Author(s): S. Sun; X. Leng; H. Chanson

Linked Author(s): Shuangke Sun, Hubert Chanson

Keywords: Tainter gate; Rapid opening; Transient flow motion; Turbulence; Free-surface motion; Physical modelling; Desilting

Abstract: In water supply channels, the brusque operation of control gates may induce large unsteady flow motion called surges. Such an operation may be conducted to scour silted channels and sewers. Herein a physical study was conducted under controlled flow conditions to study the turbulent mixing upstream of a rapidly opening/closing tainter gate. The data suggested that the negative/positive surge generation was associated with large instantaneous free-surface fluctuations. The velocity measurements indicated significant variations in longitudinal velocity during the surge generation, as well as large fluctuations of all velocity components. The processes were associated with large Reynolds stress levels. The successive rapid closure and opening of undershoot tainter gate provided optimum conditions to scour silted canals, and the present results gave some detailed insights into the physical processes.

DOI: https://doi.org/10.14264/uql.2014.27

Year: 2014