Influence of Soret and Dufour on MHD buoyancy-driven heat and mass transfer over a stretching sheet in porous media with temperature-dependent viscosity

This work focuses on the effect of variable viscosity and thermal conductivity on mixed convection flow and heat transfer along a semi-infinite non-linear stretching sheet embedded in a saturated porous medium in the presence of viscous dissipation, Soret and Dufour, thermal radiation, non-uniform heat source/sink and first-order chemical reaction. The partial differential equations governing the problem under consideration have been transformed into a system of ordinary differential equations which are solved numerically by applying the shooting algorithm with Runge–Kutta–Fehlberg integration scheme over the entire range of physical parameters. The effects of various physical parameters on the dimensionless velocity, temperature and concentration profiles are depicted graphically and analyzed in detail. A comparison with previously published work has been carried out and the results are found to be in good agreement. Numerical results for local skin-friction coefficient, local Nusselt number, and local Sherwood number are tabulated for different physical parameters.

► Increase in the non-linear stretching index is to decrease the velocity profile.
► Temperature profiles increase with decrease in the Soret number (or increase in Dufour number).
► Local skin-friction coefficient decreases with increase in magnetic field and chemical reaction parameters.
► Concentration profile decreases with increase in the chemical reaction parameter.
► Increase in the thermal conductivity parameter is to increase the velocity and temperature profiles.