Bioconvective prandtl hybrid nanofluid flow over a rotating stretching sheet with activation energy

Hybrid nanofluids have attracted considerable attention for advanced thermal-management applications because of their enhanced heat-transfer characteristics compared with conventional single-particle nanofluids. This study investigates magnetohydrodynamic (MHD) flow and heat and mass transfer of a Prandtl hybrid nanofluid containing zinc (Zn) and aluminium oxide (Al₂O₃) nanoparticles suspended in water over a stretching surface embedded in a porous rotating medium. The model incorporates the combined effects of magnetic field, porous resistance, rotation and Coriolis forces, inertia, suction, thermal radiation, chemical reaction, activation energy, and gyrotactic microorganisms. The governing nonlinear partial differential equations describing momentum, energy, concentration, and microorganism transport are transformed into a coupled system of nonlinear ordinary differential equations using appropriate similarity transformations. The resulting boundary-value problem is solved numerically in MATLAB, and the computed solutions are evaluated in terms of velocity, temperature, concentration, and microorganism-density distributions, together with the skin-friction coefficient and Nusselt number. The results demonstrate that variations in the magnetic, rotation, porosity, inertia, and suction parameters substantially modify the flow and transport characteristics, while thermal and mass-transfer responses are strongly influenced by the activation-energy, chemical-reaction, and thermal-radiation parameters. The quantitative changes in the skin-friction coefficient and Nusselt number further demonstrate the sensitivity of the system to these controlling parameters. As [Formula: see text] increases from 0.4 to 1.6, the hybrid nanofluid transfers approximately 38.7-39.9% more heat than the mono nanofluid. The results provide a numerical framework for assessing coupled MHD, thermal, chemical, and bioconvective transport in hybrid-nanofluid systems and may support the design and optimization of porous thermal-management configurations. A schematic compares two working fluids: a nanofluid made from water and zinc nanoparticles, and a hybrid nanofluid made from water, zinc, and aluminum oxide nanoparticles. A separate schematic depicts zinc and aluminum oxide nanoparticles in a fluid over a stretching surface, with a magnetic field and coordinate axes.