Dear @Jason.Jonkman ,
At present, I want to understand the flapwise and edgewise response of blade with the change of inflow wind speed. I am using the IEA-15MW wind turbine model and ROSCO controller. There have been many studies that have presented relevant results (such as the figure below), but the author seems to have not clearly described why such changes occur. For researchers, this seems like common sense and does not require special explanation, but I may lack relevant knowledge reserves.
The above results are from this paper（Qu X, Li Y, Tang Y, et al. Comparative study of short-term extreme responses and fatigue damages of a floating wind turbine using two different blade models[J]. Applied Ocean Research, 2020,97）
As shown in Figure (a), the wind speed gradually increases over time. For the flapwise response results (as shown in Figures (f) and (h)), with the increase of inflow wind speed, the response results show a trend of first increasing and then decreasing, which seems reasonable because pitch control occurs at high wind speeds. However, for the edgewise response (as shown in Figure (e) and Figure (g)), the response results also show a similar pattern, and when the wind speed is high enough (close to the cut-out wind speed), the response results seem to show a increase again (the phenomenon in the figure is not obvious). I don’t quite understand this phenomenon. In my opinion, the edgewise response should be more affected by non wind speed conditions such as gravity and centrifugal force. Could you please describe the flapwise and edgewise response of blade with the change of inflow wind speed and why this change occurs?
Thanks a lot!