FAST.Farm

Topics of general, but wind-related interest.

Moderator: Bonnie.Jonkman

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Tue Oct 20, 2020 6:31 am

Dear Deza,

A paper we wrote titled, "FAST.Farm Development and Validation of Structural Load Prediction Against Large Eddy Simulations" was recently accepted for publication in the Wind Energy journal. Included in that paper are quantitative comparisons between FAST.Farm and high-fidelity coupled SOWFA-OpenFAST simulations in terms of percent error of mean and standard deviation values for the structural outputs (deflections and loads) of several wind turbines. I gather this is what you are looking for. The publishing process is underway and should be available soon.

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

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Leire.Gandiaga
Posts: 3
Joined: Fri Feb 28, 2020 12:36 am
Organization: Tekniker Research Centre
Location: Spain

Re: FAST.Farm

Postby Leire.Gandiaga » Tue Oct 20, 2020 10:42 am

Dear Jason,

Could you please send to me the pre-release of the fast.farm software together with its documentation? Do you have an approximate date for the official release?

Thanks a lot,

Leire

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Tue Oct 20, 2020 12:14 pm

Sent.

We are working on the official release of FAST.Farm and expect it to be soon, but I don't want to state a date because I've been wrong so many times before.

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

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Jiaping.Cui
Posts: 18
Joined: Tue Aug 25, 2020 1:16 am
Organization: Shenyang University of Technology
Location: China

Re: FAST.Farm

Postby Jiaping.Cui » Wed Oct 21, 2020 12:38 am

Dear Jason,

Thank you for your explanation patiently, that solves many my doubts.

I scan the FAST.Farm User's Guide and Theory Manual, and I found that the primary input .fstf file have a few changes, so if the pre-version FAST.Farm have a update ? If have, I hope I can get the lastest pre-version and better also the lastest sample and Executable on windows.

In the FAST.Farm primary input .fstf file, I found the column of SUPER CONTROLLER only have the location of the dynamic library{ .dll [Windows] or .so [Linux] }, and it haven't a user-defined way. So can I think that there hanen't a interface to other softwarea like Matlab ? And do you have some material that using FLORIS to develop the super controller?


Best regards,

Jiaping.Cui

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Wed Oct 21, 2020 6:36 am

Dear Jiaping,

The primary FAST.Farm input (*.fstf) file has not changed since the version of the precompiled Windows executable and the newer version on github, other than the addition of the Mod_AmbWind = 3 option. The Mod_AmbWind = 3 option does not change the formatting of the file (it does not add or remove lines), but it does allow the 3rd option of Mod_AmbWind, which changes some of the line comments. NREL does not intend to release other pre-compiled versions of the FAST.Farm Windows executable until the official release of FAST.Farm.

The super controller implementation being finalized now only supports a super controller, together with individual controllers, defined in dynamic library format (that is, the DISCON.dll or DISCON.so for the individual turbine controllers). This was done so as to ensure that the super controller implementation in FAST.Farm is consistent with the super controller interface available in the C++ API for interfacing OpenFAST with CFD (e.g., SOWFA). NREL does not currently have funding to develop a Simulink interface for the super controller.

FLORIS is a steady state tool, and so, can be used to derive optimal mean nacelle-yaw angles (to optimize power capture via wake steering) for a given steady wind condition. But FLORIS has no dynamics, and so, cannot be used to develop dynamic (time-varying) implementations of controllers. More information is available in the many FLORIS publications.

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

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Thu Oct 22, 2020 8:09 am

Dear Deza,

The Wind Energy journal publication I referred to above has now been posted online--see: https://onlinelibrary.wiley.com/doi/10.1002/we.2581.

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

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Jiaping.Cui
Posts: 18
Joined: Tue Aug 25, 2020 1:16 am
Organization: Shenyang University of Technology
Location: China

Re: FAST.Farm

Postby Jiaping.Cui » Mon Oct 26, 2020 1:00 am

Dear Jason,

When running FAST.Farm, I always suffer the errors as followings:

1. The model is 5MW wind turbine using Semi-submersible configuration

(1) NX_High = 300 the input parameters as following:
--- AMBIENT WIND: INFLOWWIND MODULE --- [used only for Mod_AmbWind=2]
4.0 DT Time step for low -resolution wind data interpolation; will be used as the global FAST.Farm time step (s) [>0.0]
1.0 DT_High Time step for high-resolution wind data interpolation (s) [>0.0]
913 NX_Low Number of low -resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
101 NY_Low Number of low -resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
35 NZ_Low Number of low -resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
-77.7 X0_Low Origin of low -resolution spatial nodes in X direction for wind data interpolation (m)
-500.0 Y0_Low Origin of low -resolution spatial nodes in Y direction for wind data interpolation (m)
5.0 Z0_Low Origin of low -resolution spatial nodes in Z direction for wind data interpolation (m)
9.71 dX_Low Spacing of low -resolution spatial nodes in X direction for wind data interpolation (m) [>0.0]
10.0 dY_Low Spacing of low -resolution spatial nodes in Y direction for wind data interpolation (m) [>0.0]
10.0 dZ_Low Spacing of low -resolution spatial nodes in Z direction for wind data interpolation (m) [>0.0]
300 NX_High Number of high-resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
150 NY_High Number of high-resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
120 NZ_High Number of high-resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
"InflowWind.dat" InflowFile Name of file containing InflowWind module input parameters (quoted string)
--- WIND TURBINES ---
3 NumTurbines Number of wind turbines (-) [>=1] [last 6 columns used only for Mod_AmbWind=2]
WT_X WT_Y WT_Z WT_FASTInFile X0_High Y0_High Z0_High dX_High dY_High dZ_High
(m) (m) (m) (string) (m) (m) (m) (m) (m) (m)
5.0 0.0 0.0 "5MW_OC4Semi_WSt_WavesWN_WT1.fst" -77.7 -100.0 5.0 2.0 2.0 2.0
2013.0 0.0 0.0 "5MW_OC4Semi_WSt_WavesWN_WT2.fst" 1932.37 -100.0 5.0 2.0 2.0 2.0
4021.0 0.0 0.0 "5MW_OC4Semi_WSt_WavesWN_WT3.fst" 3942.44 -100.0 5.0 2.0 2.0 2.0
--- WAKE DYNAMICS ---
3.0 dr Radial increment of radial finite-difference grid (m) [>0.0]
66 NumRadii Number of radii in the radial finite-difference grid (-) [>=2]
134 NumPlanes Number of wake planes (-) [>=2]


and the errors are:
T1:FARM_UpdateStates:FWrap_Increment:FAST_Solution:FAST_AdvanceStates:SolveOption2c_Inp2AD_SrvD:In
flowWind_CalcOutput:CalcOutput:IfW_4Dext_CalcOutput [position=(515.32, 37.154, 124.56) in
wind-file coordinates]:Interp4D:Outside the grid bounds.

Aborting FAST.Farm.


(2) NX_High = 800 the input parameters as following:
--- AMBIENT WIND: INFLOWWIND MODULE --- [used only for Mod_AmbWind=2]
4.0 DT Time step for low -resolution wind data interpolation; will be used as the global FAST.Farm time step (s) [>0.0]
1.0 DT_High Time step for high-resolution wind data interpolation (s) [>0.0]
913 NX_Low Number of low -resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
101 NY_Low Number of low -resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
35 NZ_Low Number of low -resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
-77.7 X0_Low Origin of low -resolution spatial nodes in X direction for wind data interpolation (m)
-500.0 Y0_Low Origin of low -resolution spatial nodes in Y direction for wind data interpolation (m)
5.0 Z0_Low Origin of low -resolution spatial nodes in Z direction for wind data interpolation (m)
9.71 dX_Low Spacing of low -resolution spatial nodes in X direction for wind data interpolation (m) [>0.0]
10.0 dY_Low Spacing of low -resolution spatial nodes in Y direction for wind data interpolation (m) [>0.0]
10.0 dZ_Low Spacing of low -resolution spatial nodes in Z direction for wind data interpolation (m) [>0.0]
800 NX_High Number of high-resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
150 NY_High Number of high-resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
120 NZ_High Number of high-resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
"InflowWind.dat" InflowFile Name of file containing InflowWind module input parameters (quoted string)
--- WIND TURBINES ---
3 NumTurbines Number of wind turbines (-) [>=1] [last 6 columns used only for Mod_AmbWind=2]
WT_X WT_Y WT_Z WT_FASTInFile X0_High Y0_High Z0_High dX_High dY_High dZ_High
(m) (m) (m) (string) (m) (m) (m) (m) (m) (m)
5.0 0.0 0.0 "5MW_OC4Semi_WSt_WavesWN_WT1.fst" -77.7 -100.0 5.0 2.0 2.0 2.0
2013.0 0.0 0.0 "5MW_OC4Semi_WSt_WavesWN_WT2.fst" 1932.37 -100.0 5.0 2.0 2.0 2.0
4021.0 0.0 0.0 "5MW_OC4Semi_WSt_WavesWN_WT3.fst" 3942.44 -100.0 5.0 2.0 2.0 2.0
--- WAKE DYNAMICS ---
3.0 dr Radial increment of radial finite-difference grid (m) [>0.0]
66 NumRadii Number of radii in the radial finite-difference grid (-) [>=2]
134 NumPlanes Number of wake planes (-) [>=2]


and the errors are:
T1:FARM_UpdateStates:FWrap_Increment:FAST_Solution:FAST_AdvanceStates:SolveOption2c_Inp2AD_SrvD:In
flowWind_CalcOutput:CalcOutput:IfW_4Dext_CalcOutput [position=(1046.7, -102.02, 92.504) in
wind-file coordinates]:Interp4D:Outside the grid bounds.

Aborting FAST.Farm.


I think that every turbine doesn't leave the specified high-resolution domain and has sufficient space. But the program always abort before getting the finaling time. So the first answer I want to know is which lead to this error?


2.The model is IEA-15-240-RWT-Monopile configuration
the input parameters as following:

--- AMBIENT WIND: INFLOWWIND MODULE --- [used only for Mod_AmbWind=2]
4.0 DT Time step for low -resolution wind data interpolation; will be used as the global FAST.Farm time step (s) [>0.0]
1.0 DT_High Time step for high-resolution wind data interpolation (s) [>0.0]
913 NX_Low Number of low -resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
161 NY_Low Number of low -resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
45 NZ_Low Number of low -resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
-80.0 X0_Low Origin of low -resolution spatial nodes in X direction for wind data interpolation (m)
-800.0 Y0_Low Origin of low -resolution spatial nodes in Y direction for wind data interpolation (m)
5.0 Z0_Low Origin of low -resolution spatial nodes in Z direction for wind data interpolation (m)
9.71 dX_Low Spacing of low -resolution spatial nodes in X direction for wind data interpolation (m) [>0.0]
10.0 dY_Low Spacing of low -resolution spatial nodes in Y direction for wind data interpolation (m) [>0.0]
10.0 dZ_Low Spacing of low -resolution spatial nodes in Z direction for wind data interpolation (m) [>0.0]
460 NX_High Number of high-resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
240 NY_High Number of high-resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
240 NZ_High Number of high-resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
"InflowWind.dat" InflowFile Name of file containing InflowWind module input parameters (quoted string)
--- WIND TURBINES ---
3 NumTurbines Number of wind turbines (-) [>=1] [last 6 columns used only for Mod_AmbWind=2]
WT_X WT_Y WT_Z WT_FASTInFile X0_High Y0_High Z0_High dX_High dY_High dZ_High
(m) (m) (m) (string) (m) (m) (m) (m) (m) (m)
100.0 0.0 0.0 "IEA-15-240-RWT-Monopile_WT1.fst" -80.0 -240.0 5.0 2.0 2.0 2.0
2100.0 0.0 0.0 "IEA-15-240-RWT-Monopile_WT2.fst" 1932.37 -240.0 5.0 2.0 2.0 2.0
4110.0 0.0 0.0 "IEA-15-240-RWT-Monopile_WT3.fst" 3942.44 -240.0 5.0 2.0 2.0 2.0
--- WAKE DYNAMICS ---
3.0 dr Radial increment of radial finite-difference grid (m) [>0.0]
142 NumRadii Number of radii in the radial finite-difference grid (-) [>=2]
24 NumPlanes Number of wake planes (-) [>=2]


and the errors are:
Farm_Initialize:Farm_ValidateInput:OutFmt produces a column width of 10 instead of 14 characters.
Farm_Initialize:T1:Farm_InitFAST:FWrap_Init:FAST_InitializeAll:MAP_Init:Cannot read the MAP input
file.

Aborting FAST.Farm.


I try to debug many parameters such as dr、NumRadii、NumPlanes、NX_High and so on. So the second questuion is what I should do to solve this fault or which paratemer I should debug ?

Best regards in advance,

Jiaping.Cui

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Mon Oct 26, 2020 7:30 am

Dear Jiaping,

Regarding 1.1, the position (515.32, 37.154, 124.56) is in the coordinate system of wind turbine #1, whose origin is at (5,0,0) in the FAST.Farm global coordinates. So, the global coordinates of this position are (520.32, 37.154, 124.56). However, the high-resolution box only extends to (NX_High-1)*dX_High - X0_High = (300-1)*2-77.7 = 520.3 m downwind in global coordinates. So, the global X-position is out of bounds of the high-resolution domain.

Regarding 1.2, the position (1046.7, -102.02, 92.504) for wind turbine #1 is out of of bounds of the high-resolution domain in the global Y position because -102.02 < Y0_High = -100.

Regarding 2, it appears that the name of, or path to, the MAP++ input file is not specified correctly in the OpenFAST input file for wind turbine #1.

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

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Jiaping.Cui
Posts: 18
Joined: Tue Aug 25, 2020 1:16 am
Organization: Shenyang University of Technology
Location: China

Re: FAST.Farm

Postby Jiaping.Cui » Mon Oct 26, 2020 8:45 am

Dear Jason,

When I modify the wind speed or the distance between two wind turbines, the program often jump a warning that

" Warning: Turning off Unsteady Aerodynamics due to high angle of attack (-68.13 deg). BladeNode = 16, Blade = 3 "
.....
.....
then the program will abort after a few moments.

How can I avoid this warning and aborting ?

Best regards in advance,

Jiaping.Cui

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Mon Oct 26, 2020 9:44 am

Dear Jiaping,

You haven't provided enough information for me to understand the cause of the large angle of attack warning. A few clarifying questions:
  • How soon into the simulation does this warning appear?
  • How is the turbine responding at the time of the warning? Are the rotor speed, pitch, and turbine deflections reasonable for the wind speed simulated?
  • What error is reported that is causing the simulation to abort?
Best regards,
Jason Jonkman, Ph.D.
Senior Engineer | National Wind Technology Center (NWTC)

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Jiaping.Cui
Posts: 18
Joined: Tue Aug 25, 2020 1:16 am
Organization: Shenyang University of Technology
Location: China

Re: FAST.Farm

Postby Jiaping.Cui » Tue Oct 27, 2020 2:00 am

Dear Jason,

I have put the " inflowWind.dat、program.txt (the message in the command)、Tsinflow.fstf " into https://drive.google.com/drive/folders/1BY1zV7F3a7ITgnFII7OxdpcQ8_-rFfsv

I think the warnnings and errors in the command is due to I modified the dr、Numradii、NumPlanes, but I can't define, hoping you can give me some suggestions about these three parameters.

Thank you for taking your precious time to read these documents.

And I have an additional question.

1.How far between two neighboring wake planes is ? I can't find in the user's guide.

That's all.

Best regards in advance,

Jiaping.Cui

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Tue Oct 27, 2020 6:53 am

Dear Jiaping,

I don't have access to your Google drive folder; I've submitted a request for access.

Two wake planes are separated by the wake propagation speed (which would be the spatially averaged mean wind speed minus a contribution from the wake deficit) times the low-resolution domain time step, DT_Low.

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

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Jiaping.Cui
Posts: 18
Joined: Tue Aug 25, 2020 1:16 am
Organization: Shenyang University of Technology
Location: China

Re: FAST.Farm

Postby Jiaping.Cui » Tue Oct 27, 2020 8:26 am

Dear Jason,

I'm so sorry and I had modified access, and now the website is https://drive.google.com/drive/folders/1BY1zV7F3a7ITgnFII7OxdpcQ8_-rFfsv, and you may need to download these three files.

Best regards,

Jiaping.Cui

Jason.Jonkman
Posts: 5300
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Wed Oct 28, 2020 2:30 pm

Dear Jiaping.Cui,

Just a couple comments:
  • The high angle of attack warnings are soon followed by a large blade deflection warning and tower strike. This suggests to me that the model has gone numerically unstable. Have you changed the OpenFAST models in any way, e.g. mass, stiffness, geometry, or time step? Are the initial conditions of rotor speed and blade pitch angle set appropriately for the 14 m/s inflow you are simulating (RotSpeed = 12.1 rpm, BlPitch = 3.823 deg)? It appears that you are using the DISCON DLL; are you using distinct DLLs for each wind turbine? (If not, the controller calculations would be corrupted.) This requires the need for distinct ServoDyn primary input files, referencing the appropriate DLL name, and distinct OpenFAST primary input files, each referencing the appropriate ServoDyn primary input file name.
  • I'm a bit surprised you are getting warnings about the center of a wake plane passing the lowest-most Z boundary of the low-resolution domain very soon into the simulation. Perhaps looking at the VTK visualization of the wake will help understand what is going on. That said, if the OpenFAST models are going numerically unstable, this could have a large impact on the wake response. So, I'm hopeful that when you solve the OpenFAST instability, these wake warnings will disappear.
Best regards,
Jason Jonkman, Ph.D.
Senior Engineer | National Wind Technology Center (NWTC)

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Jiaping.Cui
Posts: 18
Joined: Tue Aug 25, 2020 1:16 am
Organization: Shenyang University of Technology
Location: China

Re: FAST.Farm

Postby Jiaping.Cui » Sun Nov 01, 2020 5:25 am

Dear Jason,

Thank you very much for your comments, I used the distinct DLLs for each wind turbine and all the problems were solved about the NREL-5MW wind turbine.

And I found a point puzzling me for a long time. Before I run the floating 5MW case successfully, the position of turbine always pass the high-High resolution. So I always extend the X-axis distance for the longer simulation time. By chance,I open the .VTK files and found the floating wind turbine drifted away, so I felt the reason may be the moor flag is false, and then I change the flag, the program runned normally finnally. Though this is a small point for others maybe, but when I found this problem and solved it successfully by myself, I am very excited. So I want to say thank again to you Sincerely.

When I use the same method by IEA-15MW, it occured different trouble, I put four files into https://drive.google.com/drive/folders/1oJRXXi57rKSLUqMgEIZ7xlziBE4JThgD ,they are the InflowWind、the program(the message in command)、the input file.fstf and the wind turbine input file.fst. Excuse you and hoping to get your suggestions about the warnings and aborting again.


Best regards,

Jiaping.Cui


Return to “General”

Who is online

Users browsing this forum: No registered users and 1 guest