Irreversibility analysis of Cu-TiO2-H2O hybrid-nanofluid impinging on a 3-D stretching sheet in a porous medium with nonlinear radiation: Darcy-Forchhiemer's model

The current research is conducted to investigate the slip effect and to analyze entropy production in both hybrid nanofluids, and common nanofluids flow past a convectively heated three-dimensional stretching sheet placed in a porous medium. The slip flow is considered in a Darcy-Forchheimer's scheme by incorporating the nonlinear thermal radiation. Water is taken as base fluid, while Copper and Titanium dioxide nanoparticles are considered. The governing models are overset into dimensionless variables using similarity transformation, and the solution is acquired numerically. The impacts of pertinent factors on the flow, heat transfer, and entropy generation rates are explored. Additional plot portraying the streamlines and isotherms for both nanofluids are presented to examine the hydrothermal behavior. Skin friction and heat transport are discussed with sensible judgment. A comparison with earlier studies is unwrapped to ensure the model's validity. The results communicate that temperature is enhanced with porosity, whereas velocity is found to be decelerated. Bejan number is decreasing with an increase in the nanoparticle volume fraction of nanoparticles. Furthermore, hybrid nanofluids generate less entropy than common nanofluids. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University.