Numerical solutions of flow and heat transfer of Zn–TiO2/H2O hybrid nanofluid with microorganisms on an inclined shrinking plate

This study investigates the flow and heat transfer of a Zn−TiO2/H2O hybrid nanofluid with motile microorganisms over an inclined, shrinking plate. It considers the effects of heat source/sink, magnetic fields, non-linear radiation, and velocity slip conditions, using the governing equations for steady, incompressible fluid flow, along with heat and mass transfer. MATLAB's BVP4C solver is used to solve the governing partial differential equations numerically once they have been transformed into dimensionless ordinary differential equations using appropriate similarity transformations. The research identifies dual solutions, revealing distinct behaviors in velocity, temperature, nanoparticle, and microorganism concentration profiles. The suction parameter enhances velocity in the first solution by thinning the boundary layer but reduces it in the second, simultaneously lowering surface concentrations. The magnetic field decelerates flow and reduces concentration in the lower branch because of Lorentz forces acting against motion while accelerating flow and increasing concentration in the upper branch. Inclination angle raises velocity and temperature in the upper branch but reduces both in the lower branch. Thermal radiation, Eckert number, and temperature ratio parameter elevate temperature, while heat sinks lower it by improving heat dissipation. Higher Schmidt numbers and chemical reactions reduce nanoparticle concentration, whereas Peclet and bioconvection numbers diminish microbial concentration near the surface. These results enhance our understanding of hybrid nanofluid bioconvection under radiative and magnetic impacts and have applications in solar power generation, thermal exchangers, cooling appliances, and microbiological systems for effective thermal and mass transfer.