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Framework of Designing an Adaptive and Multi-Regime Prognostics and Health Management for Wind Turbine Reliability and Efficiency Improvement
B.L. Song,J.Lee
International Journal of Advanced Computer Sciences and Applications , 2013,
Abstract: Wind turbine systems are increasing in technical complexity, and tasked with operating and degrading in highly dynamic and unpredictable conditions. Sustaining the reliability of such systems is a complex and difficult task. In spite of extensive efforts, current prognostics and health management (PHM) methodologies face many challenges, due to the complexity of the degradation process and the dynamic operating conditions of a wind turbine. This research proposed a novel adaptive and multi-regime prognostics and health management (PHM) approach with the aim to tackle the challenges of traditional methods. With this approach, a scientific and systematic solution is provided for health assessment, diagnosis and prognosis of critical components of wind turbines under varying environmental, operational and aging processes. The system is also capable of adaptively selecting the tools suitable for a component under a certain health status and a specific operating condition. The adopted relevant health assessment, diagnosis and prognosis tools and techniques for wind turbines are warranted by the intensive research of PHM models by the IMS center for common rotary machinery components. Some sub-procedures, such as information reconstruction, regime clustering approach and the prognostics of rotating elements, were validated by the best score performance in PHM Data Challenge 2008 (student group) and 2009 (professional group). The success of the proposed wind turbine PHM system would greatly benefit current wind turbine industry.
The Design of Vertical Axis Wind Turbine Rotor for Antarctic  [PDF]
Zhai Yuyi,Zeng Decai,Liu Liang,Tang Wenbin
Information Technology Journal , 2013,
Abstract: While wind power (WP) is a popular research issue in vigorously promoting green energy era, the research of the utilization of wind energy based on Antarctic moving platforms is still rarely involved. In this study, a kind of rotor for Vertical Axis Wind Turbine (VAWTs) was introduced which is first equipped on a moving platform for Antarctic’s exploring. The fluid simulation software Fluent was used to analyze and compare the performance of four different airfoil shape of wind turbine. To reduce the number of times of simulation and trial effectively, the uniform optimal design method was adopt to optimize the parameters of the radius of rotor, blades number, blade chord length and blade installation angle and the values of various parameters of the wind rotor and the efficiency of wind power affected by the complex influence of the four factors were obtained. Finally, the wind hub structure and materials were analyzed with ANSYS software and by the static and modal analysis, the reliability of the wind turbine in strong wind was verified which laid the foundation for the producing of wind turbine with higher efficiency in the future.
Mapping Ontario’s Wind Turbines: Challenges and Limitations  [PDF]
Tanya Christidis,Jane Law
ISPRS International Journal of Geo-Information , 2013, DOI: 10.3390/ijgi2041092
Abstract: Despite rapid and vast development of wind turbines across the Canadian province of Ontario, there is no map available indicating the location of each wind turbine. A map of this nature is crucial for health and environmental risk research and has many applications in other fields. Research examining health and wind turbines is limited by the available maps showing the nearest community to a wind farm as opposed to each unique wind turbine. Data from provincial-level organizations, developers, and municipalities were collected using government development approval documents, planning documents, and data given directly from municipalities and developers. Wind turbines were mapped using Google Earth, coordinate lists, shapefiles, and translating data from other maps. In total, 1,420 wind turbines were mapped from 56 wind farms. The limitations of each data source and mapping method are discussed. There are numerous challenges in creating a map of this nature, for example incorrect inclusion of wind farms and inaccuracies in wind turbine locations. The resultant map is the first of its kind to be discussed in the literature, can be used for a variety of health and environmental risk studies to assess dose-response, wind turbine density, visibility, and to create sound and vibration models.
Human Health, Rights and Wind Turbine Deployment in Canada  [PDF]
Carmen Krogh, Brett Horner
Open Journal of Social Sciences (JSS) , 2017, DOI: 10.4236/jss.2017.55012
Abstract: Canada has ratified international conventions which recognize the individual’s right to the enjoyment of the highest attainable standard of health. Despite the adoption of these covenants governments sometimes support policies and practises which trade off individual human health with other conflicting interests. This review evaluates the individual’s right to health against government policies and practices which support wind energy deployment in Canada. Our analysis presents government documents, peer reviewed literature, and other references which support the conclusion that wind energy deployment in Canada can be expected to result in avoidable harm to human health. This harm conflicts with contemporary health and social justice principles. Governments have a responsibility to help Canadians maintain and improve their health by generating effective responses for the prevention of avoidable harm. Individuals have a right to make informed decisions about their health. Knowledge gaps and potential risks to health should be fully disclosed. Individuals should not be exposed to industrial wind turbines without their informed consent.
Proto-Magnetars as GRB Central Engines: Uncertainties, Limitations, and Particulars  [PDF]
Todd A. Thompson,Brian D. Metzger,Niccolò Bucciantini
Physics , 2010, DOI: 10.1063/1.3509357
Abstract: The millisecond proto-magnetar model for the central engine of long-duration gamma-ray bursts is briefly reviewed. Limitations and uncertainties in the model are highlighted. A short discussion of the maximum energy, maximum duration, radiative efficiency, jet formation mechanism, late-time energy injection, and (non-)association with supernovae of millisecond magnetar-powered GRBs is provided.
Damage Identification of Wind Turbine Blades Using Piezoelectric Transducers  [PDF]
Seong-Won Choi,Kevin M. Farinholt,Stuart G. Taylor,Abraham Light-Marquez,Gyuhae Park
Shock and Vibration , 2014, DOI: 10.1155/2014/430854
Abstract: 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. 1. Introduction Wind turbines are becoming a larger source of renewable energy in the world. The US government projects that 20% of the US electrical supply could be produced via wind power by 2030 [1]. To achieve this goal, the turbine manufacturers have been increasing the size of the turbine blades, often made of composite materials, to maximize power output. As a result of severe wind loadings and the material level flaws in composite structures, blade failure has been a more common occurrence in the wind industry. Monitoring the structural health of the turbine blades is particularly important as they account for 15–20% of the total turbine cost. In addition, blade damage is the most expensive type of damage to repair and can cause serious secondary damage to the wind turbine system due to rotating imbalance created during blade failure. Therefore, it is imperative that a structural health monitoring (SHM) system be incorporated into the design of the wind turbines in order to monitor flaws before they lead to a catastrophic failure. There has been a considerable research effort focused on applying SHM techniques on wind turbine blades [2, 3]. However, most of these studies focus on a single technique for damage detection; consequently very little work has been done to compare the results of multiple active-sensing techniques. Thus, the goal of this study is to assess the relative performance of high-frequency SHM techniques, namely, Lamb wave propagation and frequency response functions (FRFs), as a way to nondestructively
Latest Findings on the Health Risks of  [PDF]
Vera Markovi?,Dejan Krsti?,Olivera Proni?-Ran?i?,Zlatica Marinkovi?
Microwave Review , 2012,
Abstract: An overview of the latest research pertaining to biological effects of mobile phone radiation is presented in this paper. Having in mind the enormous popularity of mobile phone use worldwide, a serious concern about the health risks has appeared. Some research results in this area as well as recently published alert of the World Health Organization (WHO) on the biological effects of electromagnetic radiation are presented.
Gas Turbine Health State Determination: Methodology Approach and Field Application  [PDF]
Michele Pinelli,Pier Ruggero Spina,Mauro Venturini
International Journal of Rotating Machinery , 2012, DOI: 10.1155/2012/142173
Abstract: A reduction of gas turbine maintenance costs, together with the increase in machine availability and the reduction of management costs, is usually expected when gas turbine preventive maintenance is performed in parallel to on-condition maintenance. However, on-condition maintenance requires up-to-date knowledge of the machine health state. The gas turbine health state can be determined by means of Gas Path Analysis (GPA) techniques, which allow the calculation of machine health state indices, starting from measurements taken on the machine. Since the GPA technique makes use of field measurements, the reliability of the diagnostic process also depends on measurement reliability. In this paper, a comprehensive approach for both the measurement validation and health state determination of gas turbines is discussed, and its application to a 5?MW gas turbine working in a natural gas compression plant is presented. 1. Introduction Maintaining high levels of availability and reliability is an essential objective for all production units, especially for those that are subject to high costs due to loss of production. Nonscheduled stops due to unforeseen faults cause relevant costs related to the reduction or the interruption of the process and to the consequent repairing actions. For this reason, in strategic applications, stand-by machines are usually required to ensure the desired level of availability. In the last decades, gas turbines have been more and more used either for power generation or as mechanical drive (e.g., in natural gas compression plants), thanks to their favorable characteristics with respect to other technologies, such as low emissions and high availability and reliability. In particular, the latter issues represent winning features of gas-turbine-based power plants. Hence, in order to utilize these systems as effectively as possible, the management of machine maintenance must be optimized. The optimization of maintenance management, which should lead to cost saving and increase in machine availability, can be performed by supporting gas turbine preventive maintenance (which comes from manufacturer experience in terms of component life and performance degradation versus working hours and is performed according to a priori schedules, regardless of the effective gas turbine health state) with on-condition maintenance, which consists of ?“ad hoc” actions descending from gas turbine actual operating state [1–7]. Therefore, On-condition maintenance requires up-to-date knowledge of the machine health state in real time. One of the most
Analysis of clinical uncertainties by health professionals and patients: an example from mental health
Keith Lloyd, Matteo Cella, Michael Tanenblatt, Anni Coden
BMC Medical Informatics and Decision Making , 2009, DOI: 10.1186/1472-6947-9-34
Abstract: From a survey of uncertainties about the treatment of schizophrenia we describe, categorise and analyse the type of questions asked by mental health professionals and patients about treatment uncertainties for schizophrenia. We explore the value of mapping from an unstructured to a structured framework, test inter-rater reliability for this task, develop a linguistic taxonomy, and cross tabulate that taxonomy with elements of a well structured clinical question.Few of the 78 Patients and 161 clinicians spontaneously asked well structured queries about treatment uncertainties for schizophrenia. Uncertainties were most commonly about drug treatments (45.3% of clinicians and 41% of patients), psychological therapies (19.9% of clinicians and 9% of patients) or were unclassifiable.(11.8% of clinicians and 16.7% of patients). Few naturally asked questions could be classified using the well structured and focused clinical question format (i.e. PICO format). A simple linguistic taxonomy better described the types of questions people naturally ask.People do not spontaneously ask well structured clinical questions. Other taxonomies may better capture the nature of questions. However, access to EBM resources is greatly facilitated by framing enquiries in the language of EBM, such as posing queries in PICO format. People do not naturally do this. It may be preferable to identify a way of searching the literature that more closely matches the way people naturally ask questions if access to information about treatments are to be made more broadly available.When practising evidence-based medicine (EBM), the ability to translate clinical queries into structured and focused clinical questions has been described as the first step of evidence based practice[1,2]. In this way, it is argued, that answers can be found where evidence exists from systematic reviews and clinical trials. If the clinical question cannot be answered by referring to the evidence base then an uncertainty has bee
Wind Turbine Blade Design  [PDF]
Peter J. Schubel,Richard J. Crossley
Energies , 2012, DOI: 10.3390/en5093425
Abstract: A detailed review of the current state-of-art for wind turbine blade design is presented, including theoretical maximum efficiency, propulsion, practical efficiency, HAWT blade design, and blade loads. The review provides a complete picture of wind turbine blade design and shows the dominance of modern turbines almost exclusive use of horizontal axis rotors. The aerodynamic design principles for a modern wind turbine blade are detailed, including blade plan shape/quantity, aerofoil selection and optimal attack angles. A detailed review of design loads on wind turbine blades is offered, describing aerodynamic, gravitational, centrifugal, gyroscopic and operational conditions.
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