Hi NLR,
We are trying to model a 22MW idling turbine at 50m/s steady wind with fixed base in OpenFAST.
The Aerodyn and Servodyn files are attached.
We have not set GenDOF to False because we want to model idling turbine and not a braked one.
- However when looking at the results of the Rotor Thrust (RtAeroFxh) we see a very large moment (in the order of 45 MN-m) in the initial step. We have set the initial blade pitch to 90 in Elastodyn.
What could be leading to such high initial values ?
2. We observe a initial highly transient response in the tower base shears and moments, even though Aero forces responses are as expected for an Idling case.
Rotor Force is as expected
Aerodyn_parked file
```
------- AERODYN v15.03.* INPUT FILE ------------------------------------------------
Generated with AeroElasticSE FAST driver
====== General Options ============================================================================
False Echo - Echo the input to "<rootname>.AD.ech"? (flag)
Default DTAero - Time interval for aerodynamic calculations {or "default"} (s)
0 Wake_Mod - Wake/induction model (switch) {0=none, 1=BEMT, 3=OLAF} [Wake_Mod cannot be 2 or 3 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}
1 TwrShadow - Calculate tower influence on wind based on downstream tower shadow (switch) {0=none, 1=Powles model, 2=Eames model}
True TwrAero - Calculate tower aerodynamic loads? (flag)
False CavitCheck - Perform cavitation check? (flag) [UA_Mod must be 0 when CavitCheck=true]
False Buoyancy - Include buoyancy effects? (flag)
False NacelleDrag - Include Nacelle Drag effects? (flag)
False CompAA - Flag to compute AeroAcoustics calculation [used only when Wake_Mod = 1 or 2]
AeroAcousticsInput.dat AA_InputFile - AeroAcoustics input file [used only when CompAA=true]
====== Environmental Conditions ===================================================================
1.225 AirDens - Air density (kg/m^3)
1.4775510204081632e-05 KinVisc - Kinematic viscosity of working fluid (m^2/s)
340.0 SpdSound - Speed of sound in working fluid (m/s)
103500.0 Patm - Atmospheric pressure (Pa) [used only when CavitCheck=True]
1700.0 Pvap - Vapour pressure of working fluid (Pa) [used only when CavitCheck=True]
====== Blade-Element/Momentum Theory Options ====================================================== [unused when Wake_Mod=0 or 3, except for BEM_Mod]
2 BEM_Mod - BEM model {1=legacy NoSweepPitchTwist, 2=polar} (switch) [used for all Wake_Mod to determine output coordinate system]
--- Skew correction
0 Skew_Mod - Skew model {0=No skew model, -1=Remove non-normal component for linearization, 1=skew model active}
False SkewMomCorr - Turn the skew momentum correction on or off [used only when Skew_Mod=1]
default SkewRedistr_Mod - Type of skewed-wake correction model (switch) {0=no redistribution, 1=Glauert/Pitt/Peters, default=1} [used only when Skew_Mod=1]
1.4726215563702154 SkewRedistrFactor - Constant used in Pitt/Peters skewed wake model {or "default" is 15/32*pi} (-) [used only when Skew_Mod=1 and SkewRedistr_Mod=1]
--- BEM algorithm
True TipLoss - Use the Prandtl tip-loss model? (flag) [unused when Wake_Mod=0 or 3]
True HubLoss - Use the Prandtl hub-loss model? (flag) [unused when Wake_Mod=0 or 3]
True TanInd - Include tangential induction in BEMT calculations? (flag) [unused when Wake_Mod=0 or 3]
True AIDrag - Include the drag term in the axial-induction calculation? (flag) [unused when Wake_Mod=0 or 3]
True TIDrag - Include the drag term in the tangential-induction calculation? (flag) [unused when Wake_Mod=0,3 or TanInd=FALSE]
Default IndToler - Convergence tolerance for BEMT nonlinear solve residual equation {or "default"} (-) [unused when Wake_Mod=0 or 3]
500 MaxIter - Maximum number of iteration steps (-) [unused when Wake_Mod=0]
--- Shear correction
False SectAvg - Use sector averaging (flag)
1 SectAvgWeighting - Weighting function for sector average {1=Uniform, default=1} within a sector centered on the blade (switch) [used only when SectAvg=True]
default SectAvgNPoints - Number of points per sectors (-) {default=5} [used only when SectAvg=True]
default SectAvgPsiBwd - Backward azimuth relative to blade where the sector starts (<=0) {default=-60} (deg) [used only when SectAvg=True]
default SectAvgPsiFwd - Forward azimuth relative to blade where the sector ends (>=0) {default=60} (deg) [used only when SectAvg=True]
--- Dynamic wake/inflow
0 DBEMT_Mod - Type of dynamic BEMT (DBEMT) model {0=No Dynamic Wake, -1=Frozen Wake for linearization, 1:constant tau1, 2=time-dependent tau1, 3=constant tau1 with continuous formulation} (-)
34.079999999999984 tau1_const - Time constant for DBEMT (s) [used only when Wake_Mod=2 and DBEMT_Mod=1]
====== OLAF -- cOnvecting LAgrangian Filaments (Free Vortex Wake) Theory Options ================== [used only when Wake_Mod=3]
IEA-22-280-RWT_OLAF.dat OLAFInputFileName - Input file for OLAF [used only when Wake_Mod=3]
====== Unsteady Airfoil Aerodynamics Options ====================================================
True AoA34 - Sample the angle of attack (AoA) at the 3/4 chord or the AC point {default=True} [always used]
0 UA_Mod - Unsteady Aero Model Switch (switch) {0=Quasi-steady (no UA), 2=B-L Gonzalez, 3=B-L Minnema/Pierce, 4=B-L HGM 4-states, 5=B-L HGM+vortex 5 states, 6=Oye, 7=Boeing-Vertol}
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 UA_Mod>0]
3 IntegrationMethod - Switch to indicate which integration method UA uses (1=RK4, 2=AB4, 3=ABM4, 4=BDF2)
0.05 UAStartRad - Starting radius for dynamic stall (fraction of rotor radius [0.0,1.0]) [used only when UA_Mod>0; if line is missing UAStartRad=0]
1 UAEndRad - Ending radius for dynamic stall (fraction of rotor radius [0.0,1.0]) [used only when UA_Mod>0; if line is missing UAEndRad=1]
ServoDyn Parked file
------- SERVODYN v1.05.* INPUT FILE --------------------------------------------
Generated with AeroElasticSE FAST driver
---------------------- SIMULATION CONTROL --------------------------------------
False Echo - Echo input data to <RootName>.ech (flag)
default DT - Communication interval for controllers (s) (or "default")
---------------------- PITCH CONTROL -------------------------------------------
5 PCMode - Pitch control mode {0: none, 3: user-defined from routine PitchCntrl, 4: user-defined from Simulink/Labview, 5: user-defined from Bladed-style DLL} (switch)
0.0 TPCOn - Time to enable active pitch control (s) [unused when PCMode=0]
0.0 TPitManS(1) - Time to start override pitch maneuver for blade 1 and end standard pitch control (s)
0.0 TPitManS(2) - Time to start override pitch maneuver for blade 2 and end standard pitch control (s)
0.0 TPitManS(3) - Time to start override pitch maneuver for blade 3 and end standard pitch control (s) [unused for 2 blades]
1800.0 PitManRat(1) - Pitch rate at which override pitch maneuver heads toward final pitch angle for blade 1 (deg/s)
1800.0 PitManRat(2) - Pitch rate at which override pitch maneuver heads toward final pitch angle for blade 2 (deg/s)
1800.0 PitManRat(3) - Pitch rate at which override pitch maneuver heads toward final pitch angle for blade 3 (deg/s) [unused for 2 blades]
90.0 BlPitchF(1) - Blade 1 final pitch for pitch maneuvers (degrees)
90.0 BlPitchF(2) - Blade 2 final pitch for pitch maneuvers (degrees)
90.0 BlPitchF(3) - Blade 3 final pitch for pitch maneuvers (degrees) [unused for 2 blades]
---------------------- GENERATOR AND TORQUE CONTROL ----------------------------
5 VSContrl - Variable-speed control mode {0: none, 1: simple VS, 3: user-defined from routine UserVSCont, 4: user-defined from Simulink/Labview, 5: user-defined from Bladed-style DLL} (switch)
1 GenModel - Generator model {1: simple, 2: Thevenin, 3: user-defined from routine UserGen} (switch) [used only when VSContrl=0]
95.4 GenEff - Generator efficiency [ignored by the Thevenin and user-defined generator models] (%)
True GenTiStr - Method to start the generator {T: timed using TimGenOn, F: generator speed using SpdGenOn} (flag)
True GenTiStp - Method to stop the generator {T: timed using TimGenOf, F: when generator power = 0} (flag)
99999.0 SpdGenOn - Generator speed to turn on the generator for a startup (HSS speed) (rpm) [used only when GenTiStr=False]
0.0 TimGenOn - Time to turn on the generator for a startup (s) [used only when GenTiStr=True]
99999.0 TimGenOf - Time to turn off the generator (s) [used only when GenTiStp=True]
---------------------- SIMPLE VARIABLE-SPEED TORQUE CONTROL --------------------
7.061131867192265 VS_RtGnSp - Rated generator speed for simple variable-speed generator control (HSS side) (rpm) [used only when VSContrl=1]
31219733.35544 VS_RtTq - Rated generator torque/constant generator torque in Region 3 for simple variable-speed generator control (HSS side) (N-m) [used only when VSContrl=1]
626153.114868262 VS_Rgn2K - Generator torque constant in Region 2 for simple variable-speed generator control (HSS side) (N-m/rpm^2) [used only when VSContrl=1]
2.0 VS_SlPc - Rated generator slip percentage in Region 2 1/2 for simple variable-speed generator control (%) [used only when VSContrl=1]
---------------------- SIMPLE INDUCTION GENERATOR ------------------------------
99999.0 SIG_SlPc - Rated generator slip percentage (%) [used only when VSContrl=0 and GenModel=1]
99999.0 SIG_SySp - Synchronous (zero-torque) generator speed (rpm) [used only when VSContrl=0 and GenModel=1]
99999.0 SIG_RtTq - Rated torque (N-m) [used only when VSContrl=0 and GenModel=1]
99999.0 SIG_PORt - Pull-out ratio (Tpullout/Trated) (-) [used only when VSContrl=0 and GenModel=1]
---------------------- THEVENIN-EQUIVALENT INDUCTION GENERATOR -----------------
99999.0 TEC_Freq - Line frequency [50 or 60] (Hz) [used only when VSContrl=0 and GenModel=2]
0 TEC_NPol - Number of poles [even integer > 0] (-) [used only when VSContrl=0 and GenModel=2]
99999.0 TEC_SRes - Stator resistance (ohms) [used only when VSContrl=0 and GenModel=2]
99999.0 TEC_RRes - Rotor resistance (ohms) [used only when VSContrl=0 and GenModel=2]
99999.0 TEC_VLL - Line-to-line RMS voltage (volts) [used only when VSContrl=0 and GenModel=2]
99999.0 TEC_SLR - Stator leakage reactance (ohms) [used only when VSContrl=0 and GenModel=2]
99999.0 TEC_RLR - Rotor leakage reactance (ohms) [used only when VSContrl=0 and GenModel=2]
99999.0 TEC_MR - Magnetizing reactance (ohms) [used only when VSContrl=0 and GenModel=2]
---------------------- HIGH-SPEED SHAFT BRAKE ----------------------------------
0 HSSBrMode - HSS brake model {0: none, 1: simple, 3: user-defined from routine UserHSSBr, 4: user-defined from Simulink/Labview, 5: user-defined from Bladed-style DLL} (switch)
99999.0 THSSBrDp - Time to initiate deployment of the HSS brake (s)
99999.0 HSSBrDT - Time for HSS-brake to reach full deployment once initiated (sec) [used only when HSSBrMode=1]
99999.0 HSSBrTqF - Fully deployed HSS-brake torque (N-m)
---------------------- NACELLE-YAW CONTROL -------------------------------------
0 YCMode - Yaw control mode {0: none, 3: user-defined from routine UserYawCont, 4: user-defined from Simulink/Labview, 5: user-defined from Bladed-style DLL} (switch)
99999.0 TYCOn - Time to enable active yaw control (s) [unused when YCMode=0]
0.0 YawNeut - Neutral yaw position--yaw spring force is zero at this yaw (degrees)
9093012484.130638 YawSpr - Nacelle-yaw spring constant (N-m/rad)
6410654.157064741 YawDamp - Nacelle-yaw damping constant (N-m/(rad/s))
99999.0 TYawManS - Time to start override yaw maneuver and end standard yaw control (s)
0.25 YawManRat - Yaw maneuver rate (in absolute value) (deg/s)
0.0 NacYawF - Final yaw angle for override yaw maneuvers (degrees)
---------------------- AERODYNAMIC FLOW CONTROL --------------------------------
0 AfCmode - Airfoil control mode {0: none, 1: cosine wave cycle, 4: user-defined from Simulink/Labview, 5: user-defined from Bladed-style DLL} (switch)
0.0 AfC_Mean - Mean level for cosine cycling or steady value (-) [used only with AfCmode==1]
0.0 AfC_Amp - Amplitude for for cosine cycling of flap signal (-) [used only with AfCmode==1]
0.0 AfC_phase - Phase relative to the blade azimuth (0 is vertical) for for cosine cycling of flap signal (deg) [used only with AfCmode==1]
---------------------- STRUCTURAL CONTROL --------------------------------------
0 NumBStC - Number of blade structural controllers (integer)
"unused" BStCfiles - Name of the files for blade structural controllers (quoted strings) [unused when NumBStC==0]
0 NumNStC - Number of nacelle structural controllers (integer)
"unused" NStCfiles - Name of the files for nacelle structural controllers (quoted strings) [unused when NumNStC==0]
0 NumTStC - Number of tower structural controllers (integer)
"unused" TStCfiles - Name of the files for tower structural controllers (quoted strings) [unused when NumTStC==0]
0 NumSStC - Number of substructure structural controllers (integer)
"unused" SStCfiles - Name of the files for substructure structural controllers (quoted strings) [unused when NumSStC==0]
---------------------- CABLE CONTROL -------------------------------------------
0 CCmode - Cable control mode {0: none, 4: user-defined from Simulink/Labview, 5: user-defined from Bladed-style DLL} (switch)
---------------------- BLADED INTERFACE ---------------------------------------- [used only with Bladed Interface]
"../IEA-22-280-RWT/libdiscon.dll" DLL_FileName - Name/location of the dynamic library {.dll [Windows] or .so [Linux]} in the Bladed-DLL format (-) [used only with Bladed Interface]
"IEA-22-280-RWT_DISCON.IN" DLL_InFile - Name of input file sent to the DLL (-) [used only with Bladed Interface]
"DISCON" DLL_ProcName - Name of procedure in DLL to be called (-) [case sensitive; used only with DLL Interface]
default DLL_DT - Communication interval for dynamic library (s) (or "default") [used only with Bladed Interface]
False DLL_Ramp - Whether a linear ramp should be used between DLL_DT time steps [introduces time shift when true] (flag) [used only with Bladed Interface]
99999.0 BPCutoff - Cuttoff frequency for low-pass filter on blade pitch from DLL (Hz) [used only with Bladed Interface]
0.0 NacYaw_North - Reference yaw angle of the nacelle when the upwind end points due North (deg) [used only with Bladed Interface]
0 Ptch_Cntrl - Record 28: Use individual pitch control {0: collective pitch; 1: individual pitch control} (switch) [used only with Bladed Interface]
0.0 Ptch_SetPnt - Record 5: Below-rated pitch angle set-point (deg) [used only with Bladed Interface]
0.0 Ptch_Min - Record 6: Minimum pitch angle (deg) [used only with Bladed Interface]
0.0 Ptch_Max - Record 7: Maximum pitch angle (deg) [used only with Bladed Interface]
0.0 PtchRate_Min - Record 8: Minimum pitch rate (most negative value allowed) (deg/s) [used only with Bladed Interface]
0.0 PtchRate_Max - Record 9: Maximum pitch rate (deg/s) [used only with Bladed Interface]
0.0 Gain_OM - Record 16: Optimal mode gain (Nm/(rad/s)^2) [used only with Bladed Interface]
0.0 GenSpd_MinOM - Record 17: Minimum generator speed (rpm) [used only with Bladed Interface]
0.0 GenSpd_MaxOM - Record 18: Optimal mode maximum speed (rpm) [used only with Bladed Interface]
0.0 GenSpd_Dem - Record 19: Demanded generator speed above rated (rpm) [used only with Bladed Interface]
0.0 GenTrq_Dem - Record 22: Demanded generator torque above rated (Nm) [used only with Bladed Interface]
0.0 GenPwr_Dem - Record 13: Demanded power (W) [used only with Bladed Interface]
---------------------- BLADED INTERFACE TORQUE-SPEED LOOK-UP TABLE -------------
0 DLL_NumTrq - Record 26: No. of points in torque-speed look-up table {0 = none and use the optimal mode parameters; nonzero = ignore the optimal mode PARAMETERs by setting Record 16 to 0.0} (-) [used only with Bladed Interface]
GenSpd_TLU GenTrq_TLU
(rpm) (Nm)
---------------------- OUTPUT --------------------------------------------------
False SumPrint - Print summary data to <RootName>.sum (flag) (currently unused)
1 OutFile - Switch to determine where output will be placed: {1: in module output file only; 2: in glue code output file only; 3: both} (currently unused)
True TabDelim - Use tab delimiters in text tabular output file? (flag) (currently unused)
"ES10.3E2" OutFmt - Format used for text tabular output (except time). Resulting field should be 10 characters. (quoted string) (currently unused)
0.0 TStart - Time to begin tabular output (s) (currently unused)
OutList - The next line(s) contains a list of output parameters. See OutListParameters.xlsx for a listing of available output channels, (-)
"GenPwr"
"GenTq"
END of input file (the word "END" must appear in the first 3 columns of this last OutList line)
---------------------------------------------------------------------------------------
Thank you,
Ashok
