CFD analysis of using umbrella shaped turbulators to improve heat transfer in a horizontal pipe

Year 2022, Volume: 6 Issue: 1, 30 - 34, 15.07.2022

Ahmet Numan Özakın

Abstract

Heat transfer in pipes has an important place in the industry. For this purpose, many studies have been carried out toinvestigate the effects of elements with different geometries placed in the pipe on the heat transfer characteristics. In this study, the effects of umbrella-shaped turbulators with different angles (45o, 60o and 75o) on the heat transfer characteristics,placed in a horizontal pipe with a constant 20000 W/m2 heat flux from its surface, were investigated numerically. When the results of the study were examined, it was determined that the heat transfer was higher in cases where the umbrella opening was higher than in other cases. The maximum Nusselt number obtained in the study was determined to be 171.25 in the case of the 45 degree turbulator and 15000 Reynolds number. In addition, it was concluded that turbulent kinetic energy is an important parameter inincreasing the heat transfer.

Keywords

Heat transfer enhancement, Pipe heat transfer, Flow inserts, CFD

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