FAST8 Linearization

Dear Taha,

Are you attempting to use AeroDyn v14 or AeroDyn v15 within FAST v8? Your first attachment is an AeroDyn v14 input file whereas the third attachment is an AeroDyn v15 input file. Your second attachment is an airfoil data file formatted for AeroDyn v14.

The error you are receiving would be triggered by using an AeroDyn input file formatted for v15, but identified as v14 in the FAST primary input file (CompAero=1 selects v14 and CompAero=2 selects v15).

Best regards,

Dear Jason,

yes, Thank you. I have solved this error but now when I use Aerodyn v15, I recieve this error

Running AeroDyn (v15.03.00, 27-Jul-2016).

FAST_InitializeAll:AD_Init:ReadInputFiles:ReadPrimaryFile:Invalid numerical input for file
“D:\FAST1\FAST8\CertTest\WP_Baseline/WP_Baseline_AeroDyn15_Dynin.dat” occurred while trying to
read TwrNds.
ReadPrimaryFile:Invalid numerical input for file
“D:\FAST1\FAST8\CertTest\WP_Baseline/WP_Baseline_AeroDyn15_Dynin.dat” occurred while trying to
read TwrNds.
FAST encountered an error during module initialization.
Simulation error level: FATAL ERROR

Aborting FAST.

Best Regards,
Taha

Dear Taha,

I did notice that the first line in your tower nodes table has a TwrElev of 60 whereas the second node is 1.30. This will cause a problem because TwrElev must be specified in monotonically increasing order–from the lowest (tower-base) to the highest (tower-top) elevation. You can also enable the Echo flag in AeroDyn v15 to debug problems in your input file.

Best regards,

Dear Jason,

Thank you, I have solved it. now my dll Controller is working well in case if using Aerodyn V14 but in case If used Aerodynm 15 it gives me this error:-

Running ServoDyn (v1.06.00a-bjj, 26-Jul-2016).

Running ServoDyn Interface for Bladed Controllers (using Intel Visual Fortran f or Windows, 14-Oct-2015).

FAST_InitializeAll:InitModuleMappings:ED_L_2_AD_L_T:MeshMapCreate:CreateMotionMa
p_L2_to_L2:CreateM
apping_ProjectToLine2:Node 43 does not project onto any line2 element.
FAST encountered an error during module initialization.
Simulation error level: FATAL ERROR

Aborting FAST.

Could you please tell me, How can I solve this error?

Best Regards
Taha

Dear Taha,

It appears that FAST is aborting because of an error in the mesh-mapping search for ED_L_2_AD_L_T, which is the mesh-mapping search between the ElastoDyn Line2 tower motion output mesh and the AeroDyn Line2 tower motion input mesh. FAST will trigger this error e.g. if the tower in AeroDyn starts lower than the tower in ElastoDyn or if the tower in AeroDyn ends higher than the tower in ElastoDyn. This error has been discussed on this forum before e.g. here: Meshing error? - #2 by Jason.Jonkman.

I hope that helps.

Best regards,

Dear Jason,

Sorry, I tried to run the Simulation and now I has this error

Running AeroDyn (v15.03.00, 27-Jul-2016).

FAST_InitializeAll:AD_Init:ReadInputFiles:Blade1:ReadBladeInputs:Invalid numeric
al input for file
“D:\FAST1\FAST8\CertTest\WP_Baseline/blade15.dat” occurred while trying to read
Blade properties
row 1.

Here is my blade file and Aerodynmic 15 files.

Best Regards
Taha

Dear Taha,

Your blade15.txt file is formatted for ElastoDyn, not AeroDyn. See the NRELOffshrBsline5MW_AeroDyn_blade.dat file in the Certest/5MW_Baseline directory of the FAST v8 archive for an example blade file formatted for AeroDyn v15.

Best regards,

Dear Jason,

Thank you. the Simulation is runng well with Aerodyn v14 and Aerodyn v15. Now I want to plot my results. I have run the Simulation with Fast 7 and I want to use PlotCertTestResults.m . but I don’t know How can I entre the Inputs for this script.
( newpath, oldpath, plotFASt, plotAdams, plotSimulink ) . Could you please Show me an example for this or any help?

Best Regards
Taha

Dear Taha,

The MATLAB script PlotCertTestResults.m is really meant for comparing new and old solutions from FAST, FAST-generated ADAMS models, and FAST-Simulink models from the FAST CertTest. If you want to compare multiple FAST output files for a given simulation, I would use the MATLAB script PlotFASToutput.m from the MATLAB Toolbox. The arguments to PlotFASToutput.m are well documented in its header.

Best regards,

I have used the MATLAB script PlotFASToutput.m with FAST and I got this error

undefined fuction or variable ‘FASTfilesDesc’

evenif this Input is optional.

Best regards
Taha

Dear Taha,

Can you clarify how you called PlotFASToutput.m when this error was triggered?

Best regards,

Dear Jason

I have copied it from FAST 8 to FAST 7 then I add all FAST 7 to the matlab Path then I run it.

PlotFASToutput({‘…/…/Fast executive/Lasten_1000_1.0.out’},FASTfilesDesc,ReferenceFile,Channels,ShowLegend,CustomHdr,PlotPSDs, OnePlot)
Undefined function or variable ‘FASTfilesDesc’…

Best Regards

Taha

Dear Taha,

The optional arguments should be dropped from the argument list if not used i.e. call:

PlotFASToutput({'../../Fast executive/Lasten_1000_1.0.out'})

Best regards,

Dear Jason,

I have got other error.

PlotFASToutput({‘…/…/Fast executive/Lasten_1000_1.0.out’})
ReadFASTtext::Error -1 reading from file, “…/…/Fast executive/Lasten_1000_1.0.out”
Index exceeds matrix dimensions.
Error in PlotFASToutput (line 93)
if length(FASTfiles{iFile}) > 4 && strcmpi( FASTfiles{iFile}((end-4):end),‘.outb’ )

Best Regards,
Taha

Dear Taha,

Receiving “Error -1” means that the name of the FAST output file, or the path to it, is wrong.

Best regards,

Dear Jason,

I have a question regarding the linearization. I have linearized my wind turbine at region 3 ( wind speed above rated speed ). I have adjusted the initial pitch angel and the rotor speed at the primary input file. After I have done the linearization 36 times and I took the average, I found that the output rotor speed from the linear model is higher than the rated speed which I have put as initial speed. I don’t know why ?

Sorry for my more questions.
Regards,
Taha Fouda

Dear Taha,

I’m not sure I really understand your question; are you referring to the operating point rotor speed or the rotor speed resulting from some time-domain integration of the linearized system? If the former, I suggest that you always review the time series before using the linearized solution to ensure that the time series is in a steady state or periodic steady state condition during the linearization process.

Best regards,

Dear Jason,

I am doing the linearization of my turbine model at region 3 ( wind speed above rated speed ). I have defined the trim conditions at the primary input files.
the problem now is:-

  • when I compare the linear response with the nonlinear response for the rotational speed . it shows different response at the first 10 sec before the change the pitch.
  • why the linear response starts from 28.1 rpm and I have defined the trim rpm at 19 rpm.
  • the blue line the linear and the yellow line is the nonliear.
  • what do you mean by the time series?

Regards
Taha

Dear Taha,

I’m sorry, but I don’t understand enough about what you are doing to answer answer your question.

When I referred to “time series” in my prior post, I was referring to the time-domain simulation that FAST v8 is solving before linearizing at various LinTimes.

Best regards,

Dear Jason,

Maybe I have found from where my Problem Comes. I have my own Generator model and control and I Need to do the linearization process. to do that I have to set GenModel 1 or 2. I can’t set it to 3 to call my Generator Routine.

I have run the time-Domain Simulation with my DLL Controller and my Generator subroutine. it gives me the result which I expect.

So what should I do to linearize for my Generator model?

Best regards,
Taha