Species concentration characteristics in autocatalytic chemically reactive nanofluid at 20 °C

This study examines the heat transfer (HT), flow and species concentration features of a titanium dioxide-water nanofluid past a circular porous slider at 20 °C. The problem is considered in the presence of heat generation/absorption, nonlinear thermal radiation, a magnetic field and homogeneous-heterogeneous chemical reactions. The three effective viscosity models and three thermal conductivity models are included for comparison to understand how the thermophysical-property correlations and particle morphology affect the prediction of the transfer properties. The resulting nonlinear system is numerically solved with the fourth-fifth order Runge-Kutta-Fehlberg method, and the Taguchi method is used to determine the relative importance of the selected controlling parameters in terms of the HT response. The statistical results show that the heat generation/absorption parameter contributes 59.27% to the HT variation for the nanolayer thermal conductivity model, making it the major contributing factor among the investigated parameters. The optimum HT rates for the nanolayer, Maxwell spherical and Hamilton-Crosser models (H-CMs) are 0.7683, 0.7745 and 0.7748, respectively. The results also show that the H-CM gives the highest predicted HT rate among the three thermal conductivity models. The present study is mainly presented by developing a combined evaluation of viscosity models, thermal conductivity models, particle morphology, chemical reactions and statistical optimization for flow over a circular porous slider, which provides a unified framework for the study of their effects on HT behaviour. Clinical Trial: Not applicable.