Role of exothermic reaction, volumetric heat generation and thermal radiation on magnetized hybrid Ellis nanofluid flow over a solid sphere

Abstract

Purpose-The current study aims to investigate the effects of volumetric energy generation, magnetic fields and Ellis Ternary hybrid (silver, titanium oxide and graphene oxide in sodium alginate) nanofluid rheology over a solid sphere. The model consists of induced exothermic reactions, volumetric energy generation, radiative surface heat flux and convective boundary conditions. Design/methodology/approach-The strongly coupled nonlinear partial differential equations are nondimensionalized with the help of appropriate similarity variables. The formulated nonlinear differential equations are solved using the spectral Chebyshev collocation methods. The skin friction and Nusselt number are compared with the literature for various values of the mixed convection parameter, and agreement is observed. Findings-The key findings reveal that the induced exothermic reaction strength decelerates all the fluid fields, except the Nusselt number, while the reaction rate enhances the fluid velocity, temperature, skin friction, Nusselt number and Sherwood number by boosting the buoyancy forces, de-escalating boundary layers and steepening wall gradients. The Biot number accelerates the fluid profiles but decelerates the concentration. The fluid temperature and skin friction also drop with the internal heat generation parameter, while the velocity, nanoparticle concentration, Nusselt and Sherwood numbers improve, indicating that flow acceleration-driven convective cooling has the tendency to dominate over volumetric heating. Originality/value-The ternary hybrid nanofluid system demonstrated superior heat and mass transfer performance compared to mono and binary nanoparticle systems, as shown by broader intensity ranges and steeper gradients in contour and isotherm plots. This enhancement is due to the synergistic improvement of thermophysical properties, indicated by higher Nusselt and Sherwood numbers.