The Dynamic Response Of An Offshore Wind Turbine With Realistic Flexibility To Breaking Wave Impact

The effects of operational loads and wind loads on offshoremonopile wind turbines are well understood. For most sites,however, the water depth is such that breaking or near-breakingwaves will occur causing impulsive excitation of the monopileand consequently considerable stresses and displacements inthe monopile, tower and turbine. To investigate this, pilotmodel tests were conducted with a special model of an offshorewind turbine with realistic flexibility tested in (extreme) waves.This flexibility was considered to be necessary for two reasons:the impulsive loading of extreme waves is very complex andthere can be an interaction between this excitation and thedynamic response of the foundation and tower. The testsconfirmed the importance of the topic of breaking waves:horizontal accelerations of more than 0.5g were recorded atnacelle level in extreme cases.