The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Andreas Nuber - One of the best experts on this subject based on the ideXlab platform.
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radar based structural health monitoring of wind Turbine Blades the case of damage detection
Structural Health Monitoring-an International Journal, 2018Co-Authors: Jochen Moll, Philip Arnold, Moritz Malzer, Viktor Krozer, Dimitry Pozdniakov, Rahmi Salman, Stephan Rediske, Markus Scholz, Herbert Friedmann, Andreas NuberAbstract:Structural health monitoring of wind Turbine Blades is challenging due to its large dimensions, as well as the complex and heterogeneous material system. In this article, we will introduce a radically new structural health monitoring approach that uses permanently installed radar sensors in the microwave and millimetre-wave frequency range for remote and in-service inspection of wind Turbine Blades. The radar sensor is placed at the tower of the wind Turbine and irradiates the electromagnetic waves in the direction of the rotating Blades. Experimental results for damage detection of complex structures will be presented in a laboratory environment for the case of a 10-mm-thick glass-fibre-reinforced plastic plate, as well as a real blade-tip sample.
Jochen Moll - One of the best experts on this subject based on the ideXlab platform.
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radar based structural health monitoring of wind Turbine Blades the case of damage detection
Structural Health Monitoring-an International Journal, 2018Co-Authors: Jochen Moll, Philip Arnold, Moritz Malzer, Viktor Krozer, Dimitry Pozdniakov, Rahmi Salman, Stephan Rediske, Markus Scholz, Herbert Friedmann, Andreas NuberAbstract:Structural health monitoring of wind Turbine Blades is challenging due to its large dimensions, as well as the complex and heterogeneous material system. In this article, we will introduce a radically new structural health monitoring approach that uses permanently installed radar sensors in the microwave and millimetre-wave frequency range for remote and in-service inspection of wind Turbine Blades. The radar sensor is placed at the tower of the wind Turbine and irradiates the electromagnetic waves in the direction of the rotating Blades. Experimental results for damage detection of complex structures will be presented in a laboratory environment for the case of a 10-mm-thick glass-fibre-reinforced plastic plate, as well as a real blade-tip sample.
Bent F. Sørensen - One of the best experts on this subject based on the ideXlab platform.
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Materials for wind Turbine Blades: An overview
Materials, 2017Co-Authors: Leon Mishnaevsky, Justine Beauson, Malcolm Mcgugan, Kim Branner, Helga Norgaard Petersen, Bent F. SørensenAbstract:A short overview of composite materials for wind Turbine applications is presented here. Requirements toward the wind Turbine materials, loads, as well as available materials are reviewed. Apart from the traditional composites for wind Turbine Blades (glass fibers/epoxy matrix composites), natural composites, hybrid and nanoengineered composites are discussed. Manufacturing technologies for wind Turbine composites, as well their testing and modelling approaches are reviewed.
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Reliability of Wind Turbine Blades: An Overview of Materials Testing
2007Co-Authors: John W. Holmes, Bent F. Sørensen, Povl BrøndstedAbstract:The structural reliability of wind Turbine components can have a profound impact on both the profitability and reputation of a wind Turbine manufacturer or supplier of wind Turbine components. The issue of reliability is of critical concern when large wind farm co-operatives are considered, and when wind Turbines are located in remote regions where the cost of inspections and repairs can be very high. From a structural viewpoint, wind Turbine Blades are subjected to very complex loading histories with coupled deformation modes. The long-term reliability of wind Turbine Blades requires an understanding of how damage develops in composite structures, composite materials and adhesives. Designing reliable wind Turbine Blades also requires the further development of laboratory scale and full scale test methods to evaluate the structural response and durability of new materials under various loading and environmental conditions. This paper highlights recent advances in methods used to characterize adhesive joints in wind Turbine Blades and the manner in which laboratory data is used to predict the structural response of wind Turbine Blades.
Youming Chen - One of the best experts on this subject based on the ideXlab platform.
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a review of full scale structural testing of wind Turbine Blades
Renewable & Sustainable Energy Reviews, 2014Co-Authors: Hf F Zhou, Hy Y Dou, Lz Z Qin, Youming ChenAbstract:Abstract The Blades that play a key role to collect wind energy are the most critical components of a wind Turbine system. Meanwhile, they are also the parts most susceptible to damage. Structural health monitoring (SHM) system has been proposed to continuously monitor the wind Turbine. Nevertheless, no system has yet been developed to a stage compatible with the requirements of commercial wind Turbines. Therefore, full-scale structural testing is the main means available so far for validating the comprehensive performance of wind Turbine Blades. It is now normally used as part of a blade certification process. It also allows an insight into the failure mechanisms of wind Turbine Blades, which are essential to the success of SHM. Furthermore, it provides a unique opportunity to exercise SHM and non-destructive testing (NDT) techniques. Recognizing these practical significances, this paper therefore aims to carry out an extensive review of full-scale structural testing of wind Turbine Blades, including static testing and fatigue testing. In particular, the current status in China is presented. One focus of this review is on the failure mechanisms of wind Turbine Blades, which are vital for optimizing the design of themselves as well as the design of their SHM system. Another focus is on the strengths and weaknesses of various SHM and NDT techniques, which are useful for evaluating their applicability on wind Turbine Blades. In addition, recent advances in photogrammetry and digital image correlation have allowed new opportunities for blade monitoring. These techniques are currently being explored on a few wind Turbine blade applications and can provide a wealth of additional information that was previously unobtainable. These works are also summarized in this paper in order to discover the pros and cons of these techniques.
John Dalsgaard Sørensen - One of the best experts on this subject based on the ideXlab platform.
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Reliability-Based Design of Wind Turbine Blades
Structural Safety, 2011Co-Authors: Henrik Stensgaard Toft, John Dalsgaard SørensenAbstract:Abstract Reliability-based design of wind Turbine Blades requires identification of the important failure modes/limit states along with stochastic models for the uncertainties and methods for estimating the reliability. In the present paper it is described how reliability-based design can be applied to wind Turbine Blades. For wind Turbine Blades, tests with the basic composite materials and a few full-scale Blades are normally performed during the design process. By adopting a reliability-based design approach, information from these tests can be taken into account in a rational way during the design process. In the present paper, a probabilistic framework for design of wind Turbine Blades are presented and it is demonstrated how information from tests can be taken into account using the Maximum-Likelihood method and Bayesian statistics. In a numerical example, the reliability is estimated for a wind Turbine blade in both ultimate and fatigue limit states. Information from tests is used to formulate the stochastic models used in the limit state equations. Partial safety factors for use in traditional deterministic design are estimated using the stochastic models.
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defect distribution and reliability assessment of wind Turbine Blades
Engineering Structures, 2011Co-Authors: Henrik Stensgaard Toft, Kim Branner, John Dalsgaard Sørensen, Peter BerringAbstract:Abstract In this paper, two stochastic models for the distribution of defects in wind Turbine Blades are proposed. The first model assumes that the individual defects are completely randomly distributed in the blade. The second model assumes that the defects occur in clusters of different size, based on the assumption that one error in the production process tends to trigger several defects. For both models, additional information, such as number, type, and size of the defects, is included as stochastic variables. In a numerical example, the reliability is estimated for a generic wind Turbine blade model both with and without defects in terms of delaminations. The reliability of the blade decreases when defects are included. However, the distribution of the defects influences how much the reliability is decreased. It is also shown how non-destructive inspection (NDI) after production can be used to update the reliability for the wind Turbine blade using Bayesian statistics.
