Entropy generation and forced convection analysis of ethylene glycol/MWCNTs-Fe3O4 non-Newtonian nanofluid in a wavy microchannel with hydrophobic surfaces on

Background: A three-dimensional simulation has been conducted to study the impact of the hydrophobicity of surfaces on heat transfer, hydrodynamics, and entropy generation of a non-Newtonian nanofluid in a wavy microchannel.Methods: The hybrid nanofluid is composed of ethylene glycol/MWCNTs-Fe3O4, and the wavy surface is under a constant heat flux. The main parameters that have been studied in this research are 10 <= Re <= 150, 1.25% <= phi <= 1.8%, and 0 <= beta* <= 0.1. The effects of the mentioned parameters during the research on velocity and tem-perature distribution, forced convection, pressure drop, and entropy generation have been investigated in detail. The outcomes indicated that using hydrophobic boundary conditions leads to an increase in heat transfer and a decrease in pressure losses, which is useful for the efficiency of cooling systems. The results also show that although increasing the volume fraction of nano-additives and Reynolds number leads to an increment in cooling, they also increase the pressure drop.Significant findings: The PEC and relative entropy generation results are studied for finding the optimized points.