnetic fields exhibit opposite's flow behaviour due to fluid motion and both enhance the fluid temperature field. The consequence of convective heating intensifies the nanofluid temperature for higher values as thermal stratification reduces the profiles and its associate's thermal boundary layer thickness.