Magnetohydrodynamic stagnation flow of Al2O3–Cu–TiO2/H2O ternary nanofluid across a stretching/shrinking cylinder in the presence of nonlinear radiative heat and Arrhenius energy

Abstract

The stagnation flow in a ternary hybrid nanofluid towards a cylinder that stretches and shrinks with suction velocity is investigated in this work. Here, water serves as conventional fluid and the nanoparticles are titanium dioxide (TiO₂), copper (Cu), and alumina (Al₂O₃). This work aims to study the flow behaviour for velocity, concentration, and temperature including the novel effects of heat radiation in energy equation and energy activation in concentration equation. Using proper similarity variables, governing equations are transformed to dimension-free form. The bvp4c method is used to solve these nonlinear dimension-free equations numerically. The flow behaviour of various physical parameters is studied graphically for velocity, temperature, and concentration boundary layer. Moreover, considerable importance in this investigation are skin friction coefficient, mass transport rate, and heat transport rate. Observation reveals that Reynolds number and suction parameter enhance fluid velocity and skin friction. Also, fluid velocity in the case of ternary hybrid nanofluid, i.e., for Al₂O₃–Cu–TiO₂/H₂O enhances than hybrid nanofluid (Al₂O₃–Cu/H₂O) and nanofluid (Al₂O₃/H₂O). The temperature profile and heat transport rate are improved by heat sources. Increasing the radiation parameter reduces fluid temperature by 4.76% from ternary to hybrid nanofluid and 4.54% from hybrid to nanofluid. Chemical reaction and Schmidt number reduce concentration boundary layer. This mathematical modelling of nanofluid with stretching/shrinking cylinder can benefit society through applications in some processes such as polymer sheets, crystal mass production, metal extrusion, bath cooling, and plate cooling.