Sir,

I was trying to conduct a linearization analysis to get natural frequencies for platform model 2(i.e, Fixed bottom offshore) coupled spring model in seismic. But while performing analysis I was getting an error message like an error occurred while trying to read CurrMod. This was the echo file I got and from the Current section, echo file was not reading. I Can’t figure out what’s wrong and another doubt was which Matlab scripts should I use to process the linearization output files. Can I use the old Matlab scripts mentioned in the Matlab toolbox for Openfast to this model? Can someone help me through these doubts?

This file of echoed input was generated by FAST (v7.02.00d-bjj, 20-Feb-2013) on 21-Jun-2020 at 23:29:23.

Turbine input data from file “E:\Seismic\linear\NRELOffshrBsline5MW_Onshore.fst”:

NREL 5.0 MW Baseline Wind Turbine for Use in Offshore Analysis.

---------------------- SIMULATION CONTROL --------------------------------------

T Echo - Echo input to “echo.out”

1 ADAMSPrep - ADAMS preprocessor mode

2 AnalMode - Analysis mode

3 NumBl - Number of blades

6.3000E+02 TMax - Total run time

5.0000E-03 DT - Integration time step

---------------------- TURBINE CONTROL -----------------------------------------

0 YCMode - Yaw control mode

9.9999E+03 TYCOn - Time to enable yaw control

0 PCMode - Pitch control mode

0.0000E+00 TPCOn - Time to enable pitch control

2 VSContrl - Variable-speed-generator control switch

9.9999E+03 VS_RtGnSp - Rated generator speed for simple variable-speed generator control

9.9999E+03 VS_RtTq - Rated generator torque/constant generator torque in Region 3 for simple variable-speed generator control

9.9999E+03 VS_Rgn2K - Generator torque constant in Region 2 for simple variable-speed generator control

9.9999E+03 VS_SlPc - Rated generator slip percentage in Region 2 1/2 for simple variable-speed generator control

2 GenModel - Generator model

T GenTiStr - Start generator based upon T: time or F: generator speed

T GenTiStp - Stop generator based upon T: time or F: generator power = 0

9.9999E+03 SpdGenOn - Generator speed to turn on the generator

0.0000E+00 TimGenOn - Time to turn on generator

9.9999E+03 TimGenOf - Time to turn off generator

1 HSSBrMode - HSS brake model

9.9999E+03 THSSBrDp - Time to initiate deployment of the HSS brake

9999.9 TiDynBrk - Time to initiate deployment of the dynamic generator brake [CURRENTLY IGNORED] (s)

9.9999E+03 TTpBrDp(1) - Time to initiate deployment of tip brakes

9.9999E+03 TTpBrDp(2) - Time to initiate deployment of tip brakes

9.9999E+03 TTpBrDp(3) - Time to initiate deployment of tip brakes

9.9999E+03 TBDepISp(1) - Deployment-initiation speed for the tip brakes

9.9999E+03 TBDepISp(2) - Deployment-initiation speed for the tip brakes

9.9999E+03 TBDepISp(3) - Deployment-initiation speed for the tip brakes

9.9999E+03 TYawManS - Time to start yaw maneuver

9.9999E+03 TYawManE - Time to end yaw maneuver

0.0000E+00 NacYawF - Final nacelle-yaw angle for maneuvers

9.9999E+03 TPitManS(1) - Time to start pitch maneuvers

9.9999E+03 TPitManS(2) - Time to start pitch maneuvers

9.9999E+03 TPitManS(3) - Time to start pitch maneuvers

9.9999E+03 TPitManE(1) - Time to end pitch maneuvers

9.9999E+03 TPitManE(2) - Time to end pitch maneuvers

9.9999E+03 TPitManE(3) - Time to end pitch maneuvers

0.0000E+00 BlPitch(1) - Initial pitch angle

0.0000E+00 BlPitch(2) - Initial pitch angle

0.0000E+00 BlPitch(3) - Initial pitch angle

0.0000E+00 BlPitchF(1) - Final pitch angle for maneuvers

0.0000E+00 BlPitchF(2) - Final pitch angle for maneuvers

0.0000E+00 BlPitchF(3) - Final pitch angle for maneuvers

---------------------- ENVIRONMENTAL CONDITIONS --------------------------------

9.8067E+00 Gravity - Gravitational acceleration

---------------------- FEATURE FLAGS -------------------------------------------

T FlapDOF1 - First flapwise blade mode DOF

T FlapDOF2 - Second flapwise blade mode DOF

T EdgeDOF - First edgewise blade mode DOF

False TeetDOF - Rotor-teeter DOF (flag) [unused for 3 blades]

T DrTrDOF - Drivetrain rotational-flexibility DOF

F GenDOF - Generator DOF

T YawDOF - Yaw DOF

T TwFADOF1 - First tower fore-aft bending-mode DOF

T TwFADOF2 - Second tower fore-aft bending-mode DOF

T TwSSDOF1 - First tower side-to-side bending-mode DOF

T TwSSDOF2 - Second tower side-to-side bending-mode DOF

F CompAero - Compute aerodynamic forces

F CompNoise - Compute aerodynamic noise

---------------------- INITIAL CONDITIONS --------------------------------------

0.0000E+00 OoPDefl - Initial out-of-plane blade-tip deflection

0.0000E+00 IPDefl - Initial in-plane blade-tip deflection

0.0 TeetDefl - Initial or fixed teeter angle (degrees) [unused for 3 blades]

0.0000E+00 Azimuth - Initial azimuth position for blade 1

0.0000E+00 RotSpeed - Initial or fixed rotor speed

0.0000E+00 NacYaw - Initial or fixed nacelle-yaw angle

0.0000E+00 TTDspFA - Initial fore-aft tower-top displacement

0.0000E+00 TTDspSS - Initial side-to-side tower-top displacement

---------------------- TURBINE CONFIGURATION -----------------------------------

6.3000E+01 TipRad - Preconed blade-tip radius

1.5000E+00 HubRad - Preconed hub radius

1 PSpnElN - Number of the innermost blade element which is still part of the pitchable portion of the blade for partial-span pitch control [1 to BldNodes] [CURRENTLY IGNORED] (-)

0.0 UndSling - Undersling length [distance from teeter pin to the rotor apex] (meters) [unused for 3 blades]

0.0000E+00 HubCM - Distance from rotor apex to hub mass

-5.0191E+00 OverHang - Distance from yaw axis to rotor apex or teeter pin

1.9000E+00 NacCMxn - Downwind distance from tower-top to nacelle CM

0.0000E+00 NacCMyn - Lateral distance from tower-top to nacelle CM

1.7500E+00 NacCMzn - Vertical distance from tower-top to nacelle CM

8.7600E+01 TowerHt - Tower height

1.9626E+00 Twr2Shft - Vertical distance from tower-top to rotor shaft

0.0000E+00 TwrRBHt - Tower rigid base height

-5.0000E+00 ShftTilt - Rotor shaft tilt angle

0.0 Delta3 - Delta-3 angle for teetering rotors (degrees) [unused for 3 blades]

-2.5000E+00 PreCone(1) - Blade coning angle

-2.5000E+00 PreCone(2) - Blade coning angle

-2.5000E+00 PreCone(3) - Blade coning angle

0.0000E+00 AzimB1Up - Azimuth value to use for I/O when blade 1 points up

---------------------- MASS AND INERTIA ----------------------------------------

0.0000E+00 YawBrMass - Yaw bearing mass

2.4000E+05 NacMass - Nacelle mass

5.6780E+04 HubMass - Hub mass

0.0000E+00 TipMass(1) - Tip-brake mass

0.0000E+00 TipMass(2) - Tip-brake mass

0.0000E+00 TipMass(3) - Tip-brake mass

2.6079E+06 NacYIner - Nacelle yaw inertia

5.3412E+02 GenIner - Generator inertia about HSS

1.1593E+05 HubIner - Hub inertia about rotor axis

---------------------- DRIVETRAIN ----------------------------------------------

1.0000E+02 GBoxEff - Gearbox efficiency

9.4400E+01 GenEff - Generator efficiency

9.7000E+01 GBRatio - Gearbox ratio

F GBRevers - Gearbox reversal flag

2.8116E+04 HSSBrTqF - Fully deployed HSS brake torque

6.0000E-01 HSSBrDT - Time for HSS-brake to reach full deployment once initiated

DynBrkFi - File containing a mech-gen-torque vs HSS-speed curve for a dynamic brake [CURRENTLY IGNORED] (quoted string)

8.6764E+08 DTTorSpr - Drivetrain torsional spring

6.2150E+06 DTTorDmp - Drivetrain torsional damper

---------------------- SIMPLE INDUCTION GENERATOR ------------------------------

9.9999E+03 SIG_SlPc - Rated generator slip percentage

9.9999E+03 SIG_SySp - Synchronous (zero-torque) generator speed

9.9999E+03 SIG_RtTq - Rated torque

9.9999E+03 SIG_PORt - Pull-out ratio

---------------------- THEVENIN-EQUIVALENT INDUCTION GENERATOR -----------------

9.9999E+03 TEC_Freq - Line frequency

9998 TEC_NPol - Number of poles

9.9999E+03 TEC_SRes - Stator resistance

9.9999E+03 TEC_RRes - Rotor resistance

9.9999E+03 TEC_VLL - Line-to-line RMS voltage

9.9999E+03 TEC_SLR - Stator leakage reactance

9.9999E+03 TEC_RLR - Rotor leakage reactance

9.9999E+03 TEC_MR - Magnetizing reactance

---------------------- PLATFORM ------------------------------------------------

2 PtfmModel - Platform model switch

PtfmFile - Name of file containing platform properties

“E:/Seismic/linear/NRELOffshrBsline5MW_Onshore_Ptfm.dat”

---------------------- TOWER ---------------------------------------------------

20 TwrNodes - Number of tower nodes used for analysis

TwrFile - Name of file containing tower properties

“E:/Seismic/linear/NRELOffshrBsline5MW_Tower_Onshore.dat”

---------------------- NACELLE-YAW ---------------------------------------------

9.0283E+09 YawSpr - Nacelle-yaw spring constant

1.9160E+07 YawDamp - Nacelle-yaw damping constant

0.0000E+00 YawNeut - Neutral yaw position

---------------------- FURLING -------------------------------------------------

F Furling - Read in additional model properties for furling turbine

FurlFile - Name of file containing furling properties

“FurlFile”

---------------------- 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]

---------------------- TIP-BRAKE -----------------------------------------------

0.0000E+00 TBDrConN - Tip-brake drag constant during normal operation

0.0000E+00 TBDrConD - Tip-brake drag constant during fully-deployed operation

0.0000E+00 TpBrDT - Time for tip-brake to reach full deployment once released

---------------------- BLADE ---------------------------------------------------

BldFile(1) - Names of files containing blade properties

E:/Seismic/linear/NRELOffshrBsline5MW_Blade.dat

BldFile(2) - Names of files containing blade properties

E:/Seismic/linear/NRELOffshrBsline5MW_Blade.dat

BldFile(3) - Names of files containing blade properties

E:/Seismic/linear/NRELOffshrBsline5MW_Blade.dat

---------------------- AERODYN -------------------------------------------------

ADFile - Name of file containing AeroDyn parameters

“E:/Seismic/linear/NRELOffshrBsline5MW_AeroDyn.ipt”

---------------------- NOISE ---------------------------------------------------

NoiseFile - Name of file containing aerodynamic noise parameters

“NoiseFile”

---------------------- ADAMS ---------------------------------------------------

ADAMSFile - Name of file containing ADAMS-specific properties

“E:/Seismic/linear/NRELOffshrBsline5MW_ADAMSSpecific.dat”

---------------------- LINEARIZATION CONTROL -----------------------------------

LinFile - Name of file containing FAST linearization parameters

“E:/Seismic/linear/NRELOffshrBsline5MW_Linear.dat”

---------------------- OUTPUT --------------------------------------------------

T SumPrint - Print summary data to “*.fsm”

1 OutFileFmt - Format for output file(s)

T TabDelim - Use tab delimiters in text output file

OutFmt - Output format for text tabular data

“ES10.3E2”

0.0000E+00 TStart - Time to begin tabular output

1 DecFact - Decimation factor for tabular output

1.0000E+00 SttsTime - Amount of time between screen status messages

-3.0953E+00 NcIMUxn - Downwind distance from the tower-top to the nacelle IMU

0.0000E+00 NcIMUyn - Lateral distance from the tower-top to the nacelle IMU

2.2334E+00 NcIMUzn - Vertical distance from the tower-top to the nacelle IMU

1.9120E+00 ShftGagL - Distance from hub or teeter pin to shaft strain gages

0 NTwGages - Number of tower “strain-gage” output stations

TwrGagNd - List of tower nodes that have strain gages

```
3 NBlGages - Number of blade "strain-gage" output stations
BldGagNd - List of blade nodes that have strain gages
```

5 9 13

OutList - The next line(s) contains a list of output parameters. See OutList.txt for a listing of available output channels, (-)

OutList - Output list

“PtfmTDxi, PtfmTDyi, PtfmTDzi”

OutList - Output list

“PtfmTVxi, PtfmTVyi, PtfmTVzi”

OutList - Output list

“PtfmTAxi, PtfmTAyi, PtfmTAzi”

OutList - Output list

“PtfmTAxt , PtfmTAyt , PtfmTAzt”

OutList - Output list

“YawBrFxp , YawBrFyp , YawBrFzp”

OutList - Output list

“YawBrMxp , YawBrMyp , YawBrMzp”

OutList - Output list

“TwrBsFxt , TwrBsFyt , TwrBsFzt”

OutList - Output list

“TwrBsMxt , TwrBsMyt , TwrBsMzt”

OutList - Output list

“END”

Platform input data from file “E:/Seismic/linear/NRELOffshrBsline5MW_Onshore_Ptfm.dat”:

---------------------- FEATURE FLAGS (CONT) ------------------------------------

T PtfmSgDOF - Platform surge DOF

F PtfmSwDOF - Platform sway DOF

F PtfmHvDOF - Platform heave DOF

F PtfmRDOF - Platform roll DOF

F PtfmPDOF - Platform pitch DOF

F PtfmYDOF - Platform yaw DOF

---------------------- INITIAL CONDITIONS (CONT) -------------------------------

0.0000E+00 PtfmSurge - Initial or fixed platform surge

0.0000E+00 PtfmSway - Initial or fixed platform sway

0.0000E+00 PtfmHeave - Initial or fixed platform heave

0.0000E+00 PtfmRoll - Initial or fixed platform roll

0.0000E+00 PtfmPitch - Initial or fixed platform pitch

0.0000E+00 PtfmYaw - Initial or fixed platform yaw

---------------------- TURBINE CONFIGURATION (CONT) ----------------------------

2.0000E+01 TwrDraft - Downward distance from ground [onshore] or MSL [offshore] to tower base platform connection

2.0000E+01 PtfmCM - Downward distance from ground [onshore] or MSL [offshore] to platform CM

2.0000E+01 PtfmRef - Downward distance from ground [onshore] or MSL [offshore] to platform reference point

---------------------- MASS AND INERTIA (CONT) ---------------------------------

1.6000E+06 PtfmMass - Platform mass

0.0000E+00 PtfmRIner - Platform inertia for roll tilt rotation about the platform CM

0.0000E+00 PtfmPIner - Platform inertia for pitch tilt rotation about the platform CM

0.0000E+00 PtfmYIner - Platform inertia for yaw rotation about the platform CM

---------------------- PLATFORM (CONT) -----------------------------------------

0 PtfmLdMod - Platform loading model switch

---------------------- TOWER (CONT) --------------------------------------------

0 TwrLdMod - Tower loading model switch

6.0 TwrDiam - Tower diameter in Morison’s equation (meters) [used only when TwrLdMod=1]

1.0 TwrCA - Normalized hydrodynamic added mass coefficient in Morison’s equation (-) [used only when TwrLdMod=1] [determines TwrCM=1+TwrCA]

1.0 TwrCD - Normalized hydrodynamic viscous drag coefficient in Morison’s equation (-) [used only when TwrLdMod=1]

---------------------- WAVES ---------------------------------------------------

1.0270E+03 WtrDens - Water density

2.0000E+01 WtrDpth - Water depth

2 WaveMod - Wave kinematics model switch

0 WaveStMod - Model switch for stretching incident wave kinematics to instantaneous free surface

3.6300E+03 WaveTMax - Analysis time for incident wave calculations

2.5000E-01 WaveDT - Time step for incident wave calculations

5.0000E+00 WaveHs - Significant wave height

1.2400E+01 WaveTp - Peak spectral period

WavePkShp - Peak shape parameter

“DEFAULT”

0.0000E+00 WaveDir - Wave heading direction

123456789 WaveSeed(1) - First random seed

1011121314 WaveSeed(2) - Second random seed

True WaveNDAmp - Normally-distributed amplitudes in incident waves spectrum (flag) [used only when WaveMod=2 or 3]

“Dummy” GHWvFile - Root name of GH Bladed files containing wave data (quoted string) [used only when WaveMod=4]