Numerical investigation on the effect of diamond-shaped turbulator on thermo-hydraulic performance of tube

Abstract

In this paper, thermo-hydraulic analysis of a diamond-shaped turbulator in a tube was investigated using the numerical simulation. Nusselt number and friction factor were evaluated by variation of Reynolds number in the range of 3500–16 500 and turbulator parameters including step ratio and rode diameter. Numerical validation was performed with experimental model and a good matching was observed. Then, closed form correlations for the Nusselt number and friction factor were presented with respect to Reynolds number. Numerical results revealed that a turbulator with a step ratio =1 and rod diameter = 3 mm provide the best Nusselt number. In addition, the results showed that the friction factor reduces by increment of both step ratio and rode diameter. Furthermore, by adjusting a turbulator with the new parameters, 40–56% improvement in the friction factor was noticed compared with the literature results. Then, by using definition of efficiency, the effect of both step ratio and rod diameter was investigated. The results revealed 4.60%–18.20% improvement in the efficiency for step ratio = 3 and rod diameter = 3 mm in comparison with the reported results in the literature. Finally, some correlations for Nusselt number and friction factor using the numerical results were presented with acceptable agreement.