Unsteady MHD Casson Fluid Flow Past a Rotating Porous Plate with Thermal Radiation, Soret and Dufour Effects

A numerical investigation is carried out to analyze unsteady magnetohydrodynamic Casson fluid flow past a rotating vertical porous plate under the combined influences of thermal radiation, chemical reaction, and Soret Dufour cross-diffusion effects. The Casson fluid model is employed to account for yield stress characteristics associated with non-Newtonian rheology. The governing coupled nonlinear partial differential equations describing momentum, energy, and species concentration transport are nondimensionalized and solved numerically using a fourth order Runge Kutta method combined with a shooting technique. The effects of key dimensionless parameters on velocity, temperature, and concentration distributions are examined in detail. The results reveal that increasing magnetic field strength significantly suppresses both primary and secondary velocity components due to enhanced Lorentz force resistance. Thermal radiation and Dufour effects elevate the temperature field and increase thermal boundary layer thickness, whereas the Soret parameter plays a dominant role in modifying concentration profiles by enhancing thermo-diffusion. Furthermore, stronger chemical reactions and higher Schmidt numbers reduce mass transfer rates within the boundary layer. The present study elucidates the coupled thermo-solutal transport mechanisms in rotating porous media and provides useful insights for applications in thermal engineering, chemical processing, and biomedical flow systems.