Floating Offshore Wind Turbines

Floating offshore wind turbines (FOWT) are subject to complex static and dynamic loading. AS Mosley is currently developing a digital twin method for real-time monitoring of Floating Offshore Wind Turbines. The project is a collaboration between AS Mosley, Fugro and Strathclyde University and has been part-funded by The Carbon Trust and the Scottish Government through the Floating Wind Joint Industry Project (JIP). This JIP comprises of 14 leading offshore wind developers (EnBW, ENGIE, Eolfi, E.ON, Equinor, Innogy, Kyuden Mirai Energy, Orsted, ScottishPower Renewables, Shell, SSE, TEPCO, Vattenfall and WPD).

The digital twin will enable real-time tracking of fatigue damage on the mooring lines and other components. By monitoring the motions of the turbine using data loggers on the tower, the stresses in the mooring system can be calculated in real-time using a digital twin simulation model. This real-time technology is currently employed by AS Mosley on subsea wellhead systems with great success and we are excited to use our experience to significantly reduce or eliminate the requirement for visual inspection of the system below waterline. This has the potential to provide significant savings to the offshore wind industry.

Structural Integrity Assessments

AS Mosley offers structural integrity analysis of Floating Wind Turbine (FOWT) systems during the design stage. Floating offshore wind turbines are subject to complex static and dynamic loading. Our fully coupled time domain models are able to capture the complex loads, helping energy companies meet the requirements of IEC 61400-3-2 (design requirements for floating offshore wind turbines) or DNVGL-RP-0286 (coupled analysis of floating wind turbines).

Fig 1 – Floating Wind Simulation Model – Mooring Line Stresses

Our simulation models can provide energy companies with valuable insight at the design stage with outputs such as:

Resonant frequencies of the support structure at normal operating and extreme conditions
Amplitude of floating substructure surge, sway, heave, roll, pitch and yaw
Fatigue loading on mooring lines, umbilical, tower structure
Extreme loads (Axial, Bending, Shear) on mooring lines, umbilical, tower structure
Inclinations of floating wind turbine system
Effect of marine growth on system response
Effect of mooring line anchor slippage on system response

AS Mosley has over 24 years of experience in offshore simulation, ensuring that the loading and system response is fully understood. The detailed analysis performed by our engineers provides offshore energy providers with a prediction of the extreme loads and fatigue damage expected for the life of the floating turbine.