Feature of metallic oxide nanoparticles in the thermal efficiency and flow structure of non-Newtonian homogeneous nanofluid: experimental data-based mathematical approach

Abstract

Nanofluids are innovativeheat transfer fluids with superior thermophysical properties and have numerous engineering applications in several necessary fields. Keeping this in mind, the flow characteristics of non-Newtonian nanofluids over moving flat surfaces are discussed. We use nanofluids that are synthessed by dispersing the nanoparticles SiO2, TiO2, and MgO with (20–30 nm, 60–70 nm), (30, 50 nm) and (20 nm, 40 nm) particle diameters, respectively, in ethylene glycol-based fluid, including 5%, 10%, 15%, and 20% nanoparticle volume fraction. Mathematical modeling is demonstrated by continuity, momentum, heat equations, and parameters of the rheological model are associated with the viscosity-shear rate relation that follows the experimental results. We consequently explore velocity and temperature profiles through graphs under the impact of distinct nanoparticle volume fractions and diameters. The heat transfer rate and shear stress at the wall are investigated under different nanoparticle volume fractions. Furthermore, we have investigated and understood the behavior of mass flow rate and momentum flux through displacement and momentum thickness parameters. The results revealed that velocity is decreased due to increased viscosity and deficiency in mass and momentum flow rates with the enhancement in nanoparticle concentration.