Journal of Theoretical
and Applied Mechanics

57, 1, pp. 85-97, Warsaw 2019
DOI: 10.15632/jtam-pl.57.1.85

Numerical and experimental analysis of a segmented wind turbine blade under assembling load effects

Majdi Yangui, Slim Bouaziz, Mohamed Taktak, Vincent Debut, J. Antunes, Mohamed Haddar
In this paper, numerical and experimental modal analysis of a segmented wind turbine blade
assembled with a steel threaded shaft and a nut are presented. The blade segments are built
by a 3D printer using ABS material. The experimental modal parameters identification has
been achieved using the Eigen system Realization Algorithm (ERA) method for different values
of the blade segments assembly force caused by the nut tightening torque. Furthermore,
a three dimensional finite element model has been built using DTK18 three node triangular
shell elements in order to model the blade and the threaded shaft structure, taking into
account the additional stiffness caused by the nut tightening torque. This study covers the
blade segments assembly force effects on the rotating blade vibration characteristics. The
numerical model is adjusted and validated by the identified experimental results. This work
highlights the significant variation of the natural frequencies of the segmented wind turbine
blade by the assembling load of the segments versus blade rotating speed.
Keywords: segmented wind turbine blade, experimental modal analysis, shell element modeling, assembling load


Abdulaziz A.H., Elsabbagh A.M., Akl W.N., 2015, Dynamic and static characterization of

horizontal axis wind turbine blades using dimensionless analysis of scaled-down models, International

Journal of Renewable Energy Research (IJRER), 5, 2, 404-418

Bayoumy A.H., Nada A.A., Megahed S.M., 2013, A continuum based three-dimensional modeling

of wind turbine blades, Journal of Computational and Nonlinear Dynamics, 8, 3, 031004

Bhat C., Noronha D.J., Saldanha F.A., 2015a, Structural performance evaluation of modularized

wind turbine blade through finite element simulation, International Journal of Mechanical,

Aerospace, Industrial, Mechatronic and Manufacturing Engineering, 9, 6, 930-942

Bhat C., Noronha D.J., Saldanha F.A., 2015b, Structural performance evaluation of segmented

wind turbine blade through finite element simulation, International Journal of Mechanical,

Aerospace, Industrial, Mechatronic and Manufacturing Engineering, 9, 6, 996-1005

Branner K., Berring P., Berggreen C., Knudsen H.W., 2007, Torsional performance of

wind turbine blades – Part II: Numerical validation, International Conference on Composite Materials


Broehl J., 2014, Wind Energy Innovations: Segmented Blades,

Dhar S., 2006, Development and validation of small-scale model to predict large wind turbine

behavior, Doctoral dissertation, Indian Institute of Technology, Bombay

Griffith D.T., 2009, Structural dynamics analysis and model validation of wind turbine structures, 50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference 17th AIAA/ASME/AHS Adaptive Structures Conference 11th AIAA, p. 2408

Ha N.S., Vang H.M., Goo N.S., 2015, Modal analysis using digital image correlation technique:

An application to artificial wing mimicking beetles hind wing, Experimental Mechanics, 55, 5, 989-998

Hamdi H., Mrad C., Hamdi A., Nasri R., 2014, Dynamic response of a horizontal axis wind

turbine blade under aerodynamic, gravity and gyroscopic effects, Applied Acoustics, 86, 154-164

Kang H., Chang C., Saberi H., Ormiston R.A., 2014, Assessment of beam and shell elements

for modeling rotorcraft blades, Journal of Aircraft, 51, 2, 520-531

Kim S.W., Kim E.H., Rim M.S., Shrestha P., Lee I., Kwon I.B., 2011, Structural performance

tests of down scaled composite wind turbine blade using embedded fiber Bragg grating sensors,

International Journal Aeronautical and Space Sciences, 12, 4, 346-353

Larsen G.C., Hansen M.H., Baumgart A., Carl´en I., 2002, Modal Analysis of Wind Turbine

Blades, Riso National Laboratory, Denmark

Maalawi K.Y., Negm H.M., 2002, Optimal frequency design of wind turbine blades, Journal of

Wind Engineering and Industrial Aerodynamics, 90, 8, 961-986

McKittrick L.R., Cairns D.S., Mandell J., Combs D.C., Rabern D.A., Van Luchene

R.D., 2001, Analysis of a composite blade design for the AOC 15/50 wind turbine using a finite

element model, Sandia National Laboratories Report

Molenaar D.P., 2003, Experimental modal analysis of a 750 kW wind turbine for structural model

validation. ASME 2003 Wind Energy Symposium, American Society of Mechanical Engineers, 322-339

Park J.H., Park H.Y., Jeong S.Y., Lee S.I., Shin Y.H., Park J.P., 2010, Linear vibration

analysis of rotating wind-turbine blade, Current Applied Physics, 10, 2, S332-S334

Saldanha F.A., Rao V.V., Christopher J., Adhikari R., 2013, Investigations on concepts

for modularizing a horizontal axis wind turbine blade, ASME 2013 International Design Engineering

Technical Conferences and Computers and Information in Engineering Conference, pp.

V008T12A003-V008T12A003, American Society of Mechanical Engineers

Sami S., Zai B.A., Khan M.A., 2014, Dynamic analysis of a 5KW wind turbine blade with

experimental validation, Journal of Space Technology, 4, 1, 82-87

Sheibani M., Akbari A.A., 2015, Finite element modeling of a wind turbine blade, Journal of

Vibroengineering, 17, 7

Tartibu L.K., Kilfoil M., Van Der Merwe A.J., 2012, Vibration analysis of a variable length

blade wind turbine, International Journal of Advances in Engineering and Technology, 4, 1, 630-639

Yangui M., Bouaziz S., Taktak M., Haddar M., El-Sabbagh A., 2016, Nonlinear analysis

of twisted wind turbine blade, Journal of Mechanics, doi:10.1017/jmech.2016.120, 1-10