Download or read book Application of Measured Loads to Wind Turbine Fatigue and Reliability Analysis written by Paul S. Veers and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of Measured Loads to Wind Turbine Fatigue and Reliability Analysis written by and published by . This book was released on 1997 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cyclic loadings produce progressive damage that can ultimately result in wind turbine structural failure. There are many issues that must be dealt with in turning load measurements into estimates of component fatigue life. This paper deals with how the measured loads can be analyzed and processed to meet the needs of both fatigue life calculations and reliability estimates. It is recommended that moments of the distribution of rainflow-range load amplitudes be calculated and used to characterize the fatigue loading. These moments reflect successively more detailed physical characteristics of the loading (mean, spread, tail behavior). Moments can be calculated from data samples and functional forms can be fitted to wind conditions, such as wind speed and turbulence intensity, with standard recession techniques. Distributions of load amplitudes that accurately reflect the damaging potential of the loadings can be estimated from the moments at any, wind condition of interest. Fatigue life can then be calculated from the estimated load distributions, and the overall, long-term, or design spectrum can be generated for any particular wind-speed distribution. Characterizing the uncertainty in the distribution of cyclic loads is facilitated by using a small set of descriptive statistics for which uncertainties can be estimated. The effects of loading parameter uncertainty can then be transferred to the fatigue life estimate and compared with other uncertainties, such as material durability.
Download or read book Methods of Structural Safety written by H. O. Madsen and published by Courier Corporation. This book was released on 2006-01-01 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: Uncertainties about analytical models, fluctuations in loads, and variability of material properties contribute to the small but real probability of structure failures. This advanced engineering text describes methods developed to deal with stochastic aspects of structural behavior, providing a framework for evaluating, comparing, and combining stochastic effects. Starting with the general problem of consistent evaluation of the reliability of structures, the text proceeds to examination of the second-moment reliability index methods that describe failure in terms of one or more limit states. It presents first-order reliability methods for computation of failure probabilities for individual limit states and for systems; and it illustrates identification of the design parameters most affecting reliability. Additional subjects include a self-contained presentation of extreme-value theory and stochastic processes; stationary, evolutionary, and nonlinear aspects of stochastic response of structures; a stochastic approach to material fatigue damage and crack propagation; and stochastic models for several natural and manufactured loads.
Download or read book CYCLES 2 0 written by Alok K. Jha and published by . This book was released on 1997 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: CYCLES is a computer program that computes the fatigue reliability of mechanical components. It includes a rather flexible model of uncertainty, both in distribution parameters of randomly varying quantities (e.g., load environment parameters such as wave height, wind speed, etc.) and in uncertain material properties (e.g., S-N fatigue properties). The formulation is intended to be of general applicability across a range of fatigue problems. Applications are shown here to offshore structures and wind turbines, both of which may experience fatigue problems. These models are efficiently analyzed through FORM/SORM techniques (first-and second-order reliability methods). A simple, analytical 9-function (limit state) is established, which may be directly incorporated into standard FORM/SORM software packages. We describe here one such code, which includes a 24-variable formulation, its capabilities, input parameters, and output. Fatigue reliability results are shown from this code for both wave and wind applications, including failure probability variation across a range of target fatigue lives.
Download or read book Wind Energy Systems written by John Dalsgaard Sørensen and published by Elsevier. This book was released on 2010-12-20 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: Large-scale wind power generation is one of the fastest developing sources of renewable energy and already makes a substantial contribution to power grids in many countries worldwide. With technology maturing, the challenge is now to increase penetration, and optimise the design, construction and performance of wind energy systems. Fundamental issues of safety and reliability are paramount in this drive to increase capacity and efficiency.Wind energy systems: Optimising design and construction for safe and reliable operation provides a comprehensive review of the latest developments in the design, construction and operation of large-scale wind energy systems, including in offshore and other problematic environments.Part one provides detailed coverage of wind resource assessment and siting methods relevant to wind turbine and wind farm planning, as well as aeroelastics, aerodynamics, and fatigue loading that affect the safety and reliability of wind energy systems. This coverage is extended in part two, where the design and development of individual components is considered in depth, from wind turbine rotors to drive train and control systems, and on to tower design and construction. Part three explores operation and maintenance issues, such as reliability and maintainability strategies and condition monitoring systems, before discussing performance assessment and optimisation routes for wind energy systems in low wind speed environments and cold climates. Part four reviews offshore wind energy systems development, from the impact of environmental loads such as wind, waves and ice, to site specific construction and integrated wind farm planning, and of course the critical issues and strategies for offshore operation and maintenance.With its distinguished editors and international teams of contributors, Wind energy systems is a standard reference for wind power engineers, technicians and manufacturers, as well as researchers and academics involved in this expanding field. - Reviews the latest developments in the design, construction and operation of large-scale wind energy systems - Offers detailed coverage of wind resource assessment and siting methods relevant to wind turbine and wind farm planning - Explores operation and maintenance issues, such as reliability and maintainability strategies and condition monitoring systems
Download or read book FAROW written by and published by . This book was released on 1993 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: FAROW is a computer program that evaluates the fatigue and reliability of wind turbine components using structural reliability methods. A deterministic fatigue life formulation is based on functional forms of three basic parts of wind turbine fatigue calculation: (1) the loading environment, (2) the gross level of structural response given the load environment, and (3) the local failure criterion given both load environment and gross stress response. The calculated lifetime is compared with a user specific target lifetime to assess probabilities of premature failure. The parameters of the functional forms can be defined as either constants or random variables. The reliability analysis uses the deterministic lifetime calculation as the limit state function of a FORM/SORM (first and second order reliability methods) calculation based on techniques developed by Rackwitz. Besides probability of premature failure, FAROW calculates the mean lifetime, the relative importance of each of the random variables, and the sensitivity of the results to all of the input parameters, both constant inputs and the parameters that define the random variable inputs. The ability to check the probability of failure with Monte Carlo simulation is included as an option.
Download or read book Advances in Wind Turbine Blade Design and Materials written by Povl Brondsted and published by Woodhead Publishing. This book was released on 2023-01-14 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Wind Turbine Blade Design and Materials, Second Edition, builds on the thorough review of the design and functionality of wind turbine rotor blades and the requirements and challenges for composite materials used in both current and future designs of wind turbine blades. - Reviews the design and functionality of wind turbine rotor blades - Examines the requirements and challenges for composite materials used in both current and future designs of wind turbine blades - Provides an invaluable reference for researchers and innovators in the field of wind
Download or read book A Collection of the 2004 ASME Wind Energy Symposium Technical Papers at the 42nd AIAA Aerospace Sciences Meeting and Exhibit written by and published by . This book was released on 2004 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stability Control and Reliable Performance of Wind Turbines written by Kenneth Eloghene Okedu and published by BoD – Books on Demand. This book was released on 2018-10-10 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended for academics and engineers working in universities, research institutes, and industry sectors wishing to acquire new information and enhance their knowledge of the current trends in wind turbine technology. Readers will gain new ideas and special experience with in-depth information about modeling, stability control, assessment, reliability, and future prospects of wind turbines. This book contains a number of problems and solutions that can be integrated into larger research findings and projects. The book enhances studies concerning the state of the art of wind turbines, modeling and intelligent control of wind turbines, power quality of wind turbines, robust controllers for wind turbines in cold weather, etc. The book also looks at recent developments in wind turbine supporting structures, noise reduction estimation methods, reliability and prospects of wind turbines, etc. As I enjoyed preparing this book, I am sure that it will be valuable for a large sector of readers.
Download or read book Linking Models and Experiments Volume 2 written by Tom Proulx and published by Springer Science & Business Media. This book was released on 2011-03-18 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Linking Models and Experiments, Volume 2. Proceedings of the 29th IMAC, A Conference and Exposition on Structural Dynamics, 2011, the second volume of six from the Conference, brings together 33 contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Structural Dynamics, including papers on Finite Element Techniques, Model Updating, Experimental Dynamics Substructuring, Model Validation, and Uncertainty Quantification.
Download or read book Reliability based Design Optimization of Composite Wind Turbine Blades for Fatigue Life Under Wind Load Uncertainty written by Weifei Hu and published by . This book was released on 2015 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this study are (1) to develop an accurate and efficient fatigue analysis procedure that can be used in reliability analysis and reliability-based design optimization (RBDO) of composite wind turbine blades; (2) to develop a wind load uncertainty model that provides realistic uncertain wind load for the reliability analysis and the RBDO process; and (3) to obtain an optimal composite wind turbine blade that satisfies target reliability for durability under the uncertain wind load. The current research effort involves: (1) developing an aerodynamic analysis method that can effectively calculate detailed wind pressure on the blade surface for stress analysis; (2) developing a fatigue failure criterion that can cope with non-proportional multi-axial stress states in composite wind turbine blades; (3) developing a wind load uncertainty model that represents realistic uncertain wind load for fatigue reliability of wind turbine systems; (4) applying the wind load uncertainty model into a composite wind turbine blade and obtaining an RBDO optimum design that satisfies a target probability of failure for a lifespan of 20 years under wind load uncertainty. In blade fatigue analysis, resultant aerodynamic forces are usually applied at the aerodynamic centers of the airfoils of a blade to calculate stress/strain. However, in reality the wind pressures are applied on the blade surface. A wind turbine blade is often treated as a typical beam-like structure for which fatigue life calculations are limited in the edge-wise and/or flap-wise direction(s). Using the beam-like structure, existing fatigue analysis methods for composite wind turbine blades cannot cope with the non-proportional multi-axial stress states that are endured by wind turbine blades during operation.
Download or read book Advanced Wind Turbine Technology written by Weifei Hu and published by Springer. This book was released on 2018-05-07 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the current challenges in modern wind turbine analysis, design and development, and provides a comprehensive examination of state-of-the-art technologies from both academia and industry. The twelve information-rich chapters cover a wide range of topics including reliability-based design, computational fluid dynamics, gearbox and bearing analyses, lightning analysis, structural dynamics, health condition monitoring, advanced techniques for field repair, offshore floating wind turbines, advanced turbine control and grid integration, and other emerging technologies. Each chapter begins with the current status of technology in a lucid, is easy-to-follow treatment, then elaborates on the corresponding advanced technology using detailed methodologies, graphs, mathematical models, computational simulations, and experimental instrumentation. Relevant to a broad audience from students and faculty to researchers, manufacturers, and wind energy engineers and designers, the book is ideal for both educational and research needs. Presents the latest developments in reliability-based design optimization, CFD of wind turbines, structural dynamics for wind turbine blades, off-shore floating wind turbines, advanced wind turbine control, and wind power and ramp forecasting for grid integration; Includes techniques for wind turbine gearboxes and bearings, evaluation of lightning strike damage, health condition monitoring and reparation techniques; Illustrates theories and operational considerations using graphics, tables, computational algorithms, simulation models, and experimental instrumentation; Examines unique, innovative technologies for wind energy.
Download or read book Wind Energy for the Next Millennium written by E. L. Petersen and published by Earthscan. This book was released on 1999 with total page 1290 pages. Available in PDF, EPUB and Kindle. Book excerpt: First Published in 1999. Routledge is an imprint of Taylor & Francis, an informa company.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Case Study and Reliability Analyses for Wind Turbines written by and published by . This book was released on 1994 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern wind turbines are fatigue critical machines used to produce electrical power. To insure long term, reliable operation, their structure must be optimized if they are to be economically viable. The fatigue and reliability projects in Sandia's Wind Energy Program are developing the analysis tools required to accomplish these design requirements. The first section of the paper formulates the fatigue analysis of a wind turbine using a cumulative damage technique. The second section uses reliability analysis for quantifying the uncertainties and the inherent randomness associated with turbine performance and the prediction of service lifetimes. Both research areas are highlighted with typical results.
Download or read book A Collection of the 1999 ASME Wind Energy Symposium Technical Papers written by American Institute of Aeronautics and Astronautics and published by . This book was released on 1999 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume collects together the 1999 ASME Wind Energy Symposium technical papers.
Download or read book Biaxial Dynamic Fatigue Tests of Wind Turbine Blades written by Falko Bürkner and published by Fraunhofer Verlag. This book was released on 2021-04-09 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Testing rotor blades of wind turbines is essential to mitigate financial risks caused by serial damages. Present day uniaxial dynamic tests are time consuming and often inaccurate regarding the applied loading. This thesis proposes a faster fatigue test method by loading the two primary directions at the same time. In addition, a more realistic test, compared to uniaxial tests, is accomplished by loading larger areas of the blade cross-sections. To achieve this, an elliptical biaxial dynamic excitation is used. To fulfill the industry requirement for cost effective tests, a relatively simple test setup was developed, still achieving an elliptical dynamic excitation of the rotor blade. Two methods for an accurate determination of the applied loadings for dynamic fatigue tests are described. These calibration tests use easily measured values and simple analysis to achieve accurate test load measurements in a cost-effective way.
