“Investigation on the use of a hybrid CFD solver to simulate breaking waves”
The wave breaking process generates a two-phase bubbly flow with length scales of different order of magnitude, from the free surface measurable in meters down to the entrapped air bubbles with size of a fraction of a millimeter.
A CFD model capable of handling such multi-scale problem is presented. The model is based on the solver “multiphaseEulerFoam” which combines the Eulerian multi-fluid approach for dispersed flows with a numerical interface sharpening method.
The model, with an implemented formulation for the breakage of bubbles, was first tested against experimental data of an air-water flow in a bubble column. Results were satisfying although the closure terms for the interaction between phases need further investigations. A laboratory solitary breaking wave was then simulated. The surface elevation variation and the run-up were in good agreement with the experimental data.