Transient MHD Fluid Flow Past a Moving Vertical Surface in a Velocity Slip Flow Regime

Abstract

The problem of unsteady MHD fluid flow past a moving vertical surface in a slip flow regime is presented. The model is built on the assumption that the flow is naturally convective with oscillating time-dependent and exponentially decaying suction and permeability, double-diffusion, viscous dissipation, and temperature gradient-dependent heat source, and non-zero tangential velocity at the wall; the fluid is viscous, incompressible, Newtonian, chemically reactive, and magnetically susceptible; the surface is porous, and electrically conductive, and thermally radiative. The governing partial differential equations are highly coupled and non-linear. For easy tractability, the equations are reduced to one-dimensional using the one-dimensional unsteady flow theory. The resulting equations are non-dimensionalized and solved using the time-dependent perturbation series solutions, and the Modified Homotopy Perturbation Method (MHPM). The solutions of the concentration, temperature, velocity, rates of mass and heat diffusion, and wall shear stress are obtained, computed, and presented graphically and quantitatively, and analyzed. The results among others, show that the increase in the: Schmidt number increases the fluid concentration, velocity, the rate of heat transfer to the fluid, and the stress on the wall, but decreases the rate of mass transfer to the fluid; Magnetic field parameter decreases the fluid velocity and stress on the wall; Slip parameter increases the flow velocity, but decreases the stress on the wall; Permeability parameter increases the flow velocity and the stress on the wall. These results are benchmarked with the reports in existing literature and they agree.