SPH numerical computations of wave impact onto a vertical wall with experimental comparisons

Abstract

In order to assess wave impacts on coastal structures that are coupled with a marine energy device, for instance an oscillating water column (OWC), a smoothed particle hydrodynamics (SPH) software named JOSEPHINE (Cherfils et al., 2012) is used. In the present study, only a vertical wall will be considered as the front wall or draft of an OWC. In order to clearly identify impact phenomena, a breaking solitary wave will be used, so as to have a single phenomenon. And comparisons with experimental results issuing from Kimmoun et al. (2009) will be used as a matter of validation of our numerical study on solitary wave impacts.The present paper will focus first on the accuracy and convergence of wave propagation within the SPH framework, as a continuation of the work of Antuono et al. (2011), both for a regular wave train and for a solitary wave. For regular waves, the second-order dispersion relation is well recovered, up to the third order for the higher amplitudes. For solitary waves, comparisons with analytic and experimental results are also performed.Several types of impact are obtained similarly to those mentioned in the literature by changing the wave-maker parameters or the water depth in numerical wave flume. However, most of the effort was used for the validation of an impact case well documented in the literature. New experimental results issuing from the previous study of Kimmoun et al. were also used. Some intense and rapid impact phenomena are reproduced with our SPH single-phase numerical approach. The conclusion of this work is that a two-phase compressible approach is finally necessary to accurately compute such phenomena.

Keywords

• Smoothed particle hydrodynamics
• Pressure impact
• Solitary wave
• Weakly compressible approach
• Propagation