Abstract
As the depths of sites consented for offshore wind increases, the need to develop floating foundations for wind turbines increases, as fixed foundations are only economically viable up to approximately 50 m water depth [2]. Key to developing the floating wind turbine industry is the development of accurate numerical models, which can combine the aerodynamic, hydrodynamic, structural flexibility and mooring components. Very little offshore data exists, however, in order to validate these numerical models.
Floating Power Plant are the developers of a floating, hybrid wind- and wave-energy device. The device uses the pitching wave energy devices, not only to increase and smooth the power output from the platform, but also to take the energy from the waves in a controlled manner, resulting in a stable platform for the wind turbine and a safe harbour for O&M. They are currently developing the final design for their first full-scale prototype, the P80, which has a width of 80 m. As part of the development, Floating Power Plant have completed 4 offshore test-phases (totalling over 2 years offshore operation) on a 37 m wide scaled test device, the P37.
This paper focuses on the comparison of one of the leading numerical models for floating wind turbines, developed by DTU Wind Energy, to the offshore data from P37. The numerical model couples DTU’s own aeroelastic code, HAWC2, with a special external system that reads the output files generated directly by the commercial wave analysis software, WAMIT.