THERMAL PERFORMANCE ANALYSES OF WATER BASED CuO-TiO2 HYBRID NANOFLUID FLOW IN A HORIZONTAL TUBE

Year 2016, Issue: 4, 49 - 54, 01.12.2016

Toygun Dagdevır Veysel Ozceyhan

Abstract

In this study, a CFD modelling of a horizontal straight tube was carried out to investigate the effect of fraction of
hybrid water based CuO-TiO2 nanofluid on thermal performance. In the numerical analysis, in order to ensure
fully developed flow, the tested tube was adjusted, and uniform heat flux was applied on outer surface of the test
tube. Different turbulence models were examined and k-ω Shear Stress Transport (SST) turbulent model was
employed to simulate turbulent flow, and analyses were implemented for Reynolds number ranging from 10,000
to 50,000. The flow was simulated as a mixture model, and properties of nanoparticles and water are assumed as
not depends on temperature. Thermo-physical properties of nanofluid were calculated from commonly used
equations in literature. Nanofluid volume fractions (φ) in water were employed as 5, 4, 3, and 2% in which each
concentration has different volume fractions of CuO and TiO2. As a result, the higher volume concentration of
CuO compared to TiO2, the higher heat transfer coefficient was obtained. However, the highest effective Nusselt
number of 1.145 is obtained for volume fraction of CuO and TiO2 is 0.02 and 0.03, respectively at Reynolds
number of 50,000.

Keywords

hybrid nanofluid, convective heat transfer, numerical study