Comparative analysis of turbulence models in hydraulic jumps

Abstract

A numerical simulation of the incompressible multiphase hydraulic jump flow was performed to compare the interface prediction through the use of the three RANS turbulence models: k–ɛ, RNGk– ɛ and SST k–w. A three dimensional no submerged hydraulic jump and a two dimensional submerged hydraulic jump were modeled. Both the geometry and the mesh were created using the open source Gmsh code. The project\'s geometry consists of a rectangular channel with length and height differences between the two dimensional and three dimensional simulations. Uniform hexahedral cells were used for the mesh. Three refining meshes were constructed to allow to verify simulation convergence. The Volume of Fluid (abbr. VOF) method was used for treatment of the air-water surface. The turbulence models were evaluated in three distinct set up configurations to provide a greater accuracy in the flow representation. In the two-dimensional analysis of a submerged hydraulic jump simulation, the turbulence model RNG RNG k– ɛ provided a better interface adjust with the experimental results than the model k– ɛ and SST k–w. In the three-dimensional simulation of a no-submerged hydraulic jump the k–# showed better results than the SST k–w and RNG k– ɛ capturing the height and length of the ledge with a better fit with the experimental results.