Numerical investigation of heat transfer of nanofluid flow inside helical tube with two-phase mixture model

Numerical simulation of developing laminar flow and heat transfer behavior of Al2O3/water nanofluid through helical tube is performed in this study. Two-phase mixture model with temperature dependent properties for water and nanofluid is used and validated against experimental data in the literature. Simulations is carried out for various nanoparticle volume fractions and Reynolds numbers. The variations of local heat transfer coefficient along the tube length from the inlet of tube is shown. The overall heat transfer enhancement for nanofluid in comparison with water is indicated. The results show that at the same nanoparticle volume fraction, the higher heat transfer enhancement related to water is observed at lower Reynolds numbers.