Numerical Simulation of Water as Base Fluid Dispersed by Al2O3 Aluminum Oxide Nano-Sized Solid Particles with Various Concentrations

Abstract

Curves of pressure, lines of current, speed of fluid, fields and diagrams of kinetic energy, and plots of viscosity through a H2O/Al2O3 nanofluid-heat exchanger with recirculation promoters are studied by using a computational approach and a two-dimensional algorithm. The simulation used four nanofluid fractions, i.e. ϕ = 0.5, 1, 2 and 4 percent, with four flow rates, i.e. Re = 5, 10, 15 and 20 (× 103). Both the discontinuous-type deflectors and the detached-model bars are considered to reinforce the nanofluid field structure. The discontinuous-situation of these deflectors allows reducing the pressure on its front-corner by passing the fluid between their internal surfaces. In addition, the field is detached from the front-sharp-edge, forcing the creation of recycling-rings on their back-areas. While, the presence of the detached-bar model in both the top and the lower stations of the exchanger allows an improvement in the flow disturbance across the gaps through their interior-surfaces, and the formation of new recycling-cells near their right-sides. These vortices constitute opposite-currents where their strength increases with increasing nanofluid concentration and Reynolds values.