How to convert from WAMIT file to FAST input file (.1.dat)

Wind & Water Computer-Aided Engineering Software Tools
#1

Hello,

Thank you for your attention.
I’m studying a coupled response of TLP floating wind turbine. While doing a calculation in FAST, I found my WAMIT file from SESAM HydroD should be changed to the proper input file for FAST. Could you explain how to convert from WAMIT(1.dat and 3.dat) file to FAST input file?
Herein the files are attached.

Thanks.
Hailey.Seo
WAMIT_5S.3.txt (349 KB)
WAMIT_5S.1.txt (53.2 KB)

#2

In addition to above questions, could you please check some error messages like below;
It didn’t work although I have not changed any function in your sample files (Test23.fst) except time range from 60s to 1000s. I checked Test24 and Test25 for semi and spar works very well.

Timestep: 65 of 1000 seconds. Estimated final compleation at 16:17:32.

FAST_Solution : CalcOutputs_And_SolveForInputs:SolveOption2:InflowWind_CalcOutput : CalcOutput:IfW_TSF
FWind_CalcOutput [position=(-8.523, -19.844, 50.377) in wind-file coordinates]:Error: FF wind
array was exhausted at 65.35 seconds (trying to access data at 72.102 seconds).

FAST encountered an error at simulation time 65.338 of 1000 seconds.
Simulation error level : FATAL ERROR

Aborting FAST.

#3

Dear Hailey,

I haven’t looked at your files in detail, but the format of the WAMIT-generated output files (*.1, *.3, and *.hst for first order, etc.) needed by HydroDyn can be found in Chapter 4 of the WAMIT User’s Manual, available online: wind.nrel.gov/nwtc/docs/HydroDyn_Manual.pdf.

An error regarding the “FF wind array was exhausted” has been discussed many times on this forum e.g.: http://forums.nrel.gov/t/error-ff-wind-array-was-exhausted/1267/6.

I hope that helps.

Best regards,

#4

@Jason.Jonkman Dear Jason,

I want to convert the wind output of fast.farm in vtk format into bts format file, or output the wind data in bts format by fast.farm directly. Is there any way? Thank you in advance.

Best regards,
Liye

#5

Dear @Liye.Zhao,

I’m not aware of a script that will do exactly what you want. But there are scripts in the MATLAB Toolbox (matlab-toolbox/Utilities at main · OpenFAST/matlab-toolbox · GitHub) and Python Toolbox (python-toolbox/pyFAST/input_output at main · OpenFAST/python-toolbox · GitHub) that will get you part way there.

Please note that the FAST.Farm output in VTK format can be 4D, with 3 spatial and 1 time dimensions . However, the TurbSim BTS format is only 3D, with 2 spatial and 1 time dimensions. So, what you propose likely only makes sense if you output a plane of data from FAST.Farm, e.g., through NOutDisWindYZ and OutDisWindX.

Best regards,