Unsteady MHD Free Convective Flow of a Micro‐Polar Fluids Over a Vertical Porous Plate in the Presence of Radiation and Chemical Reaction

ABSTRACT Objective of the paper is to investigate the motion of an unsteady free convective MHD flow of a micro‐polar fluid over semi‐infinite vertically moving porous plate in the presence of chemical reaction and thermal radiation. A transverse magnetic field is applied, assuming a low magnetic Reynolds number. We have discussed the effects of heat radiation due to a heat source and first order chemical reaction within the medium. The perturbation method is applied to solve the nonlinear coupled partial differential equations in their dimensionless form, converting them into a system of ordinary differential equations, which are then solved analytically. The effects of magnetic field, medium permeability, buoyancy force, heat source, concentration gradient, Prandtl number, thermal diffusion, heat radiation, and first order chemical reaction on velocity, temperature and concentration are discussed graphically. The graphical representations are generated using MATLAB software. For engineering interest, their effects on skin friction, heat and mass transfer in terms of Nusselt number and Sherwood number are discussed; numerical values are shown in tabular form. The results show that magnetic fields reduce fluid velocity, while thermal radiation decreases temperature, and chemical reactions lower concentration. Radiation increases skin friction and heat transfer, while chemical reactions reduce mass transfer. Findings have relevance in various problems and situations arising with micro‐polar fluidic devices, industrial like petroleum and lubrication, mixing etc.