OpenFAST simulation of 15MW Floater: IEA-15-240-RWT-UMaineSemi

[HansiLeMann]

I am trying to run a simulation of the UMaine VolturnUS-S (FOWT) semi-submersible supporting the IEA-15-240-RWT wind turbine: https://github.com/IEAWindTask37/IEA-15-240-RWT/tree/master/OpenFAST/IEA-15-240-RWT-UMaineSemi

I am new to OpenFAST but have successfully been running test cases like the _5MW_OC4Semi_WStWavesWN with the approach described in: https://www.youtube.com/watch?v=I8TP84swWZE&t=382s&ab_channel=NavalArchipelago

When I run the IEA-15-240-RWT-UMaineSemi.fst via _openfastx64.exe I get the following result:

OpenFAST-v3.3.0
Compile Info:
 - Compiler: Intel(R) Fortran Compiler 1900
 - Architecture: 64 bit
 - Precision: single
 - OpenMP: No
 - Date: Nov 02 2022
 - Time: 14:07:06
Execution Info:
 - Date: 01/02/2023
 - Time: 17:52:55+0100

OpenFAST input file heading:
    IEA 15 MW offshore reference model on UMaine VolturnUS-S semi-submersible floating platform

Running ElastoDyn.
Running AeroDyn.
Warning: Turning off Unsteady Aerodynamics because UA parameters are not included in airfoil
(airfoil has likely has constant polars). (node 1, blade 1)
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. (node 2, blade 1)
[...]
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. (node 5, blade 3)
Running InflowWind.
Running HydroDyn.
  WARNING:  The requested output channel is invalid: WavesF1xi
  [...]
  WARNING:  The requested output channel is invalid: WavesM2zi
 Generating incident wave kinematics and current time history.
 Calculating second order difference frequency wave kinematics.
 Calculating second order sum frequency wave kinematics.
 Reading in WAMIT output with root name ".\HydroData/IEA-15-240-RWT-UMaineSemi".
 Computing radiation impulse response functions and wave diffraction forces.
 Calculating second order difference-frequency force using the full quadratic transfer function.
Running MoorDyn (v2.a27, 2022-07-20).
   This is an alpha version of MoorDyn-F v2, with significant input file changes from v1.
   Copyright: (C) 2021 National Renewable Energy Laboratory, (C) 2019 Matt Hall
   Parsing MoorDyn input file: .\IEA-15-240-RWT-UMaineSemi_MoorDyn.dat
Warning: invalid output specifier FX.  Must start with L, C, R, or B
Warning: invalid output specifier FY.  Must start with L, C, R, or B
Warning: invalid output specifier FZ.  Must start with L, C, R, or B
   Created mooring system:  3 lines, 6 points, 0 rods, 0 bodies.
   Finalizing initial conditions using dynamic relaxation.
   t=1  FairTen 1: 3.68647E+06, 1, 2                                                             
   t=2  FairTen 1: 1.84869E+06, 3.68647E+06, 1                                                    
   [...]  
   t=60  FairTen 1: 2.43287E+06, 2.44526E+06, 2.43537E+06
   Fairlead tensions did not converge within TMaxIC=60 seconds.
   MoorDyn initialization completed.
Running ServoDyn.
Running ServoDyn Interface for Bladed Controllers (using Intel Visual Fortran for Windows).

FAST_InitializeAll:HydroDyn_Init:HydroDynInput_ProcessInitData: A requested output channel is
invalid
FAST_InitializeAll:SrvD_Init:BladedInterface_Init:The dynamic library
.\../IEA-15-240-RWT/ServoData/libdiscon.so could not be loaded. Check that the file exists in the
specified location and that it is compiled for 64-bit applications.

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

 Aborting OpenFAST.

I have installed ROSCO to my raft-env.

I hope that you can help.

[bjonkman]

The error message indicates that the controller dynamic library you specified in ServoDyn, .\../IEA-15-240-RWT/ServoData/libdiscon.so, either (1) doesn't exist (at least in that file location) or (2) it does exist but is not built for the same architecture as you are running the simulation on.

Are you running this on Windows? If so, you likely need a different controller file that ends with .dll instead of .so (which is typically used on linux systems)

[HansiLeMann]

Thank you for your fast reply. I am running on Windows. The file libdiscon.so exist in the given location (https://github.com/IEAWindTask37/IEA-15-240-RWT/tree/master/OpenFAST/IEA-15-240-RWT/ServoData). In same location there is a libdiscon.dll. Do I need to specify somehow that I run on windows?

[jjonkman]

When simulating the OpenFAST model of the IEA Wind 15-MW reference wind turbine on Windows, you must change ServoDyn input DLL_FileName from "libdiscon.so" to "libdiscon.dll" (including path).

Best regards,

[HansiLeMann]

Thank you! It worked.