Computational Fluid Dynamics Investigations of Breaking Focused Wave-Induced Loads on a Monopile and the Effect of Breaker Location

Abstract

The design of new offshore structures requires the calculation of the wave-induced loads. In this regard, the computational fluid dynamics (CFD) methodology has shown to be a reliable tool, in the case of breaking waves especially. In this paper, two CFD models are tested in the reproduction of the experimental spilling waves impacting a circular cylinder for four different wave impact scenarios for focused waves. The numerical and experimental free surface elevations at different locations around the cylinder are also compared to verify the both numerical models. The numerical results from the models are shown together with the experimental measurements. Both CFD models are able to model the impact forces with a reasonable accuracy. When the cylinder is placed at a distance of 0.7 m from the wave breaking point, the value of the measured wave impact forces is highest due to the overturning wave crest and air entrainment. The wave-induced impact forces decrease, when the monopile is placed at distances further away from the breaking location.