Experimental and Numerical Comparison of Impact Behavior between Thermoplastic and Thermoset Composite for Wind Turbine Blades

Damage generated due to low velocity impact in composite plates was evaluated focusing on the design and structural integrity of wind turbine blades. Impact properties of composite plates manufactured with thermoplastic and thermoset resins for different energy levels were measured and compared. Specimens were fabricated using VARTM (vacuum assisted resin transfer molding), using both matrix systems in conjunction with carbon, glass and carbon/glass hybrid fibers in the NCF (non-crimp fabric) architecture. Resin systems used were ELIUM 188O (thermoplastic) from Arkema Co., Ltd. and a standard epoxy reference, EPR-L20 from Hexion Co., Ltd. (thermoset). Auxiliary numerical finite element analyses were performed to better understand the tests physics. These models were then compared with the experimental results to verify their predictive capacity, given the intrinsic limitations due to their simplicity. Based in the presented results, it is possible to observe that ELIUM is capable to replace a conventional thermoset matrix. The thermoplastic panels presented similar results compared to its thermoset counterparts, with even a trend of less impact damage. Additionally, for both thermoplastic and thermoset resin systems, glass layups showed the lowest levels of damage while carbon panels presented the highest damage levels. Hybrid laminates can be applied as a compromise solution.

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Review of Icing Effects on Wind Turbine in Cold Regions

E3S Web of Conferences ◽

10.1051/e3sconf/20187201007 ◽

2018 ◽

Vol 72 ◽

pp. 01007 ◽

Cited By ~ 2

Author(s):

Faizan Afzal ◽

Muhammad S. Virk

Keyword(s):

Wind Turbine ◽

Structural Integrity ◽

Turbine Blades ◽

Leading Edge ◽

Added Mass ◽

Cold Climate ◽

Ice Accretion ◽

Wind Turbine Blades ◽

Turbine Performance ◽

Ice Shedding

This paper describes a brief overview of main issues related to atmospheric ice accretion on wind turbines installed in cold climate region. Icing has significant effects on wind turbine performance particularly from aerodynamic and structural integrity perspective, as ice accumulates mainly on the leading edge of the blades that change its aerodynamic profile shape and effects its structural dynamics due to added mass effects of ice. This research aims to provide an overview and develop further understanding of the effects of atmospheric ice accretion on wind turbine blades. One of the operational challenges of the wind turbine blade operation in icing condition is also to overcome the process of ice shedding, which may happen due to vibrations or bending of the blades. Ice shedding is dangerous phenomenon, hazardous for equipment and personnel in the immediate area.

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Acoustic Emission for Structural Integrity Assessment of Wind Turbine Blades

Springer Proceedings in Physics - Advances in Acoustic Emission Technology ◽

10.1007/978-1-4939-1239-1_34 ◽

2014 ◽

pp. 369-382 ◽

Cited By ~ 1

Author(s):

Nikolaos K. Tsopelas ◽

Dimitrios G. Papasalouros ◽

Athanasios A. Anastasopoulos ◽

Dimitrios A. Kourousis ◽

Jason W. Dong

Keyword(s):

Acoustic Emission ◽

Wind Turbine ◽

Structural Integrity ◽

Turbine Blades ◽

Wind Turbine Blades ◽

Integrity Assessment

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Experimental Validation of the Structural Integrity of Modular Horizontal Axis Wind Turbine Blades

Proceedings ◽

10.3390/proceedings1070694 ◽

2017 ◽

Vol 1 (7) ◽

pp. 694

Author(s):

Abhishek Asthana ◽

Sanjay Mukherjee ◽

Sara Mountney ◽

Ryan Griffiths

Keyword(s):

Wind Turbine ◽

Experimental Validation ◽

Structural Integrity ◽

Turbine Blades ◽

Horizontal Axis ◽

Wind Turbine Blades ◽

Horizontal Axis Wind Turbine

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Development of a Dual-Axis Phase-Locked Excitation (PhLEX) Resonant Fatigue Test Method for Wind Turbine Blades

Volume 6B: Energy ◽

10.1115/imece2013-65065 ◽

2013 ◽

Author(s):

Jenna A. Beckwith ◽

Darris White ◽

Domenic L. Barsotti

Keyword(s):

Wind Turbine ◽

Fatigue Test ◽

Structural Integrity ◽

Fatigue Testing ◽

Turbine Blades ◽

Test Method ◽

Wind Loading ◽

Testing Time ◽

Wind Turbine Blades ◽

Operation Conditions

Collaborative efforts between Embry-Riddle Aeronautical University (ERAU) and the National Renewable Energy Laboratory (NREL) have resulted in an innovative dual-axis Phase-Locked EXcitation (PhLEX) resonant test method for structural fatigue testing of wind turbine blades. Laboratory fatigue test results give blade manufacturers important information regarding the structural integrity of their designs and can offer insight on how to further increase the strength and efficiency of these blades. The PhLEX test method applies loads in a manner that is more representative of wind loading experienced through field operation conditions as compared to current dual-axis quantum resonant methods. The method developed involves exciting the blade at resonance in the edge direction, while simultaneously applying a direct actuation force in the flap direction at the first edge frequency. As a proof of concept, this method was employed on a 9-meter (m) blade test article at NREL’s National Wind Technology Center (NWTC) located near Boulder, Colorado. Preliminary results show that the PhLEX method is able to control the phase angle between application of flap and edge loads while decreasing testing time due to faster test frequencies and the ability to maintain constant amplitude loading.

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Identification of Debonding Damage at Spar Cap-Shear Web Joints by Artificial Neural Network Using Natural Frequency Relevant Key Features of Composite Wind Turbine Blades

Applied Sciences ◽

10.3390/app11125327 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5327

Author(s):

Yun-Jung Jang ◽

Hyeong-Jin Kim ◽

Hak-Geun Kim ◽

Ki-Weon Kang

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Wind Turbine ◽

Natural Frequency ◽

Structural Integrity ◽

Natural Frequencies ◽

Turbine Blades ◽

Wind Turbine Blades ◽

Artificial Neural ◽

The Relationship

As the size and weight of blades increase with the recent trend toward larger wind turbines, it is important to ensure the structural integrity of the blades. For this reason, the blade consists of an upper and lower skin that receives the load directly, a shear web that supports the two skins, and a spar cap that connects the skin and the shear web. Loads generated during the operation of the wind turbine can cause debonding damage on the spar cap-shear web joints. This may change the structural stiffness of the blade and lead to a lack of integrity; therefore, it would be beneficial to be able to identify possible damage in advance. In this paper we present a model to identify debonding damage based on natural frequency. This was carried out by modeling 1105 different debonding damages, which were classified by configuration type, location, and length. After that, the natural frequencies, due to the debonding damage of the blades, were obtained through modal analysis using FE analysis. Finally, an artificial neural network was used to study the relationship between debonding damage and the natural frequencies.

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Structural analysis of offshore wind turbine blades using finite element method

Wind Engineering ◽

10.1177/0309524x19849830 ◽

2019 ◽

Vol 44 (2) ◽

pp. 168-180 ◽

Cited By ~ 1

Author(s):

Hicham Boudounit ◽

Mostapha Tarfaoui ◽

Dennoun Saifaoui ◽

Mourad Nachtane

Keyword(s):

Finite Element ◽

Wind Energy ◽

Wind Turbine ◽

Structural Integrity ◽

Renewable Energy Sources ◽

Turbine Blades ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Wind Turbine Blades ◽

Element Analysis

Wind energy is one among the most promising renewable energy sources, and hence there is fast growth of wind energy farm implantation over the last decade, which is expected to be even faster in the coming years. Wind turbine blades are complex structures considering the different scientific fields involved in their study. Indeed, the study of blade performance involves fluid mechanics (aerodynamic study), solids mechanics (the nature of materials, the type of solicitations …), and the fluid coupling structure (IFS). The scope of the present work is to investigate the mechanical performances and structural integrity of a large offshore wind turbine blade under critical loads using blade element momentum. The resulting pressure was applied to the blade by the use of a user subroutine “DLOAD” implemented in ABAQUS finite element analysis software. The main objective is to identify and predict the zones which are sensitive to damage and failure as well as to evaluate the potential of composite materials (carbon fiber and glass fiber) and their effect on reduction of rotor’s weight, as well as the increase of resistance to wear, and stiffness.

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Damage Identification of Wind Turbine Blades Using Piezoelectric Transducers

Shock and Vibration ◽

10.1155/2014/430854 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Seong-Won Choi ◽

Kevin M. Farinholt ◽

Stuart G. Taylor ◽

Abraham Light-Marquez ◽

Gyuhae Park

Keyword(s):

Wind Turbine ◽

High Frequency ◽

Structural Integrity ◽

Damage Identification ◽

Turbine Blades ◽

Piezoelectric Transducers ◽

Detection Capability ◽

Wind Turbine Blades ◽

Sensors And Actuators ◽

Active Sensors

This paper presents the experimental results of active-sensing structural health monitoring (SHM) techniques, which utilize piezoelectric transducers as sensors and actuators, for determining the structural integrity of wind turbine blades. Specifically, Lamb wave propagations and frequency response functions at high frequency ranges are used to estimate the condition of wind turbine blades. For experiments, a 1 m section of a CX-100 blade is used. The goal of this study is to assess and compare the performance of each method in identifying incipient damage with a consideration given to field deployability. Overall, these methods yielded a sufficient damage detection capability to warrant further investigation. This paper also summarizes the SHM results of a full-scale fatigue test of a 9 m CX-100 blade using piezoelectric active sensors. This paper outlines considerations needed to design such SHM systems, experimental procedures and results, and additional issues that can be used as guidelines for future investigations.

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Delamination Detection in Composite T-Joints of Wind Turbine Blades using Microwaves

Advanced Composites Letters ◽

10.1177/096369351602500401 ◽

2016 ◽

Vol 25 (4) ◽

pp. 096369351602500 ◽

Cited By ~ 6

Author(s):

Zhen Li ◽

Arthur Haigh ◽

Constantinos Soutis ◽

Andrew Gibson ◽

Robin Sloan ◽

...

Keyword(s):

Wind Turbine ◽

Turbine Blade ◽

Structural Integrity ◽

Fibre Composite ◽

Turbine Blades ◽

Critical Issue ◽

Wind Turbine Blade ◽

Thickness Variation ◽

Wind Turbine Blades ◽

Delamination Detection

The wind turbine is playing an increasingly important role in the generation of green electricity. The structural integrity and maintenance of the wind turbine blade is a critical issue in service due to the harsh operating environments. In this paper, the delamination in glass fibre composite joints of a wind turbine blade is detected using the non-contact microwave imaging with an open-ended waveguide. The existence and extent of the delaminated region could be found from the generated images. Thickness variation and the presence of the web can be identified as well. The optimum inspection frequency range is investigated, which offers a reference for future applications. By comparison, the phase profiling provided by the scanning shows better performance for the delamination detection rather than the magnitude profiling.

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