Effects of Chemical Reaction, Thermophoresis, and Brownian Motion on Natural Convection MHD Casson Fluid Flow over Vertical Plates with Linear and Nonlinear Thermal and Solutal Expansion

This study investigates the natural convection MHD Casson fluid flow over vertical plates, incorporating the effects of chemical reactions, thermophoresis, Brownian motion, nonlinear thermal radiation, and heat source. Using the Boussinesq approximation, we analyze density variations with respect to temperature and concentration. The convective surface boundary condition is applied to the plate, and the governing partial differential equations are transformed into ordinary differential equations, solved numerically using the Runge–Kutta method coupled with the shooting technique. Graphical analysis highlights the impact of key flow parameters, such as thermal radiation, heat source/sink, Brownian motion, thermophoresis, and magnetization, on velocity, temperature, and concentration profiles. Additionally, numerical calculations of the local Nusselt number, Sherwood number, and skin friction coefficient are performed to provide deeper insights into the behavior of these parameters. The evaluation of skin friction, Nusselt number, and Sherwood number through tabular analysis quantifies the effects of these factors on fluid flow. Furthermore, an increase in reversible fluid flow is observed for higher nonlinear density variations with temperature and concentration.