Thermo-Hydraulic Phenomena of Water-Al2O3 Nanofluid Flow Over a Rectangular Channel with Trapezoidal Obstacles

Abstract

Numerical simulations of water-Al2O3 nanofluid flow in a rectangular channel with two trapezoidal obstacles have been studied, which has rmarkable effect in various engineering applications. The governing equations have been solved using SIMPLEC algorithm and FLUENT software has been used to visualize the simulation results. Motivation of this work is to examine the dynamic behavior of laminar water-Al2O3 nanofluid flow for volume fraction, ψ = 0%, 2%, and 4%. The present study analyzes different hydrothermal flow phenomena with the variation in obstacle height and ψ. Moreover, the simulation results, such as the profiles of velocity, normalized temperature (θ), poiseuille number (CfRe), local Nusselt number (Nu), average Nusselt number (Nuavg) and friction factor (f) have been portrayed with the variations in ψ and Reynolds number (Re). It has been observed that the obstacles increase the convective heat transfer (HT) significantly. At Re = 100, for all the configurations it has been found that the velocity profile become more pronounced for ψ = 4% as compared to ψ = 0%. A linear relationship has been found between the values of f and ψ. It is also found that an increase in Re increases vortex length. It is also shown that variation of volume fraction (ψ) and obstacle height resulted in an indicative change in the normalized temperature and velocity along the center line. In type-1 obstacle configuration, it has been found that Nuavg increases by 6.6% at ψ = 2%, and the same increases by 10.73% at ψ = 4% as compared to that at ψ = 0%. Moreover, it has been found that in type-2 obstacle configuration, value of f increases by approximately 7.9% at ψ = 2% and 13.84% at ψ = 4% as compared to that at ψ = 0%.