SAFEMILLS · Increasing safety of offshore wind turbines operation: Study of the violent wave loads

The use of offshore wind turbines in coastal zones is the most promising method for clean energy production from the environment. Theyamplify the advantages of land based turbines due to the greater wind potential in the unprotected coasts and the vast areas of coastlines,whilst, in addition, avoid the disadvantages associated with deep water installations at the open sea (e.g. wind turbines mounted onTension Leg Platforms) such as difficult accession, costly maintenance, lengthy cabling etc. Shallow water installations however involve asignificant risk that originates from breaking wave trains at decreasing depths. This is the only devastating impact which might threaten theintegrity of the pillars and hence it must be properly investigated. Wind turbine pillars can be considered as slender structures, thehydrodynamics of which for years has been investigated by simplistic methods, such as Morison’s formula that was developed in fifties andadmittedly is not valid always. The existing studies often ignore the all-important violent impact due to breaking waves. The present projectaims at enhancing the existing state-of-the-art by proposing the deep and comprehensive investigation of the three-dimensional waterimpact problem for vertical wind turbine pillars using approaches such as Wagner’s theory and the steep wave slamming concept. The goalof the involved scientists is to extend the research on the task by considering alternative structural bases for wind turbines such as trusstype structures which further enhance the advantages of offshore wind turbines due to the lower construction cost, easier removal, repairand maintenance, increased safety, accession of deeper fields etc. To this end, a novel approach will be adopted that relies on theslamming impact on perforated structures. The expected theories, formulations and solution methods will be generic and in that sense willbe versatile allowing their employment to a range of water impact problems.