The influence of temperature on physical properties of a hybrid nanofluid flow in a non-Darcy porous medium

Abstract

The purpose of this paper is to debate the influences of variable thermal conductivity as well as viscosity on a hybrid nanofluid flow through a non-Darcy porous medium along a wavy surface. Two kinds of base fluids are considered; the first is water (H2O) with [Formula: see text] and the second is ethylene glycol–water mixture (C2H6O[Formula: see text]H2O) with [Formula: see text]. Furthermore, the physical properties of the base fluid have been modified via the addition of two kinds of suspended nanoparticles. The suspended nanoparticles of alumina Al2O3 were firstly added to the base fluid. Then, titania TiO2 suspended nanoparticles are immersed into this nanofluid to form two hybrid nanofluids (TiO[Formula: see text]Al2O3/H2O) and (TiO2-Al2O3/C2H6O2–H2O). Dupuit Forchheimer model as a non-Darcy porous medium is utilized. The mathematical model for the present physical problem with convective boundary condition is studied numerically via the Chebyshev pseudospectral (CPS) technique. Nusselt number, velocity and temperature profiles are investigated under different parameters. The present outcomes clarify that adding the alumina nanoparticle supports and improves the efficiency of the titania nanoparticle. Also, taking both of the hybrid nanofluid viscosity/thermal conductivity as variable functions of temperature has an important role to support the studies of heat transfer.