Dear @Jason.Jonkman,
Thank you for your response. For your better understanding of my issue, here I attach the files of one simulation where the blades are set to assess free decay behavior. I changed NumCrctn to 5 this time, I also tried other values but unfortunately OpenFAST keeps crashing if I enable both BeamDyn and the structural controller. When I use this configuration and enable ElastoDyn instead however, I obtain reasonable blade responses, as observed in the next figure.
------- ELASTODYN v1.03.* INPUT FILE -------------------------------------------
IEA 15 MW offshore reference model monopile configuration
---------------------- SIMULATION CONTROL --------------------------------------
False Echo - Echo input data to "<RootName>.ech" (flag)
3 Method - Integration method: {1: RK4, 2: AB4, or 3: ABM4} (-)
"default" DT Integration time step (s)
---------------------- DEGREES OF FREEDOM --------------------------------------
True FlapDOF1 - First flapwise blade mode DOF (flag)
True FlapDOF2 - Second flapwise blade mode DOF (flag)
True EdgeDOF - First edgewise blade mode DOF (flag)
False TeetDOF - Rotor-teeter DOF (flag) [unused for 3 blades]
False DrTrDOF - Drivetrain rotational-flexibility DOF (flag)
False GenDOF - Generator DOF (flag)
False YawDOF - Yaw DOF (flag)
False TwFADOF1 - First fore-aft tower bending-mode DOF (flag)
False TwFADOF2 - Second fore-aft tower bending-mode DOF (flag)
False TwSSDOF1 - First side-to-side tower bending-mode DOF (flag)
False TwSSDOF2 - Second side-to-side tower bending-mode DOF (flag)
False PtfmSgDOF - Platform horizontal surge translation DOF (flag)
False PtfmSwDOF - Platform horizontal sway translation DOF (flag)
False PtfmHvDOF - Platform vertical heave translation DOF (flag)
False PtfmRDOF - Platform roll tilt rotation DOF (flag)
False PtfmPDOF - Platform pitch tilt rotation DOF (flag)
False PtfmYDOF - Platform yaw rotation DOF (flag)
---------------------- INITIAL CONDITIONS --------------------------------------
0.0 OoPDefl - Initial out-of-plane blade-tip displacement (meters)
0 IPDefl - Initial in-plane blade-tip deflection (meters)
0 BlPitch(1) - Blade 1 initial pitch (degrees)
0 BlPitch(2) - Blade 2 initial pitch (degrees)
0 BlPitch(3) - Blade 3 initial pitch (degrees) [unused for 2 blades]
0.0 TeetDefl - Initial or fixed teeter angle (degrees) [unused for 3 blades]
0.0 Azimuth - Initial azimuth angle for blade 1 (degrees)
0 RotSpeed - Initial or fixed rotor speed (rpm)
0.0 NacYaw - Initial or fixed nacelle-yaw angle (degrees)
0.0 TTDspFA - Initial fore-aft tower-top displacement (meters)
0.0 TTDspSS - Initial side-to-side tower-top displacement (meters)
0.0 PtfmSurge - Initial or fixed horizontal surge translational displacement of platform (meters)
0.0 PtfmSway - Initial or fixed horizontal sway translational displacement of platform (meters)
0.0 PtfmHeave - Initial or fixed vertical heave translational displacement of platform (meters)
0.0 PtfmRoll - Initial or fixed roll tilt rotational displacement of platform (degrees)
0.0 PtfmPitch - Initial or fixed pitch tilt rotational displacement of platform (degrees)
0.0 PtfmYaw - Initial or fixed yaw rotational displacement of platform (degrees)
---------------------- TURBINE CONFIGURATION -----------------------------------
3 NumBl - Number of blades (-)
120.97 TipRad - The distance from the rotor apex to the blade tip (meters)
3.97 HubRad - The distance from the rotor apex to the blade root (meters)
-4.0 PreCone(1) - Blade 1 cone angle (degrees)
-4.0 PreCone(2) - Blade 2 cone angle (degrees)
-4.0 PreCone(3) - Blade 3 cone angle (degrees) [unused for 2 blades]
0.0 HubCM - Distance from rotor apex to hub mass [positive downwind] (meters)
0.0 UndSling - Undersling length [distance from teeter pin to the rotor apex] (meters) [unused for 3 blades]
0.0 Delta3 - Delta-3 angle for teetering rotors (degrees) [unused for 3 blades]
0.0 AzimB1Up - Azimuth value to use for I/O when blade 1 points up (degrees)
-12.097571763912535 OverHang - Distance from yaw axis to rotor apex [3 blades] or teeter pin [2 blades] (meters)
0.0 ShftGagL - Distance from rotor apex [3 blades] or teeter pin [2 blades] to shaft strain gages [positive for upwind rotors] (meters)
0 ShftTilt - Rotor shaft tilt angle (degrees)
-5.125 NacCMxn - Downwind distance from the tower-top to the nacelle CM (meters)
0.0 NacCMyn - Lateral distance from the tower-top to the nacelle CM (meters)
4.315 NacCMzn - Vertical distance from the tower-top to the nacelle CM (meters)
0.0 NcIMUxn - Downwind distance from the tower-top to the nacelle IMU (meters)
0.0 NcIMUyn - Lateral distance from the tower-top to the nacelle IMU (meters)
0.0 NcIMUzn - Vertical distance from the tower-top to the nacelle IMU (meters)
4.349459414248071 Twr2Shft - Vertical distance from the tower-top to the rotor shaft (meters)
144.386 TowerHt - Height of tower above ground level [onshore] or MSL [offshore] (meters)
15. TowerBsHt - Height of tower base above ground level [onshore] or MSL [offshore] (meters)
0.0 PtfmCMxt - Downwind distance from the ground level [onshore] or MSL [offshore] to the platform CM (meters)
0.0 PtfmCMyt - Lateral distance from the ground level [onshore] or MSL [offshore] to the platform CM (meters)
15. PtfmCMzt - Vertical distance from the ground level [onshore] or MSL [offshore] to the platform CM (meters)
15. PtfmRefzt - Vertical distance from the ground level [onshore] or MSL [offshore] to the platform reference point (meters)
---------------------- MASS AND INERTIA ----------------------------------------
0.0 TipMass(1) - Tip-brake mass, blade 1 (kg)
0.0 TipMass(2) - Tip-brake mass, blade 2 (kg)
0.0 TipMass(3) - Tip-brake mass, blade 3 (kg) [unused for 2 blades]
69131 HubMass - Hub mass (kg)
969952 HubIner - Hub inertia about rotor axis [3 blades] or teeter axis [2 blades] (kg m^2)
1836784 GenIner - Generator inertia about HSS (kg m^2)
644857 NacMass - Nacelle mass (kg)
32929058 NacYIner - Nacelle inertia about yaw axis (kg m^2)
28249 YawBrMass - Yaw bearing mass (kg)
0.0 PtfmMass - Platform mass (kg)
0.0 PtfmRIner - Platform inertia for roll tilt rotation about the platform CM (kg m^2)
0.0 PtfmPIner - Platform inertia for pitch tilt rotation about the platform CM (kg m^2)
100000000.0 PtfmYIner - Platform inertia for yaw rotation about the platform CM (kg m^2)
---------------------- BLADE ---------------------------------------------------
50 BldNodes - Number of blade nodes (per blade) used for analysis (-)
"../IEA-15-240-RWT/IEA-15-240-RWT_ElastoDyn_blade.dat" BldFile1 - Name of file containing properties for blade 1 (quoted string)
"../IEA-15-240-RWT/IEA-15-240-RWT_ElastoDyn_blade.dat" BldFile2 - Name of file containing properties for blade 2 (quoted string)
"../IEA-15-240-RWT/IEA-15-240-RWT_ElastoDyn_blade.dat" BldFile3 - Name of file containing properties for blade 3 (quoted string) [unused for 2 blades]
---------------------- ROTOR-TEETER --------------------------------------------
0 TeetMod - Rotor-teeter spring/damper model {0: none, 1: standard, 2: user-defined from routine UserTeet} (switch) [unused for 3 blades]
0.0 TeetDmpP - Rotor-teeter damper position (degrees) [used only for 2 blades and when TeetMod=1]
0.0 TeetDmp - Rotor-teeter damping constant (N-m/(rad/s)) [used only for 2 blades and when TeetMod=1]
0.0 TeetCDmp - Rotor-teeter rate-independent Coulomb-damping moment (N-m) [used only for 2 blades and when TeetMod=1]
0.0 TeetSStP - Rotor-teeter soft-stop position (degrees) [used only for 2 blades and when TeetMod=1]
0.0 TeetHStP - Rotor-teeter hard-stop position (degrees) [used only for 2 blades and when TeetMod=1]
0.0 TeetSSSp - Rotor-teeter soft-stop linear-spring constant (N-m/rad) [used only for 2 blades and when TeetMod=1]
0.0 TeetHSSp - Rotor-teeter hard-stop linear-spring constant (N-m/rad) [used only for 2 blades and when TeetMod=1]
---------------------- DRIVETRAIN ----------------------------------------------
100.0 GBoxEff - Gearbox efficiency (%)
1.0 GBRatio - Gearbox ratio (-)
69737644900.0 DTTorSpr - Drivetrain torsional spring (N-m/rad)
49418406.0 DTTorDmp - Drivetrain torsional damper (N-m/(rad/s))
---------------------- FURLING -------------------------------------------------
False Furling - Read in additional model properties for furling turbine (flag) [must currently be FALSE)
"unused" FurlFile - Name of file containing furling properties (quoted string) [unused when Furling=False]
---------------------- TOWER ---------------------------------------------------
20 TwrNodes - Number of tower nodes used for analysis (-)
"../IEA-15-240-RWT-Monopile/IEA-15-240-RWT-Monopile_ElastoDyn_tower.dat" TwrFile - Name of file containing tower properties (quoted string)
---------------------- OUTPUT --------------------------------------------------
True SumPrint - Print summary data to "<RootName>.sum" (flag)
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)
1 DecFact - Decimation factor for tabular output {1: output every time step} (-) (currently unused)
1 NTwGages - Number of tower nodes that have strain gages for output [0 to 9] (-)
20 TwrGagNd - List of tower nodes that have strain gages [1 to TwrNodes] (-) [unused if NTwGages=0] TwrGagNd - List of tower nodes that have strain gages [1 to TwrNodes] (-) [unused if NTwGages=0] TwrGagNd - List of tower nodes that have strain gages [1 to TwrNodes] (-) [unused if NTwGages=0]
3 NBlGages - Number of blade nodes that have strain gages for output [0 to 9] (-)
5, 9, 13 BldGagNd - List of blade nodes that have strain gages [1 to BldNodes] (-) [unused if NBlGages=0] BldGagNd - List of blade nodes that have strain gages [1 to BldNodes] (-) [unused if NBlGages=0] BldGagNd - List of blade nodes that have strain gages [1 to BldNodes] (-) [unused if NBlGages=0]
OutList - The next line(s) contains a list of output parameters. See OutListParameters.xlsx for a listing of available output channels, (-)
"Azimuth"
"BldPitch1"
"BldPitch2"
"BldPitch3"
"GenSpeed"
"IPDefl1"
"NacYaw"
"OoPDefl1"
"RotSpeed"
"RotThrust"
"RotTorq"
"TTDspTwst"
"TipDxb1"
"TipDyb1"
"TipDxb2"
"TipDyb2"
"TipDxb3"
"TipDyb3"
---------------------------------------------------------------------------------------
------- SERVODYN v1.05.* INPUT FILE --------------------------------------------
IEA 15 MW offshore reference model monopile configuration
---------------------- SIMULATION CONTROL --------------------------------------
False Echo - Echo input data to <RootName>.ech (flag)
"default" DT - Communication interval for controllers (s) (or "default")
---------------------- PITCH CONTROL -------------------------------------------
0 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]
9999.9 TPitManS(1) - Time to start override pitch maneuver for blade 1 and end standard pitch control (s)
9999.9 TPitManS(2) - Time to start override pitch maneuver for blade 2 and end standard pitch control (s)
9999.9 TPitManS(3) - Time to start override pitch maneuver for blade 3 and end standard pitch control (s) [unused for 2 blades]
2.0 PitManRat(1) - Pitch rate at which override pitch maneuver heads toward final pitch angle for blade 1 (deg/s)
2.0 PitManRat(2) - Pitch rate at which override pitch maneuver heads toward final pitch angle for blade 2 (deg/s)
2.0 PitManRat(3) - Pitch rate at which override pitch maneuver heads toward final pitch angle for blade 3 (deg/s) [unused for 2 blades]
0.0 BlPitchF(1) - Blade 1 final pitch for pitch maneuvers (degrees)
0.0 BlPitchF(2) - Blade 2 final pitch for pitch maneuvers (degrees)
0.0 BlPitchF(3) - Blade 3 final pitch for pitch maneuvers (degrees) [unused for 2 blades]
---------------------- GENERATOR AND TORQUE CONTROL ----------------------------
0 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]
95.756 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)
9999.9 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]
9999.9 TimGenOf - Time to turn off the generator (s) [used only when GenTiStp=True]
---------------------- SIMPLE VARIABLE-SPEED TORQUE CONTROL --------------------
7.559987120819503 VS_RtGnSp - Rated generator speed for simple variable-speed generator control (HSS side) (rpm) [used only when VSContrl=1]
19624046.66639 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]
343357.4355671095 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. 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 ------------------------------
9999.9 SIG_SlPc - Rated generator slip percentage (%) [used only when VSContrl=0 and GenModel=1]
9999.9 SIG_SySp - Synchronous (zero-torque) generator speed (rpm) [used only when VSContrl=0 and GenModel=1]
9999.9 SIG_RtTq - Rated torque (N-m) [used only when VSContrl=0 and GenModel=1]
9999.9 SIG_PORt - Pull-out ratio (Tpullout/Trated) (-) [used only when VSContrl=0 and GenModel=1]
---------------------- THEVENIN-EQUIVALENT INDUCTION GENERATOR -----------------
9999.9 TEC_Freq - Line frequency [50 or 60] (Hz) [used only when VSContrl=0 and GenModel=2]
100 TEC_NPol - Number of poles [even integer > 0] (-) [used only when VSContrl=0 and GenModel=2]
9999.9 TEC_SRes - Stator resistance (ohms) [used only when VSContrl=0 and GenModel=2]
9999.9 TEC_RRes - Rotor resistance (ohms) [used only when VSContrl=0 and GenModel=2]
9999.9 TEC_VLL - Line-to-line RMS voltage (volts) [used only when VSContrl=0 and GenModel=2]
9999.9 TEC_SLR - Stator leakage reactance (ohms) [used only when VSContrl=0 and GenModel=2]
9999.9 TEC_RLR - Rotor leakage reactance (ohms) [used only when VSContrl=0 and GenModel=2]
9999.9 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)
0 THSSBrDp - Time to initiate deployment of the HSS brake (s)
9999.9 HSSBrDT - Time for HSS-brake to reach full deployment once initiated (sec) [used only when HSSBrMode=1]
28116.2 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)
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)
8458453511.0 YawSpr - Nacelle-yaw spring constant (N-m/rad)
28561762.0 YawDamp - Nacelle-yaw damping constant (N-m/(rad/s))
9999.9 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}
0.0 AfC_Mean - Mean level for sinusoidal cycling or steady value (-) [used only with AfCmode==1]
0.0 AfC_Amp - Amplitude for for cosine cycling of flap signal (AfC = AfC_Amp*cos(Azimuth+phase)+AfC_mean) (-) [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 ---------------------------------------
1 NumBStC - Number of blade structural controllers (integer)
"FDT_wTMD_15MW_98_mLoc_0.03_massRatio_StC15MW.dat" BStCfiles - Name of the file for blade tuned mass damper (quoted string) [unused when CompNTMD is false]
0 NumNStC - Number of nacelle structural controllers (integer)
"unused" NStCfiles - Name of the file for nacelle tuned mass damper (quoted string) [unused when CompNTMD is false]
0 NumTStC - Number of tower structural controllers (integer)
"unused" TStCfiles - Name of the file for tower tuned mass damper (quoted string) [unused when CompNTMD is false]
0 NumSStC - Number of sbustructure structural controllers (integer)
"unused" SStCfiles - Name of the file for sbustructure tuned mass damper (quoted string) [unused when CompNTMD is false]
---------------------- CABLE CONTROL ----------------------------------------
0 CCmode - Cable control mode {0- none, 4- user-defined from Simulink/Labview, 5- user-defineAfC_phased from Bladed-style DLL}
---------------------- BLADED INTERFACE ---------------------------------------- [used only with Bladed Interface]
"../IEA-15-240-RWT/ServoData/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-15-240-RWT-Monopile_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]
9999.9 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 --------------------------------------------------
True 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"
"BStC1_B1_XQ"
"BStC1_B1_YQ"
"BStC1_B2_XQ"
"BStC1_B2_YQ"
"BStC1_B3_XQ"
"BStC1_B3_YQ"
END of input file (the word "END" must appear in the first 3 columns of this last OutList line)
---------------------------------------------------------------------------------------
------- STRUCTURAL CONTROL (StC) INPUT FILE ----------------------------
Input file for tuned mass damper, module by Matt Lackner, Meghan Glade, and Semyung Park (UMass)
---------------------- SIMULATION CONTROL --------------------------------------
True Echo - Echo input data to <RootName>.ech (flag)
---------------------- StC DEGREES OF FREEDOM ----------------------------------
1 StC_DOF_MODE - DOF mode (switch) {0: No StC or TLCD DOF; 1: StC_X_DOF, StC_Y_DOF, and/or StC_Z_DOF (three independent StC DOFs); 2: StC_XY_DOF (Omni-Directional StC); 3: TLCD; 4: Prescribed force/moment time series; 5: Force determined by external DLL}
false StC_X_DOF - DOF on or off for StC X (flag) [Used only when StC_DOF_MODE=1]
true StC_Y_DOF - DOF on or off for StC Y (flag) [Used only when StC_DOF_MODE=1]
false StC_Z_DOF - DOF on or off for StC Z (flag) [Used only when StC_DOF_MODE=1]
---------------------- StC LOCATION ------------------------------------------- [relative to the reference origin of component attached to]
0 StC_P_X - At rest X position of StC (m)
0 StC_P_Y - At rest Y position of StC (m)
98 StC_P_Z - At rest Z position of StC (m)
---------------------- StC INITIAL CONDITIONS --------------------------------- [used only when StC_DOF_MODE=1 or 2]
0 StC_X_DSP - StC X initial displacement (m) [relative to at rest position]
0 StC_Y_DSP - StC Y initial displacement (m) [relative to at rest position]
0 StC_Z_DSP - StC Z initial displacement (m) [relative to at rest position; used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
"gravity" StC_Z_PreLd - StC Z pre-load (N) {"gravity" to offset for gravity load; "none" or 0 to turn off} [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
---------------------- StC CONFIGURATION -------------------------------------- [used only when StC_DOF_MODE=1 or 2]
0 StC_X_PSP - Positive stop position (maximum X mass displacement) (m)
0 StC_X_NSP - Negative stop position (minimum X mass displacement) (m)
0 StC_Y_PSP - Positive stop position (maximum Y mass displacement) (m)
0 StC_Y_NSP - Negative stop position (minimum Y mass displacement) (m)
0 StC_Z_PSP - Positive stop position (maximum Z mass displacement) (m) [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
0 StC_Z_NSP - Negative stop position (minimum Z mass displacement) (m) [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
---------------------- StC MASS, STIFFNESS, & DAMPING ------------------------- [used only when StC_DOF_MODE=1 or 2]
0 StC_X_M - StC X mass (kg) [must equal StC_Y_M for StC_DOF_MODE = 2]
75 StC_Y_M - StC Y mass (kg) [must equal StC_X_M for StC_DOF_MODE = 2]
0 StC_Z_M - StC Z mass (kg) [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
0 StC_XY_M - StC XY mass (kg) [used only when StC_DOF_MODE=2]
0 StC_X_K - StC X stiffness (N/m)
1534.3398 StC_Y_K - StC Y stiffness (N/m)
0 StC_Z_K - StC Z stiffness (N/m) [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
0 StC_X_C - StC X damping (N/(m/s))
56.5307 StC_Y_C - StC Y damping (N/(m/s))
0 StC_Z_C - StC Z damping (N/(m/s)) [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
0 StC_X_KS - Stop spring X stiffness (N/m)
0 StC_Y_KS - Stop spring Y stiffness (N/m)
0 StC_Z_KS - Stop spring Z stiffness (N/m) [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
0 StC_X_CS - Stop spring X damping (N/(m/s))
0 StC_Y_CS - Stop spring Y damping (N/(m/s))
0 StC_Z_CS - Stop spring Z damping (N/(m/s)) [used only when StC_DOF_MODE=1 and StC_Z_DOF=TRUE]
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Note that no major changes were made in the DISCON.IN file, compared to the one provided on the repository (https://github.com/IEAWindSystems/IEA-15-240-RWT/blob/master/OpenFAST/IEA-15-240-RWT-Monopile/IEA-15-240-RWT-Monopile_DISCON.IN)
Now, if I only change NumBStC to 0 (no structural control), OpenFAST runs normally and the response of the blade with BeamDyn is:
The discrepancy here is that I do get free decay oscillation response from the blades with ElastoDyn (observe first image), but BeamDyn gives me a flat number (for all 3 blades) or no free decay response as I see it (second image for blade 3). That is why I tried changing the initial in-plane deflection but now I understand, thanks to your explanation, that it is not an input used by BeamDyn. Does this mean the blades are not affected by gravity when BeamDyn is used, as opposed to ElastoDyn?
I greatly appreciate your input on this matter.
Best,
Fanny
