A three-dimensional numerical study has been undertaken to investigate the interactions of solitary waves and a horizontal plate. Both cases of suspended and submerged rigid plates in water are considered. The large-eddy simulation approach has been adopted in this study, where the model is based on the filtered Navier-Stokes equations with the dynamic Smagorinsky sub-grid model being used for the unresolved scales of turbulence. The governing equations have been discretized using the finite volume method, with the air-water interface being captured using a volume of fluid method and the cut cell method being implemented to deal with complex geometry in the Cartesian grid. Numerical results have been presented the free-surface elevations and pressure on the horizontal plate. Detailed free surface profile, velocity fields and vortical structures in the vicinity of the plate are shown and discussed.
It is noticed that extreme waves will become more common in coastal and offshore region due to the impact of climate change. Wave-structure interaction is a key aspect in the safe and cost-effective design of coastal and offshore structures, and marine renewable devices. Understanding the characteristics of the extreme wave climate, its variability, and survivability is an important consideration for sustainable development of coastal and offshore infrastructure.
In order to roughly predict the hydrodynamic loads on structures, the Morison equation and potential flow theory (Ma, et al., 2015) have been widely used in the literatures. However, it is challenged to consider wave impact on the structures by using these two approaches during wave breaking, especially when there are splash-up and air entrainment.
With developments of CFD (computational fluid dynamics) and increases in computer power, recent models for studying wave-structure interaction, solve the Navier-Stokes equations coupled with a free surface calculation. Several methods have been developed by solving Navier-Stokes model by using mesh-based methods (Chen, et al., 2014; Hu, et al., 2016; Martínez Ferrer, et al., 2016a; Xie et al., 2017), or alternatively, meshless smoothed particle hydrodynamics (SPH) (Lind, et al., 2012) and the meshless local Petrov-Galerkin (MLPG_R) method (Ma, 2005).
