A comparison of numerical simulations of breaking wave forces on a monopile structure using two different numerical models based on finite difference and finite volume methods

The nonlinear forces from breaking waves are a major concern in the design of offshore structures. Due to the complexity of the wave-breaking phenomenon, understanding the interaction of breaking waves with a structure is always a challenging task. The use of numerical models can be a useful tool for studying such a phenomenon. At present, many numerical models are available, using either a Finite Difference Method (FDM) or a Finite Volume Method (FVM), for solving the governing equations. In wave breaking studies, different researchers have come up with reasonable results, using both models. However, there have been few attempts to compare the relative strengths and weaknesses of the two methods. In the present paper a comparison of both methods applied to breaking wave studies is performed. Two different 3D Navier-Stokes solvers, 2PM3D (FDM) and OpenFOAM (FVM), are used to simulate the breaking wave forces on a monopile structure. Two different scenarios are considered for generating non-breaking and breaking waves, and the results are compared with theoretical results and available experimental measurements. For both numerical models, the breaking wave interactions with the monopile were in good agreement with the experimental measurements.