Turning off Unsteady aerodynamics and no valid value of phi.

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Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Jason.Jonkman » Mon Apr 06, 2020 6:54 am

Dear Dhaneesh,

The AeroDyn input file format changed between FAST v8.16 and OpenFAST v1.0. You can review what in the input has changed in the OpenFAST documentation--see: https://openfast.readthedocs.io/en/mast ... hange.html. You can also use the Echo option from the AeroDyn input file to debug errors in the input-file processing.

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

Dhaneesh.Machavarapu
Posts: 56
Joined: Sat Feb 29, 2020 9:56 am
Organization: NITcalicut
Location: INDIA

Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Dhaneesh.Machavarapu » Mon Apr 06, 2020 1:33 pm

Sir,

As per your suggestion I used echo option in aerodyn input file. And the echo file I got was this.


This file of echoed input was generated by AeroDyn on 07-Apr-2020 at 00:34:50.

Data from AeroDyn primary input file "E:/softwares/Project/openfast/offshore/5MW_OC3Mnpl_DLL_WTurb_WavesIrr/NRELOffshrBsline5MW_OC3Monopile_AeroDyn15.dat":


FTitle - File Header: File Description (line 2)
"NREL 5.0 MW offshore baseline aerodynamic input properties, with OC3 Monopile tower"

T Echo - Echo flag
DTAero - Time interval for aerodynamic calculations {or default} (s)
"default"
1 WakeMod - Type of wake/induction model {0=none, 1=BEMT} (-)
2 AFAeroMod - Type of airfoil aerodynamics model {1=steady model, 2=Beddoes-Leishman unsteady model} (-)
1 TwrPotent - Type tower influence on wind based on potential flow around the tower {0=none, 1=baseline potential flow, 2=potential flow with Bak correction} (-)
F TwrShadow - Calculate tower influence on wind based on downstream tower shadow? (flag)
T TwrAero - Calculate tower aerodynamic loads? (flag)
F FrozenWake - Assume frozen wake during linearization? (flag)
F CavitCheck - Perform cavitation check? (flag)

1.2250E+00 AirDens - Air density (kg/m^3)
1.4640E-05 KinVisc - Kinematic air viscosity (m^2/s)
3.3500E+02 SpdSound - Speed of sound (m/s)
1.0350E+05 Patm - Atmospheric pressure (Pa)
1.7000E+03 Pvap - Vapour pressure of fluid (Pa)
5.0000E-01 FluidDepth - Water depth above mid-hub height (MHK only, for cavitation check) (m)

2 SkewMod - Type of skewed-wake correction model {1=uncoupled, 2=Pitt/Peters, 3=coupled} [used only when WakeMod=1] (-)
T HubLoss - Use the Prandtl hub-loss model? [used only when WakeMod=1] (flag)
T TanInd - Include tangential induction in BEMT calculations? [used only when WakeMod=1] (flag)
T AIDrag - Include the drag term in the axial-induction calculation? [used only when WakeMod=1] (flag)
F TIDrag - Include the drag term in the tangential-induction calculation? [used only when WakeMod=1 and TanInd=TRUE] (flag)
IndToler - Convergence tolerance for BEM induction factors [used only when WakeMod=1] (-)
"False"

I got glue codes for OPENFAST form https://github.com/openfast/r-test. In that there was no source F90 files like in previous versions of FAST. Was it the reason?
If it is can I get some help where I can get that.

Jason.Jonkman
Posts: 4858
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
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Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Jason.Jonkman » Mon Apr 06, 2020 2:26 pm

Dear Dhaneesh,

The Echo file can be used to check that data read into OpenFAST matches what you specified in the input file(s) so as to debug errors in the input file formatting. Are the values you showing matching what you specified in the input file? I'm not sure why, but I don't see TipLoss in you Echo file. Do you copy/paste the contents of the whole echo file? It also looks like IndToler is set to "False", instead of a "DEFAULT" or a number, which doesn't look right.

In FAST v8, the archive contained the source code, compiled executable, and sample models (CertTest). In OpenFAST, the source code is contained in: https://github.com/OpenFAST/openfast, the sample models (r-test) are stored separately: https://github.com/OpenFAST/r-test, and the compiled executables are available separately: https://github.com/OpenFAST/openfast/releases.

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

Dhaneesh.Machavarapu
Posts: 56
Joined: Sat Feb 29, 2020 9:56 am
Organization: NITcalicut
Location: INDIA

Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Dhaneesh.Machavarapu » Mon Apr 13, 2020 5:24 am

Sir,

I have downloaded r-test files and compiled executables and made a copy of my work files(5MW_Baseline and 5MW_OC3Mnpl_DLL_WTurb_WavesIrr)
in seperate folder and tried to run it in command prompt then it was showing that there was a installation problem. Is openfast have a installation procedure or is it similar to that of FAST v8.16 . Because when I tried to run it like before it was not working .

Jason.Jonkman
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Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Jason.Jonkman » Mon Apr 13, 2020 7:02 am

Dear Dhaneesh,

What do you mean by "installation problem". What error are you receiving?

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

Dhaneesh.Machavarapu
Posts: 56
Joined: Sat Feb 29, 2020 9:56 am
Organization: NITcalicut
Location: INDIA

Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Dhaneesh.Machavarapu » Mon Apr 13, 2020 9:50 am

Sir,

When I tried to run openfast on command prompt window openfast didn't run and showed an error message that reinstalling the code may solve the problem. Then I changed my work file directory and tried to run it. And I again got this error.

C:\Users\Bhargav>E:\softwares\Project\openfast\offshore\openfast_x64.exe E:\softwares\Project\openfast\offshore\5MW_OC3Mnpl_DLL_WTurb_WavesIrr.fst

**************************************************************************************************
OpenFAST

Copyright (C) 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.
**************************************************************************************************

OpenFAST-v1.0.0-dirty
Compile Info:
- Architecture: 64 bit
- Precision: single
Execution Info:
- Date: 04/13/2020
- Time: 20:24:35+0530

OpenFAST input file heading:
FAST Certification Test #19: NREL 5.0 MW Baseline Wind Turbine with OC3 Monopile RF
Configuration, for use in offshore analysis

Running ElastoDyn.
Running AeroDyn.

FAST_InitializeAll:AD_Init:ReadInputFiles:ReadPrimaryFile:Invalid logical input for file
"E:/softwares/Project/openfast/offshore/5MW_Baseline/NRELOffshrBsline5MW_OC3Monopile_AeroDyn15.dat
" occurred while trying to read TipLoss.
ReadPrimaryFile:Invalid numerical input for file
"E:/softwares/Project/openfast/offshore/5MW_Baseline/NRELOffshrBsline5MW_OC3Monopile_AeroDyn15.dat
" occurred while trying to read IndToler.
ReadPrimaryFile:Invalid numerical input for file
"E:/softwares/Project/openfast/offshore/5MW_Baseline/NRELOffshrBsline5MW_OC3Monopile_AeroDyn15.dat
" occurred while trying to read MaxIter.

FAST encountered an error during module initialization.
Simulation error level: FATAL ERROR

Aborting OpenFAST.

And the Aerodyn input file I used was

------- AERODYN v15 for OpenFAST INPUT FILE -----------------------------------------------
NREL 5.0 MW offshore baseline aerodynamic input properties, with OC3 Monopile tower
====== General Options ============================================================================
True Echo - Echo the input to "<rootname>.AD.ech"? (flag)
"default" DTAero - Time interval for aerodynamic calculations {or "default"} (s)
1 WakeMod - Type of wake/induction model (switch) {0=none, 1=BEMT, 2=DBEMT} [WakeMod cannot be 2 when linearizing]
2 AFAeroMod - Type of blade airfoil aerodynamics model (switch) {1=steady model, 2=Beddoes-Leishman unsteady model} [AFAeroMod must be 1 when linearizing]
1 TwrPotent - Type tower influence on wind based on potential flow around the tower (switch) {0=none, 1=baseline potential flow, 2=potential flow with Bak correction}
False TwrShadow - Calculate tower influence on wind based on downstream tower shadow? (flag)
True TwrAero - Calculate tower aerodynamic loads? (flag)
False FrozenWake - Assume frozen wake during linearization? (flag) [used only when WakeMod=1 and when linearizing]
False CavitCheck - Perform cavitation check? (flag) [AFAeroMod must be 1 when CavitCheck=true]
====== Environmental Conditions ===================================================================
1.225 AirDens - Air density (kg/m^3)
1.464E-05 KinVisc - Kinematic air viscosity (m^2/s)
335 SpdSound - Speed of sound (m/s)
103500 Patm - Atmospheric pressure (Pa) [used only when CavitCheck=True]
1700 Pvap - Vapour pressure of fluid (Pa) [used only when CavitCheck=True]
0.5 FluidDepth - Water depth above mid-hub height (m) [used only when CavitCheck=True]
====== Blade-Element/Momentum Theory Options ====================================================== [unused when WakeMod=0]
2 SkewMod - Type of skewed-wake correction model (switch) {1=uncoupled, 2=Pitt/Peters, 3=coupled} [unused when WakeMod=0]
"default" SkewModFactor - Constant used in Pitt/Peters skewed wake model {or "default" is 15/32*pi} (-) [used only when SkewMod=2; unused when WakeMod=0]
True TipLoss - Use the Prandtl tip-loss model? (flag) [unused when WakeMod=0]
True HubLoss - Use the Prandtl hub-loss model? (flag) [unused when WakeMod=0]
true TanInd - Include tangential induction in BEMT calculations? (flag) [unused when WakeMod=0]
False AIDrag - Include the drag term in the axial-induction calculation? (flag) [unused when WakeMod=0]
False TIDrag - Include the drag term in the tangential-induction calculation? (flag) [unused when WakeMod=0 or TanInd=FALSE]
"Default" IndToler - Convergence tolerance for BEMT nonlinear solve residual equation {or "default"} (-) [unused when WakeMod=0]
100 MaxIter - Maximum number of iteration steps (-) [unused when WakeMod=0]
====== Dynamic Blade-Element/Momentum Theory Options ============================================== [used only when WakeMod=2]
2 DBEMT_Mod - Type of dynamic BEMT (DBEMT) model {1=constant tau1, 2=time-dependent tau1} (-) [used only when WakeMod=2]
4 tau1_const - Time constant for DBEMT (s) [used only when WakeMod=2 and DBEMT_Mod=1]
====== Beddoes-Leishman Unsteady Airfoil Aerodynamics Options ===================================== [used only when AFAeroMod=2]
3 UAMod - Unsteady Aero Model Switch (switch) {1=Baseline model (Original), 2=Gonzalez's variant (changes in Cn,Cc,Cm), 3=Minemma/Pierce variant (changes in Cc and Cm)} [used only when AFAeroMod=2]
True FLookup - Flag to indicate whether a lookup for f' will be calculated (TRUE) or whether best-fit exponential equations will be used (FALSE); if FALSE S1-S4 must be provided in airfoil input files (flag) [used only when AFAeroMod=2]
====== Airfoil Information =========================================================================
1 AFTabMod - Interpolation method for multiple airfoil tables {1=1D interpolation on AoA (first table only); 2=2D interpolation on AoA and Re; 3=2D interpolation on AoA and UserProp} (-)
1 InCol_Alfa - The column in the airfoil tables that contains the angle of attack (-)
2 InCol_Cl - The column in the airfoil tables that contains the lift coefficient (-)
3 InCol_Cd - The column in the airfoil tables that contains the drag coefficient (-)
4 InCol_Cm - The column in the airfoil tables that contains the pitching-moment coefficient; use zero if there is no Cm column (-)
0 InCol_Cpmin - The column in the airfoil tables that contains the Cpmin coefficient; use zero if there is no Cpmin column (-)
8 NumAFfiles - Number of airfoil files used (-)
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/Cylinder1.dat" AFNames - Airfoil file names (NumAFfiles lines) (quoted strings)
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/Cylinder2.dat"
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/DU40_A17.dat"
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/DU35_A17.dat"
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/DU30_A17.dat"
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/DU25_A17.dat"
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/DU21_A17.dat"
"E:/softwares/Project/openfast/offshore/5MW_Baseline/Airfoils/NACA64_A17.dat"
====== Rotor/Blade Properties =====================================================================
True UseBlCm - Include aerodynamic pitching moment in calculations? (flag)
"E:/softwares/Project/openfast/offshore/5MW_Baseline/NRELOffshrBsline5MW_AeroDyn_blade.dat" ADBlFile(1) - Name of file containing distributed aerodynamic properties for Blade #1 (-)
"E:/softwares/Project/openfast/offshore/5MW_Baseline/NRELOffshrBsline5MW_AeroDyn_blade.dat" ADBlFile(2) - Name of file containing distributed aerodynamic properties for Blade #2 (-) [unused if NumBl < 2]
"E:/softwares/Project/openfast/offshore/5MW_Baseline/NRELOffshrBsline5MW_AeroDyn_blade.dat" ADBlFile(3) - Name of file containing distributed aerodynamic properties for Blade #3 (-) [unused if NumBl < 3]
====== Tower Influence and Aerodynamics ============================================================= [used only when TwrPotent/=0, TwrShadow=True, or TwrAero=True]
11 NumTwrNds - Number of tower nodes used in the analysis (-) [used only when TwrPotent/=0, TwrShadow=True, or TwrAero=True]
TwrElev TwrDiam TwrCd
(m) (m) (-)
1.0000000E+01 6.0000000E+00 1.0000000E+00
1.7760000E+01 5.7870000E+00 1.0000000E+00
2.5520000E+01 5.5740000E+00 1.0000000E+00
3.3280000E+01 5.3610000E+00 1.0000000E+00
4.1040000E+01 5.1480000E+00 1.0000000E+00
4.8800000E+01 4.9350000E+00 1.0000000E+00
5.6560000E+01 4.7220000E+00 1.0000000E+00
6.4320000E+01 4.5090000E+00 1.0000000E+00
7.2080000E+01 4.2960000E+00 1.0000000E+00
7.9840000E+01 4.0830000E+00 1.0000000E+00
8.7600000E+01 3.8700000E+00 1.0000000E+00
====== Outputs ====================================================================================
True SumPrint - Generate a summary file listing input options and interpolated properties to "<rootname>.AD.sum"? (flag)
0 NBlOuts - Number of blade node outputs [0 - 9] (-)
2, 9, 16, 4, 5, 7, 11, 13, 14 BlOutNd - Blade nodes whose values will be output (-)
0 NTwOuts - Number of tower node outputs [0 - 9] (-)
1, 2, 3, 4, 5 TwOutNd - Tower nodes whose values will be output (-)
OutList - The next line(s) contains a list of output parameters. See OutListParameters.xlsx for a listing of available output channels, (-)
"RtAeroFxh, RtAeroFyh, RtAeroFzh"
"RtAeroMxh, RtAeroMyh, RtAeroMzh"
END of input file (the word "END" must appear in the first 3 columns of this last OutList line)
---------------------------------------------------------------------------------------

And Aerodyn echo file I got was


This file of echoed input was generated by AeroDyn on 13-Apr-2020 at 20:24:36.

Data from AeroDyn primary input file "E:/softwares/Project/openfast/offshore/5MW_Baseline/NRELOffshrBsline5MW_OC3Monopile_AeroDyn15.dat":


FTitle - File Header: File Description (line 2)
"NREL 5.0 MW offshore baseline aerodynamic input properties, with OC3 Monopile tower"

T Echo - Echo flag
DTAero - Time interval for aerodynamic calculations {or default} (s)
"default"
1 WakeMod - Type of wake/induction model {0=none, 1=BEMT} (-)
2 AFAeroMod - Type of airfoil aerodynamics model {1=steady model, 2=Beddoes-Leishman unsteady model} (-)
1 TwrPotent - Type tower influence on wind based on potential flow around the tower {0=none, 1=baseline potential flow, 2=potential flow with Bak correction} (-)
F TwrShadow - Calculate tower influence on wind based on downstream tower shadow? (flag)
T TwrAero - Calculate tower aerodynamic loads? (flag)
F FrozenWake - Assume frozen wake during linearization? (flag)
F CavitCheck - Perform cavitation check? (flag)

1.2250E+00 AirDens - Air density (kg/m^3)
1.4640E-05 KinVisc - Kinematic air viscosity (m^2/s)
3.3500E+02 SpdSound - Speed of sound (m/s)
1.0350E+05 Patm - Atmospheric pressure (Pa)
1.7000E+03 Pvap - Vapour pressure of fluid (Pa)
5.0000E-01 FluidDepth - Water depth above mid-hub height (MHK only, for cavitation check) (m)

2 SkewMod - Type of skewed-wake correction model {1=uncoupled, 2=Pitt/Peters, 3=coupled} [used only when WakeMod=1] (-)
T HubLoss - Use the Prandtl hub-loss model? [used only when WakeMod=1] (flag)
T TanInd - Include tangential induction in BEMT calculations? [used only when WakeMod=1] (flag)
T AIDrag - Include the drag term in the axial-induction calculation? [used only when WakeMod=1] (flag)
F TIDrag - Include the drag term in the tangential-induction calculation? [used only when WakeMod=1 and TanInd=TRUE] (flag)
IndToler - Convergence tolerance for BEM induction factors [used only when WakeMod=1] (-)
"False"

And in echo file tiploss was missing and IndToler was set as False. But in Aerodyn file it was set as default.

Jason.Jonkman
Posts: 4858
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Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Jason.Jonkman » Mon Apr 13, 2020 11:21 am

Dear Dhaneesh,

From these files, I would guess that you downloaded the r-test for the newest version of OpenFAST (v2.3), but you are using an older version of OpenFAST (1.0). You can either upgrade OpenFAST to v2.3 (https://github.com/OpenFAST/openfast/releases) or download the r-test associated with OpenFAST v1.0 (https://github.com/OpenFAST/r-test/releases).

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

Dhaneesh.Machavarapu
Posts: 56
Joined: Sat Feb 29, 2020 9:56 am
Organization: NITcalicut
Location: INDIA

Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Dhaneesh.Machavarapu » Mon Apr 13, 2020 11:29 pm

Sir,

I have upgraded openfast to v2.3 and tried to run it. Then openfast_Win32.exe was showing System Error like this.

The code execution cannot proceed because libifportMD.dll, libmmd.dll, libifcoremd.dll, svml_dispmd.dll were not found. Reinstalling the program
may fix this problem.

This was the system error message I got.

Jason.Jonkman
Posts: 4858
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Jason.Jonkman » Tue Apr 14, 2020 6:59 am

Dear Dhaneesh,

The question on how to resolve an error regarding libifcoremd.dll etc. has been answered on OpenFAST issues: https://github.com/OpenFAST/openfast/issues/352.

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

Dhaneesh.Machavarapu
Posts: 56
Joined: Sat Feb 29, 2020 9:56 am
Organization: NITcalicut
Location: INDIA

Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Dhaneesh.Machavarapu » Thu Apr 16, 2020 10:18 am

Sir,

Thank you for your suggestions and now I am able to run openfast. OPenfast has terminated normally but still I was getting warnings eventhough I was using aerodyn v15.04 version. So how can I overcome that warnings.

**************************************************************************************************
OpenFAST

Copyright (C) National Renewable Energy Laboratory
Copyright (C) Envision Energy USA LTD

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.
**************************************************************************************************

OpenFAST-v2.3.0
Compile Info:
- Architecture: 32 bit
- Precision: single
- Date: Apr 03 2020
- Time: 14:10:27
Execution Info:
- Date: 04/16/2020
- Time: 21:25:31+0530

OpenFAST input file heading:
FAST Certification Test #19: NREL 5.0 MW Baseline Wind Turbine with OC3 Monopile RF
Configuration, for use in offshore analysis

Running ElastoDyn.
Running AeroDyn.
Running BEM.
Running UnsteadyAero.
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 1, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 2, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 3, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 4, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 1, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 2, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 3, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 4, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 1, Blade = 3
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 2, Blade = 3
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 3, Blade = 3
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 4, Blade = 3
Running InflowWind.

Reading a 31x31 grid (145 m wide, 17.5 m to 162.5 m above ground) with a characteristic wind
speed of 12 m/s. This full-field file was generated by TurbSim (v1.06.00, 21-Sep-2012) on
28-Mar-2020 at 15:16:21.

Processed 12842 time steps of 20-Hz full-field data (642.05 seconds).
Running ServoDyn.
Running ServoDyn Interface for Bladed Controllers.
Running HydroDyn.
Generating incident wave kinematics and current time history.
Calculating second order difference frequency wave kinematics.
Calculating second order sum frequency wave kinematics.
M2N3FDxi is not an available output channel.
M2N3FDyi is not an available output channel.
M2N3FDzi is not an available output channel.
M2N3FIxi is not an available output channel.
M2N3FIyi is not an available output channel.
M2N3FIzi is not an available output channel.
Running SubDyn.
Calculating Internal Modal Eigenvectors
Time: 0 of 630 seconds.

FAST_Solution0:CalcOutputs_And_SolveForInputs:SolveOption2:SrvD_CalcOutput:Running with torque
and pitch control of the NREL offshore 5MW baseline wind turbine from DISCON.dll as written by J.
Jonkman of NREL/NWTC for use in the IEA Annex XXIII OC3 studies.


Total Real Time: 12.186 minutes
Total CPU Time: 11.299 minutes
Simulation CPU Time: 9.7563 minutes
Simulated Time: 10.5 minutes
Time Ratio (Sim/CPU): 1.0762

OpenFAST terminated normally.

Thank you.

Jason.Jonkman
Posts: 4858
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: Turning off Unsteady aerodynamics and no valid value of phi.

Postby Jason.Jonkman » Thu Apr 16, 2020 12:51 pm

Dear Dhaneesh,

The warnings about "turning off unsteady aerodynamics" applies to the unsteady airfoil aerodynamics (UA, dynamic stall) model for the first 4 nodes of each blade, which are the root / cylindrical sections of the airfoil where the UA model is not valid. The warnings are not indicating a problem with the simulation, but are expected in this case.

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


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