Author(s): Esteban Aguilera, Oscar F. Jiménez

Linked Author(s):

Keywords: Spillway Design; Flow over Weir; Numerical simulation; OPENFOAM; Computational Fluid Dynamics;

Abstract: This work constitutes a first phase of the evaluation of a three-dimensional flow simulation program capable of simulating the flow on spillways. The chosen program is OpenFOAM, which is free, open source and developed under a finite volume discretization.
A standard Creager crest type geometry was evaluated, for which data of physical models are available in the literature in order to compare the results obtained with the CFD program. The effects of mesh sizes, turbulence models and proportional geometries were studied. Subsequently, for a single crest geometry, the slope of the upstream face and the height of the approach (P/H0) were varied, evaluating each case under different flow rates. There were evaluated around 840 simulation cases distributed between calibration and numerical evaluation cases.
The program showed good results for the flow profiles, pressures and discharge capacity for weirs with low arrival speed, up to P/H0 = 1.0. With the correct size and mesh geometry, most results are within few percent of the empirical measurements. Given the evaluated conditions and the type of dam studied, as well as good results for certain ranges, the program showed that is functional for design purposes.
This project had the limitation related to the number of cases, with substantial different geometries, simulated due to the time stipulated in the development of the project and the computational cost involved in the calculation times, which is closely linked to the computational capacities of the computers used for the simulation of the analyzed cases.

DOI: https://doi.org/10.3850/38WC092019-0998

Year: 2019