Heat Transfer and Fluid Flow Over a Bank of Circular Tubes Heat Exchanger Using Nanofluids: CFD Simulation

Abstract

In the present work, the influence of the basefluids and nanoparticle types on the fluid flow and the heat transfer behavior were studied. Numerical investigation has been done over a bank of tubes heat exchanger in a triangular arrangement. Turbulent forced convection of Al2O3 and SiO2 nanoparticles-based water and glycerin nanofluids was predicted, spherical nanoparticles with a diameter of 30 nm and a volume fraction of 3% were assumed in this simulation. Commercial software so called Ansys fluent used as a computational fluid dynamics code to solve steady (2-D) Navier-Stokes and energy equations adopting finite volume techniques. The k-ε model was used to modelling the effect of turbulent. The obtained results demonstrated that the heat transfer for SiO2 nanoparticles based deionized water nanofluids was higher than the other types of nanofluids, which means that this working fluid could be promising cooling liquid in many heat exchange systems. The friction coefficient for all nanofluids reduced with increasing Reynolds number for all tubes. Furthermore, the results showed that the heat transfer enhancement increased with increasing the Reynolds number in all nanofluids with constant volume concentration and nanoparticles size.