Numerical study on effect of oscillation center position on heat transfer and flow internal tube

Three-dimensional flow and convective heat transfer was modelled and was discreted by FVM to investigate the effect of oscillation center position on heat transfer and flow internal a smooth round tube in the present study. The heat transfer performance was measured by Nusselt number and flow capacity was measured by Darcy friction factor. The numerical results showed that heat transfer was enhanced and the enhancement increased with increase in the distance between oscillation and inlet. More over the fluctuation of Nu increased as the distance between oscillation and inlet increased. However, flow resistance was lower than static tube when oscillation center at the first half of tube and higher than static tube when oscillation center at the second half of tube including center point. In addition, the secondary flow and radial velocity was created by oscillation motion, which was the reason why heat transfer was enhanced. (C) 2019 Elsevier Ltd. All rights reserved.