Author(s): Virginia Rossi; Christian Tognacca; Riccardo Radogna

Linked Author(s):

Keywords: Morning Glory Spillway; Numerical Modeling; Validation through Prototype Measurements; Dam Safety

Abstract: The flood management system of the Malvaglia dam has undergone investigation via instationary 3D simulations conducted using OpenFOAM. Validation of the numerical model was successfully achieved through field measurements conducted by VAW. The primary objective was to delineate the discharge conditions of the system, comprising a surface discharge (a morning glory spillway) and two bottom outlets converging into the same pipe as the surface discharge, to determine the maximum discharge capacity of the system and assess potential enhancements to system safety. Simulations indicate that activation of the bottom outlets leads to at least partial stabilisation of outflow within the system. The significant instabilities observed in the outflow from the tunnel in situations without activated bottom outlets diminish notably with one bottom outlet in full operation and further decrease with both bottom outlets active. Additionally, in scenarios with both bottom outlets operational, negative pressures diminish until they are entirely absent under maximum load conditions (approximately 460 m3 /s).

DOI: https://doi.org/10.3929/ethz-b-000675921

Year: 2024