Abstract |
We investigate theoretically the unsteady magnetohydrodynamic natural convection heat and mass transfer of a viscous, incompressible, electrically-conducting and radiating fluid over a porous vertical infinite plate. A uniform magnetic field of magnitude B0 is applied normal to the plate. An algebraic flux model is employed valid in the optically thin limit to simulate radiative heat transfer. Magnetic induction effects are excluded. However viscous heating and wall transpiration effects are included in the model. Following non-dimensionalization of the transient boundary layer conservation equations, a perturbative series expansion solution is derived. Expressions are also obtained for the surface shear stress (skin friction), Nusselt number and Sherwood number. An increase in magnetic body force parameter (m) is found to escalate temperatures in the regime whereas an increase in the conduction-radiation parameter (r) is shown to exert the opposite effect. Velocity is reduced considerably with a rise in conduction-radiation parameter (r) whereas the temperature is found to be markedly boosted with an increase in the viscous dissipation effect, i.e., Eckert number. Velocity and concentration functions are both reduced with an increase in Schmidt number. Similarly velocity and temperature are both considerably decreased with an increase in the free convection parameter, i.e., Grashof number. |
Keywords and phrases
magnetohydrodynamics, thermal radiation, mixed convection, wall suction, heat transfer, mass transfer, viscous dissipation, magnetic materials processing, perturbation solutions, unsteady.
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