I am analyzing the NREL 5MW onshore wind turbine and want to find the loads for 1-year and 50-year recurrence in the DLC 1.1 as stated in IEC61400-1 (p. 35). I have read that one approach is to make a number of bins between the cut-in and cut-out wind speeds of the wind turbine (e.g. 2-m/s). Then it is necessary to run TurbSIM at least 15 times with different rand seeds for each bin and generate 15 separate 10 minute time series. After that the peaks of each 10 minute time series should be determined and an extrapolation can be done by applying a “3 parameter Weibull distribution function”.
Does anyone have hands-on experience with this with the output files generated by FAST or can you guide me towards relevant literature or software, which can be used?
Thanks in advance
Jacob K. Pedersen
University of Southern Denmark
I see this post has not been answered. I am curious if there are any NREL post-processing routines (or any other option) that can be used for FAST (ultimate) loads output and comply with IEC61400-1 ed.3. This would include:
Extrapolation of DLC 1.1 as Jacob mentioned
Determining characteristic value of ultimate loads (pg. 42)
Any insights on these post-processing direction would be greatly helpful.
MExtremes can be used to post-process ultimate loads for extreme events: nwtc.nrel.gov/MExtremes. MExtremes includes logic to select the mean value of the largest half of the maximum loads. However, while NREL has done a lot of research in loads extrapolation of DLC 1.1, NREL has not included this capability directly within MExtremes (or MCrunch) or otherwise released a public post-processor with this capability.
I was looking into load extrapolation of DLC1.1 to Vref and I found this thread. I would greatly appreciate it if someone has literature/documentation on how to proceed down this path that you can share with me.