Dear Jason,
I am simulating the offshore wind turbine of Oc4-jacket, I have some questions for the modal analysis, what is the second frequency of the whole system (including the substructure) of Oc4-jacket? If not, can bmodes calculate the second frequency of the whole system?
Looking forward to your reply and thank you for your kindness!
Best regards,
Zhou.Lin
Dear Zhou.Lin,
According to the OC4 Phase I results (nrel.gov/docs/fy12osti/54124.pdf), the second global bending frequency of the tower + jacket of the OC4-jacket is around 1.2 Hz.
BModes can calculate tower natural frequencies, but the jacket must be simplified in BModes as a tower-base boundary condition involving 6x6 mass and stiffness matrices, which can be derived from the SubDyn summary file (hydro_M = MBBt, hydro_K = KBBt, mooring_K = 0).
I hope that helps.
Best regards,
Dear @Jason.Jonkman
For the OC4 jacket model (5MW_OC4Jckt_DLL_WTurb_WavesIrr_MGrowth.fst), could you please tell me where can I obtain more DISTRIBUTED TOWER PROPERTIES information such as “torsion stiffness (TWGJstff)”, “axial stiffness (TwEAStff)”, “fore-aft inertia (TwFAIner)”, “side-to-side inertia (TwSSIner)”. In my understanding these tower section properties must be known and input to BModes to calculate and update the tower mode shapes. However, I cannot find any corresponding information except for TMassDen, TwFAStif, TwSSStif as follows ( from NRELOffshrBsline5MW_OC4Jacket_ElastoDyn_Tower.dat).
------- ELASTODYN V1.00.* TOWER INPUT FILE -------------------------------------
NREL 5.0 MW offshore baseline OC4 tower with flexible Jacket SubStructure (however SS cantilevered at seabed).
---------------------- TOWER PARAMETERS ----------------------------------------
22 NTwInpSt - Number of input stations to specify tower geometry
1 TwrFADmp(1) - Tower 1st fore-aft mode structural damping ratio (%)
1 TwrFADmp(2) - Tower 2nd fore-aft mode structural damping ratio (%)
1 TwrSSDmp(1) - Tower 1st side-to-side mode structural damping ratio (%)
1 TwrSSDmp(2) - Tower 2nd side-to-side mode structural damping ratio (%)
---------------------- TOWER ADJUSTMUNT FACTORS --------------------------------
1 FAStTunr(1) - Tower fore-aft modal stiffness tuner, 1st mode (-)
1 FAStTunr(2) - Tower fore-aft modal stiffness tuner, 2nd mode (-)
1 SSStTunr(1) - Tower side-to-side stiffness tuner, 1st mode (-)
1 SSStTunr(2) - Tower side-to-side stiffness tuner, 2nd mode (-)
1 AdjTwMa - Factor to adjust tower mass density (-)
1 AdjFASt - Factor to adjust tower fore-aft stiffness (-)
1 AdjSSSt - Factor to adjust tower side-to-side stiffness (-)
---------------------- DISTRIBUTED TOWER PROPERTIES ----------------------------
HtFract TMassDen TwFAStif TwSSStif
(-) (kg/m) (Nm^2) (Nm^2)
0.000 4900.472786 4.5556E+11 4.5556E+11
0.025 4900.472786 4.4419E+11 4.4419E+11
0.075 4200.272421 4.1707E+11 4.1707E+11
0.125 4057.180384 3.9120E+11 3.9120E+11
0.175 3915.575049 3.6655E+11 3.6655E+11
0.225 3770.476234 3.4234E+11 3.4234E+11
0.275 3626.859482 3.1932E+11 3.1932E+11
0.325 3477.860118 2.9733E+11 2.9733E+11
0.375 3291.027294 2.7214E+11 2.7214E+11
0.425 3102.11339 2.4846E+11 2.4846E+11
0.475 3123.48485 2.2622E+11 2.2622E+11
0.525 2969.643543 2.0732E+11 2.0732E+11
0.575 2639.437112 1.9143E+11 1.9143E+11
0.625 2517.768961 1.7644E+11 1.7644E+11
0.675 2398.659195 1.6232E+11 1.6232E+11
0.725 2282.133754 1.4902E+11 1.4902E+11
0.775 2173.8144 1.3653E+11 1.3653E+11
0.825 2344.181633 1.4213E+11 1.4213E+11
0.875 2687.066514 1.5659E+11 1.5659E+11
0.925 2971.054769 1.6870E+11 1.6870E+11
0.975 3260.985159 1.5955E+11 1.5955E+11
1.000 3260.985159 1.5481E+11 1.5481E+11
---------------------- TOWER FORE-AFT MODE SHAPES ------------------------------
1.0221 TwFAM1Sh(2) - Mode 1, coefficient of x^2 term
0.0483 TwFAM1Sh(3) - , coefficient of x^3 term
-0.0948 TwFAM1Sh(4) - , coefficient of x^4 term
0.2283 TwFAM1Sh(5) - , coefficient of x^5 term
-0.2039 TwFAM1Sh(6) - , coefficient of x^6 term
0.6197 TwFAM2Sh(2) - Mode 2, coefficient of x^2 term
0.5380 TwFAM2Sh(3) - , coefficient of x^3 term
-0.4478 TwFAM2Sh(4) - , coefficient of x^4 term
0.7483 TwFAM2Sh(5) - , coefficient of x^5 term
-0.4582 TwFAM2Sh(6) - , coefficient of x^6 term
---------------------- TOWER SIDE-TO-SIDE MODE SHAPES --------------------------
1.0034 TwSSM1Sh(2) - Mode 1, coefficient of x^2 term
0.0700 TwSSM1Sh(3) - , coefficient of x^3 term
-0.1377 TwSSM1Sh(4) - , coefficient of x^4 term
0.2943 TwSSM1Sh(5) - , coefficient of x^5 term
-0.2300 TwSSM1Sh(6) - , coefficient of x^6 term
0.5250 TwSSM2Sh(2) - Mode 2, coefficient of x^2 term
0.6536 TwSSM2Sh(3) - , coefficient of x^3 term
-0.6967 TwSSM2Sh(4) - , coefficient of x^4 term
1.1231 TwSSM2Sh(5) - , coefficient of x^5 term
-0.6049 TwSSM2Sh(6) - , coefficient of x^6 term
In addition, Is there any other text or supporting document (such as relevant elastodyn.dat & elastodyn_tower.dat) and description corresponding to the following link.
https://openfast.readthedocs.io/en/main/source/user/subdyn/appendixA.html
https://openfast.readthedocs.io/en/main/source/user/subdyn/appendixC.html
Thank you for your assitance and time.
Best regards,
Dear Baoxuan,
Normally, you can assign a very large value for “torsion stiffness (TWGJstff )”, “axial stiffness (TwEAStff )”, and very small value for “fore-aft inertia (TwFAIner )” ,“fore-aft inertia (TwFAIner )”, “side-to-side inertia (TwSSIner )”. It will not influence the results, as discussed in below link.
https://forums.nrel.gov/t/blade-mode-shapes-with-bmodes/1441?u=ran.tu
Dear @Jason.Jonkman ,
I modeled entire tower in Subdyn. When I look through the Subdyn summary file, I am confused by MBBt.
Mass: 3.473670E+05 # Total Mass
CM_point: [ 0.000000E+00, 0.000000E+00, 3.818261E+01,] # Center of mass coordinates (Xcm,Ycm,Zcm)
TP_point: [ 0.000000E+00, 0.000000E+00, 8.759900E+01,] # Transition piece reference point
MRB: # 6 x 6 Rigid Body Equivalent Mass Matrix w.r.t. (0,0,0).
- [ 3.473670E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00, 1.326338E+07, 0.000000E+00]
- [ 0.000000E+00, 3.473670E+05, 0.000000E+00, -1.326338E+07, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 3.473670E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, -1.326338E+07, 0.000000E+00, 7.209051E+08, 0.000000E+00, 0.000000E+00]
- [ 1.326338E+07, 0.000000E+00, 0.000000E+00, 0.000000E+00, 7.209051E+08, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 2.238086E+06]
M_P: # 6 x 6 Rigid Body Equivalent Mass Matrix w.r.t. TP Ref point
- [ 3.473670E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00, -1.716562E+07, 0.000000E+00]
- [ 0.000000E+00, 3.473670E+05, 0.000000E+00, 1.716562E+07, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 3.473670E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 1.716562E+07, 0.000000E+00, 1.062738E+09, 0.000000E+00, 0.000000E+00]
- [ -1.716562E+07, 0.000000E+00, 0.000000E+00, 0.000000E+00, 1.062738E+09, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 2.238086E+06]
M_G: # 6 x 6 Rigid Body Equivalent Mass Matrix w.r.t. CM (Xcm,Ycm,Zcm).
- [ 3.473670E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 3.473670E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 3.473670E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 0.000000E+00, 2.144748E+08, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 2.144748E+08, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 2.238086E+06]
#____________________________________________________________________________________________________
# GUYAN MATRICES at the TP reference point
#____________________________________________________________________________________________________
KBBt: # 6 x 6
- [ 5.045149E+06, 0.000000E+00, 0.000000E+00, 0.000000E+00, -1.613169E+08, 0.000000E+00]
- [ 0.000000E+00, 5.045149E+06, 0.000000E+00, 1.613169E+08, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 1.062429E+09, 0.000000E+00, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 1.613169E+08, 0.000000E+00, 8.035837E+09, 0.000000E+00, 0.000000E+00]
- [ -1.613169E+08, 0.000000E+00, 0.000000E+00, 0.000000E+00, 8.035837E+09, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 2.214521E+09]
MBBt: # 6 x 6
- [ 8.577564E+04, 0.000000E+00, 0.000000E+00, 0.000000E+00, -8.880862E+05, 0.000000E+00]
- [ 0.000000E+00, 8.577564E+04, 0.000000E+00, 8.880862E+05, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 7.412644E+04, 0.000000E+00, 0.000000E+00, 0.000000E+00]
- [ 0.000000E+00, 8.880862E+05, 0.000000E+00, 1.142198E+07, 0.000000E+00, 0.000000E+00]
- [ -8.880862E+05, 0.000000E+00, 0.000000E+00, 0.000000E+00, 1.142198E+07, 0.000000E+00]
- [ 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 2.609863E+05]
I am not using MBBt in BModes. I am just confused what MBBt mean. MBBt seems to be the added mass matrix?
If I used this summary file to BModes (just for example), I want to confirm whether:
Platform mass inertia 3X3 matrix (i_matrix_pform) should use M_G (4, 4), M_G (5, 5), M_G (6, 6)?
Regards,
Ran
Dear @Ran.Tu,
Thank you for answering @Baoxuan.Wang questions.
Regarding MBBt and KBBt, these are the mass and stiffness matrices associated with the Guyan modes. See the online SubDyn documentation for more information on the Guyan modes and Craig-Bampton reduction used by SubDyn: 4.2.5.6. SubDyn Theory — OpenFAST v3.3.0 documentation.
The platform inertia needed as input to BModes (i_matrix_pform) is the 3x3 inertia matrix relative to the platform center of mass. You can take the lower-right 3x3 submatrix of the rigid body equivalent mass matrix w.r.t. CM from the SubDyn summary file output, i.e., M_G(4:6,4:6).
Best regards,
Dear @Jason.Jonkman ,@Ran.Tu,
Thank you for your replies.This is very helpful.
Dear @Jason.Jonkman
Is there any other text or supporting document (such as relevant elastodyn_tower.dat) and description or more information (such as real soil propertities related to the OC4 Jacket SSI file stiffness matrix) corresponding to the previous links?
https://openfast.readthedocs.io/en/main/source/user/subdyn/appendixC.html
Strangely, tower parameters “TWGJstff ”, “TwEAStff ”, “TwFAIner” ,“TwFAIner ”, “TwSSIner” can be found for other CertTest samples such as OC3 tests and OC4 floating tests, except for OC4 jacket. Therefore, I am worried that I may have missed and neglected some important documents.
Thank you very much.
Best regards
Dear @Baoxuan.Wang,
I’m sorry, but I’m not really sure I understand your question. Please clarify.
Best regards,
Dear @Jason.Jonkman
Sorry.
I mean, have these parameters ( “TWGJstff ”, “TwEAStff ”, “TwFAIner ” ,“TwFAIner ”, “TwSSIner ”) been given for the tower model of oc4 jacket model? I cannot find them in related Technical Report.
For Appendix C. OC4 Jacket SSI Input File, is there any corresponding more description information (such as soil types, soil profile…)?
Best regards,
Dear @Baoxuan.Wang,
You should be able to calculate these sectional properties of the OC4 jacket (if you need them) based on the documented diameter, thickness, and material properties. See the OC4 jacket documentation here: Vorpahl et al. (2013) - OC4 Jacket Model Description.pdf - Google Drive.
This documentation, however, assumes a clamped boundary condition at the seabed. I’m not sure where the data in Appendix C came from. This is a better question for @Emmanuel.Branlard.
Best regards,
Dear Jason.Jonkman
Okay, thank you for your reply.
Best regards.
The data was generated by a former colleague, we are looking into where it might have come from, but it might take some weeks. Sorry about that.
Dear Emmanuel.Branlard
Thank you.
Best regards,
Dear @Jason.Jonkman,
Sorry to bother you again.
According to your previous suggestions, the “torsion stiffness (TWGJstff )”, “axial stiffness (TwEAStff )”, “fore-aft inertia (TwFAIner )”, “side-to-side inertia (TwSSIner )” in DISTRIBUTED TOWER PROPERTIES of OC4Jacket model were set by me as follows
Tower section properties
22 n_secs: number of tower sections at which properties are specified (-)
sec_loc str_tw tw_iner mass_den flp_iner edge_iner flp_stff edge_stff tor_stff axial_stff cg_offst sc_offst tc_offst
(-) (deg) (deg) (kg/m) (kg-m) (kg-m) (Nm^2) (Nm^2) (Nm^2) (N) (m) (m) (m)
0.000 0.0 0.0 4900.472786 1.0E-8 1.0E-8 4.5556E+11 4.5556E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.025 0.0 0.0 4900.472786 1.0E-8 1.0E-8 4.4419E+11 4.4419E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.075 0.0 0.0 4200.272421 1.0E-8 1.0E-8 4.1707E+11 4.1707E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.125 0.0 0.0 4057.180384 1.0E-8 1.0E-8 3.9120E+11 3.9120E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.175 0.0 0.0 3915.575049 1.0E-8 1.0E-8 3.6655E+11 3.6655E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.225 0.0 0.0 3770.476234 1.0E-8 1.0E-8 3.4234E+11 3.4234E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.275 0.0 0.0 3626.859482 1.0E-8 1.0E-8 3.1932E+11 3.1932E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.325 0.0 0.0 3477.860118 1.0E-8 1.0E-8 2.9733E+11 2.9733E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.375 0.0 0.0 3291.027294 1.0E-8 1.0E-8 2.7214E+11 2.7214E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.425 0.0 0.0 3102.11339 1.0E-8 1.0E-8 2.4846E+11 2.4846E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.475 0.0 0.0 3123.48485 1.0E-8 1.0E-8 2.2622E+11 2.2622E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.525 0.0 0.0 2969.643543 1.0E-8 1.0E-8 2.0732E+11 2.0732E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.575 0.0 0.0 2639.437112 1.0E-8 1.0E-8 1.9143E+11 1.9143E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.625 0.0 0.0 2517.768961 1.0E-8 1.0E-8 1.7644E+11 1.7644E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.675 0.0 0.0 2398.659195 1.0E-8 1.0E-8 1.6232E+11 1.6232E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.725 0.0 0.0 2282.133754 1.0E-8 1.0E-8 1.4902E+11 1.4902E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.775 0.0 0.0 2173.8144 1.0E-8 1.0E-8 1.3653E+11 1.3653E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.825 0.0 0.0 2344.181633 1.0E-8 1.0E-8 1.4213E+11 1.4213E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.875 0.0 0.0 2687.066514 1.0E-8 1.0E-8 1.5659E+11 1.5659E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.925 0.0 0.0 2971.054769 1.0E-8 1.0E-8 1.6870E+11 1.6870E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
0.975 0.0 0.0 3260.985159 1.0E-8 1.0E-8 1.5955E+11 1.5955E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
1.000 0.0 0.0 3260.985159 1.0E-8 1.0E-8 1.5481E+11 1.5481E+11 1.0E+16 1.0E+16 0.0 0.0 0.0
**Note: If the above data represents TOWER properties, the following are overwritten:
str_tw is set to zero
tw_iner is set to zero
cg_offst is set to zero
sc_offst is set to zero
tc_offst is set to zero
edge_iner is set equal to flp_iner
edge_stff is set equal to flp_stff
====================== BModes v3.00 Main Input File ==================
NREL 5MW OC4 Jacket Tower (Rigid foundation) WBX20220902
--------- General parameters ---------------------------------------------------------------------
true Echo Echo input file contents to *.echo file if true.
2 beam_type 1: blade, 2: tower (-)
0. romg: rotor speed, automatically set to zero for tower modal analysis (rpm)
1. romg_mult: rotor speed muliplicative factor (-)
88.15 radius: rotor tip radius measured along coned blade axis, OR tower height above ground level [onshore] or MSL [offshore](m)
0.0 hub_rad: hub radius measured along coned blade axis OR tower rigid-base height (m)
0. precone: built-in precone angle, automatically set to zero for a tower (deg)
0. bl_thp: blade pitch setting, automatically set to zero for a tower (deg)
2 hub_conn: hub-to-blade or tower-base boundary condition [1: cantilevered; 2: free-free; 3: only axial and torsion constraints] (-)
20 modepr: number of modes to be printed (-)
t TabDelim (true: tab-delimited output tables; false: space-delimited tables)
f mid_node_tw (true: output twist at mid-node of elements; false: no mid-node outputs)
--------- Blade-tip or tower-top mass properties --------------------------------------------
3.500003109E+005 tip_mass blade-tip or tower-top mass (kg)
-0.4137754432 cm_loc tip-mass c.m. offset from the tower axis measured along x-tower axis (m)
1.9669893542 cm_axial tip-mass c.m. offset tower tip measures axially along the z axis (m)
4.370E7 ixx_tip blade lag mass moment of inertia about the tip-section x reference axis (kg-m^2)
2.353E7 iyy_tip blade flap mass moment of inertia about the tip-section y reference axis (kg-m^2)
2.542E7 izz_tip torsion mass moment of inertia about the tip-section z reference axis (kg-m^2)
0. ixy_tip cross product of inertia about x and y reference axes(kg-m^2)
1.169E6 izx_tip cross product of inertia about z and x reference axes(kg-m^2)
0. iyz_tip cross product of inertia about y and z reference axes(kg-m^2)
--------- Distributed-property identifiers --------------------------------------------------------
1 id_mat: material_type [1: isotropic; non-isotropic composites option not yet available]
'CS_monopile_tower_secs.dat' : sec_props_file name of beam section properties file (-)
Property scaling factors..............................
1.0 sec_mass_mult: mass density multiplier (-)
1.0 flp_iner_mult: blade flap or tower f-a inertia multiplier (-)
1.0 lag_iner_mult: blade lag or tower s-s inertia multiplier (-)
1.0 flp_stff_mult: blade flap or tower f-a bending stiffness multiplier (-)
1.0 edge_stff_mult: blade lag or tower s-s bending stiffness multiplier (-)
1.0 tor_stff_mult: torsion stiffness multiplier (-)
1.0 axial_stff_mult: axial stiffness multiplier (-)
1.0 cg_offst_mult: cg offset multiplier (-)
1.0 sc_offst_mult: shear center multiplier (-)
1.0 tc_offst_mult: tension center multiplier (-)
--------- Finite element discretization --------------------------------------------------
50 nselt: no of blade or tower elements (-)
Distance of element boundary nodes from blade or flexible-tower root (normalized wrt blade or tower length), el_loc()
0.0000 0.0200 0.0400 0.0600 0.0800 0.1000 0.1200 0.1400 0.1600 0.1800 0.2000 0.2200 0.2400 0.2600 0.2800 0.3000 0.3200 0.3400 0.3600 0.3800 0.4000 0.4200 0.4400 0.4600 0.4800 0.5000 0.5200 0.5400 0.5600 0.5800 0.6000 0.6200 0.6400 0.6600 0.6800 0.7000 0.7200 0.7400 0.7600 0.7800 0.8000 0.8200 0.8400 0.8600 0.8800 0.9000 0.9200 0.9400 0.9600 0.9800 1.0000
--------- Properties of tower support subsystem (read only if beam_type is 2) ------------
1 tow_support: : aditional tower support [0: no additional support; 1: floating-platform or monopile with or without tension wires] (-)
-20.15 draft : depth of tower base from the ground or the MSL (mean sea level) (m)
-18.15 cm_pform : distance of platform c.m. below the MSL (m)
666000 mass_pform : platform mass (kg)
Platform mass inertia 3X3 matrix (i_matrix_pform):
6.00288E+06 0. 0.
0. 6.00288E+06 0.
0. 0. 1.02298E+07
-20.15 ref_msl : distance of platform reference point below the MSL (m)
Platform-reference-point-referred hydrodynamic 6X6 matrix (hydro_M):
1.811587E+05, -7.503331E-12, -4.365575E-11, -1.249191E-09, -1.616692E+06, -5.456968E-10
-5.229595E-12, 1.811587E+05, 1.455192E-11, 1.616692E+06, 2.337401E-10, 1.193257E-09
-3.183231E-11, 1.818989E-12, 1.933164E+05, -1.236913E-10, -5.857146E-10, 1.147896E-09
-1.306034E-09, 1.616692E+06, -1.164153E-10, 2.163200E+07, 1.774606E-08, 1.518492E-08
-1.616692E+06, 2.146407E-10, -3.492460E-10, 1.680019E-08, 2.163200E+07, 5.820766E-09
-5.820766E-10, 1.135049E-09, 1.243165E-09, 1.458011E-08, 5.848960E-09, 5.716638E+06
Platform-reference-point-referred hydrodynamic 6X6 stiffness matrix (hydro_K):
8.819354E+07, 2.374873E-08, 2.324581E-06, 1.744088E-05, -2.231230E+09, 3.308058E-06
-8.428469E-08, 8.819354E+07, -1.251698E-06, 2.231230E+09, -6.952323E-06, -1.952052E-06
1.423061E-06, -1.527369E-07, 1.992617E+09, -6.049871E-06, -1.603365E-05, -4.583654E-06
7.301569E-06, 2.231230E+09, -7.629395E-06, 1.024845E+11, 1.704693E-05, -5.130470E-05
-2.231230E+09, -4.693866E-06, -7.629395E-06, -1.016259E-04, 1.024845E+11, -1.139939E-06
3.814697E-06, -2.861023E-06, -8.999962E-06, -3.311038E-05, -6.407499E-06, 8.457470E+09
Mooring-system 6X6 stiffness matrix (mooring_K):
0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00
0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00
0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00
0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00
0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00
0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00, 0.000000E+00
Distributed (hydrodynamic) added-mass per unit length along a flexible portion of the tower length:
0 n_secs_m_distr: number of sections at which added mass per unit length is specified (-)
0. 0. : z_distr_m [row array of size n_added_m_pts; section locations wrt the flexible tower base over which distributed mass is specified] (m)
0. 0. : distr_m [row array of size n_added_m_pts; added distributed masses per unit length] (kg/m)
Distributed elastic stiffness per unit length along a flexible portion of the tower length:
0 n_secs_k_distr: number of points at which distributed stiffness per unit length is specified (-)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 : z_distr_k [row array of size n_added_m_pts; section locations wrt the flexible tower base over which distributed stiffness is specified] (m)
595318000.0 1165208000 1129400000 1095553000 1059931000 1024493000 989209000 953643000 918718000 883287000 847803000 812541000 777187000 741870000 706616000 671440000 636229000 600957000 565919000 530470000 495081000 459574000 385327000 305479000 280059000 254125000 227500000 200112000 171927000 143115000 114173000 80184000 52237000 35561000 20912000 9000000 1156000 : distr_k [row array of size n_added_m_pts; distributed stiffness per unit length] (N/m^2)
Tension wires data
0 n_attachments: no of wire-attachment locations on tower [0: no tension wires] (-)
3 3 n_wires: no of wires attached at each location (must be 3 or higher) (-)
6 9 node_attach: node numbers of attacments location (node number must be more than 1 and less than nselt+2) (-)
0.e0 0.e0 wire_stfness: wire spring constant in each set (see users' manual) (N/m)
0. 0. th_wire: angle of tension wires (wrt the horizontal ground plane) at each attachment point (deg)
END of Main Input File Data *********************************************************************
*************************************************************************************************
Last, I have obtained the modal analysis results as follows:
Running BModes (v1.03.01, 25-Sept-2007, compiled using double precision).
Linked with the NWTC Subroutine Library (v1.01.08, 26-Sep-2007).
all parameters checked : o.k.
******** modal analysis results **********
eigenvalue( 1) = 0.368495D+11 mode 1 frequency = 0.319937
eigenvalue( 2) = 0.374908D+11 mode 2 frequency = 0.322709
eigenvalue( 3) = 0.483076D+12 mode 3 frequency = 1.158395
eigenvalue( 4) = 0.514378D+12 mode 4 frequency = 1.195336
eigenvalue( 5) = 0.186188D+13 mode 5 frequency = 2.274181
eigenvalue( 6) = 0.218418D+13 mode 6 frequency = 2.463160
eigenvalue( 7) = 0.319694D+13 mode 7 frequency = 2.979998
eigenvalue( 8) = 0.162584D+14 mode 8 frequency = 6.720290
eigenvalue( 9) = 0.180729D+14 mode 9 frequency = 7.085367
eigenvalue( 10) = 0.564525D+14 mode 10 frequency = 12.522481
eigenvalue( 11) = 0.576765D+14 mode 11 frequency = 12.657509
eigenvalue( 12) = 0.166495D+15 mode 12 frequency = 21.505493
eigenvalue( 13) = 0.168981D+15 mode 13 frequency = 21.665443
eigenvalue( 14) = 0.523197D+15 mode 14 frequency = 38.122486
eigenvalue( 15) = 0.526385D+15 mode 15 frequency = 38.238464
eigenvalue( 16) = 0.135523D+16 mode 16 frequency = 61.355680
eigenvalue( 17) = 0.135901D+16 mode 17 frequency = 61.441292
eigenvalue( 18) = 0.292881D+16 mode 18 frequency = 90.197394
eigenvalue( 19) = 0.293304D+16 mode 19 frequency = 90.262635
eigenvalue( 20) = 0.566409D+16 mode 20 frequency = 125.433587
BModes terminated normally.
However, to my surprise, the content (especially for s-s disp).out file that BModes created is strange, and I cannot distinguish the tower modes, as we can see as follows 
Results generated by BModes (v1.03.01, 25-Sept-2007, compiled using double precision) on 02-Sep-2022 at 15:30:40.
NREL 5MW OC4 Jacket Tower (Rigid foundation) WBX20220902
=================================================================================
tower frequencies & mode shapes
--- only first 20 modes printed
-------- Mode No. 1 (freq = 0.319937E+00 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.000003 0.000007 -0.015808 -0.033785 0.000000
0.0200 0.000004 0.000008 -0.016516 -0.036987 0.000000
0.0400 0.000004 0.000009 -0.017287 -0.040190 0.000000
0.0600 0.000004 0.000010 -0.018124 -0.043405 0.000000
0.0800 0.000004 0.000010 -0.019024 -0.046632 0.000000
0.1000 0.000004 0.000011 -0.019989 -0.049869 0.000000
0.1200 0.000005 0.000012 -0.021019 -0.053116 0.000000
0.1400 0.000005 0.000012 -0.022114 -0.056373 0.000000
0.1600 0.000005 0.000013 -0.023274 -0.059637 0.000000
0.1800 0.000005 0.000014 -0.024500 -0.062908 0.000000
0.2000 0.000006 0.000015 -0.025791 -0.066186 0.000000
0.2200 0.000006 0.000015 -0.027148 -0.069471 0.000000
0.2400 0.000006 0.000016 -0.028570 -0.072763 0.000000
0.2600 0.000007 0.000017 -0.030059 -0.076058 0.000000
0.2800 0.000007 0.000018 -0.031613 -0.079358 0.000000
0.3000 0.000007 0.000018 -0.033233 -0.082658 0.000000
0.3200 0.000008 0.000019 -0.034920 -0.085959 0.000000
0.3400 0.000008 0.000020 -0.036672 -0.089265 0.000000
0.3600 0.000009 0.000020 -0.038491 -0.092586 0.000000
0.3800 0.000009 0.000021 -0.040376 -0.095925 0.000000
0.4000 0.000009 0.000022 -0.042328 -0.099278 0.000000
0.4200 0.000010 0.000023 -0.044348 -0.102644 0.000000
0.4400 0.000010 0.000023 -0.046434 -0.106022 0.000000
0.4600 0.000011 0.000024 -0.048589 -0.109407 0.000000
0.4800 0.000011 0.000025 -0.050811 -0.112801 0.000000
0.5000 0.000012 0.000026 -0.053101 -0.116189 0.000000
0.5200 0.000012 0.000026 -0.055459 -0.119567 0.000000
0.5400 0.000013 0.000027 -0.057884 -0.122928 0.000000
0.5600 0.000013 0.000028 -0.060376 -0.126258 0.000000
0.5800 0.000014 0.000029 -0.062935 -0.129554 0.000000
0.6000 0.000015 0.000029 -0.065559 -0.132810 0.000000
0.6200 0.000015 0.000030 -0.068247 -0.136023 0.000000
0.6400 0.000016 0.000031 -0.070999 -0.139189 0.000000
0.6600 0.000016 0.000031 -0.073815 -0.142300 0.000000
0.6800 0.000017 0.000032 -0.076691 -0.145354 0.000000
0.7000 0.000018 0.000033 -0.079629 -0.148342 0.000000
0.7200 0.000018 0.000033 -0.082625 -0.151259 0.000000
0.7400 0.000019 0.000034 -0.085679 -0.154100 0.000000
0.7600 0.000020 0.000035 -0.088789 -0.156854 0.000000
0.7800 0.000020 0.000035 -0.091953 -0.159517 0.000000
0.8000 0.000021 0.000036 -0.095168 -0.161981 0.000000
0.8200 0.000022 0.000036 -0.098430 -0.164221 0.000000
0.8400 0.000023 0.000037 -0.101735 -0.166232 0.000000
0.8600 0.000023 0.000037 -0.105078 -0.167992 0.000000
0.8800 0.000024 0.000038 -0.108453 -0.169522 0.000000
0.9000 0.000025 0.000038 -0.111857 -0.170845 0.000000
0.9200 0.000026 0.000038 -0.115286 -0.171976 0.000000
0.9400 0.000026 0.000038 -0.118735 -0.172941 0.000000
0.9600 0.000027 0.000038 -0.122202 -0.173776 0.000000
0.9800 0.000028 0.000039 -0.125685 -0.174478 0.000000
1.0000 0.000029 0.000039 -0.129181 -0.175043 0.000000
-------- Mode No. 2 (freq = 0.322709E+00 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.000000 0.000000 -0.016010 -0.034140 0.000000
0.0200 0.000000 0.000000 -0.016725 -0.037359 0.000000
0.0400 0.000000 0.000000 -0.017504 -0.040578 0.000000
0.0600 0.000000 0.000000 -0.018348 -0.043809 0.000000
0.0800 0.000000 0.000000 -0.019257 -0.047050 0.000000
0.1000 0.000000 0.000000 -0.020231 -0.050301 0.000000
0.1200 0.000000 0.000000 -0.021269 -0.053561 0.000000
0.1400 0.000000 0.000000 -0.022373 -0.056829 0.000000
0.1600 0.000000 0.000000 -0.023543 -0.060102 0.000000
0.1800 0.000000 0.000000 -0.024778 -0.063382 0.000000
0.2000 0.000000 0.000000 -0.026078 -0.066667 0.000000
0.2200 0.000000 0.000000 -0.027445 -0.069959 0.000000
0.2400 0.000000 0.000000 -0.028877 -0.073255 0.000000
0.2600 0.000000 0.000000 -0.030375 -0.076553 0.000000
0.2800 0.000000 0.000000 -0.031940 -0.079853 0.000000
0.3000 0.000000 0.000000 -0.033570 -0.083153 0.000000
0.3200 0.000000 0.000000 -0.035266 -0.086452 0.000000
0.3400 0.000000 0.000000 -0.037028 -0.089752 0.000000
0.3600 0.000000 0.000000 -0.038857 -0.093067 0.000000
0.3800 0.000000 0.000000 -0.040751 -0.096397 0.000000
0.4000 0.000000 0.000000 -0.042713 -0.099739 0.000000
0.4200 0.000000 0.000000 -0.044741 -0.103090 0.000000
0.4400 0.000000 0.000000 -0.046837 -0.106452 0.000000
0.4600 0.000000 0.000000 -0.049000 -0.109818 0.000000
0.4800 0.000000 0.000000 -0.051230 -0.113189 0.000000
0.5000 0.000000 0.000000 -0.053528 -0.116551 0.000000
0.5200 0.000000 0.000000 -0.055893 -0.119899 0.000000
0.5400 0.000000 0.000000 -0.058324 -0.123228 0.000000
0.5600 0.000000 0.000000 -0.060822 -0.126520 0.000000
0.5800 0.000000 0.000000 -0.063385 -0.129776 0.000000
0.6000 0.000000 0.000000 -0.066013 -0.132987 0.000000
0.6200 0.000000 0.000000 -0.068704 -0.136151 0.000000
0.6400 0.000000 0.000000 -0.071459 -0.139263 0.000000
0.6600 0.000000 0.000000 -0.074275 -0.142316 0.000000
0.6800 0.000000 0.000000 -0.077151 -0.145306 0.000000
0.7000 0.000000 0.000000 -0.080087 -0.148225 0.000000
0.7200 0.000000 0.000000 -0.083080 -0.151067 0.000000
0.7400 0.000000 0.000000 -0.086129 -0.153826 0.000000
0.7600 0.000000 0.000000 -0.089233 -0.156493 0.000000
0.7800 0.000000 0.000000 -0.092389 -0.159061 0.000000
0.8000 0.000000 0.000000 -0.095594 -0.161429 0.000000
0.8200 0.000000 0.000000 -0.098844 -0.163569 0.000000
0.8400 0.000000 0.000000 -0.102135 -0.165479 0.000000
0.8600 0.000000 0.000000 -0.105462 -0.167139 0.000000
0.8800 0.000000 0.000000 -0.108819 -0.168570 0.000000
0.9000 0.000000 0.000000 -0.112203 -0.169793 0.000000
0.9200 0.000000 0.000000 -0.115609 -0.170825 0.000000
0.9400 0.000000 0.000000 -0.119035 -0.171690 0.000000
0.9600 0.000000 0.000000 -0.122476 -0.172420 0.000000
0.9800 0.000000 0.000000 -0.125931 -0.173011 0.000000
1.0000 0.000000 0.000000 -0.129396 -0.173460 0.000000
-------- Mode No. 3 (freq = 0.115839E+01 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.000049 0.000061 -0.061002 -0.075311 0.000003
0.0200 0.000050 0.000058 -0.062478 -0.072218 0.000003
0.0400 0.000051 0.000055 -0.063890 -0.068966 0.000003
0.0600 0.000052 0.000053 -0.065235 -0.065544 0.000003
0.0800 0.000053 0.000050 -0.066510 -0.061951 0.000003
0.1000 0.000054 0.000047 -0.067711 -0.058185 0.000003
0.1200 0.000055 0.000044 -0.068836 -0.054247 0.000003
0.1400 0.000056 0.000040 -0.069880 -0.050135 0.000003
0.1600 0.000057 0.000037 -0.070840 -0.045849 0.000003
0.1800 0.000058 0.000033 -0.071712 -0.041388 0.000003
0.2000 0.000058 0.000030 -0.072494 -0.036751 0.000003
0.2200 0.000059 0.000026 -0.073181 -0.031936 0.000003
0.2400 0.000059 0.000022 -0.073769 -0.026942 0.000003
0.2600 0.000060 0.000017 -0.074257 -0.021772 0.000003
0.2800 0.000060 0.000013 -0.074639 -0.016423 0.000003
0.3000 0.000060 0.000009 -0.074912 -0.010898 0.000003
0.3200 0.000060 0.000004 -0.075073 -0.005197 0.000003
0.3400 0.000060 -0.000001 -0.075118 0.000690 0.000003
0.3600 0.000060 -0.000005 -0.075043 0.006785 0.000003
0.3800 0.000060 -0.000011 -0.074844 0.013097 0.000003
0.4000 0.000060 -0.000016 -0.074517 0.019621 0.000003
0.4200 0.000059 -0.000021 -0.074057 0.026362 0.000003
0.4400 0.000059 -0.000027 -0.073460 0.033323 0.000003
0.4600 0.000058 -0.000033 -0.072722 0.040500 0.000003
0.4800 0.000058 -0.000038 -0.071838 0.047900 0.000003
0.5000 0.000057 -0.000045 -0.070804 0.055498 0.000003
0.5200 0.000056 -0.000051 -0.069616 0.063287 0.000003
0.5400 0.000055 -0.000057 -0.068270 0.071259 0.000003
0.5600 0.000054 -0.000064 -0.066764 0.079383 0.000003
0.5800 0.000052 -0.000070 -0.065093 0.087659 0.000003
0.6000 0.000051 -0.000077 -0.063255 0.096076 0.000003
0.6200 0.000049 -0.000084 -0.061248 0.104633 0.000003
0.6400 0.000047 -0.000091 -0.059068 0.113324 0.000003
0.6600 0.000046 -0.000098 -0.056713 0.122140 0.000003
0.6800 0.000044 -0.000105 -0.054181 0.131079 0.000003
0.7000 0.000041 -0.000113 -0.051468 0.140129 0.000003
0.7200 0.000039 -0.000120 -0.048574 0.149286 0.000003
0.7400 0.000037 -0.000127 -0.045495 0.158545 0.000003
0.7600 0.000034 -0.000135 -0.042230 0.167892 0.000003
0.7800 0.000031 -0.000142 -0.038778 0.177325 0.000003
0.8000 0.000028 -0.000150 -0.035140 0.186471 0.000003
0.8200 0.000025 -0.000157 -0.031322 0.195213 0.000003
0.8400 0.000022 -0.000163 -0.027335 0.203507 0.000003
0.8600 0.000019 -0.000170 -0.023187 0.211229 0.000003
0.8800 0.000015 -0.000175 -0.018890 0.218416 0.000003
0.9000 0.000012 -0.000181 -0.014454 0.225134 0.000003
0.9200 0.000008 -0.000186 -0.009888 0.231418 0.000003
0.9400 0.000004 -0.000191 -0.005200 0.237365 0.000003
0.9600 0.000000 -0.000195 -0.000394 0.243204 0.000003
0.9800 -0.000004 -0.000200 0.004528 0.248928 0.000003
1.0000 -0.000008 -0.000204 0.009563 0.254536 0.000003
-------- Mode No. 4 (freq = 0.119534E+01 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.000000 0.000000 -0.062548 -0.074677 0.000000
0.0200 0.000000 0.000000 -0.064003 -0.070852 0.000000
0.0400 0.000000 0.000000 -0.065380 -0.066877 0.000000
0.0600 0.000000 0.000000 -0.066677 -0.062740 0.000000
0.0800 0.000000 0.000000 -0.067889 -0.058440 0.000000
0.1000 0.000000 0.000000 -0.069013 -0.053978 0.000000
0.1200 0.000000 0.000000 -0.070046 -0.049354 0.000000
0.1400 0.000000 0.000000 -0.070985 -0.044569 0.000000
0.1600 0.000000 0.000000 -0.071827 -0.039626 0.000000
0.1800 0.000000 0.000000 -0.072569 -0.034524 0.000000
0.2000 0.000000 0.000000 -0.073207 -0.029264 0.000000
0.2200 0.000000 0.000000 -0.073738 -0.023845 0.000000
0.2400 0.000000 0.000000 -0.074159 -0.018268 0.000000
0.2600 0.000000 0.000000 -0.074467 -0.012538 0.000000
0.2800 0.000000 0.000000 -0.074659 -0.006655 0.000000
0.3000 0.000000 0.000000 -0.074732 -0.000625 0.000000
0.3200 0.000000 0.000000 -0.074683 0.005552 0.000000
0.3400 0.000000 0.000000 -0.074508 0.011881 0.000000
0.3600 0.000000 0.000000 -0.074205 0.018386 0.000000
0.3800 0.000000 0.000000 -0.073771 0.025071 0.000000
0.4000 0.000000 0.000000 -0.073201 0.031929 0.000000
0.4200 0.000000 0.000000 -0.072492 0.038960 0.000000
0.4400 0.000000 0.000000 -0.071640 0.046163 0.000000
0.4600 0.000000 0.000000 -0.070643 0.053530 0.000000
0.4800 0.000000 0.000000 -0.069497 0.061064 0.000000
0.5000 0.000000 0.000000 -0.068199 0.068734 0.000000
0.5200 0.000000 0.000000 -0.066746 0.076529 0.000000
0.5400 0.000000 0.000000 -0.065136 0.084437 0.000000
0.5600 0.000000 0.000000 -0.063367 0.092419 0.000000
0.5800 0.000000 0.000000 -0.061438 0.100472 0.000000
0.6000 0.000000 0.000000 -0.059347 0.108580 0.000000
0.6200 0.000000 0.000000 -0.057093 0.116736 0.000000
0.6400 0.000000 0.000000 -0.054676 0.124928 0.000000
0.6600 0.000000 0.000000 -0.052095 0.133140 0.000000
0.6800 0.000000 0.000000 -0.049350 0.141365 0.000000
0.7000 0.000000 0.000000 -0.046440 0.149584 0.000000
0.7200 0.000000 0.000000 -0.043365 0.157785 0.000000
0.7400 0.000000 0.000000 -0.040128 0.165955 0.000000
0.7600 0.000000 0.000000 -0.036727 0.174071 0.000000
0.7800 0.000000 0.000000 -0.033164 0.182125 0.000000
0.8000 0.000000 0.000000 -0.029444 0.189791 0.000000
0.8200 0.000000 0.000000 -0.025576 0.196975 0.000000
0.8400 0.000000 0.000000 -0.021569 0.203645 0.000000
0.8600 0.000000 0.000000 -0.017435 0.209709 0.000000
0.8800 0.000000 0.000000 -0.013185 0.215211 0.000000
0.9000 0.000000 0.000000 -0.008831 0.220209 0.000000
0.9200 0.000000 0.000000 -0.004381 0.224739 0.000000
0.9400 0.000000 0.000000 0.000156 0.228880 0.000000
0.9600 0.000000 0.000000 0.004773 0.232788 0.000000
0.9800 0.000000 0.000000 0.009466 0.236454 0.000000
1.0000 0.000000 0.000000 0.014230 0.239871 0.000000
-------- Mode No. 5 (freq = 0.227418E+01 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.000000 0.000000 -0.022541 0.011866 -0.000024
0.0200 0.000000 0.000000 -0.022196 0.022614 -0.000024
0.0400 0.000000 0.000000 -0.021637 0.033121 -0.000024
0.0600 0.000000 0.000000 -0.020871 0.043401 -0.000024
0.0800 0.000000 0.000000 -0.019902 0.053433 -0.000024
0.1000 0.000000 0.000000 -0.018735 0.063188 -0.000024
0.1200 0.000000 0.000000 -0.017376 0.072641 -0.000024
0.1400 0.000000 -0.000001 -0.015831 0.081767 -0.000024
0.1600 0.000000 -0.000001 -0.014107 0.090533 -0.000024
0.1800 0.000000 -0.000001 -0.012211 0.098915 -0.000024
0.2000 0.000000 -0.000001 -0.010152 0.106883 -0.000024
0.2200 0.000000 -0.000001 -0.007938 0.114409 -0.000024
0.2400 0.000000 -0.000001 -0.005578 0.121461 -0.000024
0.2600 0.000000 -0.000001 -0.003083 0.128004 -0.000024
0.2800 0.000000 -0.000001 -0.000461 0.134005 -0.000024
0.3000 0.000000 -0.000001 0.002274 0.139427 -0.000024
0.3200 0.000000 -0.000001 0.005112 0.144235 -0.000024
0.3400 0.000000 -0.000001 0.008040 0.148397 -0.000024
0.3600 0.000000 -0.000001 0.011044 0.151888 -0.000024
0.3800 0.000000 -0.000001 0.014111 0.154661 -0.000024
0.4000 0.000000 -0.000001 0.017226 0.156666 -0.000024
0.4200 0.000000 -0.000001 0.020372 0.157849 -0.000024
0.4400 0.000000 -0.000001 0.023534 0.158156 -0.000024
0.4600 0.000000 -0.000001 0.026692 0.157529 -0.000024
0.4800 0.000000 -0.000001 0.029828 0.155908 -0.000024
0.5000 0.000000 -0.000001 0.032921 0.153237 -0.000024
0.5200 0.000000 -0.000001 0.035950 0.149461 -0.000024
0.5400 0.000000 -0.000001 0.038892 0.144523 -0.000024
0.5600 0.000000 -0.000001 0.041722 0.138386 -0.000024
0.5800 0.000000 -0.000001 0.044418 0.130991 -0.000024
0.6000 0.000000 -0.000001 0.046952 0.122286 -0.000024
0.6200 0.000000 -0.000001 0.049299 0.112211 -0.000024
0.6400 0.000000 -0.000001 0.051430 0.100703 -0.000024
0.6600 0.000000 -0.000001 0.053316 0.087708 -0.000024
0.6800 0.000000 -0.000001 0.054926 0.073150 -0.000024
0.7000 0.000000 -0.000001 0.056229 0.056971 -0.000024
0.7200 0.000000 0.000000 0.057192 0.039098 -0.000024
0.7400 0.000000 0.000000 0.057779 0.019449 -0.000024
0.7600 0.000000 0.000000 0.057955 -0.002037 -0.000024
0.7800 0.000000 0.000000 0.057682 -0.025461 -0.000024
0.8000 0.000000 0.000000 0.056930 -0.049935 -0.000024
0.8200 0.000000 0.000000 0.055682 -0.075091 -0.000024
0.8400 0.000000 0.000000 0.053925 -0.100719 -0.000024
0.8600 0.000000 0.000001 0.051657 -0.126303 -0.000024
0.8800 0.000000 0.000001 0.048877 -0.151816 -0.000024
0.9000 0.000000 0.000001 0.045587 -0.177346 -0.000024
0.9200 0.000000 0.000001 0.041785 -0.202902 -0.000024
0.9400 0.000000 0.000001 0.037470 -0.228779 -0.000024
0.9600 0.000000 0.000001 0.032624 -0.255960 -0.000024
0.9800 0.000000 0.000001 0.027220 -0.284481 -0.000024
1.0000 0.000000 0.000002 0.021233 -0.314400 -0.000024
This does not seem reasonable, so does it mean that there are still problems with the DISTRIBUTED TOWER PROPERTIES file?
Thank you in advance.
Best Regards,
Dear @Baoxuan.Wang,
From my quick review of your input files, I see a couple potential issues:
Your tower support subsystem (jacket mass and stiffness) are located at about 20 m above MSL, but your tower base is located at MSL. You should set hub_rad = 20.15 m.
I’m concerned that your tor_stff and axial_stff are several orders magnitude larger than the flap_stff and edge_stff; this will likely cause problems with BModes’ eigensolver. I would recommend using at most two orders of magnitude larger when you are trying to eliminate the torsional and axial contribution to the modes.
Best regards,
Dear Jason,
If hub_rad is the tower base height, and draft is also the depth of tower base from MSL/ground. The sign of these two varibles are opposite.
But it seems both hub_rad and draft define the same thing–I mean tower base height from MSL/ground. So I can not understand why it needs to be defined twice.
Regards
Ran
Dear @Jason.Jonkman,
This is also a question I want to ask. My understanding is that the rigid-base height for tower is usually set to 0, as mentioned in “OC3Hywind_tower_secs.dat” and the previous post file “BModes.txt”.
Best regards,
Dear @Baoxuan.Wang and @Ran.Tu,
Good point. I think I made a mistake. It seems that BModes inputs hub_rad and draft are redundant. I was thinking that they are both defined relative to MSL (with hub_rad positive upward and draft positive downward), but looking again at my OC3-Hywind model, it seems that the hub_rad is measured relative to the elevation defined by draft. Unfortunately, I can’t find good documentation for this.
Best regards,
Dear @Jason.Jonkman,
Thank you for your reply and constant assistance.
According to your advice, I modified the DISTRIBUTED TOWER PROPERTIES file again.
Tower section properties
22 n_secs: number of tower sections at which properties are specified (-)
sec_loc str_tw tw_iner mass_den flp_iner edge_iner flp_stff edge_stff tor_stff axial_stff cg_offst sc_offst tc_offst
(-) (deg) (deg) (kg/m) (kg-m) (kg-m) (Nm^2) (Nm^2) (Nm^2) (N) (m) (m) (m)
0.000 0.0 0.0 4900.472786 10 10 4.5556E+11 4.5556E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.025 0.0 0.0 4900.472786 10 10 4.4419E+11 4.4419E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.075 0.0 0.0 4200.272421 10 10 4.1707E+11 4.1707E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.125 0.0 0.0 4057.180384 10 10 3.9120E+11 3.9120E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.175 0.0 0.0 3915.575049 10 10 3.6655E+11 3.6655E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.225 0.0 0.0 3770.476234 10 10 3.4234E+11 3.4234E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.275 0.0 0.0 3626.859482 10 10 3.1932E+11 3.1932E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.325 0.0 0.0 3477.860118 10 10 2.9733E+11 2.9733E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.375 0.0 0.0 3291.027294 10 10 2.7214E+11 2.7214E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.425 0.0 0.0 3102.11339 10 10 2.4846E+11 2.4846E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.475 0.0 0.0 3123.48485 10 10 2.2622E+11 2.2622E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.525 0.0 0.0 2969.643543 10 10 2.0732E+11 2.0732E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.575 0.0 0.0 2639.437112 10 10 1.9143E+11 1.9143E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.625 0.0 0.0 2517.768961 10 10 1.7644E+11 1.7644E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.675 0.0 0.0 2398.659195 10 10 1.6232E+11 1.6232E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.725 0.0 0.0 2282.133754 10 10 1.4902E+11 1.4902E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.775 0.0 0.0 2173.8144 10 10 1.3653E+11 1.3653E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.825 0.0 0.0 2344.181633 10 10 1.4213E+11 1.4213E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.875 0.0 0.0 2687.066514 10 10 1.5659E+11 1.5659E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.925 0.0 0.0 2971.054769 10 10 1.6870E+11 1.6870E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
0.975 0.0 0.0 3260.985159 10 10 1.5955E+11 1.5955E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
1.000 0.0 0.0 3260.985159 10 10 1.5481E+11 1.5481E+11 5.0E+11 5.0E+11 0.0 0.0 0.0
**Note: If the above data represents TOWER properties, the following are overwritten:
str_tw is set to zero
tw_iner is set to zero
cg_offst is set to zero
sc_offst is set to zero
tc_offst is set to zero
edge_iner is set equal to flp_iner
edge_stff is set equal to flp_stff
and then I obtained this, which seems more right:
Results generated by BModes (v1.03.01, 25-Sept-2007, compiled using double precision) on 02-Sep-2022 at 23:29:11.
NREL 5MW OC4 Jacket Tower (Rigid foundation) WBX20220902
=================================================================================
tower frequencies & mode shapes
--- only first 20 modes printed
-------- Mode No. 1 (freq = 0.319914E+00 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 -0.015806 -0.033781 0.000000 0.000000 0.000755
0.0200 -0.016514 -0.036983 0.000000 0.000000 0.000772
0.0400 -0.017286 -0.040186 0.000000 0.000000 0.000789
0.0600 -0.018121 -0.043400 0.000000 0.000000 0.000806
0.0800 -0.019022 -0.046627 0.000000 0.000000 0.000824
0.1000 -0.019987 -0.049864 0.000000 0.000000 0.000841
0.1200 -0.021017 -0.053111 0.000000 0.000000 0.000858
0.1400 -0.022112 -0.056368 0.000000 0.000000 0.000875
0.1600 -0.023272 -0.059631 0.000000 0.000000 0.000893
0.1800 -0.024497 -0.062902 0.000000 0.000000 0.000910
0.2000 -0.025788 -0.066180 0.000000 0.000000 0.000927
0.2200 -0.027145 -0.069465 0.000000 0.000000 0.000944
0.2400 -0.028567 -0.072756 0.000000 0.000000 0.000961
0.2600 -0.030055 -0.076051 0.000000 0.000000 0.000979
0.2800 -0.031610 -0.079350 0.000000 0.000000 0.000996
0.3000 -0.033230 -0.082651 0.000000 0.000000 0.001013
0.3200 -0.034916 -0.085952 0.000000 0.000000 0.001030
0.3400 -0.036668 -0.089257 0.000000 0.000000 0.001048
0.3600 -0.038487 -0.092578 0.000000 0.000000 0.001065
0.3800 -0.040372 -0.095917 0.000000 0.000000 0.001082
0.4000 -0.042324 -0.099269 0.000000 0.000000 0.001099
0.4200 -0.044343 -0.102635 0.000000 0.000000 0.001117
0.4400 -0.046430 -0.106013 0.000000 0.000000 0.001134
0.4600 -0.048584 -0.109398 0.000000 0.000000 0.001151
0.4800 -0.050806 -0.112792 0.000000 0.000000 0.001168
0.5000 -0.053096 -0.116180 0.000000 0.000000 0.001185
0.5200 -0.055454 -0.119557 0.000000 0.000000 0.001203
0.5400 -0.057879 -0.122918 0.000000 0.000000 0.001220
0.5600 -0.060371 -0.126248 0.000000 0.000000 0.001237
0.5800 -0.062929 -0.129544 0.000000 0.000000 0.001254
0.6000 -0.065552 -0.132800 0.000000 0.000000 0.001272
0.6200 -0.068241 -0.136013 0.000000 0.000000 0.001289
0.6400 -0.070993 -0.139179 0.000000 0.000000 0.001306
0.6600 -0.073808 -0.142290 0.000000 0.000000 0.001323
0.6800 -0.076684 -0.145344 0.000000 0.000000 0.001340
0.7000 -0.079622 -0.148332 0.000000 0.000000 0.001358
0.7200 -0.082618 -0.151249 0.000000 0.000000 0.001375
0.7400 -0.085671 -0.154089 0.000000 0.000000 0.001392
0.7600 -0.088781 -0.156843 0.000000 0.000000 0.001409
0.7800 -0.091945 -0.159506 0.000000 0.000000 0.001427
0.8000 -0.095160 -0.161971 0.000000 0.000000 0.001444
0.8200 -0.098422 -0.164211 0.000000 0.000000 0.001461
0.8400 -0.101727 -0.166222 0.000000 0.000000 0.001478
0.8600 -0.105069 -0.167982 0.000000 0.000000 0.001496
0.8800 -0.108444 -0.169512 0.000000 0.000000 0.001513
0.9000 -0.111848 -0.170835 0.000000 0.000000 0.001530
0.9200 -0.115276 -0.171966 0.000000 0.000000 0.001547
0.9400 -0.118725 -0.172931 0.000000 0.000000 0.001564
0.9600 -0.122193 -0.173767 0.000000 0.000000 0.001582
0.9800 -0.125675 -0.174469 0.000000 0.000000 0.001599
1.0000 -0.129170 -0.175034 0.000000 0.000000 0.001616
-------- Mode No. 2 (freq = 0.322715E+00 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.000000 0.000000 -0.016010 -0.034140 0.000000
0.0200 0.000000 0.000000 -0.016725 -0.037359 0.000000
0.0400 0.000000 0.000000 -0.017505 -0.040579 0.000000
0.0600 0.000000 0.000000 -0.018349 -0.043809 0.000000
0.0800 0.000000 0.000000 -0.019257 -0.047051 0.000000
0.1000 0.000000 0.000000 -0.020231 -0.050302 0.000000
0.1200 0.000000 0.000000 -0.021270 -0.053562 0.000000
0.1400 0.000000 0.000000 -0.022374 -0.056829 0.000000
0.1600 0.000000 0.000000 -0.023543 -0.060103 0.000000
0.1800 0.000000 0.000000 -0.024778 -0.063383 0.000000
0.2000 0.000000 0.000000 -0.026079 -0.066668 0.000000
0.2200 0.000000 0.000000 -0.027445 -0.069959 0.000000
0.2400 0.000000 0.000000 -0.028878 -0.073256 0.000000
0.2600 0.000000 0.000000 -0.030376 -0.076554 0.000000
0.2800 0.000000 0.000000 -0.031940 -0.079854 0.000000
0.3000 0.000000 0.000000 -0.033570 -0.083154 0.000000
0.3200 0.000000 0.000000 -0.035267 -0.086453 0.000000
0.3400 0.000000 0.000000 -0.037029 -0.089753 0.000000
0.3600 0.000000 0.000000 -0.038857 -0.093068 0.000000
0.3800 0.000000 0.000000 -0.040752 -0.096398 0.000000
0.4000 0.000000 0.000000 -0.042714 -0.099740 0.000000
0.4200 0.000000 0.000000 -0.044742 -0.103091 0.000000
0.4400 0.000000 0.000000 -0.046838 -0.106453 0.000000
0.4600 0.000000 0.000000 -0.049001 -0.109818 0.000000
0.4800 0.000000 0.000000 -0.051231 -0.113190 0.000000
0.5000 0.000000 0.000000 -0.053529 -0.116552 0.000000
0.5200 0.000000 0.000000 -0.055893 -0.119900 0.000000
0.5400 0.000000 0.000000 -0.058325 -0.123228 0.000000
0.5600 0.000000 0.000000 -0.060823 -0.126521 0.000000
0.5800 0.000000 0.000000 -0.063386 -0.129776 0.000000
0.6000 0.000000 0.000000 -0.066014 -0.132988 0.000000
0.6200 0.000000 0.000000 -0.068705 -0.136152 0.000000
0.6400 0.000000 0.000000 -0.071460 -0.139263 0.000000
0.6600 0.000000 0.000000 -0.074276 -0.142316 0.000000
0.6800 0.000000 0.000000 -0.077152 -0.145306 0.000000
0.7000 0.000000 0.000000 -0.080088 -0.148224 0.000000
0.7200 0.000000 0.000000 -0.083081 -0.151066 0.000000
0.7400 0.000000 0.000000 -0.086130 -0.153825 0.000000
0.7600 0.000000 0.000000 -0.089234 -0.156492 0.000000
0.7800 0.000000 0.000000 -0.092390 -0.159061 0.000000
0.8000 0.000000 0.000000 -0.095595 -0.161428 0.000000
0.8200 0.000000 0.000000 -0.098845 -0.163568 0.000000
0.8400 0.000000 0.000000 -0.102136 -0.165478 0.000000
0.8600 0.000000 0.000000 -0.105462 -0.167138 0.000000
0.8800 0.000000 0.000000 -0.108820 -0.168568 0.000000
0.9000 0.000000 0.000000 -0.112204 -0.169791 0.000000
0.9200 0.000000 0.000000 -0.115610 -0.170823 0.000000
0.9400 0.000000 0.000000 -0.119035 -0.171687 0.000000
0.9600 0.000000 0.000000 -0.122477 -0.172417 0.000000
0.9800 0.000000 0.000000 -0.125931 -0.173009 0.000000
1.0000 0.000000 0.000000 -0.129396 -0.173457 0.000000
-------- Mode No. 3 (freq = 0.115832E+01 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 -0.060838 -0.075116 0.000000 0.000000 -0.005031
0.0200 -0.062310 -0.072033 0.000000 0.000000 -0.005135
0.0400 -0.063718 -0.068792 0.000000 0.000000 -0.005240
0.0600 -0.065060 -0.065382 0.000000 0.000000 -0.005344
0.0800 -0.066332 -0.061800 0.000000 0.000000 -0.005448
0.1000 -0.067531 -0.058047 0.000000 0.000000 -0.005552
0.1200 -0.068653 -0.054122 0.000000 0.000000 -0.005656
0.1400 -0.069694 -0.050022 0.000000 0.000000 -0.005760
0.1600 -0.070652 -0.045751 0.000000 0.000000 -0.005865
0.1800 -0.071523 -0.041304 0.000000 0.000000 -0.005969
0.2000 -0.072303 -0.036682 0.000000 0.000000 -0.006073
0.2200 -0.072988 -0.031882 0.000000 0.000000 -0.006177
0.2400 -0.073576 -0.026904 0.000000 0.000000 -0.006281
0.2600 -0.074063 -0.021749 0.000000 0.000000 -0.006385
0.2800 -0.074444 -0.016417 0.000000 0.000000 -0.006490
0.3000 -0.074718 -0.010909 0.000000 0.000000 -0.006594
0.3200 -0.074879 -0.005226 0.000000 0.000000 -0.006698
0.3400 -0.074925 0.000643 0.000000 0.000000 -0.006802
0.3600 -0.074851 0.006719 0.000000 0.000000 -0.006906
0.3800 -0.074654 0.013012 0.000000 0.000000 -0.007011
0.4000 -0.074329 0.019516 0.000000 0.000000 -0.007115
0.4200 -0.073871 0.026236 0.000000 0.000000 -0.007219
0.4400 -0.073277 0.033176 0.000000 0.000000 -0.007323
0.4600 -0.072542 0.040331 0.000000 0.000000 -0.007427
0.4800 -0.071661 0.047709 0.000000 0.000000 -0.007531
0.5000 -0.070631 0.055284 0.000000 0.000000 -0.007636
0.5200 -0.069448 0.063050 0.000000 0.000000 -0.007740
0.5400 -0.068107 0.070998 0.000000 0.000000 -0.007844
0.5600 -0.066606 0.079098 0.000000 0.000000 -0.007948
0.5800 -0.064941 0.087349 0.000000 0.000000 -0.008052
0.6000 -0.063110 0.095741 0.000000 0.000000 -0.008157
0.6200 -0.061110 0.104272 0.000000 0.000000 -0.008261
0.6400 -0.058937 0.112938 0.000000 0.000000 -0.008365
0.6600 -0.056591 0.121727 0.000000 0.000000 -0.008469
0.6800 -0.054067 0.130640 0.000000 0.000000 -0.008573
0.7000 -0.051363 0.139663 0.000000 0.000000 -0.008677
0.7200 -0.048478 0.148793 0.000000 0.000000 -0.008782
0.7400 -0.045410 0.158025 0.000000 0.000000 -0.008886
0.7600 -0.042156 0.167343 0.000000 0.000000 -0.008990
0.7800 -0.038714 0.176749 0.000000 0.000000 -0.009094
0.8000 -0.035088 0.185868 0.000000 0.000000 -0.009198
0.8200 -0.031283 0.194584 0.000000 0.000000 -0.009302
0.8400 -0.027308 0.202854 0.000000 0.000000 -0.009407
0.8600 -0.023173 0.210552 0.000000 0.000000 -0.009511
0.8800 -0.018890 0.217718 0.000000 0.000000 -0.009615
0.9000 -0.014469 0.224417 0.000000 0.000000 -0.009719
0.9200 -0.009917 0.230682 0.000000 0.000000 -0.009823
0.9400 -0.005244 0.236611 0.000000 0.000000 -0.009928
0.9600 -0.000453 0.242432 0.000000 0.000000 -0.010032
0.9800 0.004453 0.248139 0.000000 0.000000 -0.010136
1.0000 0.009472 0.253731 0.000000 0.000000 -0.010240
-------- Mode No. 4 (freq = 0.119523E+01 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.000000 0.000000 -0.062543 -0.074679 0.000000
0.0200 0.000000 0.000000 -0.063999 -0.070856 0.000000
0.0400 0.000000 0.000000 -0.065376 -0.066883 0.000000
0.0600 0.000000 0.000000 -0.066672 -0.062748 0.000000
0.0800 0.000000 0.000000 -0.067885 -0.058450 0.000000
0.1000 0.000000 0.000000 -0.069009 -0.053990 0.000000
0.1200 0.000000 0.000000 -0.070043 -0.049369 0.000000
0.1400 0.000000 0.000000 -0.070982 -0.044586 0.000000
0.1600 0.000000 0.000000 -0.071825 -0.039645 0.000000
0.1800 0.000000 0.000000 -0.072567 -0.034544 0.000000
0.2000 0.000000 0.000000 -0.073205 -0.029286 0.000000
0.2200 0.000000 0.000000 -0.073736 -0.023868 0.000000
0.2400 0.000000 0.000000 -0.074158 -0.018293 0.000000
0.2600 0.000000 0.000000 -0.074467 -0.012565 0.000000
0.2800 0.000000 0.000000 -0.074659 -0.006684 0.000000
0.3000 0.000000 0.000000 -0.074732 -0.000655 0.000000
0.3200 0.000000 0.000000 -0.074684 0.005521 0.000000
0.3400 0.000000 0.000000 -0.074510 0.011849 0.000000
0.3600 0.000000 0.000000 -0.074208 0.018353 0.000000
0.3800 0.000000 0.000000 -0.073774 0.025036 0.000000
0.4000 0.000000 0.000000 -0.073204 0.031893 0.000000
0.4200 0.000000 0.000000 -0.072496 0.038923 0.000000
0.4400 0.000000 0.000000 -0.071646 0.046125 0.000000
0.4600 0.000000 0.000000 -0.070649 0.053492 0.000000
0.4800 0.000000 0.000000 -0.069504 0.061026 0.000000
0.5000 0.000000 0.000000 -0.068206 0.068696 0.000000
0.5200 0.000000 0.000000 -0.066754 0.076491 0.000000
0.5400 0.000000 0.000000 -0.065145 0.084399 0.000000
0.5600 0.000000 0.000000 -0.063377 0.092381 0.000000
0.5800 0.000000 0.000000 -0.061448 0.100435 0.000000
0.6000 0.000000 0.000000 -0.059358 0.108545 0.000000
0.6200 0.000000 0.000000 -0.057105 0.116701 0.000000
0.6400 0.000000 0.000000 -0.054689 0.124895 0.000000
0.6600 0.000000 0.000000 -0.052109 0.133109 0.000000
0.6800 0.000000 0.000000 -0.049364 0.141336 0.000000
0.7000 0.000000 0.000000 -0.046454 0.149558 0.000000
0.7200 0.000000 0.000000 -0.043381 0.157761 0.000000
0.7400 0.000000 0.000000 -0.040143 0.165935 0.000000
0.7600 0.000000 0.000000 -0.036743 0.174055 0.000000
0.7800 0.000000 0.000000 -0.033180 0.182112 0.000000
0.8000 0.000000 0.000000 -0.029461 0.189783 0.000000
0.8200 0.000000 0.000000 -0.025593 0.196971 0.000000
0.8400 0.000000 0.000000 -0.021586 0.203646 0.000000
0.8600 0.000000 0.000000 -0.017452 0.209716 0.000000
0.8800 0.000000 0.000000 -0.013202 0.215222 0.000000
0.9000 0.000000 0.000000 -0.008847 0.220225 0.000000
0.9200 0.000000 0.000000 -0.004396 0.224761 0.000000
0.9400 0.000000 0.000000 0.000141 0.228907 0.000000
0.9600 0.000000 0.000000 0.004759 0.232821 0.000000
0.9800 0.000000 0.000000 0.009452 0.236493 0.000000
1.0000 0.000000 0.000000 0.014217 0.239916 0.000000
-------- Mode No. 5 (freq = 0.184094E+01 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 -0.000332 -0.000073 0.000000 0.000000 0.068533
0.0200 -0.000332 0.000029 0.000000 0.000000 0.069712
0.0400 -0.000331 0.000131 0.000000 0.000000 0.070890
0.0600 -0.000327 0.000231 0.000000 0.000000 0.072069
0.0800 -0.000321 0.000331 0.000000 0.000000 0.073248
0.1000 -0.000314 0.000430 0.000000 0.000000 0.074427
0.1200 -0.000304 0.000527 0.000000 0.000000 0.075606
0.1400 -0.000293 0.000624 0.000000 0.000000 0.076785
0.1600 -0.000279 0.000719 0.000000 0.000000 0.077963
0.1800 -0.000264 0.000812 0.000000 0.000000 0.079142
0.2000 -0.000247 0.000904 0.000000 0.000000 0.080321
0.2200 -0.000228 0.000993 0.000000 0.000000 0.081500
0.2400 -0.000207 0.001080 0.000000 0.000000 0.082679
0.2600 -0.000185 0.001165 0.000000 0.000000 0.083858
0.2800 -0.000160 0.001247 0.000000 0.000000 0.085036
0.3000 -0.000135 0.001326 0.000000 0.000000 0.086215
0.3200 -0.000107 0.001401 0.000000 0.000000 0.087394
0.3400 -0.000079 0.001474 0.000000 0.000000 0.088573
0.3600 -0.000048 0.001542 0.000000 0.000000 0.089752
0.3800 -0.000017 0.001608 0.000000 0.000000 0.090930
0.4000 0.000016 0.001669 0.000000 0.000000 0.092109
0.4200 0.000050 0.001726 0.000000 0.000000 0.093288
0.4400 0.000085 0.001778 0.000000 0.000000 0.094467
0.4600 0.000121 0.001825 0.000000 0.000000 0.095646
0.4800 0.000158 0.001866 0.000000 0.000000 0.096825
0.5000 0.000195 0.001901 0.000000 0.000000 0.098003
0.5200 0.000234 0.001930 0.000000 0.000000 0.099182
0.5400 0.000273 0.001951 0.000000 0.000000 0.100361
0.5600 0.000312 0.001965 0.000000 0.000000 0.101540
0.5800 0.000351 0.001971 0.000000 0.000000 0.102719
0.6000 0.000391 0.001969 0.000000 0.000000 0.103897
0.6200 0.000430 0.001958 0.000000 0.000000 0.105076
0.6400 0.000469 0.001938 0.000000 0.000000 0.106255
0.6600 0.000507 0.001908 0.000000 0.000000 0.107434
0.6800 0.000545 0.001868 0.000000 0.000000 0.108613
0.7000 0.000582 0.001818 0.000000 0.000000 0.109791
0.7200 0.000618 0.001756 0.000000 0.000000 0.110970
0.7400 0.000652 0.001682 0.000000 0.000000 0.112149
0.7600 0.000685 0.001597 0.000000 0.000000 0.113328
0.7800 0.000716 0.001498 0.000000 0.000000 0.114507
0.8000 0.000745 0.001391 0.000000 0.000000 0.115685
0.8200 0.000771 0.001276 0.000000 0.000000 0.116864
0.8400 0.000796 0.001155 0.000000 0.000000 0.118043
0.8600 0.000818 0.001031 0.000000 0.000000 0.119222
0.8800 0.000837 0.000904 0.000000 0.000000 0.120401
0.9000 0.000854 0.000774 0.000000 0.000000 0.121579
0.9200 0.000868 0.000642 0.000000 0.000000 0.122758
0.9400 0.000879 0.000507 0.000000 0.000000 0.123937
0.9600 0.000888 0.000362 0.000000 0.000000 0.125116
0.9800 0.000894 0.000209 0.000000 0.000000 0.126295
1.0000 0.000896 0.000048 0.000000 0.000000 0.127473
-------- Mode No. 6 (freq = 0.246167E+01 Hz)
span_loc s-s disp s-s slope f-a disp f-a slope twist
0.0000 0.017830 -0.016981 0.000000 0.000000 0.013310
0.0200 0.017387 -0.027204 0.000000 0.000000 0.013478
0.0400 0.016742 -0.037166 0.000000 0.000000 0.013646
0.0600 0.015901 -0.046878 0.000000 0.000000 0.013814
0.0800 0.014868 -0.056320 0.000000 0.000000 0.013982
0.1000 0.013650 -0.065463 0.000000 0.000000 0.014150
0.1200 0.012251 -0.074282 0.000000 0.000000 0.014319
0.1400 0.010680 -0.082752 0.000000 0.000000 0.014487
0.1600 0.008943 -0.090841 0.000000 0.000000 0.014655
0.1800 0.007048 -0.098524 0.000000 0.000000 0.014823
0.2000 0.005004 -0.105772 0.000000 0.000000 0.014991
0.2200 0.002820 -0.112559 0.000000 0.000000 0.015159
0.2400 0.000505 -0.118853 0.000000 0.000000 0.015327
0.2600 -0.001931 -0.124619 0.000000 0.000000 0.015495
0.2800 -0.004477 -0.129827 0.000000 0.000000 0.015663
0.3000 -0.007121 -0.134441 0.000000 0.000000 0.015831
0.3200 -0.009851 -0.138429 0.000000 0.000000 0.015999
0.3400 -0.012654 -0.141759 0.000000 0.000000 0.016167
0.3600 -0.015517 -0.144406 0.000000 0.000000 0.016335
0.3800 -0.018426 -0.146325 0.000000 0.000000 0.016504
0.4000 -0.021365 -0.147468 0.000000 0.000000 0.016672
0.4200 -0.024319 -0.147787 0.000000 0.000000 0.016840
0.4400 -0.027271 -0.147230 0.000000 0.000000 0.017008
0.4600 -0.030202 -0.145746 0.000000 0.000000 0.017176
0.4800 -0.033094 -0.143277 0.000000 0.000000 0.017344
0.5000 -0.035926 -0.139779 0.000000 0.000000 0.017512
0.5200 -0.038677 -0.135203 0.000000 0.000000 0.017680
0.5400 -0.041326 -0.129500 0.000000 0.000000 0.017848
0.5600 -0.043849 -0.122643 0.000000 0.000000 0.018016
0.5800 -0.046223 -0.114581 0.000000 0.000000 0.018184
0.6000 -0.048423 -0.105272 0.000000 0.000000 0.018352
0.6200 -0.050424 -0.094666 0.000000 0.000000 0.018520
0.6400 -0.052199 -0.082708 0.000000 0.000000 0.018688
0.6600 -0.053722 -0.069357 0.000000 0.000000 0.018856
0.6800 -0.054962 -0.054548 0.000000 0.000000 0.019025
0.7000 -0.055892 -0.038238 0.000000 0.000000 0.019193
0.7200 -0.056479 -0.020363 0.000000 0.000000 0.019361
0.7400 -0.056693 -0.000859 0.000000 0.000000 0.019529
0.7600 -0.056500 0.020322 0.000000 0.000000 0.019697
0.7800 -0.055866 0.043263 0.000000 0.000000 0.019865
0.8000 -0.054764 0.067085 0.000000 0.000000 0.020033
0.8200 -0.053180 0.091429 0.000000 0.000000 0.020201
0.8400 -0.051107 0.116090 0.000000 0.000000 0.020369
0.8600 -0.048541 0.140575 0.000000 0.000000 0.020537
0.8800 -0.045488 0.164866 0.000000 0.000000 0.020705
0.9000 -0.041950 0.189050 0.000000 0.000000 0.020873
0.9200 -0.037929 0.213138 0.000000 0.000000 0.021041
0.9400 -0.033424 0.237411 0.000000 0.000000 0.021209
0.9600 -0.028423 0.262788 0.000000 0.000000 0.021377
0.9800 -0.022903 0.289293 0.000000 0.000000 0.021546
1.0000 -0.016842 0.316976 0.000000 0.000000 0.021714
For convenience of comparison, I copy and attach the OC4 results from NREL/CP-5000-54124 and modes obtained by me here:
Running BModes (v1.03.01, 25-Sept-2007, compiled using double precision).
Linked with the NWTC Subroutine Library (v1.01.08, 26-Sep-2007).
all parameters checked : o.k.
******** modal analysis results **********
eigenvalue( 1) =0.368443D+11 mode 1 frequency = 0.319914 （1st side-side）
eigenvalue( 2) =0.374922D+11 mode 2 frequency = 0.322715 （1st fore-aft）
eigenvalue( 3) =0.483012D+12 mode 3 frequency = 1.158318 （2st side-side）
eigenvalue( 4) =0.514288D+12 mode 4 frequency = 1.195232 （2st fore-aft）
eigenvalue( 5) =0.122006D+13 mode 5 frequency = 1.840942 （1st twist）
eigenvalue( 6) =0.218153D+13 mode 6 frequency = 2.461666
eigenvalue( 7) =0.319175D+13 mode 7 frequency = 2.977577
eigenvalue( 8) =0.104610D+14 mode 8 frequency = 5.390582
eigenvalue( 9) =0.123930D+14 mode 9 frequency = 5.867289
eigenvalue(10) =0.162585D+14 mode 10 frequency = 6.720311
eigenvalue(11) =0.180712D+14 mode 11 frequency = 7.085043
eigenvalue(12) =0.564525D+14 mode 12 frequency = 12.522482
eigenvalue(13) =0.576709D+14 mode 13 frequency = 12.656890
eigenvalue(14) =0.166495D+15 mode 14 frequency = 21.505512
eigenvalue(15) =0.168955D+15 mode 15 frequency = 21.663798
eigenvalue(16) =0.253024D+15 mode 16 frequency = 26.511195
eigenvalue(17) =0.523198D+15 mode 17 frequency = 38.122539
eigenvalue(18) =0.526391D+15 mode 18 frequency = 38.238703
eigenvalue(19) =0.135523D+16 mode 19 frequency = 61.355765
eigenvalue(20) =0.135901D+16 mode 20 frequency = 61.441261
Do you think this results (including distinguished tower modes ) are reasonable and correct? Thank you!
Best Regards,