Influence of combined wave-current loading and scale effects on dynamically stable offshore monopile scour protections 

01 January 2016 → 31 December 2019
Research Foundation - Flanders (FWO)
Research disciplines
  • Engineering and technology
    • Geotechnical and environmental engineering
    • Marine engineering
costs Renewable energy foundation
Project description

Offshore wind farms contribute significantly to the contemporary renewable energy production. By positioning structures in an offshore environment, new technical design challenges arise. One of the main challenges is the optimisation of the foundation of offshore monopile turbines which represents one third of the total construction costs. To diminish this cost more fundamental insight in the behaviour of the expensive scour protection around a monopile is needed. A statically stable design approach is currently used (no stone movements) which results in large, difficult to place stones. New insights in the behaviour of scour protections could lead to a concept in which a prescribed movement of the stones would be allowed which would lead to a cheaper and easier to place structure. The research will be carried out by using two experimental facilities (wave flume and wave tank) and a numerical wave flume in OpenFOAM. New experimental tests will focus on the dynamic stability of the scour protection (damage initiation and evolution), by extending the parameter ranges (water depths, current and wave conditions) beyond known limits. In the wave tank, model effects, scale effects and 3D effects will be investigated. Numerical modelling using the same scale model set-up will provide additional data and insights, achieving an integrated research approach on the scouring processes. A novel scale distortion methodology, remediating for the observed scale effects, will be developed.