Breaking wave impact loads on a cylinder: model-scale experimental measurements and wave simulations from the DIMPACT project

This database consists in force measurements induced by breaking waves impacting a segmented circular cylinder. The database also contains measurements and numerical results regarding the breaking waves generated for this study.  These results were obtained during the PhD thesis of Florian Hulin (see Florian Hulin. Experimental study of the hydrodynamic loads generated by breaking wave impacts on floating offshore wind turbines. Mechanics [physics.med-ph]. ENSTA Bretagne - École nationale supérieure de techniques avancées Bretagne, 2024. English. ⟨NNT : 2024ENTA0004⟩. ⟨tel-04709649v2⟩). The experimental set-up and methodology are detailed in section 2 . The numerical approach used to simulate the waves is described in section 3. The experimental conditions of the different experiments and the database organization are described in detail in appendices A and B. 

The force measurements are stored in the file named impacts.zip. The wave simulation results and the wave profile measurements are stored in the file named waves.zip.

Abstract of the PhD thesis:
Breaking wave impacts may be responsible for the most severe hydrodynamic loads encountered during the life time of a floating offshore wind turbine, and significant progresses are required to predict these loads with confidence. We aimed to experimentally identify the different parameters of the waves and of the turbine which influence the impact force and to quantitatively assess their importance. The experiments were carried out in the wave flume of Ifremer, Brest. A segmented circular cylindrical mockup was used to measure the loads generated by focused breaking wave impacts. We used a new methodology based on a set of accelerometers to compensate for the force signal oscillations induced by the vibrations of the mockup, which are triggered by the impulsive nature of impact. An important effort was devoted to the characterisation of the impacting breaking waves in terms of geometry, crest speed and breaking strength. They were measured using a video camera and modelled with a fully non-linear potential flow solver. We investigated the influence of  the breaking strength of the impacting waves, the distance between the breaking location and the front face of the cylinder, the tilt angle of the cylinder and the horizontal velocity of the cylinder during impact.