Optimización del comportamiento de estructuras hidráulicas complejas a través de modelación física. Caso estudio: vertederos tipo laberinto y abanico.

Abstract

Labyrinth and fan spillways are complex structures, presented as an alternative to regulate water levels and increase the discharge capacity of high demanding structures in comparison to the possibilities offered by frontal spillways with standard crest. However, due to its complex flow characteristics, it is difficult to achieve an optimum design of these structures based only on the current literature. Hence, physical modelling arises to provide innovative solutions to complex hydraulic problems, as well as, to produce the basis of new knowledge. This study aims to optimize behavior of special hydraulic structures for PACALORI project using physical modeling, specifically, labyrinth and fan spillways cases. With this objective, three physical models were built using a non-distorted scale under Froude’s similarity: a fan spillway at scale 1:30 and two labyrinth spillways at scale 1:45. The results obtained, allow qualitatively to evaluate the complex 3D-flow characteristics produced and to optimize the hydraulic components of each structure by a trial and error of different alternatives. Results from the experimental analysis contributed to determine a range of variation for the discharge coefficient (Cd) for fan spillways between 2.06 and 2.15 for 0.3 < H/Hd <1.0. On the other hand, experimental results for labyrinth spillways showed that Darvas model (1971) is more accurate to estimate the discharge coefficient (Cd) when the nappe breakers upstream and downstream of labyrinth weirs vertex are used. Furthermore, experiments showed that discharge capacity is reduced without the separating stacks, given that the effective length decreases, for this case, the discharge coefficient can be safely estimated using models referred by B. M. Crookston (2010) and Bilhan et al. (2016). Although the current study contributes to the knowledge for further designs for fan and labyrinth spillways, it also highlights the importance of experimental validation and therefore, it is recommended to verify the hydraulic behavior of these structures by a physical modeling.