This study examines the flow, heat, nanoparticle volume fraction and microorganism transfer of a micropolar bio-nanofluid over a solid sphere in a Darcy porous medium, incorporating Newtonian heating, Stefan blowing, zero mass flux, and an induced magnetic field as key factors relevant to biomedical, energy, and industrial applications. A numerical approach is used to solve the governing nonlinear equations by employing nonsimilar transformations along with the Keller-box method and successive substitution scheme for a detailed comparative analysis. The effects of parameters such as the bioconvection Rayleigh number (Rb), mixed convection parameter (λ), velocity slip (N1), induced magnetic field (M), Stefan blowing (s), and Darcy number (Kp) are systematically explored. The results show that increasing λ enhances friction and microorganism density by 23%, whereas Rb increases microorganism concentration by 31%. The induced magnetic field reduces the thermal resistance, lowering the Nusselt number by 15%, and Stefan blowing increases microorganism concentration by 27%. Velocity slip is found to reduce friction by 19%, and non-similar solutions predicted up to 12% higher heat transfer rates than similar solutions, emphasizing the importance of considering non-similarity for accurate real-world modeling.
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