Bidimensional Numerical Model of the Hidraulic Jump Downstream of a Creager Spillway

Abstract

This work presents a two-dimensional model of a spillway profile, specifically that of the Salto Grande hydroelectric complex, which consists of a dam and a hydroelectric power plant. It is located in the middle course of the Uruguay River, about 15 km north of the cities of Salto (Uruguay) and Concordia (Argentina). At the foot of the spillway, there is a stilling basin where the energy of the flow is dissipated through a controlled hydraulic jump to mitigate potential erosion problems. The hydraulic jump is a rapidly varied flow, and its behavior cannot be characterized analytically. An alternative is to model the flow behavior through computational fluid dynamics (CFD). In this case, the Gmsh(R) application and OpenFOAM(R) were used complementarily. One to create the mesh, and the code to simulate the flow with an interFoam solution scheme: for two incompressible, immiscible thermal fluids using the Volume of Fluid (VOF) method to capture the interface. Different mesh resolutions and turbulence models were tested in the simulations to compare times, convergence orders, and results. These are compared with results published in recent literature to establish the appropriate resolution and the turbulence model that best approximates the evolution of the water-air interface and the velocity field in the hydraulic jump area.