Author(s): Guodong Li; Tian Mi; Miao Ma
Linked Author(s):
Keywords: Piano Key Weir，Discharge capacity，Numerical simulation，Hydraulic characteristics
Abstract: The Piano Key Weir is a type of nonlinear (labyrinth-type) weir using overhangs to reduce the footprint of the foundation so that it can be placed directly on a dam crest. Together with its high discharge capacity under low heads, this geometry makes the weirs interesting in dam rehabilitation. However, the Piano Key Weir is a new weir type, first designed in 2001 and built beginning at 2006 by Electricite′e France. Although experimental studies confirmed its appealing discharge capacity, but their overflow feature need to be further investigation. This research presents numerical simulation results performed on a 1: 1scale model based on a experiment conducted by Indian National Committee on Hydraulics (INCH) Ministry of Water Resources, aims at determining the flow features along the weir, and their dependents on the upstream head. The CFD model selected for this study is the commercially available software FLUENT which simultaneously solves the three dimensional, transient Reynolds averaged Navier-Stokes equations on a structured or unstructured grid, capable of resolving complex geometries and boundaries. The volume of fluid (VOF) method is employed in FLUENT tracking fluid-air or fluid-fluid interfaces. By examining several turbulent models, this study recommends to use the RNG κ-ε model for simulating mean flow field over Piano Key Weir. It is found that the simulation results are reasonably consistent with those of the experimental measurements. Based on the study results, the nature of the flow structure, such as the height over the weir, the flow discharge, velocity and pressure distribution over a Piano Key Weir is analyzed.
Year: 2013