Hello everyone,
I am new to OpenFAST and would like to use the IEA-3.4-130-RWT for my master thesis. However, I am struggling to get it running properly. For some context, I installed OpenFAST v3.5.0 and rosco v2.7.0 using anaconda on Debian. Since there have been some changes to the RWT recently, I should say that I had the same problems with the previous version (using OF v3.4.0/1 and rosco 2.6.0).
Using all the defaults of the model, OpenFAST crashes after about 30s with the following output:
**************************************************************************************************
OpenFAST
Copyright (C) 2023 National Renewable Energy Laboratory
Copyright (C) 2023 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--128-NOTFOUND
Compile Info:
- Compiler: GCC version 12.2.0
- Architecture: 64 bit
- Precision: single
- OpenMP: No
- Date: May 17 2023
- Time: 10:23:29
Execution Info:
- Date: 06/06/2023
- Time: 16:43:16+0200
OpenFAST input file heading:
Generated with AeroElasticSE FAST driver
Running ElastoDyn.
Nodal outputs section of ElastoDyn input file not found or improperly formatted.
Running AeroDyn.
AD15 Nodal Outputs: Nodal output section of AeroDyn input file not found or improperly formatted.
Skipping nodal outputs.
Warning: Turning off Unsteady Aerodynamics because polar has constant data. (node 1, blade 1)
Warning: Turning off Unsteady Aerodynamics because polar has constant data. (node 1, blade 2)
Warning: Turning off Unsteady Aerodynamics because polar has constant data. (node 1, blade 3)
Running InflowWind.
Running ServoDyn.
Running ServoDyn Interface for Bladed Controllers (using GNU Fortran for Linux).
Using legacy Bladed DLL interface.
Time: 0 of 60 seconds.
------------------------------------------------------------------------------
Running ROSCO-v2.7.0
A wind turbine controller framework for public use in the scientific field
Developed in collaboration: National Renewable Energy Laboratory
Delft University of Technology, The Netherlands
------------------------------------------------------------------------------
Generator speed: 1140.0 RPM, Pitch angle: 3.3 deg, Power: 0.0 kW, Est. wind Speed: 10.0 m/s
FAST_Solution:CalcOutputs_And_SolveForInputs:SolveOption2:AD_CalcOutput:RotCalcOutput:BEMT_CalcOut
put(node 2, blade 3):UA_CalcOutput:UA_BlendSteady:Temporarily turning off UA due to high angle of
attack or low relative velocity. This warning will not be repeated though the condition may
persist.
Warning: SkewedWakeCorrection encountered a large value of chi (90.637 deg), so the yaw
correction will be limited. This warning will not be repeated though the condition may persist.
See the AD15 chi output channels, and consider turning off the Pitt/Peters skew model (set
SkewMod=1) if this condition persists.
FAST_Solution:FAST_AdvanceStates:AD_UpdateStates:BEMT_UpdateStates:UpdatePhi(node 3, blade
1):BEMT_UnCoupledSolve:There is no valid value of phi for these operating conditions: Vx =
1.60879E-02, Vy = -2.324, rlocal = 6.3296, theta = 0.38327, geometric phi = 3.1347. This warning
will not be repeated though the condition may persist. (See GeomPhi output channel.)
FAST_Solution:CalcOutputs_And_SolveForInputs:SolveOption2:AD_CalcOutput:RotCalcOutput:BEMT_CalcOut
put(node 30, blade 3):UA_CalcOutput:Mach number exceeds 0.3. Theory is invalid. This warning will
not be repeated though the condition may persist.
FAST_Solution:FAST_AdvanceStates:ED_ABM4:ED_CalcContStateDeriv:SetCoordSy:Small angle assumption
violated in SUBROUTINE SmllRotTrans() due to a large platform displacement (ElastoDyn
SetCoordSy). The solution may be inaccurate. Simulation continuing, but future warnings from
SmllRotTrans() will be suppressed.
Additional debugging message from SUBROUTINE SmllRotTrans(): 6.59 s
Generator speed: 805.0 RPM, Pitch angle: 0.0 deg, Power: 1639.1 kW, Est. wind Speed: 6.7 m/s
Time: 10 of 60 seconds. Estimated final completion at 16:43:33. Generator speed: 868.8 RPM, Pitch angle: 0.0 deg, Power: 2002.3 kW, Est. wind Speed: 8.9 m/s
Time: 20 of 60 seconds. Estimated final completion at 16:43:34.
FAST_Solution:CalcOutputs_And_SolveForInputs:SolveOption2:AD_CalcOutput:RotCalcOutput:BEMT_CalcOut
put(node 30, blade 1):UA_CalcOutput:Mach number exceeds 1.0. Equations cannot be evaluated.
OpenFAST encountered an error at simulation time 27.29 of 60 seconds.
Simulation error level: FATAL ERROR
I’ve attempted some of the solutions that were already suggested in this forum:
- setting reasonable starting values for omega and the pitch angle (11.75 rpm and 3.33° @ 10 m/s Wind → according to the lookup table of the RWT)
- using smaller time steps
- enabling correction steps
These changes had no effect. When I disable unsteady aerodynamics (AFAeroMod=1) the simulation gets stuck at around 70 seconds, but does not abort with an error. By setting SkewMod=1 the related warning in the output disappears, but the simulation still crashes after roughly 30s.
I looked at the output data and noticed some unexpected behaviour. Although the wind speed should remain steady at 10 m/s, it drops to zero after only 5 seconds of simulation. Meanwhile, the power remains non-zero throughout the simulation (as a new user, I can only upload one image).
I would appreciate any help or suggestions to get the model running. Thanks in advance!
Best regards,
Alex
