Aerodyn version with motion of the platform

Good morning,
I am trying to use a modified version of Aerodyn that simulates a motion of the platform, the one available here on this branch :
github.com/ebranlard/openfast/tree/f/driver
I am trying to simulate an oscillating surge motion in the wind direction, but the PtfmSurge remains zero instead of being sinusoidal. I don’t know what is wrong in my driver file (here attached)
If you have please any advice or clue ?
Many thanks in advance.
Best regards.
Florence Haudin.

Dear Florence,

I don’t see that your input file was actually attached.

Best regards,

Hi Jason,
Thanks for your reply.
I am getting a http error trying to load the file. I thought it was nevertheless attached. So I am copying the content of the file here. Something may be wrong inside it but I don’t see what.
Many thanks for any help.
Best regards.
Florence Haudin.

----- AeroDyn Driver Input File -------------------------------------------------
BAR turbine driver input file, using advanced input, sinusoidal base motion
----- Input Configuration -------------------------------------------------------
True Echo - Echo input parameters to “.ech”?
1 AnalysisType - {1: multiple turbines, one simulation, 2: one turbine, one time-dependent simulation, 3: one turbine, combined cases}
400 TMax - Total run time [used only when AnalysisType/=3] (s)
0.025 DT - Simulation time step [used only when AnalysisType/=3] (s)
“FAST_run3.AD.dat” AeroFile - Name of the primary AeroDyn input file
----- Inflow Data ---------------------------------------------------------------
0 CompInflow - Compute inflow wind velocities (switch) {0=Steady Wind; 1=InflowWind}
“unused” InflowFile - Name of the InflowWind input file [used only when CompInflow=1]
4.19 HWindSpeed - Horizontal wind speed [used only when CompInflow=0 and AnalysisType/=3] (m/s)
2.0 RefHt - Reference height for horizontal wind speed [used only when CompInflow=0 and AnalysisType/=3] (m)
0 PLExp - Power law exponent [used only when CompInflow=0 and AnalysisType/=3] (-)
----- Turbine Data --------------------------------------------------------------
1 NumTurbines - Number of turbines
----- Turbine(1) ----------------------------------------------------------------
False BasicHAWTFormat(1) - Flag to switch between basic or generic input format {True: next 7 lines are basic inputs, False: Base/Twr/Nac/Hub/Bld geometry and motion must follow}
0,0,0 BaseOriginInit(1) - x,y,z coordinates of base origin (m)
0,0,0 BaseOrientationInit(1) - successive rotations (theta_x, theta_y, theta_z) defining initial orientation of the base frame from the global frame (e.g. roll, tilt, yaw) (deg)
True HasTower(1) - True if turbine has a tower (flag)
True HAWTprojection(1) - True if turbine is a horizontal axis turbine (for AeroDyn projections) (flag)
0,0,0 TwrOrigin_t(1) - Coordinate of tower base in base coordinates [used only when HasTower is True] (m)
0,0,1.59959 NacOrigin_t(1) - x,y,z coordinates of nacelle origin (and tower top) from base, in base coordinates (m)
-0.09467,0,0.049492 HubOrigin_n(1) - NOTE: Bar has 7m overhang, tilt of 6deg, and twr2shaft 3.09343 x,y,z coordinates of hub origin from nacelle origin, in nacelle coordinates (m)
0,5,0 HubOrientation_n(1) - successive rotations (theta_x, theta_y, theta_z) defining initial orientation of the hub frame from the nacelle frame (e.g. roll, tilt, yaw). The x axis needs to be aligned with the rotational speed. (deg)
----- Turbine(1) Blades -----------------------------------------------------------------
3 NumBlades(1) - Number of blades for current rotor (-)
0,0,0 BldOrigin_h(1_1) - Orign of blade 1 wrt. hub origin in hub coordinates (m)
0,0,0 BldOrigin_h(1_2) - Orign of blade 1 wrt. hub origin in hub coordinates (m)
0,0,0 BldOrigin_h(1_3) - Orign of blade 1 wrt. hub origin in hub coordinates (m)
0 ,0,0 BldOrientation_h(1_1) - successive rotations (theta_x, theta_y, theta_z) defining initial orientation of the blade frame from the hub frame such that the “z” is along span, “y” along trailing edge without pitch (azimuth, precone, pitch) (deg)
120,0,0 BldOrientation_h(1_2) - successive rotations (theta_x, theta_y, theta_z) defining initial orientation of the blade frame from the hub frame such that the “z” is along span, “y” along trailing edge without pitch (azimuth, precone, pitch) (deg)
240,0,0 BldOrientation_h(1_3) - successive rotations (theta_x, theta_y, theta_z) defining initial orientation of the blade frame from the hub frame such that the “z” is along span, “y” along trailing edge without pitch (azimuth, precone, pitch) (deg)
0.089 BldHubRad_bl(1_1) - z-offset in blade coordinates of blade 1 where radial input data start (m)
0.089 BldHubRad_bl(1_2) - z-offset in blade coordinates of blade 2 where radial input data start (m)
0.089 BldHubRad_bl(1_3) - z-offset in blade coordinates of blade 3 where radial input data start (m)
----- Turbine(1) Base Motion [used only when AnalysisType=1] --------------------
1 BaseMotionType(1) - Type of motion prescribed for this base {0: fixed, 1: Sinusoidal motion, 2: arbitrary motion} (flag)
1 DegreeOfFreedom(1) - {1:xt, 2:yt, 3:zt, 4:theta_xt, 5:theta_yt, 6:theta_zt} [used only when BaseMotionType=1] (flag)
-0.125 Amplitude(1) - Amplitude of sinusoidal motion [used only when BaseMotionType=1]
0.125 Frequency(1) - Frequency of sinusoidal motion [used only when BaseMotionType=1]
“unused” BaseMotionFileName(1) - Filename containing arbitrary base motion (19 columns: Time, x, y, z, theta_x, …, alpha_z) [used only when BaseMotionType=2]
0 NacMotionType(1) - Type of motion prescribed for the nacelle {0: fixed yaw, 1: time varying yaw angle} (flag)
0 NacYaw(1) - Yaw angle (about z_t) of the nacelle [user only when NacMotionType=0] (deg)
“unused” NacMotionFileName(1) - Filename containing yaw motion [used only when NacMotionType=1]
0 RotMotionType(1) - Type of motion prescribed for this rotor {0: constant rotation, 1: time varying rotation} (flag)
240 RotSpeed(1) - Rotational speed of rotor in rotor coordinates [used only when RotorMotionType=0] (rpm)
“unused” RotMotionFileName(1) - Filename containing rotor motion [used only when RotorMotionType=1]
0 BldMotionType(1) - Type of pitch motion prescribed for the blades {0: fixed, 1: time varying pitch} (flag)
0 BldPitch(1_1) - Blade 1 pitch [used only when BlMotiontype=1] (deg)
0 BldPitch(1_2) - Blade 2 pitch [used only when BlMotiontype=1] (deg)
0 BldPitch(1_3) - Blade 3 pitch [used only when BlMotiontype=1] (deg)
“unused” BldMotionFileName(1_1) - Filename containing blade pitch motion [used only when BlMotionType=1]
“unused” BldMotionFileName(1_2) - Filename containing blade pitch motion [used only when BlMotionType=1]
“unused” BldMotionFileName(1_3) - Filename containing blade pitch motion [used only when BlMotionType=1]
----- Time-dependent Analysis [used only when AnalysisType=2] -------------------
“unused” TimeAnalysisFileName - Filename containing time series (6 column: Time, WndSpeed, ShearExp, RotSpd, Pitch, Yaw).
----- Combined-Case Analysis [used only when AnalysisType=3] -------------------
0 NumCases - Number of cases to run
WndSpeed ShearExp RotSpd Pitch Yaw dT Tmax DOF Amplitude Frequency
(m/s) (-) (rpm) (deg) (deg) (s) (s) (-) (-) (Hz)
----- I/O Settings --------------------------------------------------------------
“ES15.8E2” OutFmt - Format used for text tabular output, excluding the time channel. Resulting field should be 10 characters. (quoted string)
3 OutFileFmt - Format for tabular (time-marching) output file (switch) {1: text file [.out], 2: binary file [.outb], 3: both}
1 WrVTK - VTK visualization data output: (switch) {0=none; 1=animation}
2 VTKHubRad - HubRadius for VTK visualization (m)
-7,-4,0,21,8,8 VTKNacDim - Nacelle Dimension for VTK visualization x0,y0,z0,Lx,Ly,Lz (m)

Dear Florence,

I haven’t reviewed your input file in great detail, but can you clarify what error you are getting? If AeroDyn is complaining that it can’t read the input data properly, e.g., due to improper file formatting, have you tried enabling the Echo option to debug?

Best regards,

Hi again Jason,
In fact the simulation runs correctly and goes to the end. I guess the message(in the screen shot) is normal when no tower is defined (tower shadow =0) ?
The .out file with results is generated but if the plateform surge is null.
I am sending you the .ech and .out (for a 4s simulation).
Concerning the aerodyn input file, I have been able to run simulations with proper results in the case of a constant wind and no surge displacement of the platform so I guess that things are ok from this side.
Many thanks for your help.
Best regards
Florence Haudin.
FAST_run3_AD_out.txt (86.8 KB)
FAST_run3_AD_ech.txt (4.93 KB)

Hi Florence,

I opened your out file in pyDatView (https://github.com/ebranlard/pyDatView, which I would recommend for simple visualizations), and the PtfmSurge seems to have the right amplitude and frequency (see image enclosed). Could it be that your postprocessing script has an issue?

I’ve also used your driver file together with the AeroDyn files from OC6 from Roger (I’m guessing you are running this turbine too?), and didn’t see any problem.

If you still have issues, please send us the full model (driver + aerodyn + polar, trying to simplifying it to one polar maybe), I can have a look at it.

You can also try to clone and compile the latest version of the driver. Some of the info message have been removed, and maybe some small bugs.

Cheers,

Emmanuel

Hi Emmanuel,
Thanks for your reply. The problem was a post-processing bug.
Nevertheless, I think that my results for thrust and torque are a bit under-evaluated and I don’t know why.
Best regards.
Florence Haudin.
Ps : I don’t see how I could simplify the polars into 1 only

Florence, I dont find the attached file