Abstract
Damping remains a hot-topic in design of offshore wind turbines as turbine and monopile sizes grow. For these new designs the contribution of fatigue loads in parked conditions have increased. In addition the larger impact of wave loads on XL monopiles has given wind wave misalignment a bigger role in fatigue in the cross-wind direction. Both fatigue mechanisms are linked by the absence of aerodynamic damping, with damping coming purely from the soil, the water and the structural steel.
For large monopiles any additional damping in the soil will thus have a beneficial effect on the fatigue life and ultimately the cost of the turbine. However, in contrast to its importance, the damping-contribution of the soil is only based on a best estimate and a limited amount of measurements. To bridge this knowledge gap OWI-lab has invested in monitoring campaigns on multiple operational wind turbines to determine damping. As a result OWI-lab currently has a database of thousands of damping estimates for different sites in the North-Sea.
In this contribution these results will be used to discuss the role of damping for offshore wind turbines. In particular we focus on the contribution of the soil to total damping. The variation of damping due to different soil conditions is made visible by looking at sideways (cross-wind) damping from different sites in the North-Sea.
For large monopiles any additional damping in the soil will thus have a beneficial effect on the fatigue life and ultimately the cost of the turbine. However, in contrast to its importance, the damping-contribution of the soil is only based on a best estimate and a limited amount of measurements. To bridge this knowledge gap OWI-lab has invested in monitoring campaigns on multiple operational wind turbines to determine damping. As a result OWI-lab currently has a database of thousands of damping estimates for different sites in the North-Sea.
In this contribution these results will be used to discuss the role of damping for offshore wind turbines. In particular we focus on the contribution of the soil to total damping. The variation of damping due to different soil conditions is made visible by looking at sideways (cross-wind) damping from different sites in the North-Sea.
Original language | English |
---|---|
Publication status | Published - 1 May 2017 |
Event | Offshore Wind Energy - London ExCel, London, United Kingdom Duration: 6 Jun 2017 → 8 Jun 2017 http://offshorewind2017.com/conference |
Conference
Conference | Offshore Wind Energy |
---|---|
Abbreviated title | OWE |
Country/Territory | United Kingdom |
City | London |
Period | 6/06/17 → 8/06/17 |
Internet address |