FAST.Farm

Topics of general, but wind-related interest.

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Ruiliang.Wang
Posts: 87
Joined: Sun Nov 24, 2013 6:21 pm
Organization: YANSHAN UNIVERSITY
Location: China

Re: FAST.Farm

Postby Ruiliang.Wang » Wed Mar 31, 2021 5:08 am

Dear Jason,

Thank you for your reply kindly. I have solved the problems.
I have two suggetstion for the fast.farm visualization.
Firstly,I found the VTK file was save the in the folder 'vtk_ff',I hope the user can define the file name and dir byself.
Secondly. I found the issue that the XY and YZ plane created by fast.farm was saved in the vtk_ff folder. but when i set XZ plane, the XZ VTK data was saved in the outside of vtk_ff folder. I do not sure if it is a bug.

Yours Sincerely.

Ruiliang.Wang

Ruiliang.Wang
Posts: 87
Joined: Sun Nov 24, 2013 6:21 pm
Organization: YANSHAN UNIVERSITY
Location: China

Re: FAST.Farm

Postby Ruiliang.Wang » Wed Mar 31, 2021 5:41 am

Dear Jason,
I run the demo in the fast.farm. I'm confused about vtk animation like below [img]
fastfarm.png
[/img];
I mark the black block in the image. It show the it is not continuous between the low and high resolution as show. Is it correct?

Yours Sincerely

Ruiliang.Wang
Attachments
fastfarm.png
fastfarm.png (43.41 KiB) Viewed 481 times

Jason.Jonkman
Posts: 5776
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Re: FAST.Farm

Postby Jason.Jonkman » Wed Mar 31, 2021 6:46 am

Dear Ruiliang,

OK, I've added your request for specifying the name of the vtk_ff directory to our to-do list.

I found and fixed the small bug causing the directory where the XZ VTK data is stored to be incorrect, and pushed this fix to the active FAST.Farm pull request. Pulling and recompiling FAST.Farm should solve the problem.

I don't believe the image you are showing includes both the low- and high-resolution domains; I believe just the low-resolution domain is shown. I suspect this visualization is early enough in the simulation such that the wakes have not yet reached the downstream wind turbines. Alternatively, the number of wake planes (NumPlanes) is set too low such that the wake is not propagating downstream far enough to reach the downstream wind turbines.

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

Ruiliang.Wang
Posts: 87
Joined: Sun Nov 24, 2013 6:21 pm
Organization: YANSHAN UNIVERSITY
Location: China

Re: FAST.Farm

Postby Ruiliang.Wang » Thu Apr 01, 2021 12:51 am

Dear jason,

I have found the reason,As you said the reason is the NumPlanes is too low. I do not know how the variables affect the result and how reasonable this value is.
I want to know what's the meaning of the variables (dr,NumRadii,NumPlanes) .Do you provide the user manual papar ?

Best Regards

Ruiliang

Jason.Jonkman
Posts: 5776
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Thu Apr 01, 2021 6:29 am

Dear Ruiliang,

The FAST.Farm User's Guide and Theory Manuel will be published very soon. I figured you had it already, but I'll forward the nearly finalized version to you via e-mail.

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

Younes.Oudich
Posts: 33
Joined: Fri Oct 02, 2020 2:44 am
Organization: self
Location: Belgium

Re: FAST.Farm

Postby Younes.Oudich » Wed Apr 07, 2021 2:26 am

Dear Jason,

I try to implement a simple yaw controller using the SC module in FAST.Farm. I implement the connexion between the two dll files (sc_dll for FAST.Farm and DISCON_SC for the wind turbine OpenFAST) using from_SC or to_SC arrays, as shown in the figure below. In the sc_dll file, I put the commands in SC_CalcOutputs subroutine. When I run FAST.Farm with these controllers, I have the following error:

Code: Select all

**************************************************************************************************
FAST.Farm
 
Copyright (C) 2017 National Renewable Energy Laboratory
 
This program is licensed under Apache License Version 2.0 and comes with ABSOLUTELY NO WARRANTY.
See the "LICENSE" file distributed with this software for details.
**************************************************************************************************
 
FAST.Farm-v1.0.0-144-g254fc1a0-dirty
Compile Info:
 - Architecture: 64 bit
 - Precision: single
Execution Info:
 - Date: 04/07/2021
 - Time: 10:14:17+0200
 
 Heading of the FAST.Farm input file:
   Sample FAST.Farm input file
Running AWAE.
Running InflowWind.
Running WakeDynamics.
Running FASTWrapper.
Running OpenFAST.
OpenFAST input file heading:
    FAST Certification Test #26: NREL 5.0 MW Baseline Wind Turbine (Onshore)
 
Running ElastoDyn.
Running AeroDyn.
Running AirfoilInfo.
Running BEM.
Running InflowWind.
Running ServoDyn.
Running ServoDyn Interface for Bladed Controllers.
 Timestep: 0 of 200 seconds.
forrtl: severe (157): Program Exception - access violation
Image              PC                Routine            Line        Source             
DISCON_SC.dll      00007FFDB8101DA6  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF6216C5566  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF6216C43AD  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF6217F1D88  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF62165EA41  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF62165C108  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF620E2CB86  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF623C43E2A  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF623A78EE0  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF6234A47CE  Unknown               Unknown  Unknown
FAST.Farm_x64.exe  00007FF623CFFCC9  Unknown               Unknown  Unknown
KERNEL32.DLL       00007FFDFD147034  Unknown               Unknown  Unknown
ntdll.dll          00007FFDFE722651  Unknown               Unknown  Unknown


SC issue.png
SC issue.png (326.14 KiB) Viewed 433 times


Do you have any suggestions to overcome this issue please?

Kindest regards
Younes

Jason.Jonkman
Posts: 5776
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
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Re: FAST.Farm

Postby Jason.Jonkman » Wed Apr 07, 2021 6:26 am

Dear Younes,

The error means that the DISCON_SC.dll is accessing memory it shouldn't be. In the supercontroller interface, from_SC() is an array of size NumSC2Ctrl*nTurbines and to_SC() is allocated to a array of size NumCtrl2SC*nTurbines, but the DISCON_SC.dll of each wind turbine can only access values for the given turbine (with arrays of size NumSC2Ctrl and NumCtrl2SC). What have you set NumSC2Ctrl and NumCtrl2SC to in sc_init() and how many wind turbines are you simulating in FAST.Farm?

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

Younes.Oudich
Posts: 33
Joined: Fri Oct 02, 2020 2:44 am
Organization: self
Location: Belgium

Re: FAST.Farm

Postby Younes.Oudich » Wed Apr 07, 2021 10:31 am

Dear Jason,

Thank you for the clarification. I use to_sc array up to 2 elements, and from_SC up to 4 elements. Therefore, I set the following parameters in SC_Init as :

Code: Select all

   nInpGlobal        = 0
   NumCtrl2SC        = 4
   NumParamGlobal    = 0
   NumParamTurbine   = 4
   NumStatesGlobal   = 0
   NumStatesTurbine  = 0
   NumSC2CtrlGlob    = 0
   NumSC2Ctrl        = 4


In SC_CalcOutputs, knowing that I am working on only a single wind turbine (nTurbines is 1 I guess in this case), I set :

Code: Select all

   do j = 1, nTurbines
       from_SC(2)=0.0 !time activate the yaw controller
       IF (t<=100) THEN
            from_SC(3)=0.17!yaw angle command
       ELSE
            from_SC(3)=0.35!yaw angle command
       ENDIF
       from_SC(4)=to_SC(2)
       
   end do


And that's all for the sc_dll file.

For the DISCON_SC file, these are the changes (for my yaw controller) that I added :

Code: Select all

!===============My Yaw controller=================

    Yaw_angle=avrSWAP(37) !yaw angle input (rad)

    Tactivate=from_SC(2) !Tactivate time to start the controller   
    Yaw_angle_com=from_SC(3) !Yaw angle commande
 
    IF (Time>=Tactivate) THEN

        ind=from_SC(4) !initialize to 0 in t=0 from_sc
        YawError=Yaw_angle_com - Yaw_angle     

        IF ( (YawError >0.0) .OR. (ind==1)) THEN
            ind=1
            YawRate=0.005235 !0.3 deg/s
            IF (YawError<=0.0) THEN
                ind=0
                YawRate=0.0
            ENDIF
            avrSWAP(48) = YawRate
            to_SC(2)=ind
        ELSE IF ( (YawError <0.0) .OR. (ind==2)) THEN
            ind=2
            YawRate=-0.005235 !-0.3 deg/s
            IF (YawError>=0.0) THEN
                ind=0
                YawRate=0.0
            ENDIF
            avrSWAP(48) = YawRate
            to_SC(2)=ind
        ELSE
            ind=0
            YawRate=0.0
            avrSWAP(48) = YawRate
            to_SC(2)=ind
        ENDIF   
    ENDIF
   
!=======================================================================


It is still not working even after setting NumSC2Ctrl and NumCtrl2SC to 4. I might have missed something but I can't figure out the issue :(

Jason.Jonkman
Posts: 5776
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Wed Apr 07, 2021 11:06 am

Dear Younes,

The error is not obvious to me from my quick skim (and I'm not following all of your control logic, particularly "ind", but haven't spent much time to understand). I suggest compiling in debug mode and stepping through the solution with the debugger.

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

Younes.Oudich
Posts: 33
Joined: Fri Oct 02, 2020 2:44 am
Organization: self
Location: Belgium

Re: FAST.Farm

Postby Younes.Oudich » Thu Apr 08, 2021 5:38 am

Dear Jason,

I was using the old version of FAST.Farm that I think it wasn't able to handle the SC yet. I just built FAST.Farm by taking the last version on the website that uses OpenFAST and the SC worked as expected. Thank you so much for the help!
I still have a problem though when I try to yaw the turbine from 0° to 20°. When no yawing is set, everything works well. But when I start yawing the turbine, I get the following error related to boundary conditions:

Code: Select all


T1:FARM_UpdateStates:FWrap_Increment:FAST_Solution:FAST_AdvanceStates:SolveOption2c_Inp2AD_SrvD:In
flowWind_CalcOutput:CalcOutput:IfW_4Dext_CalcOutput [position=(14.024, -56.848, 113.92) in
wind-file coordinates]:Interp4D:Outside the grid bounds.
 

 
 Aborting FAST.Farm.
 


I don't know why I have this issue since my grid size is: 2000x1000x160 m^3, and the point (14.024, -56.848, 113.92) is inside the grid.
This is my Ambient wind and turbine position parameters in the FSTF file.

Code: Select all

--- AMBIENT WIND: INFLOWWIND MODULE --- [used only for Mod_AmbWind=2]
2.0                DT                 Time step for low -resolution wind data interpolation; will be used as the global FAST.Farm time step (s) [>0.0]
0.1                DT_High            Time step for high-resolution wind data interpolation (s) [>0.0]
201               NX_Low             N130umber  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]
17                 NZ_Low             Number  of low -resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
0.0                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)
10.0               Z0_Low             Origin  of low -resolution spatial nodes in Z direction for wind data interpolation (m)
10.0               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]
10                 NX_High            Number  of high-resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
22                 NY_High            Number  of high-resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
17                 NZ_High            Number  of high-resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
"WakeEffect_inflow_nFF.dat"   InflowFile         Name of file containing InflowWind module input parameters (quoted string)
--- WIND TURBINES ---
1                  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)
126.0  0.0  0.0    "WakeEffect_WT1_nFF.fst"            50.0    -100.0   10.0      10.0     10.0     10.0


I even looked at the wind flow conditions in Paraview and I couldn't notice the issue. Do you have any ideas ?
Paraview.PNG
Paraview.PNG (138.68 KiB) Viewed 408 times


Sorry for the inconvenience

Kindest regards

Younes

Jason.Jonkman
Posts: 5776
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Thu Apr 08, 2021 6:53 am

Dear Younes,

You are plotting the low-resolution domain, but the problem is with the high-resolution domain. From your input file specification, the high-resolution domain extends from 50 to 140 m in the global FAST.Farm coordinate system, which is -76 to 14 m in the local wind turbine coordinate system. When you yaw the turbine, my guess is the aerodynamic nodes at the blade tip leave the downwind side of the high-resolution domain. Changing NX_High or X0_High will likely solve the problem.

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

Younes.Oudich
Posts: 33
Joined: Fri Oct 02, 2020 2:44 am
Organization: self
Location: Belgium

Re: FAST.Farm

Postby Younes.Oudich » Thu Apr 08, 2021 11:22 am

Dear Jason,

That makes sense and it worked. Thank you so much!

Kindest regards

Younes

Younes.Oudich
Posts: 33
Joined: Fri Oct 02, 2020 2:44 am
Organization: self
Location: Belgium

Re: FAST.Farm

Postby Younes.Oudich » Wed Apr 14, 2021 6:07 am

Dear Jason,

I try to see the effect of the wake (near and far wake) of one turbine on another one in FAST.Farm. I put the second turbine at a distance 410.6m downstream the first one. At a certain time, I get the following error:

Code: Select all

 Time: 268 of 1500 seconds.  Estimated final completion at 14:21:57.
 
T2:FARM_UpdateStates:NearWakeCorrection:Wake model is not valid in the propeller-brake region,
i.e., Ct > 2.0.


 
 Aborting FAST.Farm.


Do you have any suggestions? Here is my input FSTF file:

Code: Select all

FAST.Farm v1.00.* INPUT FILE
Sample FAST.Farm input file
--- SIMULATION CONTROL ---
TRUE              Echo               Echo input data to <RootName>.ech? (flag)
FATAL              AbortLevel         Error level when simulation should abort (string) {"WARNING", "SEVERE", "FATAL"}
1500.0             TMax               Total run time (s) [>=0.0]
True              UseSC              Use a super controller? (flag)
2                  Mod_AmbWind        Ambient wind model (-) (switch) {1: high-fidelity precursor in VTK format, 2: InflowWind module}
--- SUPER CONTROLLER --- [used only for UseSC=True]
"sc_dll.dll"       SC_FileName        Name/location of the dynamic library {.dll [Windows] or .so [Linux]} containing the Super Controller algorithms (quoated string)
--- AMBIENT WIND ---
2.0                DT                 Time step for low -resolution wind data input files; will be used as the global FAST.Farm time step (s) [>0.0]
0.1          DT_High            Time step for high-resolution wind data input files (s) [>0.0]
"Unused"          WindFilePath       Path name to wind data files from precursor (string)
False              ChkWndFiles        Check all the ambient wind files for data consistency? (flag)
--- AMBIENT WIND: INFLOWWIND MODULE --- [used only for Mod_AmbWind=2]
2.0                DT                 Time step for low -resolution wind data interpolation; will be used as the global FAST.Farm time step (s) [>0.0]
0.1                DT_High            Time step for high-resolution wind data interpolation (s) [>0.0]
301               NX_Low             N130umber  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]
17                 NZ_Low             Number  of low -resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
0.0                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)
10.0               Z0_Low             Origin  of low -resolution spatial nodes in Z direction for wind data interpolation (m)
10.0               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]
41                 NX_High            Number  of high-resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
41                 NY_High            Number  of high-resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
17                 NZ_High            Number  of high-resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
"WakeEffect_inflow_nFF.dat"   InflowFile         Name of file containing InflowWind module input parameters (quoted string)
--- WIND TURBINES ---
2                  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)
126.0  0.0  0.0    "WakeEffect_WT1_nFF.fst"            0.0    -150.0   10.0      10.0     10.0     10.0
536.6  0.0  0.0    "WakeEffect_WT1_nFF.fst"            500.0    -150.0   10.0      10.0     10.0     10.0
--- WAKE DYNAMICS ---
2.0                dr                 Radial increment of radial finite-difference grid (m) [>0.0]
110                 NumRadii           Number of radii in the radial finite-difference grid (-) [>=2]
73                N63umPlanes          N130umber of wake planes (-) [>=2]
DEFAULT            f_c                Cut-off (corner) frequency of the low-pass time-filter for the wake advection, deflection, and meandering model (Hz) [>0.0] or DEFAULT [DEFAULT=0.0007]
DEFAULT            C_HWkDfl_O         Calibrated parameter in the correction for wake deflection defining the horizontal offset at the rotor                                               (m    ) or DEFAULT [DEFAULT= 0.0  ]
DEFAULT            C_HWkDfl_OY        Calibrated parameter in the correction for wake deflection defining the horizontal offset at the rotor scaled with                         yaw error (m/deg) or DEFAULT [DEFAULT= 0.3  ]
DEFAULT            C_HWkDfl_x         Calibrated parameter in the correction for wake deflection defining the horizontal offset              scaled with downstream distance               (-    ) or DEFAULT [DEFAULT= 0.0  ]
DEFAULT            C_HWkDfl_xY        Calibrated parameter in the correction for wake deflection defining the horizontal offset              scaled with downstream distance and yaw error (1/deg) or DEFAULT [DEFAULT=-0.004]
DEFAULT            C_NearWake         Calibrated parameter for the near-wake correction (-) [>1.0] or DEFAULT [DEFAULT=1.8]
DEFAULT            k_vAmb             Calibrated parameter for the influence of ambient turbulence in the eddy viscosity (-) [>=0.0] or DEFAULT [DEFAULT=0.05 ]
DEFAULT            k_vShr             Calibrated parameter for the influence of the shear layer    in the eddy viscosity (-) [>=0.0] or DEFAULT [DEFAULT=0.016]
DEFAULT            C_vAmb_DMin        Calibrated parameter in the eddy viscosity filter function for ambient turbulence defining the transitional diameter fraction between the minimum and exponential regions (-) [>=0.0          ] or DEFAULT [DEFAULT= 0.0 ]
DEFAULT            C_vAmb_DMax        Calibrated parameter in the eddy viscosity filter function for ambient turbulence defining the transitional diameter fraction between the exponential and maximum regions (-) [> C_vAmb_DMin  ] or DEFAULT [DEFAULT= 1.0 ]
DEFAULT            C_vAmb_FMin        Calibrated parameter in the eddy viscosity filter function for ambient turbulence defining the value in the minimum region                                                (-) [>=0.0 and <=1.0] or DEFAULT [DEFAULT= 1.0 ]
DEFAULT            C_vAmb_Exp         Calibrated parameter in the eddy viscosity filter function for ambient turbulence defining the exponent in the exponential region                                         (-) [> 0.0          ] or DEFAULT [DEFAULT= 0.01]
DEFAULT            C_vShr_DMin        Calibrated parameter in the eddy viscosity filter function for the shear layer    defining the transitional diameter fraction between the minimum and exponential regions (-) [>=0.0          ] or DEFAULT [DEFAULT= 3.0 ]
DEFAULT            C_vShr_DMax        Calibrated parameter in the eddy viscosity filter function for the shear layer    defining the transitional diameter fraction between the exponential and maximum regions (-) [> C_vShr_DMin  ] or DEFAULT [DEFAULT=25.0 ]
DEFAULT            C_vShr_FMin        Calibrated parameter in the eddy viscosity filter function for the shear layer    defining the value in the minimum region                                                (-) [>=0.0 and <=1.0] or DEFAULT [DEFAULT= 0.2 ]
DEFAULT            C_vShr_Exp         Calibrated parameter in the eddy viscosity filter function for the shear layer    defining the exponent in the exponential region                                         (-) [> 0.0          ] or DEFAULT [DEFAULT= 0.1 ]
DEFAULT            Mod_WakeDiam       Wake diameter calculation model (-) (switch) {1: rotor diameter, 2: velocity based, 3: mass-flux based, 4: momentum-flux based} or DEFAULT [DEFAULT=1]
DEFAULT            C_WakeDiam         Calibrated parameter for wake diameter calculation (-) [>0.0 and <0.99] or DEFAULT [DEFAULT=0.95] [unused for Mod_WakeDiam=1]
DEFAULT            Mod_Meander        Spatial filter model for wake meandering (-) (switch) {1: uniform, 2: truncated jinc, 3: windowed jinc} or DEFAULT [DEFAULT=3]
DEFAULT            C_Meander          Calibrated parameter for wake meandering (-) [>=1.0] or DEFAULT [DEFAULT=1.9]
--- VISUALIZATION ---
False              WrDisWind          Write low- and high-resolution disturbed wind data to <RootName>.Low.Dis.t<n>.vtk etc.? (flag)
1                  NOutDisWindXY      Number of XY planes for output of disturbed wind data across the low-resolution domain to <RootName>.Low.DisXY<n_out>.t<n>.vtk (-) [0 to 9]
90.0               OutDisWindZ        Z coordinates of XY planes for output of disturbed wind data across the low-resolution domain (m) [1 to NOutDisWindXY] [unused for NOutDisWindXY=0]
0                  NOutDisWindYZ      Number of YZ planes for output of disturbed wind data across the low-resolution domain to <RootName>/Low.DisYZ<n_out>.t<n>.vtk (-) [0 to 9]
748.0, 1252.0, 1378.0, 1504.0, 1630.0, 1756.0, 1882.0, 2008.0   OutDisWindX        X coordinates of YZ planes for output of disturbed wind data across the low-resolution domain (m) [1 to NOutDisWindYZ] [unused for NOutDisWindYZ=0]
0                  NOutDisWindXZ      Number of XZ planes for output of disturbed wind data across the low-resolution domain to <RootName>/Low.DisXZ<n_out>.t<n>.vtk (-) [0 to 9]
0.0             OutDisWindY        Y coordinates of XZ planes for output of disturbed wind data across the low-resolution domain (m) [1 to NOutDisWindXZ] [unused for NOutDisWindXZ=0]
10.0                WrDisDT            Time step for disturbed wind visualization output (s) [>0.0] or DEFAULT [DEFAULT=DT] [unused for WrDisWind=False and NOutDisWindXY=NOutDisWindYZ=NOutDisWindXZ=0]
--- OUTPUT ---
True               SumPrint           Print summary data to <RootName>.sum? (flag)
99999.9            ChkptTime          Amount of time between creating checkpoint files for potential restart (s) [>0.0]
0.0              TStart             Time to begin tabular output (s) [>=0.0]
1                  OutFileFmt         Format for tabular (time-marching) output file (switch) {1: text file [<RootName>.out], 2: binary file [<RootName>.outb], 3: both}
True               TabDelim           Use tab delimiters in text tabular output file? (flag) {uses spaces if False}
"ES10.3E2"         OutFmt             Format used for text tabular output, excluding the time channel.  Resulting field should be 10 characters. (quoted string)
16                 NOutRadii          Number of radial nodes         for wake output for an individual rotor (-) [0 to 20]
0, 2, 4, 8, 9, 11, 13, 15, 17, 19, 21, 24, 28, 33, 50, 64  OutRadii           List of radial nodes         for wake output for an individual rotor (-) [1 to NOutRadii] [unused for NOutRadii=0]
7                  NOutDist           Number of downstream distances for wake output for an individual rotor (-) [0 to 9 ]
504.0, 567.0, 630.0, 693.0, 756.0, 819.0, 882.0       OutDist            List of downstream distances for wake output for an individual rotor (m) [1 to NOutDist ] [unused for NOutDist =0]
1                  NWindVel           Number of points for wind output (-) [0 to 9]
126.0             WindVelX           List of coordinates in the X direction for wind output (m) [1 to NWindVel] [unused for NWindVel=0]
0.0             WindVelY           List of coordinates in the Y direction for wind output (m) [1 to NWindVel] [unused for NWindVel=0]
90.0               WindVelZ           List of coordinates in the Z direction for wind output (m) [1 to NWindVel] [unused for NWindVel=0]
                   OutList            The next line(s) contains a list of output parameters.  See OutListParameters.xlsx for a listing of available output channels (quoted string)
"RtAxsXT1     , RtAxsYT1     , RtAxsZT1"
"RtPosXT1     , RtPosYT1     , RtPosZT1"
"YawErrT1"
"TIAmbT1"
"WkPosXT1D1   , WkPosXT1D2   , WkPosXT1D3   , WkPosXT1D4   , WkPosXT1D5   , WkPosXT1D6   , WkPosXT1D7"
"WkPosYT1D1   , WkPosYT1D2   , WkPosYT1D3   , WkPosYT1D4   , WkPosYT1D5   , WkPosYT1D6   , WkPosYT1D7"
"WkDfVxT1N01D1, WkDfVxT1N02D1, WkDfVxT1N03D1, WkDfVxT1N04D1, WkDfVxT1N05D1, WkDfVxT1N06D1, WkDfVxT1N07D1, WkDfVxT1N08D1, WkDfVxT1N09D1, WkDfVxT1N10D1, WkDfVxT1N11D1, WkDfVxT1N12D1, WkDfVxT1N13D1, WkDfVxT1N14D1, WkDfVxT1N15D1, WkDfVxT1N16D1, WkDfVxT1N17D1, WkDfVxT1N18D1, WkDfVxT1N19D1, WkDfVxT1N20D1"
END of input file (the word "END" must appear in the first 3 columns of this last OutList line)



Sorry for the inconvenience

Kindest regards

Younes

Jason.Jonkman
Posts: 5776
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: FAST.Farm

Postby Jason.Jonkman » Wed Apr 14, 2021 6:39 am

Dear Younes,

FAST.Farm will throw this error when the rotor thrust is so high that the near-wake correction model is no longer valid. I expect that the downstream turbine (T2) is not operating as expected if the thrust is this high. Is 268 s, when the error is triggered, the time when the wake from the upstream turbine (T1) hits the downstream turbine? Can you confirm that the control of T2 (speed, pitch) is expected up until the error is triggered?

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

Younes.Oudich
Posts: 33
Joined: Fri Oct 02, 2020 2:44 am
Organization: self
Location: Belgium

Re: FAST.Farm

Postby Younes.Oudich » Wed Apr 14, 2021 10:13 am

Dear Jason,

Thank you for the reply. For the Pitch and torque controllers, I use the OpenFAST dll file given that uses a look-up table for the torque control and a gain scheduled PI control for the pitch above the rated speed.
Looking at the pitch, torque, and generator speed as you suggested, the pitch is always 0° for both turbines because the wind speed used is 10m/s, which is below the 3rd region. The torque and generator speed both make sense for the upstream turbine (Turbine 1), as you can see in the green rectangle below. But for the downstream turbine (Turbine 2), I don't understand why the torque stays constant while the generator speed decreases (red square). I was expecting the generator torque to decrease as well as the generator speed, almost linearly (since we are in regions 1(1/2) and 2 for the NREL 5MW generator torque - generator speed Figure 7.2)

Generator speed and torque FF.png
Generator speed and torque FF.png (126.21 KiB) Viewed 344 times


This is the sequence of images before it throws the error: The error happens at the end, so after the wake of the first turbine hits the second one.
ezgif.com-gif-maker.gif
ezgif.com-gif-maker.gif (718.58 KiB) Viewed 344 times


Do you have any ideas where the issue may come from ?

Kindest regars

Younes


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