Author(s): C. Torres; D. Borman; A. Sleigh; D. Neeve

Linked Author(s): Channel Yurico Rodriguez Torres, Andrew Sleigh

Keywords: CFD VOF; Free surface flows; Labyrinth weir; Scale effects; Scaled physical model

Abstract: In the present study the three dimensional (3D) Computational Fluid Dynamics (CFD) Volume of Fluid (VOF) isemployed to reproduce the complex hydraulic flows over a labyrinth weir and a spillway for two flow rates, 40and the Probable Maximum Flood (PMF) event of the scheme, 159.5The VOF method is implemented in two solvers: the open source platform OpenFOAM and the commercial CFD package ANSYS Fluent. Validation is undertaken by modelling the scaled physical model of the scheme. Prototype scale simulations of the two flow rates are conducted, and comparisons between predictions at the two scales are made. Overall the two solvers predict the prototype flows to be shallower and with higher velocities than those at model scale, but with these scale effects becoming less prominent for increasing flow rates. In the 40case the wave structures in the prototype present elongation compared to those at model scale. In the PMF case, the elongation also causes the wave structures to change in position further downstream of the channel. Work is currently underway with the modelling of further flow rates in order to investigate the discrepancies between scale and prototype simulations with increased detail and determine limits to minimise impact of scaling.

DOI: https://doi.org/10.15142/T38W7F

Year: 2018