Numerical Analysis of Reiner‐Rivlin Nanofluid Flow with Mechanism of Entropy Optimization and Exothermic/Endothermic Catalytic Reaction on a Cylindrical Surface

Abstract Nanofluids are employed in various heat transfer and cooling applications due to their enhanced thermal conductivity, making them valuable in electronics cooling, solar collectors, and heat exchangers. Tri‐nanofluids, which are the combination of three different nanoparticles, offer further optimization in applications such as drug delivery, enhanced oil recovery, and refrigeration systems, owing to their multifunctional and tunable properties. Therefore, the present research focuses on the magnetized convective flow of a Reiner‐Rivlin tri‐nanofluid around an extended cylinder, considering the influences of homogeneous–heterogeneous reactions, variable thermal conductivity, and entropy generation. The active nanoparticles employed in this study are silicon carbide (), silver (), and aluminum oxide (), immersed in ethylene glycol (), which serves as the base fluid. The bvp4c approach on MATALB is used to solve the dimensionless ordinary differential equations (ODEs), which are obtained after the necessary transformations applied to the mathematical flow model. The effects of various parameters on fluid flow, temperature, and homogeneous and heterogeneous reactions are investigated. It is observed from the results that fluid velocity increases with higher values of the Reiner‐Rivlin fluid parameter and curvature parameter. Furthermore, as the thermal relaxation time parameter increases, the fluid temperature decreases, and also homogeneous reaction parameter leads to a notable reduction in the species concentration.