Transient analysis of the slamming wave load on an offshore wind turbine foundation generated by different types of breaking waves

Abstract

In this study, a computational fluid dynamics model was employed to simulate the impact of a breaking wave on the foundation of an offshore wind turbine. The accuracy of the numerical simulation was validated in comparison with published experimental results for the Large Wave Channel (GWK) at Hannover, Germany. To understand the influence of the wave-breaking location on the monopile support structure, a series of shoaling waves with different spilling and plunging breaking wave types were considered in terms of the surf-similarity parameter (ξ0) and relative breaking distance (xb′). After processing the total wave load with an empirical mode decomposition method and a low-pass filter, the instantaneous nature of the slamming wave load generated by different breaking wave types was obtained. Subsequently, an exponential-type refined dynamic model was established to consider the characteristics of the filtered slamming wave load. ξ0 and xb′ were found to be dominant factors for the run-up phenomena, slamming characteristics, and wave-dependent parameters. The results demonstrated that these two coefficients can be applied to determine the nature of the run-up and slamming wave loads.