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Dear @niay000, I haven't spent much time reviewing your files, but the position stated in the error is well outside your stated TurbSim domain size, in both the Y and Z directions. If you specified your turbine geometry correctly, it sounds like your TurbSim domain size is sufficient for the undeflected geometry, but the deflection is very large. Are you receiving warnings about large blade or tower deflection? If so, I would assume your model is numerically unstable for some reason, e.g., due to incorrect scaling of mass/stiffness or too large of a time step. Best regards, |
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Dear All,
I hope this message finds you well.
I am trying to run OpenFAST for a scaled wind turbine model (model-scale wind tunnel experiment).
In this setup, the tests are conducted under 50-g gravity, so gravity is scaled accordingly (×50), and the time is scaled down to 1/50.
When the model-scale dimensions are converted back to the actual full-scale turbine size for calculation,
OpenFAST runs successfully; however, running the simulation at the model-scale dimensions produces the following error.
FAST_Solution:FAST_AdvanceStates:SolveOption2c_Inp2AD_SrvD:InflowWind_CalcOutput:CalcOutput:IfW_FF
Wind_CalcOutput [position=(1.9735, 0.94676, 1.3323) in wind-file coordinates]: FF wind array
boundaries violated. Grid too small in Z direction (Z=1.3323 m is above the grid).
All the input files (ElastoDyn, AeroDyn, InflowWind, case.fst) were scaled consistently with the model size.
What I Tried
In the past, when encountering similar errors, I was able to avoid them by using a much smaller analysis time step (DT).
This time, however, even with extremely small and practically infeasible DT values, the error still occurs.
Additionally, I tried significantly expanding the BTS file grid to cover a wider spatial range, but the error was still not avoided.
BTS File Information
The .bts file was generated using PyConTurb, with the following properties:
• Time steps: 18,192
• Spatial points: 1323
• Time range: 0.0 – 3.6382 s, with Δt = 0.0002 s
• Velocity ranges:
o u component: 5.44 – 5.99 m/s
o w component: 0.0054 – 0.0059 m/s
o No NaN values
• Grid dimensions:
o k points: 3 (u, v, w)
o y points: 21
o z points: 21
• Coordinate ranges:
o Hub height: 0.529 m
o Y: −0.469 → +0.469 m
o Z: 0.06 → 0.998 m
o X: 0.0 → 0.0 m (constant)
• Example samples:
o Y: [−0.469, −0.4221, −0.3752, …, 0.469]
o Z: [0.06, 0.06, …, 0.998]
o X: [0.0, 0.0, …, 0.0]
o
The model-scale setup is defined as follows:
• Water depth: 0.1 m
• Blade length: 0.115 m
• Blade chord: 0.06 m
• Hub height: 0.529 m
• Transition piece: 0.06 m
•
Questions:
・Is it possible to perform a simulation analysis of a model-scale wind turbine under such a gravity field?
・Do you have any advice for resolving these errors?
Please find attached the files I am using. For the purpose of attachment, I have changed their extensions to .txt.
I may be misunderstanding something fundamental, so please let me know if I should provide more details.
Thank you very much for your time and assistance.
Best regards,
casefst.txt
caselog.txt
inflowwind.txt
servodyn.txt
subdyn.txt
aerodyn.txt
aerodyn_blade.txt
elastodyn.txt
elastodyn_blade.txt
elastodyn_tower.txt
expfoil_plate_coords.txt
expfoil_plate.txt
hydrodyn.txt
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