# Doubts about 15 mw iea wind turbine **URL:** \ **Category:** Computer-Aided Engineering Software Tools\ **Created:** [April 4, 2024, 11:14pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773 "2024-04-04T23:14:25Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Alberto.Utrera](https://avatars.discourse-cdn.com/v4/letter/a/58f4c7/32.png) [@Alberto.Utrera](https://forums.nlr.gov/u/Alberto.Utrera)\ **Post date:** [April 4, 2024, 11:14pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/1 "2024-04-04T23:14:25Z")
Hi everyone, i have three doubts and i would really be grateful if you could help me with this: -Is it valid to do a simulation of 200 seconds with a DT of 0,05? I would like to put 0,005 but since i have to copy the table of the output file, i want to make it condense. However, is there a problem with these numbers i said? -About linearizing, what things could we obtain with it? -I am doing a final thesis for the upscaling from 15 MW WT to a 20 MW, focusing only on the RNA and tower (not on the floating or fixed platform). Apart from running simulations for both turbines with steady wind (from 3 m/s to 25 m/s) and turbulent wind, would you recommend adding more interesting things to my final thesis which can be done with openfast? I know there are many thought-provoking things i could get with openfast , but what ones would you say it is a must in openfast? Thanks ---
**Author:** ![Jason.Jonkman](https://dub1.discourse-cdn.com/nrel/user_avatar/forums.nlr.gov/jason.jonkman/32/3086_2.png) [@Jason.Jonkman](https://forums.nlr.gov/u/Jason.Jonkman)\ **Post date:** [April 4, 2024, 11:33pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/2 "2024-04-04T23:33:01Z")
Dear @Alberto.Utrera, Regarding your first question, as has been discussed before in several forum topics, the required time step (`DT`) of an OpenFAST simulation is dictated by the natural frequencies and excitation frequencies inherent in a model. You can always coarsen the OpenFAST output (via input `DTOut`) if you wish to have less output data than you’d get if you output every time step. The required length of a given simulation (`TMax`) is typically chosen to cover the core dynamic response of the transient or to capture statistical significance (when accounting for turbulence). 10 minute simulations are typical for wind turbine simulations for a given turbulent condition. Regarding linearization of OpenFAST, it is mainly useful for full-system eigenanalysis (to obtain full-system natural frequencies, damping, and mode shapes), controls design, stability analysis, and for generally “understanding” the system response. Best regards, ---
**Author:** ![Alberto.Utrera](https://avatars.discourse-cdn.com/v4/letter/a/58f4c7/32.png) [@Alberto.Utrera](https://forums.nlr.gov/u/Alberto.Utrera)\ **Post date:** [April 5, 2024, 3:33pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/3 "2024-04-05T15:33:45Z")
Thanks for the reply @Jason.Jonkman. In which file, could I be able to see the highest natural frequency in Hz of coupling between modules? In my simulation, I am using steady conditions and not turbulent. I am setting the Tmax to 200s. Although the trends of the majority of some parameters can be seen perfectly (because of the convergence), there are others that I do not know if the response will be damped or amplified. In this case, it is better for me to broaden the Tmax, right? br ---
**Author:** ![Jason.Jonkman](https://dub1.discourse-cdn.com/nrel/user_avatar/forums.nlr.gov/jason.jonkman/32/3086_2.png) [@Jason.Jonkman](https://forums.nlr.gov/u/Jason.Jonkman)\ **Post date:** [April 5, 2024, 9:20pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/4 "2024-04-05T21:20:40Z")
Dear @Alberto.Utrera, You can find the highest natural frequency (as well as any full-system natural frequency) through an OpenFAST linearization analysis, followed by Eigenanalysis. For the purposes of computed the highest frequency for identifying DT, you can choose simple conditions such as `CompAero` = 0 (in the OpenFAST primary input file) and `RotSpeed` = 0 (in ElastoDyn). When using steady inflow, presumably your objective is to find the steady-state condition. If the steady-state condition is not obvious after 200 s, you could increase `TMax`. Best regards, ---
**Author:** ![Alberto.Utrera](https://avatars.discourse-cdn.com/v4/letter/a/58f4c7/32.png) [@Alberto.Utrera](https://forums.nlr.gov/u/Alberto.Utrera)\ **Post date:** [May 20, 2024, 6:53am UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/5 "2024-05-20T06:53:44Z")
Hi @Jason.Jonkman, I am basing part of my final thesis on the methodology stated in the following thesis:([https://oaktrust.library.tamu.edu/bitstream/handle/1969.1/193162/WU-THESIS-2021.pdf?sequence=1&isAllowed=y](https://oaktrust.library.tamu.edu/bitstream/handle/1969.1/193162/WU-THESIS-2021.pdf?sequence=1&isAllowed=y)) Since i am doing an upscaling from the 15 MW IEA Wind turbine fixed in a monopile, could it be possible to use the aforementioned thesis (link attached) to upscale the 15 MW iEA? I am asking this question because the thesis is for floating platforms and the 15 MW IEA is fixed on a monopile. Thank u . ALbert ---
**Author:** ![Jason.Jonkman](https://dub1.discourse-cdn.com/nrel/user_avatar/forums.nlr.gov/jason.jonkman/32/3086_2.png) [@Jason.Jonkman](https://forums.nlr.gov/u/Jason.Jonkman)\ **Post date:** [May 20, 2024, 2:37pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/6 "2024-05-20T14:37:06Z")
Dear @Alberto.Utrera, I’m not familiar with the paper you reference. I recall reviewing the following the paper about scaling at one point: [https://www.researchgate.net/publication/258724726\_Upscaling\_wind\_turbines\_Theoretical\_and\_practical\_aspects\_and\_their\_impact\_on\_the\_cost\_of\_energy](https://www.researchgate.net/publication/258724726_Upscaling_wind_turbines_Theoretical_and_practical_aspects_and_their_impact_on_the_cost_of_energy), but that was a while ago. I’m sure there are other wind turbine scaling-related papers in the literature as well. Best regards, ---
**Author:** ![Alberto.Utrera](https://avatars.discourse-cdn.com/v4/letter/a/58f4c7/32.png) [@Alberto.Utrera](https://forums.nlr.gov/u/Alberto.Utrera)\ **Post date:** [May 20, 2024, 4:34pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/7 "2024-05-20T16:34:00Z")
Dear @Jason.Jonkman I also Saw that paper but unfortunately It does not apply to my specific case since i am dealing with AN upscaling from 15 MW to 20 MW. It would be comfortable if i had only to interpolate, but It is not the case. I have been reading papers such as Turaj Ashuri one , applying MDO. Anyway, the question IS wether i can make use of floating wind turbine parameters and apply them to monopile supported wind turbine parameters. Thank u. Albert ---
**Author:** ![Jason.Jonkman](https://dub1.discourse-cdn.com/nrel/user_avatar/forums.nlr.gov/jason.jonkman/32/3086_2.png) [@Jason.Jonkman](https://forums.nlr.gov/u/Jason.Jonkman)\ **Post date:** [May 20, 2024, 8:08pm UTC](https://forums.nlr.gov/t/doubts-about-15-mw-iea-wind-turbine/6773/8 "2024-05-20T20:08:48Z")
Dear @Alberto.Utrera, If you are referring to simple geometry scaling of a wind turbine, I would not think the scaling relationships would depend on the support structure. FYI: There is a new IEA Wind 22-MW RWT that has been developed in case you are interested: [GitHub - IEAWindTask37/IEA-22-280-RWT: Repository for 22MW offshore reference wind turbine developed by the IEA Wind Task 37](https://github.com/IEAWindTask37/IEA-22-280-RWT). Best regards,