A computational analysis of radiative bioconvection magnetohydrodynamic double diffusive Darcy-Forchheimer stagnation point flow of second-grade fluid with activation energy

Purpose This study examines the magnetohydrodynamic (MHD) flow of a double-diffusive second-grade fluid through a non-Darcy permeable medium via a vertical surface. It accounts for the effects of viscous dissipation, heat source, and Arrhenius activation energy in both opposing and assisting flow regimes under bioconvection flow. The research focuses on the complex interactions of hydrodynamic, thermal, solutal and microbial transport mechanisms, which are essential in bio-inspired fluid mechanics and energy systems applications. Design/methodology/approach Similarity transformations are implemented to decode the governing partial differential equations into a system of coupled ordinary differential equations. These equations are then numerically tackled using the MATLAB bvp4c technique. The study provides graphical and tabular analyses for velocity, temperature, concentration and microorganism profiles, along with local microbe count, local Nusselt and Sherwood numbers and the skin friction factor. Findings The consequences display that growing the second-grade fluid parameter enhances temperature and solute concentration but reduces speed in both helping and contrasting flow regimes. Higher activation energy leads to greater solute concentration, while increased bioconvection Lewis and Peclet numbers result in a decline in microorganism distribution. Originality/value The study presents a comprehensive investigation of double-diffusive second-grade bioconvective MHD flow in Darcy-Forchheimer permeable medium, incorporating combined effects of viscous dissipation, heat generation as well as Arrhenius activation energy. It confirms consistency with previous literature, validating the robustness of the present model and its relevance to modern bio-convective and energy-related fluid systems.