Dear @Andre.White,
The tower drag coefficient is specified in the “TOWER INFLUENCE AND AERODYNAMICS” section of the AeroDyn v15 primary input file. The value is specified via the TwrCd (3rd) column of the distributed aerodynamic tower data.
Best regards,
Thanks @Jason.Jonkman. Is the drag coefficient also located in AeroDynv14?
Regards,
AOAW
Dear @Andre.White,
Tower drag is only available if you use the mostly undocumented “NEWTOWER” feature of AeroDyn v14. But this model had limitations that were resolved in AeroDyn v15, so, I would recommend using AeroDyn v15 over AeroDyn v14 if you wish to enable tower aerodynamics. We are intending to deprecate support for AeroDyn v14 very soon.
Best regards
Hi @Jason.Jonkman I tried to compute natural frequencies using the IEA 10MW turbine since it uses Aerodynv15. However, I get this error in MATLAB:
Rotating channel “ED TwstDefl1, (deg)” does not form a unique blade triplet. Blade(s) not found: 2 3
I still get output file with natural frequencies and damping ratios but not sure if they are accurate based on the error above.
I used a blade length of 90 m and tower length of 115.63 m.
Regards,
AOAW
Dear @Andre.White,
This warning is associated with the write output from ElastoDyn TwstDefl1, and so, should only effect the linearized output equation (matrices C and D, not A and B). You should be able to eliminate the warning by ensuring the outputs are consistent across all blades (i.e., remove output TwstDefl1 or add outputs TwstDefl2 and TwstDefl3).
Best regards,
Noted. Thank you @Jason.Jonkman .
Regards,
AOAW
Hi @Jason.Jonkman:
I have another query about AeroDynv14. I tried to turn on the tower aerodynamic loads but I am getting this error. It seems to be searching for a file. The extract from AeroDynv14 is shown below:
True TwrPotent - Calculate tower potential flow (flag) INSTEAD OF 9999.9 ShadHWid - Tower-shadow half width (m)
True TwrShadow - Calculate tower shadow (flag) INSTEAD OF 9999.9 T_Shad_Refpt- Tower-shadow reference point (m)
“unused” TwrFile - Tower drag file name (quoted string)
True CalcTwrAero - Calculate aerodynamic drag of the tower at the ElastoDyn nodes. TwrPotent must be true.
It is searching for TwrFile. The error I got was as follows:
FAST_InitializeAll:AD14_Init:OpenFInpFile:The input file, “.\10MW_Reference WT\unused”, was not found.
Do you know how I could solve that problem. I think my fore-aft moments are underestimated because I have not turned on tower aerodynamic loads.
Regards,
AOAW
Dear @Andre.White,
If you want to use the “NEWTOWER” feature of AeroDyn v14, you must provide a TwrFile. Bug again, I recommend upgrading to AeroDyn v15 rather than enabling the “NEWTOWER” feature of AeroDyn v14.
Best regards,
Hi @Jason.Jonkman:
I am in a bit of a jam. I am using DTU 10 MW turbine which uses AeroDynv14. If I try to use Aerodynv15 with same I get an error. I am using DTU 10 MW because I am trying to reproduce results from paper that used it. I realize that the IEA 10 MW is not an exact replica of the DTU 10 MW so that is also giving me some trouble.
Do you know what should be the format of the TwrFile or can Aerodynv15 be used somehow?
Regards,
AOAW
Dear @Andre.White,
See the “NEWTOWER” documentation and sample tower file provided in the archive of AeroDyn v14.05: https://www.nrel.gov/wind/nwtc/assets/downloads/AeroDyn/AD_v14.05.00a-bjj.exe.
I’m not sure what error you are getting with AeroDyn v15
Best regards,
Thank you. This is the error I get with Aerodyn15:
FAST_InitializeAll:ED_Init:ED_ReadInput:ReadBladeInputs:ReadBladeMeshFileAD:Invalid numerical
input for file “.\10MW_Reference WT\DTU_10MW_RWT_AeroDyn15.dat” occurred while trying to read
Blade element line1.
Regards,
AOAW
Dear @Andre.White,
ElastoDyn SUBROUTINE ReadBladeMeshFileAD() is only called when AeroDyn v14 is enabled. Are you sure you’ve enabled AeroDyn v15 correctly?
Best regards,
Hi @Jason.Jonkman:
That was the error. I did not call AeroDyn15. However, when I did, I received this error.
FAST_InitializeAll:AD_Init:ReadInputFiles:ReadPrimaryFile:Invalid logical input for file
“.\10MW_Reference WT\DTU_10MW_RWT_AeroDyn15.dat” occurred while trying to read TwrShadow.
Regards,
AOAW
Dear @Andre.White,
FAST_InitializeAll:ED_Init:ED_ReadInput:ReadBladeInputs:ReadBladeMeshFileAD:Invalid numerical
input for file “.\10MW_Reference WT\DTU_10MW_RWT_AeroDyn15.dat” occurred while trying to read
Blade element line1.
I suspect you are receiving this error because you have enabled AeroDyn v14 while using an AeroDyn v15 input file.
FAST_InitializeAll:AD_Init:ReadInputFiles:ReadPrimaryFile:Invalid logical input for file
“.\10MW_Reference WT\DTU_10MW_RWT_AeroDyn15.dat” occurred while trying to read TwrShadow.
I suspect you are receiving this error because you have enabled AeroDyn v15, but your AeroDyn v15 input file is not formatted properly for the version of OpenFAST you are running. As with any input file processing error, I would enable the Echo option to debug. Also review the input file change documentation here: 4.1.2. API changes between versions — OpenFAST v3.5.1 documentation.
Best regards,
Thank you @Jason.Jonkman.
When I ran the AeroDyn14 model using Aero_Tower file it worked but I received the following lines at the start, doe it mean I will get wrong results?
Basic DTU Wind Energy Controller (ver. 1.5) loaded…
PIDvar%outres= NaN
PIDvar%outpro= -3.43415051805555
PIDvar%outdif= NaN
dt= 0.000000000000000E+000
PIDvar%error1_old(1)= 0.000000000000000E+000
error(1)= -1.00500000000000
PIDvar%Kdif(1)= 0.000000000000000E+000
Padded_term= 0.000000000000000E+000
PIDvar%outset= 0.000000000000000E+000
Regards,
AOAW
I’m not familiar enough with the DTU controller to comment.
Noted @Jason.Jonkman .
Regards,
AOAW
@Jason.Jonkman is this AeroDynv14 for NREL 5.0 MW baseline? I want to find out if the AeroDyn Tower values would be the same one used by DTU 10 MW if they have used AeroDynv14. For example, the tower diameter and the Cd values would they remain the same?
---------------------- DISTRIBUTED TOWER PROPERTIES ----------------------------
TwrHtFr(-) TwrWid(m) NTwrCDCol(must be 1)
0.00000 6.000 1
0.09733 5.787 1
0.19467 5.574 1
0.29200 5.361 1
0.38933 5.148 1
0.48667 4.935 1
0.58400 4.722 1
0.68133 4.509 1
0.77867 4.296 1
0.87600 4.083 1
0.97333 3.870 1
1.00000 3.870 1
---------------------- Cd v. Re PROPERTIES -------------------------------------
TwrRe TwrCD
0.010 1.11
0.020 1.20
0.122 1.20
0.200 1.17
0.300 0.90
0.400 0.54
0.500 0.31
1.000 0.38
1.500 0.46
2.000 0.53
2.500 0.57
3.000 0.61
3.500 0.64
4.000 0.67
5.000 0.70
10.000 0.70
Regards,
AOAW
Dear @Andre.White,
Yes, the diameter versus normalized tower height data you show are for the NREL 5-MW baseline wind turbine. These properties would certainly change for the DTU 10-MW reference wind turbine.
The drag versus Reynolds number data look like quite generic data for a cylindrical cross section.
Best regards,
Thank you @Jason.Jonkman.
AOAW