Author(s): C. Fernandez Gorostidi; D. Bacchiega; F. Romero; C. Fattor

Linked Author(s): Claudio Antonio Fattor

Keywords: Stilling Basin; Cavitation; Turbulence Intensity; Physical Modelling

Abstract: The design of gated spillways followed by a hydraulic jump stilling basin is a very usual project condition. In such cases, special attention is paid to high flow discharges, situations in which the most critical hydrodynamically conditions are usually present on the stilling basin or towards downstream. When the spillway must discharge low flows, the ideal operation from the hydraulic point of view is given by the symmetrical and uniform operation of all its gates, which is not always reflected in practice. In fact, there are specific antecedents of asymmetric or non-uniform operations of gates that led to the formation of vertical axis vortices and separation zones, both on the downstream faces of spillway piles and on dissipation elements such as chute blocks, baffle piers and dentated sill. These processes increase the levels of hydrodynamic solicitations and the risks of cavitation to more severe limits than those resulting from the uniform operation of the spillway for its maximum design flow. The aforementioned comments express the need to establish clear operation rules of the spillway and, in parallel, quantify the possible effects derived from eventual asymmetric operations, which are not recommended but would eventually happen during the operation of the works.

DOI: https://doi.org/10.14264/uql.2020.603

Year: 2020