Applications of Passive Vibration Control and Damage Detection in Composite Wind Turbine Blades
Title | Applications of Passive Vibration Control and Damage Detection in Composite Wind Turbine Blades PDF eBook |
Author | Jeffery Dwayne Tippmann |
Publisher | |
Pages | 106 |
Release | 2014 |
Genre | |
ISBN | 9781321452037 |
The aim of this dissertation was to develop passive techniques for vibration control and structural health monitoring applications in structures operating in conditions of significant ambient noise. These goals were accomplished through the use of an experimental wind turbine blade that represents the materials and design of a full scale wind turbine with the inclusion of devices simulating the presence of known manufacturing defects. The vibration control aim was accomplished using a shunted array of piezoelectric elements tuned to the vibration properties of the blade skin. The macro-fiber composite (MFC) composite piezoelectric transducer was bonded to the wind turbine blade skin and connected to the tuned shunt circuit. The damage detection techniques were developed using both an aluminum plate and the experimental wind turbine blade. Two approaches using a reconstructed impulse response function are presented. The first examines the break in reciprocity of impulse response functions. A single similarity damage index was proposed and then extended into a multi-feature analysis. The second method applied linear and nonlinear beamforming techniques using an experimentally generated replica field and cross-spectral signal processing techniques. The passive reconstruction of the impulse response function between two sensors is an important topic in NDE and SHM. Previously studied methods using active pitch-catch approaches between any two sensors is well suited for structures such as wind turbine blades that experience significant amounts of noise during operation. The study of these approaches advances the understanding of passive damage detection using reconstructed impulse response functions.
Acoustic Emission Signal Analysis and Damage Mode Identification of Composite Wind Turbine Blades
Title | Acoustic Emission Signal Analysis and Damage Mode Identification of Composite Wind Turbine Blades PDF eBook |
Author | Pengfei Liu |
Publisher | Elsevier |
Pages | 366 |
Release | 2023-05-20 |
Genre | Technology & Engineering |
ISBN | 0323886477 |
Acoustic Emission Signal Analysis and Damage Mode Identification of Composite Wind Turbine Blades covers both the underlying theory and various techniques for effective structural monitoring of composite wind turbine blades via acoustic emission signal analysis, helping readers solve critical problems such as noise elimination, defect detection, damage mode identification, and more. Author Pengfei Liu introduces techniques for identifying and analyzing progressive failure under tension, delamination, damage localization, adhesive composite joint failure, and other degradation phenomena, outlining methods such as time-difference, wavelet, machine learning, and more including combined methods. The disadvantages and advantages of using each method are covered as are techniques for different blade-lengths and various blade substructures. Piezoelectric sensors are discussed as is experimental analysis of damage source localization. The book also takes great lengths to let readers know when techniques and concepts discussed can be applied to composite materials and structures beyond just wind turbine blades. - Features fundamental acoustic emission theories and techniques for monitoring the structural integrity of wind turbine blades - Covers sensor arrangements, noise elimination, defect detection, and dominating damage mode identification using acoustic emission techniques - Outlines the wavelet method, the time-difference defect detection method, and damage mode identification techniques using machine learning - Discusses how the techniques covered can be extended and adapted for use in other composite structures under complex loads and in different environments
Experimental Investigation in Vibration Control and Damage Detection of Smart Composites
Title | Experimental Investigation in Vibration Control and Damage Detection of Smart Composites PDF eBook |
Author | |
Publisher | |
Pages | 0 |
Release | 2001 |
Genre | |
ISBN |
The Laser Doppler Vibrometer (LDV) optical instrument purchased under the DURIP grant is used for accurately measuring velocity (and displacement) of vibrating surfaces completely without contact. It is a complete, self-contained area vibration measurement and analysis system. The LDV automatically collects complete vibration data from up to thousands of individual points on a user-defined area. An important feature in scanning vibrometers is the ability to validate and improve the quality of measured data at every scan point. This overcomes problems caused by dark speckles and other unavoidable phenomena present in laser vibrometry. The system purchased is also equipped with Live and Fully Integrated Video Imaging. The equipment is particularly useful at higher frequencies (above Skit) where accelerometers become increasingly inaccurate due to their own dynamic characteristics and influences. A large number of applications that require measurements at very high frequencies and cannot be accomplished using accelerometers include piezoelectric transducers and exciters, NDE flaw detection, rotor blades, disk drive components and micro-sensors and actuators.
Mechanics of Composite and Multi-functional Materials, Volume 7
Title | Mechanics of Composite and Multi-functional Materials, Volume 7 PDF eBook |
Author | Carter Ralph |
Publisher | Springer |
Pages | 457 |
Release | 2015-10-30 |
Genre | Technology & Engineering |
ISBN | 3319217623 |
Experimental Mechanics of Composite, Hybrid, and Multifunctional Materials, Volume 7 of the Proceedings of the 2015SEM Annual Conference& Exposition on Experimental and Applied Mechanics, the seventh volume of nine from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on a wide range of areas, including: Multifunctional Materials Hybrid Materials Novel Composites Nano- and Particle-Reinforced Composites Additive Manufacturing of Composites Digital Imaging of Composites Damage Detection Non-Destructive Evaluation Fatigue and Fracture of Composites Manufacturing and Joining of Composites Advanced Composites Applications
Structural Analysis of Composite Wind Turbine Blades
Title | Structural Analysis of Composite Wind Turbine Blades PDF eBook |
Author | Dimitris I Chortis |
Publisher | Springer Science & Business Media |
Pages | 240 |
Release | 2013-06-29 |
Genre | Technology & Engineering |
ISBN | 3319008641 |
This book concerns the development of novel finite elements for the structural analysis of composite beams and blades. The introduction of material damping is also an important aspect of composite structures and it is presented here in terms of their static and dynamic behavior. The book thoroughly presents a new shear beam finite element, which entails new blade section mechanics, capable of predicting structural blade coupling due to composite coupling and/or internal section geometry. Theoretical background is further expanded towards the inclusion of nonlinear structural blade models and damping mechanics for composite structures. The models effectively include geometrically nonlinear terms due to large displacements and rotations, improve the modeling accuracy of very large flexible blades, and enable the modeling of rotational stiffening and buckling, as well as, nonlinear structural coupling. Validation simulations on specimen level study the geometric nonlinearities effect on the modal frequencies and damping values of composite strips of various angle-ply laminations under either tensile or buckling loading. A series of correlation cases between numerical predictions and experimental measurements give credence to the developed nonlinear beam finite element models and underline the essential role of new nonlinear damping and stiffness terms.
Scientific and Technical Aerospace Reports
Title | Scientific and Technical Aerospace Reports PDF eBook |
Author | |
Publisher | |
Pages | 548 |
Release | 1995 |
Genre | Aeronautics |
ISBN |
Vibration-Based Condition Monitoring of Wind Turbines
Title | Vibration-Based Condition Monitoring of Wind Turbines PDF eBook |
Author | Tomasz Barszcz |
Publisher | Springer |
Pages | 233 |
Release | 2018-12-04 |
Genre | Technology & Engineering |
ISBN | 3030059715 |
This book describes in detail different types of vibration signals and the signal processing methods, including signal resampling and signal envelope, used for condition monitoring of drivetrains. A special emphasis is placed on wind turbines and on the fact that they work in highly varying operational conditions. The core of the book is devoted to cutting-edge methods used to validate and process vibration data in these conditions. Key case studies, where advanced signal processing methods are used to detect failures of gearboxes and bearings of wind turbines, are described and discussed in detail. Vibration sensors, SCADA (Supervisory Control and Data Acquisition), portable data analyzers and online condition monitoring systems, are also covered. This book offers a timely guide to both researchers and professionals working with wind turbines (but also other machines), and to graduate students willing to extend their knowledge in the field of vibration analysis.