Numerical Simulation of Nonlinear Free Surface Water Waves Using a Coupled Potential Flow-Urans/Vof Approach

Abstract

Keywords: Nonlinear free surface water waves, One-way coupling of potential and viscous flow models, Focusing wave events, Waves on sloping bottom, Survey on wave models.Abstract. This paper first presents a comparison particularly in terms of accuracy between four nonlinear potential flow models for simulation of nonlinear free surface water waves. The performance of the wave models is compared in five test cases in 2D for which measurement data was also available. Three cases involved wave groups propagating over a flat bottom and producing a focusing event, and two cases involved irregular waves propagating over sloping bottom. After the comparison study, one of the potential flow solvers was selected for one-way coupling with a viscous flow solver. Details of this coupling are presented along with some information about the viscous flow solver in question. Here strong suits of both solvers are utilized to simulate nonlinear water waves in an accurate and efficient manner. Even though only simulating nonlinear waves is discussed in the paper, this work was considered as a stepping stone to later focus on hydrodynamic wave loading on structures and wave-structure interaction using this coupling. In the end results showed that such a coupling can indeed be a valuable tool to study wave motion. In all the simulations, comparison with the measurements demonstrated good agreement, and the convergence behavior of the coupled solver was acceptable.