Simulating Turbsim generated LLJ using FAST

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Simulating Turbsim generated LLJ using FAST

Postby George.Elderfield » Fri Aug 23, 2019 10:10 am


My question is regarding the TURBSIM GP LLJ model and the coherent turbulence files generated and coupling them with FAST. Reading the various user guides I understand that when using the GP LLJ model the coherent turbulence is contained in the .cts file. In the TURBSIM user guide it says that Aerodyn v12.57 to v13 can read this file with the .bts file and add them together.

I'd like to simulate turbines experiencing a LLJ using FAST but understand that FAST uses inflowind for the wind files which doesn't seem to have the capability of reading in .bts .cts files to include the coherent turbulence in the wind field. I also see that aerodyn v15 is used in FAST v8 is there a previous version of FAST where I can use Aerodyn v13 and input the windfiles (.bts and the .cts)?

Alternatively would it be possible to manually write code that can sum the two .bts and .cts files and create a wind file that would be compatible with FAST (or Bladed) like .bts or .wnd?

Thank You


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Re: Simulating Turbsim generated LLJ using FAST

Postby Jason.Jonkman » Fri Aug 23, 2019 1:45 pm

Hi George,

The ability to superimpose the GP LLJ coherent turbulence files on top of the TurbSim full-field files is not supported directly within OpenFAST or FAST v8 (this feature was supported in FAST v7, which uses AeroDyn v13). However, you had asked in a prior forum topic (viewtopic.php?f=14&t=2342&p=13297) about superimposing the files and saving them into a single file for use in OpenFAST or FAST v8. As I mentioned in that forum topic, the CTWind tool can be used for that purpose.

Best regards,
Jason Jonkman, Ph.D.
Senior Engineer | National Wind Technology Center (NWTC)

National Renewable Energy Laboratory (NREL)
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