Radiation-influenced magnetohydrodynamic flow of second-grade fluids with thermo-diffusion and slip interactions

This study investigates the slip flow characteristics of a radiative and chemically reacting magnetohydrodynamic (MHD) second-grade fluid over an infinite vertically moving plate. The primary objective is to analyze the combined effects of suction, Hall current, thermal radiation and thermo-diffusion (Soret effect) on the velocity, temperature and concentration fields under arbitrary plate motion. An unsteady mathematical model is developed for MHD second-grade fluid flow past a vertical plate with prescribed velocity (U0f(t)). The governing nonlinear partial differential equations incorporate mechanical and thermal slip conditions, thermal radiation, chemical reaction, Hall current and thermo-diffusion effects. Appropriate similarity transformations and analytical techniques are employed to reduce the system to a solvable form. A detailed parametric analysis is performed to evaluate the influence of key dimensionless parameters on momentum, heat and mass transfer characteristics. The results show that a 20% increase in suction reduces the near-wall velocity by 14.7%, while increasing the mechanical slip parameter by 0.3 enhances the wall velocity by 11.2%. Thermal slip decreases the surface temperature by 9.5%. Increasing the magnetic parameter from (M=1) to (M=3) suppresses the velocity field by 18.6% due to Lorentz forces. Thermal radiation enhances the temperature by 13.8%, whereas the Soret effect increases concentration by 16.4%. This work provides a unified quantitative assessment of slip, radiation and thermo-diffusive effects in MHD second-grade fluid flow, offering insights relevant to advanced thermal and energy engineering applications.