Heat and Mass Transfer on Magnetohydrodynamics Free Convection Over a Vertical Plate: Non‐Linear Buoyancy, Radiation and Chemical Reaction Effects

This study investigates the MHD laminar boundary layer flow of an electrically conducting fluid over a vertical plate, incorporating chemical reactions, nonlinear radiation, and convective boundary conditions. The novelty of this model lies in the strong coupling between the nonlinear radiation term and nonlinear density variation with temperature (NDT) and concentration (NDTC) under the influence of a magnetic field. The governing partial differential equations are transformed into a system of nonlinear ordinary differential equations via similarity variables and solved numerically using the MATLAB bvp4c method. The obtained results were compared with previously published work and found an excellent agreement. Results demonstrate that increasing magnetic intensity suppresses fluid velocity due to the Lorentz force while elevating temperature and concentration profiles. In contrast, nonlinear radiation, Grashof numbers, NDT, and NDTC act as accelerating forces that enhance fluid motion and thin the thermal and solutal boundary layers. Quantitatively, NDT increases the skin friction coefficient, Nusselt number, and Sherwood number by 22.38%, 11.95%, and 2.04%, respectively, while NDTC yields increases of 26.83%, 4.68%, and 1.24%, respectively. Furthermore, chemical reactions reduce concentration and velocity but enhance the thermal boundary layer, a trend opposite to that of the convective parameter. These findings are crucial for high‐temperature engineering applications, such as nuclear cooling, polymer extrusion, and chemical vapor deposition, where large gradients invalidate linear density assumptions and require realistic predictions of heat and mass transfer in the presence of magnetic effects.