WorldWideScience

Sample records for wind atlas analysis

  1. The Irish Wind Atlas

    Energy Technology Data Exchange (ETDEWEB)

    Watson, R. [Univ. College Dublin, Dept. of Electronic and Electrical Engineering, Dublin (Ireland); Landberg, L. [Risoe National Lab., Meteorology and Wind Energy Dept., Roskilde (Denmark)

    1999-03-01

    The development work on the Irish Wind Atlas is nearing completion. The Irish Wind Atlas is an updated improved version of the Irish section of the European Wind Atlas. A map of the irish wind resource based on a WA{sup s}P analysis of the measured data and station description of 27 measuring stations is presented. The results of previously presented WA{sup s}P/KAMM runs show good agreement with these results. (au)

  2. An Icelandic wind atlas

    Science.gov (United States)

    Nawri, Nikolai; Nína Petersen, Gudrun; Bjornsson, Halldór; Arason, Þórður; Jónasson, Kristján

    2013-04-01

    While Iceland has ample wind, its use for energy production has been limited. Electricity in Iceland is generated from renewable hydro- and geothermal source and adding wind energy has not be considered practical or even necessary. However, adding wind into the energy mix is becoming a more viable options as opportunities for new hydro or geothermal power installation become limited. In order to obtain an estimate of the wind energy potential of Iceland a wind atlas has been developed as a part of the Nordic project "Improved Forecast of Wind, Waves and Icing" (IceWind). The atlas is based on mesoscale model runs produced with the Weather Research and Forecasting (WRF) Model and high-resolution regional analyses obtained through the Wind Atlas Analysis and Application Program (WAsP). The wind atlas shows that the wind energy potential is considerable. The regions with the strongest average wind are nevertheless impractical for wind farms, due to distance from road infrastructure and power grid as well as harsh winter climate. However, even in easily accessible regions wind energy potential in Iceland, as measured by annual average power density, is among the highest in Western Europe. There is a strong seasonal cycle, with wintertime power densities throughout the island being at least a factor of two higher than during summer. Calculations show that a modest wind farm of ten medium size turbines would produce more energy throughout the year than a small hydro power plants making wind energy a viable additional option.

  3. Wind Atlas for Egypt

    DEFF Research Database (Denmark)

    The results of a comprehensive, 8-year wind resource assessment programme in Egypt are presented. The objective has been to provide reliable and accurate wind atlas data sets for evaluating the potential wind power output from large electricityproducing wind turbine installations. The regional wind...... climates of Egypt have been determined by two independent methods: a traditional wind atlas based on observations from more than 30 stations all over Egypt, and a numerical wind atlas based on long-term reanalysis data and a mesoscale model (KAMM). The mean absolute error comparing the two methods is about...... 10% for two large-scale KAMM domains covering all of Egypt, and typically about 5% for several smaller-scale regional domains. The numerical wind atlas covers all of Egypt, whereas the meteorological stations are concentrated in six regions. The Wind Atlas for Egypt represents a significant step...

  4. Wind Atlas for Egypt

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Said Said, Usama; Badger, Jake

    2006-01-01

    The results of a comprehensive, 8-year wind resource assessment programme in Egypt are presented. The objective has been to provide reliable and accurate wind atlas data sets for evaluating the potential wind power output from large electricityproducing wind turbine installations. The regional wind...... climates of Egypt have been determined by two independent methods: a traditional wind atlas based on observations from more than 30 stations all over Egypt, and a numerical wind atlas based on long-term reanalysis data and a mesoscale model (KAMM). The mean absolute error comparing the two methods is about...... 10% for two large-scale KAMM domains covering all of Egypt, and typically about 5% for several smaller-scale regional domains. The numerical wind atlas covers all of Egypt, whereas the meteorological stations are concentrated in six regions. The Wind Atlas for Egypt represents a significant step...

  5. Wind Atlas Analysis and Application Program: WAsP 11 Help Facility

    DEFF Research Database (Denmark)

    2014-01-01

    The Wind Atlas Analysis and Application Program (WAsP) is a PC-program for horizontal and vertical extrapolation of wind climates. The program contains a complete set of models to calculate the effects on the wind of sheltering obstacles, surface roughness changes and terrain height variations...... of specific wind turbines and wind farms. The WAsP Help Facility includes a Quick Start Tutorial, a User's Guide and a Technical Reference. It further includes descriptions of the Observed Wind Climate Wizard, the WAsP Climate Analyst, the WAsP Map Editor tool, the WAsP Turbine Editor tool, the Air Density...

  6. South Baltic Wind Atlas

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo; Hahmann, Andrea N.; Hasager, Charlotte Bay

    A first version of a wind atlas for the South Baltic Sea has been developed using the WRF mesoscale model and verified by data from tall Danish and German masts. Six different boundary-layer parametrization schemes were evaluated by comparing the WRF results to the observed wind profiles at the m......A first version of a wind atlas for the South Baltic Sea has been developed using the WRF mesoscale model and verified by data from tall Danish and German masts. Six different boundary-layer parametrization schemes were evaluated by comparing the WRF results to the observed wind profiles...

  7. Nova Scotia wind atlas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    In order to stimulate growth of the wind energy sector in the province of Nova Scotia and to optimize the development of an important renewable energy source in the province, the Nova Scotia Department of Energy has launched the Nova Scotia wind atlas project. The atlas provides valuable information regarding the identification of the optimal locations to install wind farm turbines, both at the large utility scale level and at the private or small business levels. This article presented information on the wind atlas website and on wind resource maps. Background information on the project was presented. The wind resource maps were developed in partnership by the K.C, Irving Chair in Sustainable Development at Moncton University and the Applied Geomatics Research Group at the Nova Scotia Community College. The wind resource maps are available for viewing on the website where users can click on tile section to obtain enlarged versions of wind resource maps for different parts of the province of Nova Scotia. The maps were developed using computer modelling. 7 figs.

  8. Production of the Finnish Wind Atlas

    DEFF Research Database (Denmark)

    Tammelin, Bengt; Vihma, Timo; Atlaskin, Evgeny

    2013-01-01

    The Finnish Wind Atlas was prepared applying the mesoscale model AROME with 2.5 km horizontal resolution and the diagnostic downscaling method Wind Atlas Analysis and Application Programme (WAsP) with 250 m resolution. The latter was applied for areas most favourable for wind power production: a 30......) the parameterization method for gust factor was extended to be applicable at higher altitudes; and (vii) the dissemination of the Wind Atlas was based on new technical solutions. The AROME results were calculated for the heights of 50, 75, 100, 125, 150, 200, 300 and 400 m, and the WAsP results for the heights of 50......, 75, 100, 125 and 150 m. In addition to the wind speed, the results included the values of the Weibull distribution parameters, the gust factor, wind power content and the potential power production, which was calculated for three turbine sizes. The Wind Atlas data are available for each grid point...

  9. Wind Atlas of Bay of Bengal with Satellite Wind Measurement

    DEFF Research Database (Denmark)

    Nadi, Navila Rahman

    The objective of this study is to obtain appropriate offshore location in the Bay of Bengal, Bangladesh for further development of wind energy. Through analyzing the previous published works, no offshore wind energy estimation has been found here. That is why, this study can be claimed as the first...... footstep towards offshore wind energy analysis for this region. Generally, it is difficult to find offshore wind data relative to the wind turbine hub heights, therefore a starting point is necessary to identify the possible wind power density of the region. In such scenario, Synthetic aperture radars (SAR......) have proven useful. In this study, SAR based dataset- ENVISAT ASAR has been used for Wind Atlas generation. Furthermore, a comparative study has been performed with Global Wind Atlas (GWA) to determine a potential offshore wind farm. Additionally, the annual energy production of that offshore windfarm...

  10. The new European wind atlas

    DEFF Research Database (Denmark)

    Lundtang Petersen, Erik; Troen, Ib; Ejsing Jørgensen, Hans

    2014-01-01

    European Wind Atlas” aiming at reducing overall uncertainties in determining wind conditions; standing on three legs: A data bank from a series of intensive measuring campaigns; a thorough examination and redesign of the model chain from global, mesoscale to microscale models and creation of the wind atlas...... database. Although the project participants will come from the 27 member states it is envisioned that the project will be opened for global participation through test benches for model development and sharing of data – climatologically as well as experimental. Experiences from national wind atlases...... will be utilized, such as the Indian, the South African, the Finnish, the German, the Canadian atlases and others....

  11. A detailed and verified wind resource atlas for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, N.G.; Landberg, L.; Rathmann, O.; Nielsen, M.N. [Risoe National Lab., Roskilde (Denmark); Nielsen, P. [Energy and Environmental Data, Aalberg (Denmark)

    1999-03-01

    A detailed and reliable wind resource atlas covering the entire land area of Denmark has been established. Key words of the methodology are wind atlas analysis, interpolation of wind atlas data sets, automated generation of digital terrain descriptions and modelling of local wind climates. The atlas contains wind speed and direction distributions, as well as mean energy densities of the wind, for 12 sectors and four heights above ground level: 25, 45, 70 and 100 m. The spatial resolution is 200 meters in the horizontal. The atlas has been verified by comparison with actual wind turbine power productions from over 1200 turbines. More than 80% of these turbines were predicted to within 10%. The atlas will become available on CD-ROM and on the Internet. (au)

  12. Developing a wind atlas for South Africa

    Science.gov (United States)

    Lennard, Chris; Hahman, Andrea; Prinsloo, Eric; Mabile, Eugene; Kruger, Andries

    2013-04-01

    The generation of the first verified Wind Atlas for South Africa (WASA) has been a joint undertaking between South African and Danish scientists to provide stakeholders with the best possible information about the wind climate over South Africa. The project is funded by the Royal Danish Embassy, the United Nations Development Programme, the South African Wind Energy Programme and the South African National Energy Development Institute. The project has focused on the western and southern regions of the country and includes a number of activities: 1. An observation campaign during which ten 65 metre masts were erected at selected sites with instruments at 4 levels that have recorded 2 years of data so far, this is ongoing. 2. Mesoscale and micro-scale modelling that consists of two phases. The first phase is complete and used the Karlsruhe Atmospheric Mesoscale Model (KAMM) run at 5 km with the Wind Atlas Analysis and Application Program (WAsP) to generate a wind atlas for the western and southern parts of South Africa. This is a statistical-dynamical method that assumes there is a robust relationship between meteorological situations at the large-scale and meteorological situations at the small-scale. The second phase, to be completed by the end of 2013, will develop a numerical wind atlas using the Weather Research and Forecasting model (WRF) to develop the mesoscale wind climate (4 km resolution) with a continuous 30 year integration from 1980 to 2010. This is a fully dynamical method. The WAsP model will again be used to develop the micro-scale wind climate. 3. An extreme wind climate assessment has identified extreme wind producing synoptic systems, their seasonal and spatial characteristics as well as regions in South Africa particularly prone to extreme wind conditions. 4. New wind climate assessment techniques have been developed in the production of the wind atlas and new techniques to produce the numerical wind atlas will be formulated. 5. Dissemination of

  13. Wind Energy Resource Atlas of Armenia

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.; Heimiller, D.; George, R.

    2003-07-01

    This wind energy resource atlas identifies the wind characteristics and distribution of the wind resource in the country of Armenia. The detailed wind resource maps and other information contained in the atlas facilitate the identification of prospective areas for use of wind energy technologies for utility-scale power generation and off-grid wind energy applications. The maps portray the wind resource with high-resolution (1-km2) grids of wind power density at 50-m above ground. The wind maps were created at the National Renewable Energy Laboratory (NREL) using a computerized wind mapping system that uses Geographic Information System (GIS) software.

  14. Wind Energy Resource Atlas of Oaxaca

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.; Heimiller, D.; George, R.

    2003-08-01

    The Oaxaca Wind Resource Atlas, produced by the National Renewable Energy Laboratory's (NREL's) wind resource group, is the result of an extensive mapping study for the Mexican State of Oaxaca. This atlas identifies the wind characteristics and distribution of the wind resource in Oaxaca. The detailed wind resource maps and other information contained in the atlas facilitate the identification of prospective areas for use of wind energy technologies, both for utility-scale power generation and off-grid wind energy applications.

  15. The UNDP/GEF Baltic wind atlas

    DEFF Research Database (Denmark)

    Rathmann, O.

    2003-01-01

    was running for about two years it was only possible to get one full one-year data series for each site with start time ranging from primo May 2001 to primo October 2001. Themeasured data have been analysed according to the “Wind Atlas Method”, implying cleansing the wind data for nearby terrain effects......, and resulting in regional wind climates or Wind Atlases referring to a number of standard conditions. To the extentpossible measures have been taken to make the regional wind climates represent long-term wind statistics (> 10 year). This was done by using correlation techniques based on reference data from met...... of the three national meteorological institutes. All relevant data files regarding the 8 stations of the project will be available from the wind atlas web of Risø National Laboratory: www.windatlas.dk - with the exception of the private datameasured at Türisalu....

  16. Meso- and Micro-scale Modelling in China: Wind atlas analysis for 12 meteorological stations in NE China (Dongbei)

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Yang, Z.; Hansen, Jens Carsten

    As part of the “Meso-Scale and Micro-Scale Modelling in China” project, also known as the CMA component of the Sino-Danish Wind Energy Development Programme (WED), microscale modelling and analyses have been carried out for 12 meteorological stations in NE China. Wind speed and direction data from...... density (power curve) and calibrated anemometers are confirmed to be prerequisites for reliable predictions; project-specific wind atlas heights are highly recommended....

  17. European Wind Atlas and Wind Resource Research in Denmark

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling

    - from wind measurements at prospective sites to wind tunnel simulations and advanced flow modelling. Among these approaches, the wind atlas methodology - developed at Ris0 National Laboratory over the last 25 years - has gained widespread recognition and is presently considered by many as the industry-standard...

  18. The Numerical Wind Atlas - the KAMM/WAsP Method

    Energy Technology Data Exchange (ETDEWEB)

    Frank, H.P.; Rathmann, O.; Mortensen, N.G.; Landberg, L.

    2001-06-01

    The method of combining the Karlsruhe Atmospheric Mesoscale Model, KAMM, with the Wind Atlas Analysis and Application Program, WAsP, to make local predictions of the wind resource is presented. It combines the advantages of meso-scale modeling - overview over a big region and use of global data bases - with the local prediction capacity of the small-scale model WAsP. Results are presented for Denmark, Ireland, Northern Portugal and Galicia, and the Faroe Islands. Wind atlas files were calculated from wind data simulated with the meso-scale model using model grids with a resolution of 2.5, 5, and 10 km. Using these wind atlas files in WAsP the local prediction of the mean wind does not depend on the grid resolution of the meso-scale model. The local predictions combining KAMM and WAsP are much better than simple interpolation of the wind simulated by KAMM. In addition an investigation was made on the dependence of wind atlas data on the size of WAsP-maps. It is recommended that a topographic map around a site should extend 10 km out from it. If there is a major roughness change like a coast line further away in a frequent wind direction this should be included at even greater distances, perhaps up to 20 km away.

  19. An offshore wind atlas for the Canary Islands

    Energy Technology Data Exchange (ETDEWEB)

    Martin Mederos, A.C. [Zona Eolica Canaria S.A., Veintinueve de Abril, 30, Las Palmas 35007 (Spain); Medina Padron, J.F. [Departamento de Ingenieria Electrica, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas (Spain); Feijoo Lorenzo, A.E. [Departamento de Enxeneria Electrica, Universidade de Vigo, ETSEI, Campus de Lagoas-Marcosende, 36310 Vigo (Spain)

    2011-01-15

    In this paper an analysis of the offshore wind potential in the Canary Islands is presented in the shape of a set of wind maps which constitute an offshore wind atlas. It has been drawn up using data processed from 40 weather stations and satellite. Results from satellite mapping, limited area modelling and mesoscalar modelling have been used by applying the technique known as 'one way nesting'. (author)

  20. Wind Energy Resource Atlas of Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D; Schwartz, M; Scott, G.; Haymes, S.; Heimiller, D.; George, R.

    2001-08-27

    The United States Department of Energy (DOE) and the United States Agency for International Development (USAID) sponsored a project to help accelerate the large-scale use of wind energy technologies in Mongolia through the development of a wind energy resource atlas of Mongolia. DOE's National Renewable Energy Laboratory (NREL) administered and conducted this project in collaboration with USAID and Mongolia. The Mongolian organizations participating in this project were the Scientific, Production, and Trade Corporation for Renewable Energy (REC) and the Institute of Meteorology and Hydrology (IMH). The primary goals of the project were to develop detailed wind resource maps for all regions of Mongolia for a comprehensive wind resource atlas, and to establish a wind-monitoring program to identify prospective sites for wind energy projects and help validate some of the wind resource estimates.

  1. Wind Energy Resource Atlas of Sri Lanka and the Maldives

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.; Heimiller, D.; George, R.

    2003-08-01

    The Wind Energy Resource Atlas of Sri Lanka and the Maldives, produced by the National Renewable Energy Laboratory's (NREL's) wind resource group identifies the wind characteristics and distribution of the wind resource in Sri Lanka and the Maldives. The detailed wind resource maps and other information contained in the atlas facilitate the identification of prospective areas for use of wind energy technologies, both for utility-scale power generation and off-grid wind energy applications.

  2. Development of a numerical wind atlas for South Africa

    DEFF Research Database (Denmark)

    Lennard, Christopher; Hahmann, Andrea N.; Badger, Jake

    2015-01-01

    Two verified wind atlases have been developed for South Africa. The first adopted a statistical-dynamical approach and the second a novel, fully dynamical approach. We verify the atlases against an observational wind atlas generated from three years of data from 10 measurement masts...

  3. Wind Energy Resource Atlas of the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.; Schwartz, M.; George, R.; Haymes, S.; Heimiller, D.; Scott, G.; McCarthy, E.

    2001-03-06

    This report contains the results of a wind resource analysis and mapping study for the Philippine archipelago. The study's objective was to identify potential wind resource areas and quantify the value of those resources within those areas. The wind resource maps and other wind resource characteristic information will be used to identify prospective areas for wind-energy applications.

  4. Satellite winds as a tool for offshore wind resource assessment: The Great Lakes Wind Atlas

    DEFF Research Database (Denmark)

    Doubrawa, Paula; Barthelmie, Rebecca Jane; Pryor, Sara C.

    2015-01-01

    This work presents a new observational wind atlas for the Great Lakes, and proposes a methodology to combine in situ and satellite wind observations for offshore wind resource assessment. Efficient wind energy projects rely on accurate wind resource estimates, which are complex to obtain offshore...... the North American Regional Reanalysis. Generalized wind climates are obtained for each buoy and coastal site with the wind model WAsP, and combined into a single wind speed estimate for the Great Lakes region. The method of classes is used to account for the temporal sparseness in the SAR data set...

  5. The ATLAS Analysis Model

    CERN Multimedia

    Amir Farbin

    The ATLAS Analysis Model is a continually developing vision of how to reconcile physics analysis requirements with the ATLAS offline software and computing model constraints. In the past year this vision has influenced the evolution of the ATLAS Event Data Model, the Athena software framework, and physics analysis tools. These developments, along with the October Analysis Model Workshop and the planning for CSC analyses have led to a rapid refinement of the ATLAS Analysis Model in the past few months. This article introduces some of the relevant issues and presents the current vision of the future ATLAS Analysis Model. Event Data Model The ATLAS Event Data Model (EDM) consists of several levels of details, each targeted for a specific set of tasks. For example the Event Summary Data (ESD) stores calorimeter cells and tracking system hits thereby permitting many calibration and alignment tasks, but will be only accessible at particular computing sites with potentially large latency. In contrast, the Analysis...

  6. Wind Energy Resource Atlas of the Dominican Republic

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.; Schwartz, M.; George, R.; Haymes, S.; Heimiller, D.; Scott, G.; Kline, J.

    2001-10-01

    The Wind Energy Resource Atlas of the Dominican Republic identifies the wind characteristics and the distribution of the wind resource in this country. This major project is the first of its kind undertaken for the Dominican Republic. The information contained in the atlas is necessary to facilitate the use of wind energy technologies, both for utility-scale power generation and off-grid wind energy applications. A computerized wind mapping system developed by NREL generated detailed wind resource maps for the entire country. This technique uses Geographic Information Systems (GIS) to produce high-resolution (1-square kilometer) annual average wind resource maps.

  7. Wind Atlas for South Africa (WASA). Report on Measurements

    DEFF Research Database (Denmark)

    Mabille, Eugéne; Prinsloo, Eric; Mortensen, Niels Gylling

    The key to any good and accurate wind atlas is good quality data. To this end the 1st Verified Numerical Wind Atlas South Africa, for parts of the Northern and Eastern Capes as well as the Western Cape makes use of meteorological data from ten sites, distributed throughout the modelling domain......, to verify the results of the meso-scale modelling. The Measurements work package (WP2) is one of six work packages that collectively make up the Wind Atlas for South Africa (WASA) project. The measurements also provide observed wind climates at the measurement sites, which can be used by micrositing...

  8. Extreme wind atlases of South Africa from global reanalysis data

    DEFF Research Database (Denmark)

    Larsén, Xiaoli Guo; Kruger, Andries; Badger, Jake

    2013-01-01

    Extreme wind atlases of South Africa were developed using three reanalysis data and recently developed approaches. The results are compared with the maps produced using standard wind measurements over the region. It was found that different reanalyses with the same approach provide similar spatial...... distribution of the extreme wind with coarse resolution data giving smaller extreme winds. The CFSR surface winds at 38 km horizontal resolution provides the best spatial distribution of the extreme winds....

  9. Failure Atlas for Rolling Bearings in Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Tallian, T. E.

    2006-01-01

    This Atlas is structured as a supplement to the book: T.E. Tallian: Failure Atlas for Hertz Contact Machine Elements, 2nd edition, ASME Press New York, (1999). The content of the atlas comprises plate pages from the book that contain bearing failure images, application data, and descriptions of failure mode, image, and suspected failure causes. Rolling bearings are a critical component of the mainshaft system, gearbox and generator in the rapidly developing technology of power generating wind turbines. The demands for long service life are stringent; the design load, speed and temperature regimes are demanding and the environmental conditions including weather, contamination, impediments to monitoring and maintenance are often unfavorable. As a result, experience has shown that the rolling bearings are prone to a variety of failure modes that may prevent achievement of design lives. Morphological failure diagnosis is extensively used in the failure analysis and improvement of bearing operation. Accumulated experience shows that the failure appearance and mode of failure causation in wind turbine bearings has many distinguishing features. The present Atlas is a first effort to collect an interpreted database of specifically wind turbine related rolling bearing failures and make it widely available. This Atlas is structured as a supplement to the book: T. E. Tallian: Failure Atlas for Hertz Contact Machine Elements, 2d edition, ASME Press New York, (1999). The main body of that book is a comprehensive collection of self-contained pages called Plates, containing failure images, bearing and application data, and three descriptions: failure mode, image and suspected failure causes. The Plates are sorted by main failure mode into chapters. Each chapter is preceded by a general technical discussion of the failure mode, its appearance and causes. The Plates part is supplemented by an introductory part, describing the appearance classification and failure classification

  10. Wind atlas for Egypt: Measurements, micro- and mesoscale modelling

    DEFF Research Database (Denmark)

    Mortensen, N.G.; Hansen, J.C.; Badger, J.

    2006-01-01

    with SRTM 3 elevation data and satellite imagery, provide the means for immediate WAsP wind resource assessments anywhere in Egypt. In addition to the very high wind resource in the Gulfs of Suez and Aqaba, the wind atlas has discovered a large region in the Western Desert with a fairly high resource...

  11. Wind Atlas of Aegean Sea with SAR data

    DEFF Research Database (Denmark)

    Bingöl, Ferhat; Hasager, Charlotte Bay; Badger, Merete

    2013-01-01

    in satellite radar technologies made it possible to use Synthetic Aperture Radars (SAR) for wind speed and direction measurements at offshore locations. In this study, a new technique of making wind atlases is applied to the region of Aegean Sea is presented. The method has been tested and validated...

  12. Wind energy resource atlas. Volume 4. The Northeast region

    Energy Technology Data Exchange (ETDEWEB)

    Pickering, K.E.; Vilardo, J.M.; Schakenbach, J.T.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1980-09-01

    This atlas of the wind energy resource is composed of introductory and background information, a regional summary of the wind resource, and assessments of the wind resource in each state of the region. Background is presented on how the wind resource is assessed and on how the results of the assessment should be interpreted. A description of the wind resource on a regional scale is then given. The results of the wind energy assessments for each state are assembled in this chapter into an overview and summary of the various features of the regional wind energy resource. An introduction and outline are provided for in the descriptions of the wind resource given for each state. Assessments for individual states are presented. The state wind energy resources are described in greater detail than is the regional wind energy resource, and features of selected stations are discussed. This preface outlines the use and interpretation of the information found in the state chapters.

  13. Wind energy resource atlas. Volume 9. The Southwest Region

    Energy Technology Data Exchange (ETDEWEB)

    Simon, R.L.; Norman, G.T.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1980-11-01

    This atlas of the wind energy resource is composed of introductory and background information, a regional summary of the wind resource, and assessments of the wind resource in Nevada and California. Background on how the wind resource is assessed and on how the results of the assessment should be interpreted is presented. A description of the wind resource on a regional scale is then given. The results of the wind energy assessments for each state are assembled into an overview and summary of the various features of the regional wind energy resource. An introduction and outline to the descriptions of the wind resource given for each state are given. Assessments for individual states are presented as separate chapters. The state wind energy resources are described in greater detail than is the regional wind energy resource, and features of selected stations are discussed.

  14. Analysis Preservation in ATLAS

    CERN Document Server

    Cranmer, Kyle; The ATLAS collaboration; Jones, Roger; South, David

    2015-01-01

    Long before data taking ATLAS established a policy that all analyses need to be preserved. In the initial data-taking period, this has been achieved by various tools and techniques. ATLAS is now reviewing the analysis preservation with the aim to bring coherence and robustness to the process and with a clearer view of the level of reproducibility that is reasonably achievable. The secondary aim is to reduce the load on the analysts. Once complete, this will serve for our internal preservation needs but also provide a basis for any subsequent sharing of analysis results with external parties.

  15. Mesoscale modeling for the Wind Atlas of South Africa (WASA) project

    DEFF Research Database (Denmark)

    Hahmann, Andrea N.; Lennard, Chris; Badger, Jake

    This document reports on the methods used to create and the results of the two numerical wind atlases developed for the Wind Atlas for South Africa (WASA) project. The wind atlases were created using the KAMM-WAsP method and from the output of climate-type simulations of the Weather, Research...

  16. Wind energy resource atlas. Volume 5: the East Central Region

    Energy Technology Data Exchange (ETDEWEB)

    Brode, R.; Stoner, R.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1980-01-01

    This atlas of the wind energy resource is composed of introductory and background information, a regional summary of the wind resource, and assessments of the wind resource in each state of the region. Background is presented on how the wind resource is assessed and on how the results of the assessment should be interpreted. A description of the wind resource on a regional scale is then given. The results of the wind energy assessments for each state are assembled into an overview and summary of the various features of the regional wind energy resource. Assessments for individual states are presented as separate chapters. The state wind energy resources are described in greater detail than is the regional wind energy resource, and features of selected stations are discussed. This preface outlines the use and interpretation of the information found in the state chapters. States include Delaware, Maryland, Kentucky, North Carolina, Tennessee, Virginia, and West Virginia.

  17. Atlas de Recursos Eólicos del Estado de Oaxaca (The Spanish version of Wind Energy Resource Atlas of Oaxaca)

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.; Heimiller, D.; George, R.

    2004-04-01

    The Oaxaca Wind Resource Atlas, produced by the National Renewable Energy Laboratory's (NREL's) wind resource group, is the result of an extensive mapping study for the Mexican State of Oaxaca. This atlas identifies the wind characteristics and distribution of the wind resource in Oaxaca. The detailed wind resource maps and other information contained in the atlas facilitate the identification of prospective areas for use of wind energy technologies, both for utility-scale power generation and off-grid wind energy applications.

  18. South Baltic wind atlas. South Baltic offshore wind energy regions project

    Energy Technology Data Exchange (ETDEWEB)

    Pena, A.; Hahmann, A.; Hasager, C.B.; Bingoel, F.; Karagali, I.; Badger, J.; Badger, M.; Clausen, Niels-Erik

    2011-05-15

    A first version of a wind atlas for the South Baltic Sea has been developed using the WRF mesoscale model and verified by data from tall Danish and German masts. Six different boundary-layer parametrization schemes were evaluated by comparing the WRF results to the observed wind profiles at the masts. The WRF modeling was done in a nested domain of high spatial resolution for 4 years. In addition the long-term wind statistics using the NCAR-NCEP reanalysis data were performed during 30 years to provide basis for a long-term adjustment of the results and the final WRF results include a weighting for the long-term trends variability in the South Baltic Sea. Observations from Earth observing satellites were used to evaluate the spatial resolution of the WRF model results near the surface. The QuikSCAT and the WRF results compared well whereas the Envisat ASAR mean wind map showed some variation to the others. The long-term analysis revealed that the South Baltic Sea has a spatially highly variable wind climate during the 30-years. (Author)

  19. Complex terrain experiments in the New European Wind Atlas

    Science.gov (United States)

    Angelou, N.; Callies, D.; Cantero, E.; Arroyo, R. Chávez; Courtney, M.; Cuxart, J.; Dellwik, E.; Gottschall, J.; Ivanell, S.; Kühn, P.; Lea, G.; Matos, J. C.; Palma, J. M. L. M.; Peña, A.; Rodrigo, J. Sanz; Söderberg, S.; Vasiljevic, N.; Rodrigues, C. Veiga

    2017-01-01

    The New European Wind Atlas project will create a freely accessible wind atlas covering Europe and Turkey, develop the model chain to create the atlas and perform a series of experiments on flow in many different kinds of complex terrain to validate the models. This paper describes the experiments of which some are nearly completed while others are in the planning stage. All experiments focus on the flow properties that are relevant for wind turbines, so the main focus is the mean flow and the turbulence at heights between 40 and 300 m. Also extreme winds, wind shear and veer, and diurnal and seasonal variations of the wind are of interest. Common to all the experiments is the use of Doppler lidar systems to supplement and in some cases replace completely meteorological towers. Many of the lidars will be equipped with scan heads that will allow for arbitrary scan patterns by several synchronized systems. Two pilot experiments, one in Portugal and one in Germany, show the value of using multiple synchronized, scanning lidar, both in terms of the accuracy of the measurements and the atmospheric physical processes that can be studied. The experimental data will be used for validation of atmospheric flow models and will by the end of the project be freely available. This article is part of the themed issue ‘Wind energy in complex terrains’. PMID:28265025

  20. The Wind Atlas for South Africa (WASA): A tool to aid developers and decision makers

    CSIR Research Space (South Africa)

    Mabille, E

    2015-10-01

    Full Text Available Why is a wind atlas important for South Africa? This presentation recommends that a dedicated wind energy measurement programme needs to be undertaken to confirm the true wind energy potential in South Africa....

  1. The numerical wind atlas - the KAMM/WAsP method

    DEFF Research Database (Denmark)

    Frank, H.P.; Rathmann, Ole; Mortensen, Niels Gylling

    2001-01-01

    - with the local prediction capacity of the small-scale model WAsP. Results are presented for Denmark, Ireland, Northern Portugal and Galicia, and the Faroe Islands. Wind atlas files were calculated fromwind data simulated with the mesoscale model using model grids with a resolution of 2.5, 5, and 10 km. Using...

  2. Wind energy resource atlas: Volume 6. The Southeast region

    Energy Technology Data Exchange (ETDEWEB)

    Zabransky, J.; Vilardo, J.M.; Schakenbach, J.T.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-01-01

    The Southeast atlas assimilates six collections of wind resource data: one for the region and one for each of the five states that compose the Southeast region (Alabama, Florida, Georgia, Mississippi, and South Carolina). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and the data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and interannual wind speed and power, and hourly average wind speed for each season. Other graphs present speed, direction and duration frequencies of the wind at these locations.

  3. Wind energy resource atlas. Volume 3. Great Lakes Region

    Energy Technology Data Exchange (ETDEWEB)

    Paton, D.L.; Bass, A.; Smith, D.G.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01

    The Great Lakes Region atlas assimilates six collections of wind resource data, one for the region and one for each of the five states that compose the Great Lakes region: Illinois, Indiana, Michigan, Ohio, Wisconsin. At the state level, features of the climate, topography, and wind resource are discussed in greater detail than in the regional discussion and the data locations on which the assessment is based are mapped. Variations over several time scales in the wind resource at selected stations in each state are shown on graphs of monthly average and interannual wind speed and power, and of hourly average wind speed for each season. Other graphs present speed, direction, and duration frequencies of the wind at these locations.

  4. The selective dynamical downscaling method for extreme-wind atlases

    DEFF Research Database (Denmark)

    Larsén, Xiaoli Guo; Badger, Jake; Hahmann, Andrea N.

    2012-01-01

    and (iii) post-processing. The post-processing generalizes the winds from the mesoscale modelling to standard conditions, i.e. 10-m height over a homogeneous surface with roughness length of 5 cm. The generalized winds are then used to calculate the 50-year wind using the annual maximum method for each...... mesoscale grid point. The generalization of the mesoscale winds through the post-processing provides a framework for data validation and for applying further the mesoscale extreme winds at specific places using microscale modelling. The results are compared with measurements from two areas with different......A selective dynamical downscaling method is developed to obtain extreme-wind atlases for large areas. The method is general, efficient and flexible. The method consists of three steps: (i) identifying storm episodes for a particular area, (ii) downscaling of the storms using mesoscale modelling...

  5. Wind energy resource atlas. Volume 7. The south central region

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, R.L.; Graves, L.F.; Sprankle, A.C.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-03-01

    This atlas of the south central region combines seven collections of wind resource data: one for the region, and one for each of the six states (Arkansas, Kansas, Louisiana, Missouri, Oklahoma, and Texas). At the state level, features of the climate, topography, and wind resource are discussed in greater detail than that provided in the regional discussion, and the data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and interannual wind speed and power, and hourly average wind speed for each season. Other graphs present speed, direction, and duration frequencies of the wind at these locations.

  6. Wind energy resource atlas. Volume 2. The North Central Region

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, D.L.; Hadley, D.L.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01

    The North Central atlas assimilates six collections of wind resource data: one for the region and one for each of the five states that compose the North Central region (Iowa, Minnesota, Nebraska, North Dakota, and South Dakota). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and that data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and international wind speed and power, and hourly average wind speed for each season. Other graphs present speed direction and duration frequencies of the wind at these locations.

  7. ATLAS Distributed Analysis Tools

    CERN Document Server

    Gonzalez de la Hoz, Santiago; Liko, Dietrich

    2008-01-01

    The ATLAS production system has been successfully used to run production of simulation data at an unprecedented scale. Up to 10000 jobs were processed in one day. The experiences obtained operating the system on several grid flavours was essential to perform a user analysis using grid resources. First tests of the distributed analysis system were then performed. In the preparation phase data was registered in the LHC File Catalog (LFC) and replicated in external sites. For the main test, few resources were used. All these tests are only a first step towards the validation of the computing model. The ATLAS management computing board decided to integrate the collaboration efforts in distributed analysis in only one project, GANGA. The goal is to test the reconstruction and analysis software in a large scale Data production using Grid flavors in several sites. GANGA allows trivial switching between running test jobs on a local batch system and running large-scale analyses on the Grid; it provides job splitting a...

  8. Off-shore Wind Atlas of the Central Aegean Sea: A simple comparison of NCEP/NCAR RE-analysis data, QuickSCAT and ENVISAT Synthetic Aperture Radar (SAR) by use of Wind Atlas Method

    DEFF Research Database (Denmark)

    Bingöl, Ferhat; Hasager, Charlotte Bay; Karagali, Ioanna

    2012-01-01

    to high costs, but with the new developments in floating turbine design, it seems that offshore wind parks in deep waters will also be a possibility in the future. Whether on-shore or offshore, the first step of a site assessment is to estimate the wind resources. Usually well-known conventional methods......Offshore wind energy is progressing rapidly in many parts of the world including Europe. While our understanding of offshore wind is growing parallel to that, most of the offshore wind development is located in shallow or transitional waters. Deep, open sea was never preferred by developers due...... are used to produce estimates of wind resources by means of at least one year data from a single or multiple points on the terrain. This criterion is dicult to satisfy in offshore locations where measurements are costly and sparse. Therefore other methods are required (e.g satellite imagery or reanalysis...

  9. Automated Loads Analysis System (ATLAS)

    Science.gov (United States)

    Gardner, Stephen; Frere, Scot; O’Reilly, Patrick

    2013-01-01

    ATLAS is a generalized solution that can be used for launch vehicles. ATLAS is used to produce modal transient analysis and quasi-static analysis results (i.e., accelerations, displacements, and forces) for the payload math models on a specific Shuttle Transport System (STS) flight using the shuttle math model and associated forcing functions. This innovation solves the problem of coupling of payload math models into a shuttle math model. It performs a transient loads analysis simulating liftoff, landing, and all flight events between liftoff and landing. ATLAS utilizes efficient and numerically stable algorithms available in MSC/NASTRAN.

  10. The UNDP/GEF Baltic wind atlas

    Energy Technology Data Exchange (ETDEWEB)

    Rathmann, O.

    2003-11-01

    In the frame of the Regional Baltic Wind Energy Programme, sponsored by the Global Environment Facility through the UNDP, a publicly available wind resource database for the wind-energy relevant areas of the Baltic Countries has been established. A 2-year measurement campaign has been performed based on 7 stations in the coastal area: the 3 Lithuanian sites Kretinga, Vilkyciai and Taurage; the Latvian site Saernate; and the 3 Estonian sites Prangli, Virtsu and Uulu. In addition, private data measured at the Estonian site Tuerisalu was made available to the project. (au)

  11. WRF Mesoscale Pre-Run for the Wind Atlas of Mexico

    DEFF Research Database (Denmark)

    Hahmann, Andrea N.; Pena Diaz, Alfredo; Hansen, Jens Carsten

    This report documents the work performed by DTU Wind Energy for the project “Atlas Eólico Mexicano” or the Wind Atlas of Mexico. This document reports on the methods used in “Pre-run” of the windmapping project for Mexico. The interim mesoscale modeling results were calculated from the output...

  12. Danish extreme wind atlas: Background and methods for a WAsP engineering option

    Energy Technology Data Exchange (ETDEWEB)

    Rathmann, O.; Kristensen, L.; Mann, J. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark); Hansen, S.O. [Svend Ole Hansen ApS, Copenhagen (Denmark)

    1999-03-01

    Extreme wind statistics is necessary design information when establishing wind farms and erecting bridges, buildings and other structures in the open air. Normal mean wind statistics in terms of directional and speed distribution may be estimated by wind atlas methods and are used to estimate e.g. annual energy output for wind turbines. It is the purpose of the present work to extend the wind atlas method to also include the local extreme wind statistics so that an extreme value as e.g. the 50-year wind can be estimated at locations of interest. Together with turbulence estimates such information is important regarding the necessary strength of wind turbines or structures to withstand high wind loads. In the `WAsP Engineering` computer program a flow model, which includes a model for the dynamic roughness of water surfaces, is used to realise such an extended wind atlas method. With basis in an extended wind atlas, also containing extreme wind statistics, this allows the program to estimate extreme winds in addition to mean winds and turbulence intensities at specified positions and heights. (au) EFP-97. 15 refs.

  13. Reliability Analysis of Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2008-01-01

    In order to minimise the total expected life-cycle costs of a wind turbine it is important to estimate the reliability level for all components in the wind turbine. This paper deals with reliability analysis for the tower and blades of onshore wind turbines placed in a wind farm. The limit states......) the reliability level for a wind turbine placed in a wind farm is considered, and wake effects from neighbouring wind turbines is taken into account. An illustrative example with calculation of the reliability for mudline bending of the tower is considered. In the example the design is determined according...

  14. The ATLAS distributed analysis system

    Science.gov (United States)

    Legger, F.; Atlas Collaboration

    2014-06-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of Grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During the first run of the LHC, the ATLAS Distributed Analysis (DA) service has operated stably and scaled as planned. More than 1600 users submitted jobs in 2012, with 2 million or more analysis jobs per week, peaking at about a million jobs per day. The system dynamically distributes popular data to expedite processing and maximally utilize resources. The reliability of the DA service is high and steadily improving; Grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters provides user support and communicates user problems to the sites. Both the user support techniques and the direct feedback of users have been effective in improving the success rate and user experience when utilizing the distributed computing environment. In this contribution a description of the main components, activities and achievements of ATLAS distributed analysis is given. Several future improvements being undertaken will be described.

  15. Implementation Strategy for a Global Solar and Wind Atlas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-01-15

    In July 2009, Major Economies Forum leaders met to prepare for the COP 15 Copenhagen Conference that took place later that year. At this occasion the Major Economies Forum Global Partnership f or low carbon and climate-friendly technology was founded and Technology Action Plans (TAPs) for ten key low-carbon technologies were drafted. At that juncture Denmark, Germany and Spain took on the responsibility for drafting TAPs for Solar and Wind Energy Technologies. The TAPs were then consolidated and presented at COP 15 that would later take place in December in Copenhagen. Since then, countries that led the development of the Action Plans have started their implementation. During a first Clean Energy Ministerial (CEM) in July 2010 in Washington on the invitation of Steven Chu, US Secretary of Energy, several initiatives were launched. Denmark, Germany and Spain took the lead in the implementation of the TAPs for Solar and Wind Technologies and initiated the Multilateral Working Group on Solar and Wind Energy Technologies (MWGSW). Several countries joined the working group in Washington and afterwards. In two international workshops in Bonn (June 2010) and Madrid (November 2010) and in meetings during the first CEM in Washington (July 2010) and the second CEM in Abu Dhabi (April 2011) the Multilateral Working Group made substantial progress in the two initial fields of action: (1) the Development of a Global Solar and Wind Atlas; and (2) the Development of a Long-term Strategy on Joint Capacity Building. Discussion papers on the respective topics were elaborated involving the Working Group's member countries as well as various international institutions. This led to concrete proposals for several pilot activities in both fields of action. After further specifying key elements of the suggested projects in two expert workshops in spring 2011, the Multilateral Working Group convened for a third international workshop in Copenhagen, Denmark, to discuss the project

  16. The ATLAS Distributed Analysis System

    CERN Document Server

    Legger, F; The ATLAS collaboration; Pacheco Pages, A; Stradling, A

    2013-01-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During the first run of the LHC, the ATLAS Distributed Analysis (DA) service has operated stably and scaled as planned. More than 1600 users submitted jobs in 2012, with 2 million or more analysis jobs per week, peaking at about a million jobs per day. The system dynamically distributes popular data to expedite processing and maximally utilize resources. The reliability of the DA service is high but steadily improving; grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters ...

  17. The ATLAS Distributed Analysis System

    CERN Document Server

    Legger, F; The ATLAS collaboration

    2014-01-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During the first run of the LHC, the ATLAS Distributed Analysis (DA) service has operated stably and scaled as planned. More than 1600 users submitted jobs in 2012, with 2 million or more analysis jobs per week, peaking at about a million jobs per day. The system dynamically distributes popular data to expedite processing and maximally utilize resources. The reliability of the DA service is high but steadily improving; grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters ...

  18. Distributed analysis challenges in ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Duckeck, Guenter; Legger, Federica; Mitterer, Christoph Anton; Walker, Rodney [Ludwig-Maximilians-Universitaet Muenchen (Germany)

    2016-07-01

    The ATLAS computing model has undergone massive changes to meet the high luminosity challenge of the second run of the Large Hadron Collider (LHC) at CERN. The production system and distributed data management have been redesigned, a new data format and event model for analysis have been introduced, and common reduction and derivation frameworks have been developed. We report on the impact these changes have on the distributed analysis system, study the various patterns of grid usage for user analysis, focusing on the differences between the first and th e second LHC runs, and measure performances of user jobs.

  19. A high resolution global wind atlas - improving estimation of world wind resources

    DEFF Research Database (Denmark)

    Badger, Jake; Ejsing Jørgensen, Hans

    2011-01-01

    Currently, policy makers and energy planners trying to tackling the challenges of climate change and seeking approaches for climate change mitigation, have no global wind resource dataset appropriate for their pressing needs. The current practice of global energy modellers is to use coarse...... to population centres, electrical transmission grids, terrain types, and protected land areas are important parts of the resource assessment downstream of the generation of wind climate statistics. Related to these issues of integration are the temporal characteristics and spatial correlation of the wind...... resolution reanalysis datasets. This has the serious shortcoming that the wind energy resource is underestimated, as small scale variability of winds is missing. This missing variability is responsible for a large part of the wind resource not being captured in the analysis. Crucially it is the windiest...

  20. Wind turbine reliability analysis

    OpenAIRE

    Pinar Pérez, Jesús María; García Márquez, Fausto Pedro; Tobias, Andrew Mark; Papaelias, Mayorkinos

    2013-01-01

    Against the background of steadily increasing wind power generation worldwide, wind turbine manufacturers are continuing to develop a range of configurations with different combinations of pitch control, rotor speeds, gearboxes, generators and converters. This paper categorizes the main designs, focusing on their reliability by bringing together and comparing data from a selection of major studies in the literature. These are not particularly consistent but plotting failure rates against hour...

  1. NORSEWIND – Mesoscale model derived Wind Atlases for the Irish Sea, the North Sea and the Baltic Sea

    DEFF Research Database (Denmark)

    Berge, Erik; Hasager, Charlotte Bay; Bredesen, Rolv Erlend

    Offshore Wind Atlases based on the meso-scale model WRF are presented and validated in this paper. The Work has been part of the EU-funded project NORSEWIND (Northern Seas Wind Index Database). Validations show that annual average wind speeds and wind-roses at hub-height (100m) are well represent...

  2. Distributed Data Analysis in ATLAS

    CERN Document Server

    Nilsson, P

    2009-01-01

    Data analysis using grid resources is one of the fundamental challenges to be addressed before the start of LHC data taking. The ATLAS detector will produce petabytes of data per year, and roughly one thousand users will need to run physics analyses on this data. Appropriate user interfaces and helper applications have been made available to ensure that the grid resources can be used without requiring expertise in grid technology. These tools enlarge the number of grid users from a few production administrators to potentially all participating physicists. ATLAS makes use of three grid infrastructures for the distributed analysis: the EGEE sites, the Open Science Grid, and NorduGrid. These grids are managed by the gLite workload management system, the PanDA workload management system, and ARC middleware; many sites can be accessed via both the gLite WMS and PanDA. Users can choose between two front-end tools to access the distributed resources. Ganga is a tool co-developed with LHCb to provide a common interfa...

  3. Distributed Data Analysis in ATLAS

    CERN Document Server

    Nilsson, P; The ATLAS collaboration

    2012-01-01

    Data analysis using grid resources is one of the fundamental challenges to be addressed before the start of LHC data taking. The ATLAS detector will produce petabytes of data per year, and roughly one thousand users will need to run physics analyses on this data. Appropriate user interfaces and helper applications have been made available to ensure that the grid resources can be used without requiring expertise in grid technology. These tools enlarge the number of grid users from a few production administrators to potentially all participating physicists. ATLAS makes use of three grid infrastructures for the distributed analysis: the EGEE sites, the Open Science Grid, and NorduGrid. These grids are managed by the gLite workload management system, the PanDA workload management system, and ARC middleware; many sites can be accessed via both the gLite WMS and PanDA. Users can choose between two front-end tools to access the distributed resources. Ganga is a tool co-developed with LHCb to provide a common interfa...

  4. Wind Atlas for South Africa (WASA) Station and Site Description Report

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Hansen, Jens Carsten; Kelly, Mark C.

    As part of the “Wind Atlas for South Africa” project, site inspection trips were carried out by the Council for Scientific and Industrial Research (CSIR) and Risø DTU in April and June of 2011. A total of 10 sites featuring instrumented 60-m masts were visited; the present report summarises...

  5. Dynamics Analysis of Wind Energy Production Development

    Science.gov (United States)

    Berg, V. I.; Zakirzakov, A. G.; Gordievskaya, E. F.

    2017-01-01

    The paper presents the analysis of the introduction experience and dynamics development of the world wind energy production. Calculated the amount of wind energy sources investments and the production capacity growth dynamics of the wind turbines. The studies have shown that the introduction dynamics of new wind energy sources is higher than any other energy source.

  6. Wind Data Analysis and Wind Flow Simulation Over Large Areas

    Directory of Open Access Journals (Sweden)

    Terziev Angel

    2014-03-01

    Full Text Available Increasing the share of renewable energy sources is one of the core policies of the European Union. This is because of the fact that this energy is essential in reducing the greenhouse gas emissions and securing energy supplies. Currently, the share of wind energy from all renewable energy sources is relatively low. The choice of location for a certain wind farm installation strongly depends on the wind potential. Therefore the accurate assessment of wind potential is extremely important. In the present paper an analysis is made on the impact of significant possible parameters on the determination of wind energy potential for relatively large areas. In the analysis the type of measurements (short- and long-term on-site measurements, the type of instrumentation and the terrain roughness factor are considered. The study on the impact of turbulence on the wind flow distribution over complex terrain is presented, and it is based on the real on-site data collected by the meteorological tall towers installed in the northern part of Bulgaria. By means of CFD based software a wind map is developed for relatively large areas. Different turbulent models in numerical calculations were tested and recommendations for the usage of the specific models in flows modeling over complex terrains are presented. The role of each parameter in wind map development is made. Different approaches for determination of wind energy potential based on the preliminary developed wind map are presented.

  7. Wind Atlas for the Gulf of Suez Satellite Imagery and Analyses

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay

    Satellite imagery and data have been used to investigate the spatial distributions of wind speed and some terrain surface characteristics in the Gulf of Suez. The methods and the results are described in three separate sections: 1. “Comparing SAR winds and in-situ winds”. Synthetic Aperture Radar...... classification maps. 3. “Reporting on satellite information for the Wind Atlas for Egypt”. Along-Track Scanning Radiometer (ATSR) data from the European Remote Sensing Satellite (ERS) have been used to map the sea- and land-surface temperatures and albedos....

  8. Mesoscale modelling in China: Risø DTU numerical wind atlas calculation for NE China (Dongbei)

    DEFF Research Database (Denmark)

    Badger, Jake; Larsén, Xiaoli Guo; Hahmann, Andrea N.

    slopes of mountains and large-scale valley features. A comprehensive verification was carried in which the generalized wind climates derived from mesoscale modelling and measurements for nine meteorological stations were compared. A mean absolute error of 8 % for 50 m wind speeds was determined....... The major new aspects of the project were the large number of KAMM/WAsP sensitivity studies, comparison with WRF, and the CMA’s numerical wind atlas method (WERAS). Additionally, the reliability of the input data for the methodology, and the wave-number spectra properties of the output data were...

  9. EnviroAtlas - Annual average potential wind energy resource by 12-digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the annual average potential wind energy resource in kilowatt hours per square kilometer per day for each 12-digit Hydrologic Unit...

  10. Wind farm performance - Power Analysis of a wind turbine

    OpenAIRE

    Esquinas Herrera, Alejandro

    2016-01-01

    Wind conditions from a wind farm situated in Ørland were analyzed based on a ten minute measurements in order to obtain the power and efficiency curves. The results from the analysis were compared with different curves provided from the company Vestas and with theoretical terms. Moreover, it was shown how is affected the power curve of the wind turbine by the wake effect of the other turbines. The different ways of plotting these curves based on wind speed either from the anemometer of the wi...

  11. Wind Energy in Poland - economic analysis of wind farm

    Directory of Open Access Journals (Sweden)

    Gnatowska Renata

    2017-01-01

    Full Text Available Wind power generation is the most dynamically developing branch of renewable energy sector in Poland. The high price of coal and its negative environmental impact result in ever growing support for the renewable energy in the energy sector. Wind power industry produces clean energy, but costs of investments are very high. Process of creating a wind farm is very long and complicated. It requires the knowledge of many disciplines such as law, economics, energetic. The aim of this paper was study the state and the development of the wind power sector, especially wind farm in Poland. The economic analysis on investment in wind farm in Poland according to a new act on renewable energy sources was presented. The subject of this analysis was to estimate profitability of wind farm project 40 MW capacity. The analysis includes the comparison of various support systems - the system of green certificates and the new - auction model on the profitability of investment in wind farm. This aims to show how important is appropriate government support for producers of green energy words.

  12. ATLAS Distributed Data Analysis: performance and challenges

    CERN Document Server

    Fassi, Farida; The ATLAS collaboration

    2015-01-01

    In the LHC operations era the key goal is to analyse the results of the collisions of high-energy particles as a way of probing the fundamental forces of nature. The ATLAS experiment at the LHC at CERN is recording and simulating several 10's of PetaBytes of data per year. The ATLAS Computing Model was designed around the concepts of Grid Computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with this challenge a global network known as the Worldwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. ATLAS accumulated more than 140 PB of data between 2009 and 2014. To analyse these data ATLAS developed, deployed and now operates a mature and stable distributed analysis (DA) service on the WLCG. The service is actively used: more than half a million user jobs run daily on DA resources, submitted by more than 1500 ATLAS physicists. A significant reliability of the...

  13. ATLAS Distributed Data Analysis: challenges and performance

    CERN Document Server

    Fassi, Farida; The ATLAS collaboration

    2015-01-01

    In the LHC operations era the key goal is to analyse the results of the collisions of high-energy particles as a way of probing the fundamental forces of nature. The ATLAS experiment at the LHC at CERN is recording and simulating several 10's of PetaBytes of data per year. The ATLAS Computing Model was designed around the concepts of Grid Computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with this challenge a global network known as the Worldwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. ATLAS accumulated more than 140 PB of data between 2009 and 2014. To analyse these data ATLAS developed, deployed and now operates a mature and stable distributed analysis (DA) service on the WLCG. The service is actively used: more than half a million user jobs run daily on DA resources, submitted by more than 1500 ATLAS physicists. A significant reliability of the...

  14. Wind Energy Resource Atlas. Volume 11. Hawaii and Pacific Islands Region

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, T.A.; Hori, A.M.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01

    This atlas of the wind energy resource is composed of introductory and background information, and assessments of the wind resource in each division of the region. Background on how the wind resource is assessed and on how the results of the assessment should be inerpreted is presented. An introduction and outline to the descriptions of the wind resource for each division are provided. Assessments for individual divisions are presented as separate chapters. Much of the information in the division chapters is given in graphic or tabular form. The sequences for each chapter are similar, but some presentations used for Hawaii are inappropriate or impractical for presentation with the Pacific Islands. Hawaii chapter figure and tables are cited below and appropriate Pacific Islands figure and table numbers are included in brackets ().

  15. On the Fatigue Analysis of Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, Herbert J.

    1999-06-01

    Modern wind turbines are fatigue critical machines that are typically used to produce electrical power from the wind. Operational experiences with these large rotating machines indicated that their components (primarily blades and blade joints) were failing at unexpectedly high rates, which led the wind turbine community to develop fatigue analysis capabilities for wind turbines. Our ability to analyze the fatigue behavior of wind turbine components has matured to the point that the prediction of service lifetime is becoming an essential part of the design process. In this review paper, I summarize the technology and describe the ''best practices'' for the fatigue analysis of a wind turbine component. The paper focuses on U.S. technology, but cites European references that provide important insights into the fatigue analysis of wind turbines.

  16. Wind Atlas for South Africa (WASA) Observational wind atlas for 10 met. stations in Northern, Western and Eastern Cape provinces

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Hansen, Jens Carsten; Kelly, Mark C.

    Program (WAsP 11). The wind-climatological inputs are the observed wind climates derived from the WAsP Climate Analyst. Topographical inputs are elevation maps constructed from SRTM 3 data and roughness length maps constructed from SWBD data and Google Earth satellite imagery. Summaries are given...

  17. Advanced Technology Lifecycle Analysis System (ATLAS)

    Science.gov (United States)

    O'Neil, Daniel A.; Mankins, John C.

    2004-01-01

    Developing credible mass and cost estimates for space exploration and development architectures require multidisciplinary analysis based on physics calculations, and parametric estimates derived from historical systems. Within the National Aeronautics and Space Administration (NASA), concurrent engineering environment (CEE) activities integrate discipline oriented analysis tools through a computer network and accumulate the results of a multidisciplinary analysis team via a centralized database or spreadsheet Each minute of a design and analysis study within a concurrent engineering environment is expensive due the size of the team and supporting equipment The Advanced Technology Lifecycle Analysis System (ATLAS) reduces the cost of architecture analysis by capturing the knowledge of discipline experts into system oriented spreadsheet models. A framework with a user interface presents a library of system models to an architecture analyst. The analyst selects models of launchers, in-space transportation systems, and excursion vehicles, as well as space and surface infrastructure such as propellant depots, habitats, and solar power satellites. After assembling the architecture from the selected models, the analyst can create a campaign comprised of missions spanning several years. The ATLAS controller passes analyst specified parameters to the models and data among the models. An integrator workbook calls a history based parametric analysis cost model to determine the costs. Also, the integrator estimates the flight rates, launched masses, and architecture benefits over the years of the campaign. An accumulator workbook presents the analytical results in a series of bar graphs. In no way does ATLAS compete with a CEE; instead, ATLAS complements a CEE by ensuring that the time of the experts is well spent Using ATLAS, an architecture analyst can perform technology sensitivity analysis, study many scenarios, and see the impact of design decisions. When the analyst is

  18. Wind Atlas for South Africa (WASA) Observational wind atlas for 10 met. stations in Northern, Western and Eastern Cape provinces

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Hansen, Jens Carsten; Kelly, Mark C.

    Program (WAsP 11). The windclimatological inputs are the observed wind climates derived from the WAsP Climate Analyst. Topographical inputs are elevation maps constructed from SRTM 3 data and rough-ness length maps constructed from SWBD data and Google Earth satellite imagery. Summaries are given...

  19. Offshore Wind Market and Economic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, Bruce Duncan [Navigant Consulting, Inc., Chicago, IL (United States)

    2014-08-27

    This report is the third annual assessment of the U.S. offshore wind market. It includes the following major sections: Section 1: key data on developments in the offshore wind technology sector and the global development of offshore wind projects, with a particular focus on progress in the United States; Section 2: analysis of policy developments at the federal and state levels that have been effective in advancing offshore wind deployment in the United States; Section 3: analysis of actual and projected economic impact, including regional development and job creation; Section 4: analysis of developments in relevant sectors of the economy with the potential to affect offshore wind deployment in the United States

  20. Sri Lanka Wind Farm Analysis and Site Selection Assistance

    Energy Technology Data Exchange (ETDEWEB)

    Young, M.; Vilhauer, R.

    2003-08-01

    The United States Department of Energy (DOE), through the National Renewable Energy Laboratory (NREL), has been working in partnership with the U.S. Agency for International Development (USAID) in an on-going process to quantify the Sri Lanka wind energy potential and foster wind energy development. Work to date includes completion of the NREL wind atlas for Sri Lanka. In addition, the Ceylon Electricity Board (CEB) has conducted a wind resource assessment of several areas of the country and has successfully completed and is currently operating a 3-MW pilot wind project. A review of the work completed to date indicates that additional activities are necessary to provide Sri Lanka with the tools necessary to identify the best wind energy development opportunities. In addition, there is a need to identify key policy, regulatory, business and infrastructure issues that affect wind energy development and to recommend steps to encourage and support wind power development and investment.

  1. Atlas transmission line breakdown analysis

    CERN Document Server

    Nielsen, K E; Ballard, E O; Elizondo, J M; Gribble, R F; McCuistian, B T; Parsons, W M

    1999-01-01

    The Atlas facility will use 24 radially converging, vertically oriented and tapered, oil insulated, triplate transmission lines between the Marx generators and the central load region. Among the requirements of the transmission lines are low inductance and high reliability. The inter-conductor gap is nominally 2 cm and the lines taper from a height of 1.75 m at the Marx end to 0.32 m at the output end. The aluminum conductors, held together by 20 insulating spacers, are assembled and inserted as a unit into radial oil-filled steel tanks. The negative, high-voltage, center conductor is 2.54-cm thick and the outer ground conductors are 1.59-cm thick. All 24 triplate transmission lines connect to a transition section at near 1 m radius that couples the transmission lines to a disk/conical solid- dielectric-insulated power flow channel transmission line terminating at the load. Peak operating voltage on the lines can be as high as 240 kV with an effective stress time of 0.8 mu s. Testing of small sections of the ...

  2. Wind Atlas for South Africa (WASA): Project overview and status - Wind Power Africa Conference 2010

    CSIR Research Space (South Africa)

    Szewczuk, S

    2010-05-01

    Full Text Available • Activities ongoing – Mast transport to site and erection – Instrumentation • Data acquisition from all masts expected to start July 2010 • RODEO, web and data availability for public access expected to start September 2010 WP2 method overview Wind... via GSM • Acquisition, QA, calibration and database organisation and web publishing by RODEO at CSIR • Web www.wasa.csir.co.za • Graphs daily • Data files monthly The wind measurement stations were designed with a view to • Meeting IEC...

  3. Wind atlas for South Africa: wind measurements and micro-scale modelling

    CSIR Research Space (South Africa)

    Szewczuk, S

    2010-08-01

    Full Text Available Africa is intended to accelerate the investment in wind energy in South Africa. This is in line with government’s objectives of reducing green house gases and diversifying our energy supply and also developing human capacity to support the emerging...

  4. Dynamic Resonance Sensitivity Analysis in Wind Farms

    DEFF Research Database (Denmark)

    Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei

    2017-01-01

    Unlike conventional power systems, where resonance frequencies are mainly determined by passive impedances, wind farms present a more complex situation, where the control systems of the power electronic converters introduce also active impedances. This paper presents an approach to find...... the resonance frequencies of wind farms by considering both active and passive impedances and to identify which bus of the wind farm has more contribution to resonance frequencies. In the approach, a wind farm is introduced as a Multi-Input Multi-Output (MIMO) dynamic system and the bus Participation Factors...... (PFs) are calculated by critical eigenvalue sensitivity analysis versus the entries of the MIMO matrix. The PF analysis locates the most exciting bus of the resonances, where can be the best location to install the passive or active filters to reduce the harmonic resonance problems. Time...

  5. Complex terrain wind resource estimation with the wind-atlas method: Prediction errors using linearized and nonlinear CFD micro-scale models

    DEFF Research Database (Denmark)

    Troen, Ib; Bechmann, Andreas; Kelly, Mark C.

    2014-01-01

    flow model (CFD) for a number of sites in very complex terrain (large terrain slopes). We first briefly describe the Wind Atlas methodology as implemented in WAsP and the specifics of the “classical” model setup and the new setup allowing the use of the CFD computation engine. We discuss some known...... shortcomings of the linear orographic flow model (BZ) and possible modifications that could be considered, including the established RIX method....

  6. Analysis of counter-rotating wind turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Zakkam, Vinod Arun Kumar; Sørensen, Jens Nørkær

    2007-01-01

    -Stokes code EllipSys3D. The analysis shows that the Annual Energy Production can be increased to about 43.5 %, as compared to a wind turbine with a single rotor. In order to determine the optimal settings of the CRWT turbine, parameters such as distance between two rotors and rotational speed have been......This paper presents a study on the performance of a wind turbine with two counter-rotating (CRWT) rotors. The characteristics of the two counter-rotating rotors are on a 3-bladed Nordtank 500 kW rotor. The analysis has been carried out by using an Actuator Line technique implemented in the Navier...

  7. Analysis list - ChIP-Atlas | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available target gene analysis and colocalization analysis. See details here: https://github.com/inutano/chip-atlas/w...peline. Data analysis method See details of data processing here: https://github.com/inutano/chip-atlas/wiki

  8. The Cerefy Neuroradiology Atlas: a Talairach-Tournoux atlas-based tool for analysis of neuroimages available over the internet.

    Science.gov (United States)

    Nowinski, Wieslaw L; Belov, Dmitry

    2003-09-01

    The article introduces an atlas-assisted method and a tool called the Cerefy Neuroradiology Atlas (CNA), available over the Internet for neuroradiology and human brain mapping. The CNA contains an enhanced, extended, and fully segmented and labeled electronic version of the Talairach-Tournoux brain atlas, including parcelated gyri and Brodmann's areas. To our best knowledge, this is the first online, publicly available application with the Talairach-Tournoux atlas. The process of atlas-assisted neuroimage analysis is done in five steps: image data loading, Talairach landmark setting, atlas normalization, image data exploration and analysis, and result saving. Neuroimage analysis is supported by a near-real-time, atlas-to-data warping based on the Talairach transformation. The CNA runs on multiple platforms; is able to process simultaneously multiple anatomical and functional data sets; and provides functions for a rapid atlas-to-data registration, interactive structure labeling and annotating, and mensuration. It is also empowered with several unique features, including interactive atlas warping facilitating fine tuning of atlas-to-data fit, navigation on the triplanar formed by the image data and the atlas, multiple-images-in-one display with interactive atlas-anatomy-function blending, multiple label display, and saving of labeled and annotated image data. The CNA is useful for fast atlas-assisted analysis of neuroimage data sets. It increases accuracy and reduces time in localization analysis of activation regions; facilitates to communicate the information on the interpreted scans from the neuroradiologist to other clinicians and medical students; increases the neuroradiologist's confidence in terms of anatomy and spatial relationships; and serves as a user-friendly, public domain tool for neuroeducation. At present, more than 700 users from five continents have subscribed to the CNA.

  9. Advanced Technology Lifecycle Analysis System (ATLAS) Technology Tool Box (TTB)

    Science.gov (United States)

    Doyle, Monica; ONeil, Daniel A.; Christensen, Carissa B.

    2005-01-01

    The Advanced Technology Lifecycle Analysis System (ATLAS) is a decision support tool designed to aid program managers and strategic planners in determining how to invest technology research and development dollars. It is an Excel-based modeling package that allows a user to build complex space architectures and evaluate the impact of various technology choices. ATLAS contains system models, cost and operations models, a campaign timeline and a centralized technology database. Technology data for all system models is drawn from a common database, the ATLAS Technology Tool Box (TTB). The TTB provides a comprehensive, architecture-independent technology database that is keyed to current and future timeframes.

  10. Applied modal analysis of wind turbine blades

    Energy Technology Data Exchange (ETDEWEB)

    Broen Pedersen, H.; Dahl Kristensen, O.J.

    2003-02-01

    In this project modal analysis has been used to determine the natural frequencies, damping and the mode shapes for wind turbine blades. Different methods to measure the position and adjust the direction of the measuring points are discussed. Different equipment for mounting the accelerometers are investigated and the most suitable are chosen. Different excitation techniques are tried during experimental campaigns. After a discussion the pendulum hammer were chosen, and a new improved hammer was manufactured. Some measurement errors are investigated. The ability to repeat the measured results is investigated by repeated measurement on the same wind turbine blade. Furthermore the flexibility of the test set-up is investigated, by use of accelerometers mounted on the flexible adapter plate during the measurement campaign. One experimental campaign investigated the results obtained from a loaded and unloaded wind turbine blade. During this campaign the modal analysis are performed on a blade mounted in a horizontal and a vertical position respectively. Finally the results obtained from modal analysis carried out on a wind turbine blade are compared with results obtained from the Stig Oeyes blade{sub E}V1 program. (au)

  11. Analysis of loads on wind turbines in complex terrain wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, K.; Markkilde Petersen, S. (The Test Station for Wind Turbines, Risoe National laboratory, Roskilde (Denmark)); Lading, P.; Sangill, O. (Windgineering ApS, Centre for Advanced Technology, Roskilde (Denmark))

    1992-09-01

    This paper describes structural load analysis of wind turbines erected in wind farms in complex terrain. The analysis is based on measurements on two Danwin turbines in Alta Mesa, San Gorgonia Pass California. The wind climate in wind farms in mountainous terrain differs significantly from wind conditions in homogeneous terrain, and this influences the turbine loading. Special attention is paid to characterize this difference by the wind turbulence characteristics. The power spectrum of the longitudinal turbulence component is investigated, and the measured wind conditions are analyzed in relation to what is expected for the free flow in homogenous terrain. The structural response is characterized by the main loads, i.e. blade and rotor loads. The response is related to the actual wind inflow. The relative importance of the deterministic and stochastic load-generating mechanisms is investigated. The azimuthal variations of the loads are calculated, and the load signals are spectral analyzed. The fatigue loads are estimated by Rainflow counting at different operational conditions and the resulting lifetime accumulated load spectra are calculated on the basis of wind distribution and turbulence level. The differences between lifetime fatigue loads seen in wind farms in complex terrain and wind farms in homogenous terrain are discussed. The accumulated load spectra are compared to the Danish Standard for Loads and Safety of Wind Turbines, and extensions to this standard are suggested for wind turbines erected in wind farm clusters. (au) (17 refs.).

  12. Evolution of User Analysis on the Grid in ATLAS

    CERN Document Server

    Legger, Federica; The ATLAS collaboration

    2016-01-01

    More than one thousand physicists analyse data collected by the ATLAS experiment at the Large Hadron Collider (LHC) at CERN through 150 computing facilities around the world. Efficient distributed analysis requires optimal resource usage and the interplay of several factors: robust grid and software infrastructures, system capability to adapt to different workloads. The continuous automatic validation of grid sites and the user support provided by a dedicated team of expert shifters have been proven to provide a solid distributed analysis system for ATLAS users. Based on the experience from the first run of the LHC, substantial improvements to the ATLAS computing system have been made to optimize both production and analysis workflows. These include the re-design of the production and data management systems, a new analysis data format and event model, and the development of common reduction and analysis frameworks. The impact of such changes on the distributed analysis system is evaluated. More than 100 mill...

  13. Dynamic Response Analysis of an Offshore Wind Turbine

    OpenAIRE

    Li, Yu

    2011-01-01

    The offshore wind power is an attractive renewable energy resource. To improve the wind power generation capacity, there is a strong desire for offshore wind turbine to go to deep waters. For offshore fixed wind turbine, stronger foundation like jacket structure has a good applicability for deeper water depth. A 70-meters jacket substructure for offshore wind turbine is designed. This thesis focuses on the dynamic structural response analysis of this jacket substructure, with a particular foc...

  14. Advanced Coal Wind Hybrid: Economic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Phadke, Amol; Goldman, Charles; Larson, Doug; Carr, Tom; Rath, Larry; Balash, Peter; Yih-Huei, Wan

    2008-11-28

    Growing concern over climate change is prompting new thinking about the technologies used to generate electricity. In the future, it is possible that new government policies on greenhouse gas emissions may favor electric generation technology options that release zero or low levels of carbon emissions. The Western U.S. has abundant wind and coal resources. In a world with carbon constraints, the future of coal for new electrical generation is likely to depend on the development and successful application of new clean coal technologies with near zero carbon emissions. This scoping study explores the economic and technical feasibility of combining wind farms with advanced coal generation facilities and operating them as a single generation complex in the Western US. The key questions examined are whether an advanced coal-wind hybrid (ACWH) facility provides sufficient advantages through improvements to the utilization of transmission lines and the capability to firm up variable wind generation for delivery to load centers to compete effectively with other supply-side alternatives in terms of project economics and emissions footprint. The study was conducted by an Analysis Team that consists of staff from the Lawrence Berkeley National Laboratory (LBNL), National Energy Technology Laboratory (NETL), National Renewable Energy Laboratory (NREL), and Western Interstate Energy Board (WIEB). We conducted a screening level analysis of the economic competitiveness and technical feasibility of ACWH generation options located in Wyoming that would supply electricity to load centers in California, Arizona or Nevada. Figure ES-1 is a simple stylized representation of the configuration of the ACWH options. The ACWH consists of a 3,000 MW coal gasification combined cycle power plant equipped with carbon capture and sequestration (G+CC+CCS plant), a fuel production or syngas storage facility, and a 1,500 MW wind plant. The ACWH project is connected to load centers by a 3,000 MW

  15. Pre-Test Analysis of Major Scenarios for ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Euh, Dong-Jin; Choi, Ki-Yong; Park, Hyun-Sik; Kwon, Tae-Soon

    2007-02-15

    A thermal-hydraulic integral effect test facility, ATLAS was constructed at the Korea Atomic Energy Research Institute (KAERI). The ATLAS is a 1/2 reduced height and 1/288 volume scaled test facility based on the design features of the APR1400. The simulation capability of the ATLAS for major design basis accidents (DBAs), including a large-break loss-of-coolant (LBLOCA), DVI line break and main steam line break (MSLB) accidents, is evaluated by the best-estimate system code, MARS, with the same control logics, transient scenarios and nodalization scheme. The validity of the applied scaling law and the thermal-hydraulic similarity between the ATLAS and the APR1400 for the major design basis accidents are assessed. It is confirmed that the ATLAS has a capability of maintaining an overall similarity with the reference plant APR1400 for the major design basis accidents considered in the present study. However, depending on the accident scenarios, there are some inconsistencies in certain thermal hydraulic parameters. It is found that the inconsistencies are mainly due to the reduced power effect and the increased stored energy in the structure. The present similarity analysis was successful in obtaining a greater insight into the unique design features of the ATLAS and would be used for developing the optimized experimental procedures and control logics.

  16. Analysis of wind energy generation possibilities with various rotor types at disadvantageous wind condition zones

    Science.gov (United States)

    Bieniek, Andrzej

    2017-10-01

    The paper describe possibilities of energy generation using various rotor types but especially with multi-blade wind engine operates in the areas with unfavourable wind condition. The paper presents also wind energy conversion estimation results presented based on proposed solution of multi-blade wind turbine of outer diameter of 4 m. Based on the wind distribution histogram from the disadvantage wind condition zones (city of Basel) and taking into account design and estimated operating indexes of the considered wind engine rotor an annual energy generation was estimated. Also theoretical energy generation using various types of wind turbines operates at disadvantage wind conditions zones were estimated and compared. The conducted analysis shows that introduction of multi-blade wind rotor instead of the most popular 3- blades or vertical axis rotors results of about 5% better energy generation. Simultaneously there are energy production also at very disadvantages wind condition at wind speed lower then 4 m s-1. Based on considered construction of multi-blade wind engine the rise of rotor mounting height from 10 to 30 m results with more then 300 % better results in terms of electric energy generation.

  17. Analysis of wind energy generation possibilities with various rotor types at disadvantageous wind condition zones

    Directory of Open Access Journals (Sweden)

    Bieniek Andrzej

    2017-01-01

    Full Text Available The paper describe possibilities of energy generation using various rotor types but especially with multi-blade wind engine operates in the areas with unfavourable wind condition. The paper presents also wind energy conversion estimation results presented based on proposed solution of multi-blade wind turbine of outer diameter of 4 m. Based on the wind distribution histogram from the disadvantage wind condition zones (city of Basel and taking into account design and estimated operating indexes of the considered wind engine rotor an annual energy generation was estimated. Also theoretical energy generation using various types of wind turbines operates at disadvantage wind conditions zones were estimated and compared. The conducted analysis shows that introduction of multi-blade wind rotor instead of the most popular 3- blades or vertical axis rotors results of about 5% better energy generation. Simultaneously there are energy production also at very disadvantages wind condition at wind speed lower then 4 ms-1. Based on considered construction of multi-blade wind engine the rise of rotor mounting height from 10 to 30 m results with more then 300 % better results in terms of electric energy generation.

  18. ATLAS

    Data.gov (United States)

    Federal Laboratory Consortium — ATLAS is a particle physics experiment at the Large Hadron Collider at CERN, the European Organization for Nuclear Research. Scientists from Brookhaven have played...

  19. Winding around the winding number in topology, geometry, and analysis

    CERN Document Server

    Roe, John

    2015-01-01

    The winding number is one of the most basic invariants in topology. It measures the number of times a moving point P goes around a fixed point Q, provided that P travels on a path that never goes through Q and that the final position of P is the same as its starting position. This simple idea has far-reaching applications. The reader of this book will learn how the winding number can help us show that every polynomial equation has a root (the fundamental theorem of algebra), guarantee a fair division of three objects in space by a single planar cut (the ham sandwich theorem), explain why ever

  20. SUBSONIC WIND TUNNEL PERFORMANCE ANALYSIS SOFTWARE

    Science.gov (United States)

    Eckert, W. T.

    1994-01-01

    This program was developed as an aid in the design and analysis of subsonic wind tunnels. It brings together and refines previously scattered and over-simplified techniques used for the design and loss prediction of the components of subsonic wind tunnels. It implements a system of equations for determining the total pressure losses and provides general guidelines for the design of diffusers, contractions, corners and the inlets and exits of non-return tunnels. The algorithms used in the program are applicable to compressible flow through most closed- or open-throated, single-, double- or non-return wind tunnels or ducts. A comparison between calculated performance and that actually achieved by several existing facilities produced generally good agreement. Any system through which air is flowing which involves turns, fans, contractions etc. (e.g., an HVAC system) may benefit from analysis using this software. This program is an update of ARC-11138 which includes PC compatibility and an improved user interface. The method of loss analysis used by the program is a synthesis of theoretical and empirical techniques. Generally, the algorithms used are those which have been substantiated by experimental test. The basic flow-state parameters used by the program are determined from input information about the reference control section and the test section. These parameters were derived from standard relationships for compressible flow. The local flow conditions, including Mach number, Reynolds number and friction coefficient are determined for each end of each component or section. The loss in total pressure caused by each section is calculated in a form non-dimensionalized by local dynamic pressure. The individual losses are based on the nature of the section, local flow conditions and input geometry and parameter information. The loss forms for typical wind tunnel sections considered by the program include: constant area ducts, open throat ducts, contractions, constant

  1. Early experience with the Run 2 ATLAS analysis model

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00212857; The ATLAS collaboration

    2016-01-01

    During the Long shutdown of the LHC, the ATLAS collaboration overhauled its analysis model based on experience gained during Run 1. The main components are a new analysis format and Event Data Model which can be read directly by ROOT, as well as a "Derivation Framework" that takes the Petabyte-scale output from ATLAS reconstruction and produces smaller samples targeted at specific analyses, using the central production system. We will discuss the technical and operational aspects of this new system and review its performance during the first year of 13 TeV data taking.

  2. Evolution of user analysis on the grid in ATLAS

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00218990; The ATLAS collaboration; Dewhurst, Alastair

    2016-01-01

    More than one thousand physicists analyse data collected by the ATLAS experiment at the Large Hadron Collider (LHC) at CERN through 150 computing facilities around the world. Efficient distributed analysis requires optimal resource usage and the interplay of several factors: robust grid and software infrastructures, and system capability to adapt to different workloads. The continuous automatic validation of grid sites and the user support provided by a dedicated team of expert shifters have been proven to provide a solid distributed analysis system for ATLAS users. Typical user workflows on the grid, and their associated metrics, are discussed. Measurements of user job performance and typical requirements are also shown.

  3. Evolution of user analysis on the grid in ATLAS

    Science.gov (United States)

    Dewhurst, A.; Legger, F.; ATLAS Collaboration

    2017-10-01

    More than one thousand physicists analyse data collected by the ATLAS experiment at the Large Hadron Collider (LHC) at CERN through 150 computing facilities around the world. Efficient distributed analysis requires optimal resource usage and the interplay of several factors: robust grid and software infrastructures, and system capability to adapt to different workloads. The continuous automatic validation of grid sites and the user support provided by a dedicated team of expert shifters have been proven to provide a solid distributed analysis system for ATLAS users. Typical user workflows on the grid, and their associated metrics, are discussed. Measurements of user job performance and typical requirements are also shown.

  4. Small-scale wind power design, analysis, and environmental impacts

    CERN Document Server

    Abraham, John P

    2014-01-01

    In today's world, clean and robust energy sources are being sought to provide power to residences, commercial operations, and manufacturing enterprises. Among the most appealing energy sources is wind power-with its high reliability and low environmental impact. Wind power's rapid penetration into markets throughout the world has taken many forms, and this book discusses the types of wind power, as well as the appropriate decisions that need to be made regarding wind power design, testing, installation, and analysis. Inside, the authors detail the design of various small-wind systems including horizontal-axis wind turbines (HAWTs) and vertical-axis wind turbines (VAWTs). The design of wind turbines takes advantage of many avenues of investigation, all of which are included in the book. Analytical methods that have been developed over the past few decades are major methods used for design. Alternatively, experimentation (typically using scaled models in wind tunnels) and numerical simulation (using modern comp...

  5. Smart Wind Turbine : Analysis and Autonomous Flap

    NARCIS (Netherlands)

    Bernhammer, L.O.

    2015-01-01

    Wind turbines convert kinetic energy of the wind into electrical energy. Unfortunately, this process is everything but constant, as the wind source shows large fluctuations with high and low frequencies. This turbulence, together with the wind shear and yawed inflow, excites the turbine structure,

  6. CFD analysis of a Darrieus wind turbine

    Science.gov (United States)

    Niculescu, M. L.; Cojocaru, M. G.; Pricop, M. V.; Pepelea, D.; Dumitrache, A.; Crunteanu, D. E.

    2017-07-01

    The Darrieus wind turbine has some advantages over the horizontal-axis wind turbine. Firstly, its tip speed ratio is lower than that of the horizontal-axis wind turbine and, therefore, its noise is smaller, privileging their placement near populated areas. Secondly, the Darrieus wind turbine does needs no orientation mechanism with respect to wind direction in contrast to the horizontal-axis wind turbine. However, the efficiency of the Darrieus wind turbine is lower than that of the horizontal-axis wind turbine since its aerodynamics is much more complex. With the advances in computational fluids and computers, it is possible to simulate the Darrieus wind turbine more accurately to understand better its aerodynamics. For these reasons, the present papers deals with the computational aerodynamics of a Darrieus wind turbine applying the state of the art of CFD methods (anisotropic turbulence models, transition from laminar to turbulent, scale adaptive simulation) to better understand its unsteady behavior.

  7. Analysis of horizontal axis wind turbine blade using CFD | Nigam ...

    African Journals Online (AJOL)

    Blade is very essential part of HAWT (horizontal axis wind turbine). Forces for Lift and drag on the blade has an important role in the wind turbine performance. The main purpose of this work is to perform CFD analysis of a blade and airfoil of wind turbine using k-ω SST model. In this present study NACA 634 -221 airfoil ...

  8. Full scale experimental analysis of wind direction changes (EOD)

    DEFF Research Database (Denmark)

    Hansen, Kurt Schaldemose

    2007-01-01

    the magnitudes of a joint gust event defined by a simultaneously wind speed- and direction change in order to obtain an indication of the validity of the magnitudes specified in the IEC code. The analysis relates to pre-specified recurrence periods and is based on full-scale wind field measurements. The wind...

  9. Auto-correlation analysis of ocean surface wind vectors

    Indian Academy of Sciences (India)

    The nature of the inherent temporal variability of surface winds is analyzed by comparison of winds obtained through different measurement methods. In this work, an auto-correlation analysis of a time series data of surface winds measured in situ by a deep water buoy in the Indian Ocean has been carried out. Hourly time ...

  10. Continuous software quality analysis for the ATLAS experiment

    CERN Document Server

    Washbrook, Andrew; The ATLAS collaboration

    2017-01-01

    The software for the ATLAS experiment on the Large Hadron Collider at CERN has evolved over many years to meet the demands of Monte Carlo simulation, particle detector reconstruction and data analysis. At present over 3.8 million lines of C++ code (and close to 6 million total lines of code) are maintained by an active worldwide developer community. In order to run the experiment software efficiently at hundreds of computing centres it is essential to maintain a high level of software quality standards. The methods proposed to improve software quality practices by incorporating checks into the new ATLAS software build infrastructure.

  11. Institutions Function and Failure Statistic and Analysis of Wind Turbine

    Science.gov (United States)

    yang, Ma; Chengbing, He; Xinxin, Feng

    Recently,with install capacity of wind turbines increases continuously, the wind power consisting of operation,research on reliability,maintenance and rapair will be developed into a key point..Failure analysis can support operation,management of spare components and accessories in wind plants,maintenance and repair of wind turbines.In this paper,with the eye of wind plants'structure and function,statistic and analysis the common fault of each part of the plant,and then find out the faults law, faults cause and fault effect,from which put forward the corresponding measures.

  12. ATLAS

    CERN Multimedia

    2002-01-01

    Barrel and END-CAP Toroids In order to produce a powerful magnetic field to bend the paths of the muons, the ATLAS detector uses an exceptionally large system of air-core toroids arranged outside the calorimeter volumes. The large volume magnetic field has a wide angular coverage and strengths of up to 4.7tesla. The toroids system contains over 100km of superconducting wire and has a design current of 20 500 amperes. (ATLAS brochure: The Technical Challenges)

  13. Analysis of Wind Energy Potential and Optimum Wind Blade Design for Jamshoro Wind Corridor

    Directory of Open Access Journals (Sweden)

    SYED UMAID ALI

    2017-10-01

    Full Text Available Pakistan is facing energy crisis since last decade. This crisis can be effectively handled by utilizing alternative energy resources. Pakistan has a huge wind energy potential of about 50,000MW. The contribution of costal area of Sindh, Pakistan in the total wind energy potential is about 43000MW. The Jamshoro wind corridor has the highest wind potential of all coastal areas of Sindh. In this paper a wind blade design has been developed and optimized for Jamshoro wind corridor. The theoretical blade design include the airfoil selection, appropriate chord length selection and optimization of twist angle. The designed blade has been analyzed using Q-blade. Considering the Jamshorowind conditions, blade of around 43 meters have been designed and optimized theoretically. Then the theoretical design is also been checked and verified in Q-blade. Theoretical optimization includes using different combinations of NACA profiles and using exhaustive iterative method to get optimized twist angle. This ensures the design with maximum power output with respect to wind speed of Jamshoro. For low wind speeds, theoretical results and simulated results in Q-blade were almost same but for high wind speeds, results were significantly different due to limitation of iterations in theoretical design

  14. Analysis of empty ATLAS pilot jobs

    CERN Document Server

    Love, Peter; The ATLAS collaboration

    2016-01-01

    The pilot model used by the ATLAS production system has been in use for many years. The model has proven to be a success with many advantages over push models. However one of the negative side-effects of using a pilot model is the presence of 'empty pilots' running on sites which consume a small amount of walltime and not running a useful payload job. The impact on a site can be significant with previous studies showing a total 0.5% walltime usage with no benefit to either the site or to ATLAS. Another impact is the number of empty pilots being processed by a site's Compute Element and batch system which can be 5% of the total number of pilots being handled. In this paper we review the latest statistics using both ATLAS and site data and highlight edge cases where the number of empty pilots dominate. We also study the effect of tuning the pilot factories to reduce the number of empty pilots.

  15. Simulation and Analysis of Wind Turbine Wakes

    DEFF Research Database (Denmark)

    Sørensen, Jens Nørkær

    2017-01-01

    Modern wind turbines are often clustered in wind farms in which the turbines are fully or partially influenced by the wake of upstream located turbines. As a consequence, the wake behind the wind turbines has a lower mean wind speed and an increased turbulence level, as compared to the undisturbed...... flow outside the farm. Hence, wake interaction leads to a decreased total production of power, caused by lower kinetic energy in the wind, and an increase in the turbulence intensity. The turbulence created from wind turbine wakes is mainly due to the presence of the distinct tip and root vortices......, which eventually break down and forms small-scale turbulent structures. If a wind turbine is located in a wake consisting of tip and root vortices, the fatigue loading is more severe than in the case where the tip vortices have already broken down by instability mechanisms. Therefore, understanding...

  16. Failure Modes and Effects Analysis (FMEA) for wind turbines.

    OpenAIRE

    Arabian-Hoseynabadi, H.; Oraee, H.; Tavner, P.J.

    2010-01-01

    The Failure Modes and Effects Analysis (FMEA) method has been used to study the reliability of many different power generation systems. This paper now applies that method to a wind turbine (WT) system using a proprietary software reliability analysis tool. Comparison is made between the quantitative results of an FMEA and reliability field data from real wind turbine systems and their assemblies. These results are discussed to establish relationships which are useful for future wind turbine d...

  17. Technical analysis of photovoltaic/wind systems with hydrogen storage

    OpenAIRE

    Bakić Vukman V.; Pezo Milada L.; Jovanović Marina P.; Turanjanin Valentina M.; Vučićević Biljana S.

    2012-01-01

    The technical analysis of a hybrid wind-photovoltaic energy system with hydrogen gas storage was studied. The market for the distributed power generation based on renewable energy is increasing, particularly for the standalone mini-grid applications. The main design components of PV/Wind hybrid system are the PV panels, the wind turbine and an alkaline electrolyzer with tank. The technical analysis is based on the transient system simulation program TRNSYS 16. The study is realized usin...

  18. Cluster Analysis of the Wind Events and Seasonal Wind Circulation Patterns in the Mexico City Region

    Directory of Open Access Journals (Sweden)

    Susana Carreón-Sierra

    2015-07-01

    Full Text Available The residents of Mexico City face serious problems of air pollution. Identifying the most representative scenarios for the transport and dispersion of air pollutants requires the knowledge of the main wind circulation patterns. In this paper, a simple method to recognize and characterize the wind circulation patterns in a given region is proposed and applied to the Mexico City winds (2001–2006. This method uses a lattice wind approach to model the local wind events at the meso-β scale, and hierarchical cluster analysis to recognize their agglomerations in their phase space. Data of the meteorological network of Mexico City was used as input for the lattice wind model. The Ward’s clustering algorithm with Euclidean distance was applied to organize the model wind events in seasonal clusters for each year of the period. Comparison of the hourly population trends of these clusters permitted the recognition and detailed description of seven circulation patterns. These patterns resemble the qualitative descriptions of the Mexico City wind circulation modes reported by other authors. Our method, however, permitted also their quantitative characterization in terms of the wind attributes of velocity, divergence and vorticity, and an estimation of their seasonal and annual occurrence probabilities, which never before were quantified.

  19. Atlas-Guided Cluster Analysis of Large Tractography Datasets

    Science.gov (United States)

    Ros, Christian; Güllmar, Daniel; Stenzel, Martin; Mentzel, Hans-Joachim; Reichenbach, Jürgen Rainer

    2013-01-01

    Diffusion Tensor Imaging (DTI) and fiber tractography are important tools to map the cerebral white matter microstructure in vivo and to model the underlying axonal pathways in the brain with three-dimensional fiber tracts. As the fast and consistent extraction of anatomically correct fiber bundles for multiple datasets is still challenging, we present a novel atlas-guided clustering framework for exploratory data analysis of large tractography datasets. The framework uses an hierarchical cluster analysis approach that exploits the inherent redundancy in large datasets to time-efficiently group fiber tracts. Structural information of a white matter atlas can be incorporated into the clustering to achieve an anatomically correct and reproducible grouping of fiber tracts. This approach facilitates not only the identification of the bundles corresponding to the classes of the atlas; it also enables the extraction of bundles that are not present in the atlas. The new technique was applied to cluster datasets of 46 healthy subjects. Prospects of automatic and anatomically correct as well as reproducible clustering are explored. Reconstructed clusters were well separated and showed good correspondence to anatomical bundles. Using the atlas-guided cluster approach, we observed consistent results across subjects with high reproducibility. In order to investigate the outlier elimination performance of the clustering algorithm, scenarios with varying amounts of noise were simulated and clustered with three different outlier elimination strategies. By exploiting the multithreading capabilities of modern multiprocessor systems in combination with novel algorithms, our toolkit clusters large datasets in a couple of minutes. Experiments were conducted to investigate the achievable speedup and to demonstrate the high performance of the clustering framework in a multiprocessing environment. PMID:24386292

  20. Job optimization in ATLAS TAG-based distributed analysis

    Science.gov (United States)

    Mambelli, M.; Cranshaw, J.; Gardner, R.; Maeno, T.; Malon, D.; Novak, M.

    2010-04-01

    The ATLAS experiment is projected to collect over one billion events/year during the first few years of operation. The efficient selection of events for various physics analyses across all appropriate samples presents a significant technical challenge. ATLAS computing infrastructure leverages the Grid to tackle the analysis across large samples by organizing data into a hierarchical structure and exploiting distributed computing to churn through the computations. This includes events at different stages of processing: RAW, ESD (Event Summary Data), AOD (Analysis Object Data), DPD (Derived Physics Data). Event Level Metadata Tags (TAGs) contain information about each event stored using multiple technologies accessible by POOL and various web services. This allows users to apply selection cuts on quantities of interest across the entire sample to compile a subset of events that are appropriate for their analysis. This paper describes new methods for organizing jobs using the TAGs criteria to analyze ATLAS data. It further compares different access patterns to the event data and explores ways to partition the workload for event selection and analysis. Here analysis is defined as a broader set of event processing tasks including event selection and reduction operations ("skimming", "slimming" and "thinning") as well as DPD making. Specifically it compares analysis with direct access to the events (AOD and ESD data) to access mediated by different TAG-based event selections. We then compare different ways of splitting the processing to maximize performance.

  1. Job optimization in ATLAS TAG-based distributed analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mambelli, M; Gardner, R [University of Chicago, 5640 S Ellis, Chicago, IL 60637 (United States); Cranshaw, J; Malon, D [Argonne National Laboratory, Argonne, IL 60439 (United States); Maeno, T; Novak, M, E-mail: marco@hep.uchicago.ed [Brookhaven National Laboratory, Brookhaven, NY 10000 (United States)

    2010-04-01

    The ATLAS experiment is projected to collect over one billion events/year during the first few years of operation. The efficient selection of events for various physics analyses across all appropriate samples presents a significant technical challenge. ATLAS computing infrastructure leverages the Grid to tackle the analysis across large samples by organizing data into a hierarchical structure and exploiting distributed computing to churn through the computations. This includes events at different stages of processing: RAW, ESD (Event Summary Data), AOD (Analysis Object Data), DPD (Derived Physics Data). Event Level Metadata Tags (TAGs) contain information about each event stored using multiple technologies accessible by POOL and various web services. This allows users to apply selection cuts on quantities of interest across the entire sample to compile a subset of events that are appropriate for their analysis. This paper describes new methods for organizing jobs using the TAGs criteria to analyze ATLAS data. It further compares different access patterns to the event data and explores ways to partition the workload for event selection and analysis. Here analysis is defined as a broader set of event processing tasks including event selection and reduction operations ('skimming', 'slimming' and 'thinning') as well as DPD making. Specifically it compares analysis with direct access to the events (AOD and ESD data) to access mediated by different TAG-based event selections. We then compare different ways of splitting the processing to maximize performance.

  2. Statistical Modelling of Wind Proles - Data Analysis and Modelling

    DEFF Research Database (Denmark)

    Jónsson, Tryggvi; Pinson, Pierre

    The aim of the analysis presented in this document is to investigate whether statistical models can be used to make very short-term predictions of wind profiles.......The aim of the analysis presented in this document is to investigate whether statistical models can be used to make very short-term predictions of wind profiles....

  3. Thermal analysis of the airflow around ATLAS muon end cap

    CERN Document Server

    Gasser, D

    2003-01-01

    A thermal analysis of the airflow inside the UX15 cavern and through the ATLAS detector is presented. This study is done using a CFD (Computational Fluid Dynamics) model. This model includes a simplified geometry of the detector and the experimental cavern, the ventilation flow rate and the released heat dissipation figures are taken into account. This analysis aims at estimate the temperature gradients that develop in the muons end cap area. Indeed, light rays seen by CCD camera will be used in this area in order to align the muon chambers. The rays should not be too much distorted by temperature difference, which would hinder the chamber alignment. The simulation results show that a light ray projected through the whole end cap area should not encounter a gradient higher than 5 K. Nevertheless, the results of this analysis are valid if and only if the spaces represented as empty in the model are allowed to remain empty in ATLAS.

  4. Wind energy potential analysis in Al-Fattaih-Darnah

    Energy Technology Data Exchange (ETDEWEB)

    Tjahjana, Dominicus Danardono Dwi Prija, E-mail: danar1405@gmail.com; Salem, Abdelkarim Ali, E-mail: keemsalem@gmail.com; Himawanto, Dwi Aries, E-mail: dwiarieshimawanto@gmail.com [University of Sebelas Maret, Jl. Ir. Sutami No. 36 A, Surakarta, Indonesia 57126 (Indonesia)

    2016-03-29

    In this paper the wind energy potential in Al-Fattaih-Darnah, Libya, had been studied. Wind energy is very attractive because it can provide a clean and renewable energy. Due mostly to the uncertainty caused by the chaotic characteristics of wind near the earth’s surface, wind energy characteristic need to be investigated carefully in order to get consistent power generation. This investigation was based on one year wind data measured in 2003. As a result of the analysis, wind speed profile and wind energy potential have been developed. The wind energy potential of the location is looked very promising to generate electricity. The annual wind speed of the site is 8.21 m/s and the wind speed carrying maximum energy is 7.97 m/s. The annual power density of the site is classified into class 3. The Polaris P50-500 wind turbine can produce 768.39 M Wh/year and has capacity factor of 17.54%.

  5. Hourly wind speed analysis in Sicily

    Energy Technology Data Exchange (ETDEWEB)

    Bivona, S.; Leone, C. [Palermo Univ., Dip di Fisica e Technologie Relative, Palermo (Italy); Burlon, R. [Palermo Univ., Dip. di Ingegnaria Nucleare, Palermo (Italy)

    2003-07-01

    The hourly average wind speed data recorded by CNMCA (Centro Nazionale di Meteorologia e Climatologia Aeronautica) have been used to study the statistical properties of the wind speed at nine locations on Sicily. By grouping the observations month by month, we show that the hourly average wind speed, with calms omitted, is represented by a Weibull function. The suitability of the distribution is judged by the discrepancies between the observed and calculated values of the monthly average wind speed and of the standard deviation. (Author)

  6. Comparative analysis of wind energy production in Oklahoma

    Science.gov (United States)

    Ermilova, Ekaterina Alexeevna

    Scope and method of study. In the last decades humanity has realized the necessity of developing alternative energy sources for its efficient economic development and simple survival in the future. During the last 30 years major improvements were made in renewable energy technologies and they started to become competitive with traditional energy sources (fossil fuels), especially with consideration of external costs. Among the renewable energy sources, wind energy is one of the cheapest and fastest growing nowadays. Oklahoma is a very promising site for wind energy development considering its excellent wind resources. Developing wind energy can allow not only electricity production for in-state consumption, but also exporting to other states. The development of wind energy could encourage economic growth with very few adverse impacts on the environment. However, traditional energy sources are still the cheapest and, thus, the introduction of the wind energy in Oklahoma should be critically analyzed from economic, ecological and social points of view. The goal of this study is to conduct analysis of wind energy electricity production in Oklahoma on the four main stages: (1) Investment Analysis from Private Perspective: Calculate present value net benefits for wind energy and traditional energy (natural gas), make sure that both of them are positive. (2) Investment Analysis from Social Perspective: Evaluate present value net private benefits (PVNPB) and present value net social benefit from both projects (PVNSB). (3) Government Subsidy Analysis: recognize the necessity of the subsidies and evaluate the amount of subsidies if any. (4) Investment Analysis from a Geographic Perspective: determine economic feasibility of wind power generation for 77 Oklahoma counties. Findings and conclusions. The final output of the study is the recommendations concerning wind energy development in Oklahoma with consideration of economic efficiency, ecological and social impacts. Study

  7. The UTRC wind energy conversion system performance analysis for horizontal axis wind turbines (WECSPER)

    Science.gov (United States)

    Egolf, T. A.; Landgrebe, A. J.

    1981-01-01

    The theory for the UTRC Energy Conversion System Performance Analysis (WECSPER) for the prediction of horizontal axis wind turbine performance is presented. Major features of the analysis are the ability to: (1) treat the wind turbine blades as lifting lines with a prescribed wake model; (2) solve for the wake-induced inflow and blade circulation using real nonlinear airfoil data; and (3) iterate internally to obtain a compatible wake transport velocity and blade loading solution. This analysis also provides an approximate treatment of wake distortions due to tower shadow or wind shear profiles. Finally, selected results of internal UTRC application of the analysis to existing wind turbines and correlation with limited test data are described.

  8. Lake Michigan Wind Assessment Analysis, 2012 and 2013

    Directory of Open Access Journals (Sweden)

    Charles R Standridge

    2017-03-01

    Full Text Available A study was conducted to address the wind energy potential over Lake Michigan to support a commercial wind farm.  Lake Michigan is an inland sea in the upper mid-western United States.  A laser wind sensor mounted on a floating platform was located at the mid-lake plateau in 2012 and about 10.5 kilometers from the eastern shoreline near Muskegon Michigan in 2013.  Range gate heights for the laser wind sensor were centered at 75, 90, 105, 125, 150, and 175 meters.  Wind speed and direction were measured once each second and aggregated into 10 minute averages.  The two sample t-test and the paired-t method were used to perform the analysis.  Average wind speed stopped increasing between 105 m and 150 m depending on location.  Thus, the collected data is inconsistent with the idea that average wind speed increases with height. This result implies that measuring wind speed at wind turbine hub height is essential as opposed to using the wind energy power law to project the wind speed from lower heights.  Average speed at the mid-lake plateau is no more that 10% greater than at the location near Muskegon.  Thus, it may be possible to harvest much of the available wind energy at a lower height and closer to the shoreline than previously thought.  At both locations, the predominate wind direction is from the south-southwest.  The ability of the laser wind sensor to measure wind speed appears to be affected by a lack of particulate matter at greater heights.   Keywords: wind assessment, Lake Michigan, LIDAR wind sensor, statistical analysis. Article History: Received June 15th 2016; Received in revised form January 16th 2017; Accepted February 2nd 2017 Available online How to Cite This Article: Standridge, C., Zeitler, D., Clark, A., Spoelma, T., Nordman, E., Boezaart, T.A., Edmonson, J.,  Howe, G., Meadows, G., Cotel, A. and Marsik, F. (2017 Lake Michigan Wind Assessment Analysis, 2012 and 2013. Int. Journal of Renewable Energy Development

  9. Integrated analysis of wind turbines - The impact of power systems on wind turbine design

    DEFF Research Database (Denmark)

    Barahona Garzón, Braulio

    Megawatt-size wind turbines nowadays operate in very complex environmental conditions, and increasingly demanding power system requirements. Pursuing a cost-effective and reliable wind turbine design is a multidisciplinary task. However nowadays, wind turbine design and research areas...... conditions that stem from disturbances in the power system. An integrated simulation environment, wind turbine models, and power system models are developed in order to take an integral perspective that considers the most important aeroelastic, structural, electrical, and control dynamics. Applications...... of the integrated simulation environment are presented. The analysis of an asynchronous machine, and numerical simulations of a fixedspeed wind turbine in the integrated simulation environment, demonstrate the effects on structural loads of including the generator rotor fluxes dynamics in aeroelastic studies. Power...

  10. Detection of Wind Turbine Power Performance Abnormalities Using Eigenvalue Analysis

    Science.gov (United States)

    2014-12-23

    Detection of Wind Turbine Power Performance Abnormalities Using Eigenvalue Analysis Georgios Alexandros Skrimpas1, Christian Walsted Sweeney2, Kun S...the following equation: P = 0.5ρACp(λ, β)u 3 (1) where P is the power captured by the wind turbine rotor, ρ is the air density, A is the swept rotor...may complicate the identification of abnor- malities. In addition to the above, the wind turbine power production can be affected by external factors

  11. Danish wind power in Brazil. Part 3. Brazilian wind conditions

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, M.E.; Farias, G. [Federal Univ. of Pernambuco, Wind Energy Group (Brazil)

    1996-01-01

    The report is prepared by the Wind Energy Group/Federal University of Pernambuco for the Folkecenter/Denmark. Its principle objective is to give representative wind data measured in several parts of Brazil. Topography analysis and other factors are also included. The Wind Energy Group at the Federal University of Pernambuco works for several state utility companies with the aim of the future production of a precise wind map of several regions in Brazil; Ceara, Para, Pernambuco, Alagoas, Bahia, Minas, Gerais and Parana, and in this report wind data from these areas are presented. The wind maps are analyzed using the `Wind Atlas Analysis and Application Program` (WASP) developed at Risoe National Laboratory, Roskilde, Denmark, and the accuracy of the wind speed measurements are guaranteed by calibration of the cup anemometers. A paper about, and giving data on, trade winds in Brazil is presented in the form of an appendix. Here it is concluded that wind characteristics in the Brazilian state of Ceara are unique and that the winds are very steady indeed, there are no gusts and winds have a low turbulence intensity. The variation of direction is limited to 1/4 of the wind rose. These winds are different from those encountered in Western Europe and North America and this necessitates a new design philosophy for the rotor, yaw mechanism and control system of any wind turbines to be installed in the region. (AB)

  12. Analysis of Mexico wind tunnel measurements

    DEFF Research Database (Denmark)

    Schepers, J.G.; Boorsma, K.; Cho, T.

    institutes carried out a wind tunnel experiment in the Large Low Speed Facility (LLF) of the German DutchWind Facilities DNW on a rotor with a diameter of 4.5 m. Pressure distributions were measured at five location along the blade along with detailed flow field measurements around the rotor plane using...

  13. ATLAS

    CERN Multimedia

    Akhnazarov, V; Canepa, A; Bremer, J; Burckhart, H; Cattai, A; Voss, R; Hervas, L; Kaplon, J; Nessi, M; Werner, P; Ten kate, H; Tyrvainen, H; Vandelli, W; Krasznahorkay, A; Gray, H; Alvarez gonzalez, B; Eifert, T F; Rolando, G; Oide, H; Barak, L; Glatzer, J; Backhaus, M; Schaefer, D M; Maciejewski, J P; Milic, A; Jin, S; Von torne, E; Limbach, C; Medinnis, M J; Gregor, I; Levonian, S; Schmitt, S; Waananen, A; Monnier, E; Muanza, S G; Pralavorio, P; Talby, M; Tiouchichine, E; Tocut, V M; Rybkin, G; Wang, S; Lacour, D; Laforge, B; Ocariz, J H; Bertoli, W; Malaescu, B; Sbarra, C; Yamamoto, A; Sasaki, O; Koriki, T; Hara, K; Da silva gomes, A; Carvalho maneira, J; Marcalo da palma, A; Chekulaev, S; Tikhomirov, V; Snesarev, A; Buzykaev, A; Maslennikov, A; Peleganchuk, S; Sukharev, A; Kaplan, B E; Swiatlowski, M J; Nef, P D; Schnoor, U; Oakham, G F; Ueno, R; Orr, R S; Abouzeid, O; Haug, S; Peng, H; Kus, V; Vitek, M; Temming, K K; Dang, N P; Meier, K; Schultz-coulon, H; Geisler, M P; Sander, H; Schaefer, U; Ellinghaus, F; Rieke, S; Nussbaumer, A; Liu, Y; Richter, R; Kortner, S; Fernandez-bosman, M; Ullan comes, M; Espinal curull, J; Chiriotti alvarez, S; Caubet serrabou, M; Valladolid gallego, E; Kaci, M; Carrasco vela, N; Lancon, E C; Besson, N E; Gautard, V; Bracinik, J; Bartsch, V C; Potter, C J; Lester, C G; Moeller, V A; Rosten, J; Crooks, D; Mathieson, K; Houston, S C; Wright, M; Jones, T W; Harris, O B; Byatt, T J; Dobson, E; Hodgson, P; Hodgkinson, M C; Dris, M; Karakostas, K; Ntekas, K; Oren, D; Duchovni, E; Etzion, E; Oren, Y; Ferrer, L M; Testa, M; Doria, A; Merola, L; Sekhniaidze, G; Giordano, R; Ricciardi, S; Milazzo, A; Falciano, S; De pedis, D; Dionisi, C; Veneziano, S; Cardarelli, R; Verzegnassi, C; Soualah, R; Ochi, A; Ohshima, T; Kishiki, S; Linde, F L; Vreeswijk, M; Werneke, P; Muijs, A; Vankov, P H; Jansweijer, P P M; Dale, O; Lund, E; Bruckman de renstrom, P; Dabrowski, W; Adamek, J D; Wolters, H; Micu, L; Pantea, D; Tudorache, V; Mjoernmark, J; Klimek, P J; Ferrari, A; Abdinov, O; Akhoundov, A; Hashimov, R; Shelkov, G; Khubua, J; Ladygin, E; Lazarev, A; Glagolev, V; Dedovich, D; Lykasov, G; Zhemchugov, A; Zolnikov, Y; Ryabenko, M; Sivoklokov, S; Vasilyev, I; Shalimov, A; Lobanov, M; Paramoshkina, E; Mosidze, M; Bingul, A; Nodulman, L J; Guarino, V J; Yoshida, R; Drake, G R; Calafiura, P; Haber, C; Quarrie, D R; Alonso, J R; Anderson, C; Evans, H; Lammers, S W; Baubock, M; Anderson, K; Petti, R; Suhr, C A; Linnemann, J T; Richards, R A; Tollefson, K A; Holzbauer, J L; Stoker, D P; Pier, S; Nelson, A J; Isakov, V; Martin, A J; Adelman, J A; Paganini, M; Gutierrez, P; Snow, J M; Pearson, B L; Cleland, W E; Savinov, V; Wong, W; Goodson, J J; Li, H; Lacey, R A; Gordeev, A; Gordon, H; Lanni, F; Nevski, P; Rescia, S; Kierstead, J A; Liu, Z; Yu, W W H; Bensinger, J; Hashemi, K S; Bogavac, D; Cindro, V; Hoeferkamp, M R; Coelli, S; Iodice, M; Piegaia, R N; Alonso, F; Wahlberg, H P; Barberio, E L; Limosani, A; Rodd, N L; Jennens, D T; Hill, E C; Pospisil, S; Smolek, K; Schaile, D A; Rauscher, F G; Adomeit, S; Mattig, P M; Wahlen, H; Volkmer, F; Calvente lopez, S; Sanchis peris, E J; Pallin, D; Podlyski, F; Says, L; Boumediene, D E; Scott, W; Phillips, P W; Greenall, A; Turner, P; Gwilliam, C B; Kluge, T; Wrona, B; Sellers, G J; Millward, G; Adragna, P; Hartin, A; Alpigiani, C; Piccaro, E; Bret cano, M; Hughes jones, R E; Mercer, D; Oh, A; Chavda, V S; Carminati, L; Cavasinni, V; Fedin, O; Patrichev, S; Ryabov, Y; Nesterov, S; Grebenyuk, O; Sasso, J; Mahmood, H; Polsdofer, E; Dai, T; Ferretti, C; Liu, H; Hegazy, K H; Benjamin, D P; Zobernig, G; Ban, J; Brooijmans, G H; Keener, P; Williams, H H; Le geyt, B C; Hines, E J; Fadeyev, V; Schumm, B A; Law, A T; Kuhl, A D; Neubauer, M S; Shang, R; Gagliardi, G; Calabro, D; Conta, C; Zinna, M; Jones, G; Li, J; Stradling, A R; Hadavand, H K; Mcguigan, P; Chiu, P; Baldelomar, E; Stroynowski, R A; Kehoe, R L; De groot, N; Timmermans, C; Lach-heb, F; Addy, T N; Nakano, I; Moreno lopez, D; Grosse-knetter, J; Tyson, B; Rude, G D; Tafirout, R; Benoit, P; Danielsson, H O; Elsing, M; Fassnacht, P; Froidevaux, D; Ganis, G; Gorini, B; Lasseur, C; Lehmann miotto, G; Kollar, D; Aleksa, M; Sfyrla, A; Duehrssen-debling, K; Fressard-batraneanu, S; Van der ster, D C; Bortolin, C; Schumacher, J; Mentink, M; Geich-gimbel, C; Yau wong, K H; Lafaye, R; Crepe-renaudin, S; Albrand, S; Hoffmann, D; Pangaud, P; Meessen, C; Hrivnac, J; Vernay, E; Perus, A; Henrot versille, S L; Le dortz, O; Derue, F; Piccinini, M; Polini, A; Terada, S; Arai, Y; Ikeno, M; Fujii, H; Nagano, K; Ukegawa, F; Aguilar saavedra, J A; Conde muino, P; Castro, N F; Eremin, V; Kopytine, M; Sulin, V; Tsukerman, I; Korol, A; Nemethy, P; Bartoldus, R; Glatte, A; Chelsky, S; Van nieuwkoop, J; Bellerive, A; Sinervo, J K; Battaglia, A; Barbier, G J; Pohl, M; Rosselet, L; Alexandre, G B; Prokoshin, F; Pezoa rivera, R A; Batkova, L; Kladiva, E; Stastny, J; Kubes, T; Vidlakova, Z; Esch, H; Homann, M; Herten, L G; Zimmermann, S U; Pfeifer, B; Stenzel, H; Andrei, G V; Wessels, M; Buescher, V; Kleinknecht, K; Fiedler, F M; Schroeder, C D; Fernandez, E; Mir martinez, L; Vorwerk, V; Bernabeu verdu, J; Salt, J; Civera navarrete, J V; Bernard, R; Berriaud, C P; Chevalier, L P; Hubbard, R; Schune, P; Nikolopoulos, K; Batley, J R; Brochu, F M; Phillips, A W; Teixeira-dias, P J; Rose, M B D; Buttar, C; Buckley, A G; Nurse, E L; Larner, A B; Boddy, C; Henderson, J; Costanzo, D; Tarem, S; Maccarrone, G; Laurelli, P F; Alviggi, M; Chiaramonte, R; Izzo, V; Palumbo, V; Fraternali, M; Crosetti, G; Marchese, F; Yamaguchi, Y; Hessey, N P; Mechnich, J M; Liebig, W; Kastanas, K A; Sjursen, T B; Zalieckas, J; Cameron, D G; Banka, P; Kowalewska, A B; Dwuznik, M; Mindur, B; Boldea, V; Hedberg, V; Smirnova, O; Sellden, B; Allahverdiyev, T; Gornushkin, Y; Koultchitski, I; Tokmenin, V; Chizhov, M; Gongadze, A; Khramov, E; Sadykov, R; Krasnoslobodtsev, I; Smirnova, L; Kramarenko, V; Minaenko, A; Zenin, O; Beddall, A J; Ozcan, E V; Hou, S; Wang, S; Moyse, E; Willocq, S; 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Wickens, F J; Martin, V J; Jackson, J N; Prichard, P; Kretzschmar, J; Martin, A J; Walker, C J; Potter, K M; Kourkoumelis, C; Tzamarias, S; Houiris, A G; Iliadis, D; Fanti, M; Bertolucci, F; Maleev, V; Sultanov, S; Rosenberg, E I; Krumnack, N E; Bieganek, C; Diehl, E B; Mc kee, S P; Eppig, A P; Harper, D R; Liu, C; Schwarz, T A; Mazor, B; Looper, K A; Wiedenmann, W; Huang, P; Stahlman, J M; Battaglia, M; Nielsen, J A; Zhao, T; Khanov, A; Kaushik, V S; Vichou, E; Liss, A M; Gemme, C; Morettini, P; Parodi, F; Passaggio, S; Rossi, L; Kuzhir, P; Ignatenko, A; Ferrari, R; Spairani, M; Pianori, E; Sekula, S J; Firan, A I; Cao, T; Hetherly, J W; Gouighri, M; Vassilakopoulos, V; Long, M C; Shimojima, M; Sawyer, L H; Brummett, R E; Losada, M A; Schorlemmer, A L; Mantoani, M; Bawa, H S; Mornacchi, G; Nicquevert, B; Palestini, S; Stapnes, S; Veness, R; Kotamaki, M J; Sorde, C; Iengo, P; Campana, S; Goossens, L; Zajacova, Z; Pribyl, L; Poveda torres, J; Marzin, A; Conti, G; Carrillo montoya, G D; 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Mcgarvie, S A; Kilvington, G J; D'auria, S; O'shea, V; Mcglone, H M; Fox, H; Henderson, R; Kartvelishvili, V; Davies, B; Sherwood, P; Fraser, J T; Lancaster, M A; Tseng, J C; Hays, C P; Apolle, R; Dixon, S D; Parker, K A; Gazis, E; Papadopoulou, T; Panagiotopoulou, E; Karastathis, N; Hershenhorn, A D; Milov, A; Groth-jensen, J; Bilokon, H; Miscetti, S; Canale, V; Rebuzzi, D M; Capua, M; Bagnaia, P; De salvo, A; Gentile, S; Safai tehrani, F; Solfaroli camillocci, E; Sasao, N; Tsunada, K; Massaro, G; Magrath, C A; Van kesteren, Z; Beker, M G; Van den wollenberg, W; Bugge, L; Buran, T; Read, A L; Gjelsten, B K; Banas, E A; Turnau, J; Derendarz, D K; Kisielewska, D; Chesneanu, D; Rotaru, M; Maurer, J B; Wong, M L; Lund-jensen, B; Asman, B; Jon-and, K B; Silverstein, S B; Johansen, M; Alexandrov, I; Iatsounenko, I; Krumshteyn, Z; Peshekhonov, V; Rybaltchenko, K; Samoylov, V; Cheplakov, A; Kekelidze, G; Lyablin, M; Teterine, V; Bednyakov, V; Kruchonak, U; Shiyakova, M M; Demichev, M; Denisov, S P; Fenyuk, A; Djobava, T; Salukvadze, G; Cetin, S A; Brau, B P; Pais, P R; Proudfoot, J; Van gemmeren, P; Zhang, Q; Beringer, J A; Ely, R; Leggett, C; Pengg, F X; Barnett, M R; Quick, R E; Williams, S; Gardner jr, R W; Huston, J; Brock, R; Wanotayaroj, C; Unel, G N; Taffard, A C; Frate, M; Baker, K O; Tipton, P L; Hutchison, A; Walsh, B J; Norberg, S R; Su, J; Tsybyshev, D; Caballero bejar, J; Ernst, M U; Wellenstein, H; Vudragovic, D; Vidic, I; Gorelov, I V; Toms, K; Alimonti, G; Petrucci, F; Kolanoski, H; Smith, J; Jeng, G; Watson, I J; Guimaraes ferreira, F; Miranda vieira xavier, F; Araujo pereira, R; Poffenberger, P; Sopko, V; Elmsheuser, J; Wittkowski, J; Glitza, K; Gorfine, G W; Ferrer soria, A; Fuster verdu, J A; Sanchis lozano, A; Reinmuth, G; Busato, E; Haywood, S J; Mcmahon, S J; Qian, W; Villani, E G; Laycock, P J; Poll, A J; Rizvi, E S; Foster, J M; Loebinger, F; Forti, A; Plano, W G; Brown, G J A; Kordas, K; Vegni, G; Ohsugi, T; Iwata, Y; Cherkaoui el moursli, R; Sahin, M; Akyazi, E; Carlsen, A; Kanwal, B; Cochran jr, J H; Aronnax, M V; Lockner, M J; Zhou, B; Levin, D S; Weaverdyck, C J; Grom, G F; Rudge, A; Ebenstein, W L; Jia, B; Yamaoka, J; Jared, R C; Wu, S L; Banerjee, S; Lu, Q; Hughes, E W; Alkire, S P; Degenhardt, J D; Lipeles, E D; Spencer, E N; Savine, A; Cheu, E C; Lampl, W; Veatch, J R; Roberts, K; Atkinson, M J; Odino, G A; Polesello, G; Martin, T; White, A P; Stephens, R; Grinbaum sarkisyan, E; Vartapetian, A; Yu, J; Sosebee, M; Thilagar, P A; Spurlock, B; Bonde, R; Filthaut, F; Klok, P; Hoummada, A; Ouchrif, M; Pellegrini, G; Rafi tatjer, J M; Navarro, G A; Blumenschein, U; Weingarten, J C; Mueller, D; Graber, L; Gao, Y; Bode, A; Capeans garrido, M D M; Carli, T; Wells, P; Beltramello, O; Vuillermet, R; Dudarev, A; Salzburger, A; Torchiani, C I; Serfon, C L G; Sloper, J E; Duperrier, G; Lilova, P T; Knecht, M O; Lassnig, M; Anders, G; Deviveiros, P; Young, C; Sforza, F; Shaochen, C; Lu, F; Wermes, N; Wienemann, P; Schwindt, T; Hansen, P H; Hansen, J B; Pingel, A M; Massol, N; Elles, S L; Hallewell, G D; Rozanov, A; Vacavant, L; Fournier, D A; Poggioli, L; Puzo, P M; Tanaka, R; Escalier, M A; Makovec, N; Rezynkina, K; De cecco, S; Cavalleri, P G; Massa, I; Zoccoli, A; Tanaka, S; Odaka, S; Mitsui, S; Tomasio pina, J A; Santos, H F; Satsounkevitch, I; Harkusha, S; Baranov, S; Nechaeva, P; Kayumov, F; Kazanin, V; Asai, M; Mount, R P; Nelson, T K; Smith, D; Kenney, C J; Malone, C M; Kobel, M; Friedrich, F; Grohs, J P; Jais, W J; O'neil, D C; Warburton, A T; Vincter, M; Mccarthy, T G; Groer, L S; Pham, Q T; Taylor, W J; La marra, D; Perrin, E; Wu, X; Bell, W H; Delitzsch, C M; Feng, C; Zhu, C; Tokar, S; Bruncko, D; Kupco, A; Marcisovsky, M; Jakoubek, T; Bruneliere, R; Aktas, A; Narrias villar, D I; Tapprogge, S; Mattmann, J; Kroha, H; Crespo, J; Korolkov, I; Cavallaro, E; Cabrera urban, S; Mitsou, V; Kozanecki, W; Mansoulie, B; Pabot, Y; Etienvre, A; Bauer, F; Chevallier, F; Bouty, A R; Watkins, P; Watson, A; Faulkner, P J W; Curtis, C J; Murillo quijada, J A; Grout, Z J; Chapman, J D; Cowan, G D; George, S; Boisvert, V; Mcmahon, T R; Doyle, A T; Thompson, S A; Britton, D; Smizanska, M; Campanelli, M; Butterworth, J M; Loken, J; Renton, P; Barr, A J; Issever, C; Short, D; Crispin ortuzar, M; Tovey, D R; French, R; Rozen, Y; Alexander, G; Kreisel, A; Conventi, F; Raulo, A; Schioppa, M; Susinno, G; Tassi, E; Giagu, S; Luci, C; Nisati, A; Cobal, M; Ishikawa, A; Jinnouchi, O; Bos, K; Verkerke, W; Vermeulen, J; Van vulpen, I B; Kieft, G; Mora, K D; Olsen, F; Rohne, O M; Pajchel, K; Nilsen, J K; Wosiek, B K; Wozniak, K W; Badescu, E; Jinaru, A; Bohm, C; Johansson, E K; Sjoelin, J B R; Clement, C; Buszello, C P; Huseynova, D; Boyko, I; Popov, B; Poukhov, O; Vinogradov, V; Tsiareshka, P; Skvorodnev, N; Soldatov, A; Chuguev, A; Gushchin, V; Yazici, E; Lutz, M S; Malon, D; Vanyashin, A; Lavrijsen, W; Spieler, H; Biesiada, J L; Bahr, M; Kong, J; Tatarkhanov, M; Ogren, H; Van kooten, R J; Cwetanski, P; Butler, J M; Shank, J T; Chakraborty, D; Ermoline, I; Sinev, N; Whiteson, D O; Corso radu, A; Huang, J; Werth, M P; Kastoryano, M; Meirose da silva costa, B; Namasivayam, H; Hobbs, J D; Schamberger jr, R D; Guo, F; Potekhin, M; Popovic, D; Gorisek, A; Sokhrannyi, G; Hofsajer, I W; Mandelli, L; Ceradini, F; Graziani, E; Giorgi, F; Zur nedden, M E G; Grancagnolo, S; Volpi, M; Nunes hanninger, G; Rados, P K; Milesi, M; Cuthbert, C J; Black, C W; Fink grael, F; Fincke-keeler, M; Keeler, R; Kowalewski, R V; Berghaus, F O; Qi, M; Davidek, T; Tas, P; Jakubek, J; Duckeck, G; Walker, R; Mitterer, C A; Harenberg, T; Sandvoss, S A; Del peso, J; Llorente merino, J; Gonzalez millan, V; Irles quiles, A; Crouau, M; Gris, P L Y; Liauzu, S; Romano saez, S M; Gallop, B J; Jones, T J; Austin, N C; Morris, J; Duerdoth, I; Thompson, R J; Kelly, M P; Leisos, A; Garas, A; Pizio, C; Venda pinto, B A; Kudin, L; Qian, J; Wilson, A W; Mietlicki, D; Long, J D; Sang, Z; Arms, K E; Rahimi, A M; Moss, J J; Oh, S H; Parker, S I; Parsons, J; Cunitz, H; Vanguri, R S; Sadrozinski, H; Lockman, W S; Martinez-mc kinney, G; Goussiou, A; Jones, A; Lie, K; Hasegawa, Y; Olcese, M; Gilewsky, V; Harrison, P F; Janus, M; Spangenberg, M; De, K; Ozturk, N; Pal, A K; Darmora, S; Bullock, D J; Oviawe, O; Derkaoui, J E; Rahal, G; Sircar, A; Frey, A S; Stolte, P; Rosien, N; Zoch, K; Li, L; Schouten, D W; Catinaccio, A; Ciapetti, M; Delruelle, N; Ellis, N; Farthouat, P; Hoecker, A; Klioutchnikova, T; Macina, D; Malyukov, S; Spiwoks, R D; Unal, G P; Vandoni, G; Petersen, B A; Pommes, K; Nairz, A M; Wengler, T; Mladenov, D; Solans sanchez, C A; Lantzsch, K; Schmieden, K; Jakobsen, S; Ritsch, E; Sciuccati, A; Alves dos santos, A M; Ouyang, Q; Zhou, M; Brock, I C; Janssen, J; Katzy, J; Anders, C F; Nilsson, B S; Bazan, A; Di ciaccio, L; Yildizkaya, T; Collot, J; Malek, F; Trocme, B S; Breugnon, P; Godiot, S; Adam bourdarios, C; Coulon, J; Duflot, L; Petroff, P G; Zerwas, D; Lieuvin, M; Calderini, G; Laporte, D; Ocariz, J; Gabrielli, A; Ohska, T K; Kurochkin, Y; Kantserov, V; Vasilyeva, L; Speransky, M; Smirnov, S; Antonov, A; Bulekov, O; Tikhonov, Y; Sargsyan, L; Vardanyan, G; Budick, B; Kocian, M L; Luitz, S; Young, C C; Grenier, P J; Kelsey, M; Black, J E; Kneringer, E; Jussel, P; Horton, A J; Beaudry, J; Chandra, A; Ereditato, A; Topfel, C M; Mathieu, R; Bucci, F; Muenstermann, D; White, R M; He, M; Urban, J; Straka, M; Vrba, V; Schumacher, M; Parzefall, U; Mahboubi, K; Sommer, P O; Koepke, L H; Bethke, S; Moser, H; Wiesmann, M; Walkowiak, W A; Fleck, I J; Martinez-perez, M; Sanchez sanchez, C A; Jorgensen roca, S; Accion garcia, E; Sainz ruiz, C A; Valls ferrer, J A; Amoros vicente, G; Vives torrescasana, R; Ouraou, A; Formica, A; Hassani, S; Watson, M F; Cottin buracchio, G F; Bussey, P J; Saxon, D; Ferrando, J E; Collins-tooth, C L; Hall, D C; Cuhadar donszelmann, T; Dawson, I; Duxfield, R; Argyropoulos, T; Brodet, E; Livneh, R; Shougaev, K; Reinherz, E I; Guttman, N; Beretta, M M; Vilucchi, E; Aloisio, A; Patricelli, S; Caprio, M; Cevenini, F; De vecchi, C; Livan, M; Rimoldi, A; Vercesi, V; Ayad, R; Mastroberardino, A; Ciapetti, G; Luminari, L; Rescigno, M; Santonico, R; Salamon, A; Del papa, C; Kurashige, H; Homma, Y; Tomoto, M; Horii, Y; Sugaya, Y; Hanagaki, K; Bobbink, G; Kluit, P M; Koffeman, E N; Van eijk, B; Lee, H; Eigen, G; Dorholt, O; Strandlie, A; Strzempek, P B; Dita, S; Stoicea, G; Chitan, A; Leven, S S; Moa, T; Brenner, R; Ekelof, T J C; Olshevskiy, A; Roumiantsev, V; Chlachidze, G; Zimine, N; Gusakov, Y; Grigalashvili, N; Mineev, M; Potrap, I; Barashkou, A; Shoukavy, D; Shaykhatdenov, B; Pikelner, A; Gladilin, L; Ammosov, V; Abramov, A; Arik, M; Sahinsoy, M; Uysal, Z; Azizi, K; Hotinli, S C; Zhou, S; Berger, E; Blair, R; Underwood, D G; Einsweiler, K; Garcia-sciveres, M A; Siegrist, J L; Kipnis, I; Dahl, O; Holland, S; Barbaro galtieri, A; Smith, P T; Parua, N; Franklin, M; Mercurio, K M; Tong, B; Pod, E; Cole, S G; Hopkins, W H; Guest, D H; Severini, H; Marsicano, J J; Abbott, B K; Wang, Q; Lissauer, D; Ma, H; Takai, H; Rajagopalan, S; Protopopescu, S D; Snyder, S S; Undrus, A; Popescu, R N; Begel, M A; Blocker, C A; Amelung, C; Mandic, I; Macek, B; Tucker, B H; Citterio, M; Troncon, C; Orestano, D; Taccini, C; Romeo, G L; Dova, M T; Taylor, G N; Gesualdi manhaes, A; Mcpherson, R A; Sobie, R; Taylor, R P; Dolezal, Z; Kodys, P; Slovak, R; Sopko, B; Vacek, V; Sanders, M P; Hertenberger, R; Meineck, C; Becks, K; Kind, P; Sandhoff, M; Cantero garcia, J; De la torre perez, H; Castillo gimenez, V; Ros, E; Hernandez jimenez, Y; Chadelas, R; Santoni, C; Washbrook, A J; O'brien, B J; Wynne, B M; Mehta, A; Vossebeld, J H; Landon, M; Teixeira dias castanheira, M; Cerrito, L; Keates, J R; Fassouliotis, D; Chardalas, M; Manousos, A; Grachev, V; Seliverstov, D; Sedykh, E; Cakir, O; Ciftci, R; Edson, W; Prell, S A; Rosati, M; Stroman, T; Jiang, H; Neal, H A; Li, X; Gan, K K; Smith, D S; Kruse, M C; Ko, B R; Leung fook cheong, A M; Cole, B; Angerami, A R; Greene, Z S; Kroll, J I; Van berg, R P; Forbush, D A; Lubatti, H; Raisher, J; Shupe, M A; Wolin, S; Oshita, H; Gaudio, G; Das, R; Konig, A C; Croft, V A; Harvey, A; Maaroufi, F; Melo, I; Greenwood jr, Z D; Shabalina, E; Mchedlidze, G; Drechsler, E; Rieger, J K; Blackston, M; Colombo, T

    2002-01-01

    % ATLAS \\\\ \\\\ ATLAS is a general-purpose experiment for recording proton-proton collisions at LHC. The ATLAS collaboration consists of 144 participating institutions (June 1998) with more than 1750~physicists and engineers (700 from non-Member States). The detector design has been optimized to cover the largest possible range of LHC physics: searches for Higgs bosons and alternative schemes for the spontaneous symmetry-breaking mechanism; searches for supersymmetric particles, new gauge bosons, leptoquarks, and quark and lepton compositeness indicating extensions to the Standard Model and new physics beyond it; studies of the origin of CP violation via high-precision measurements of CP-violating B-decays; high-precision measurements of the third quark family such as the top-quark mass and decay properties, rare decays of B-hadrons, spectroscopy of rare B-hadrons, and $ B ^0 _{s} $-mixing. \\\\ \\\\The ATLAS dectector, shown in the Figure includes an inner tracking detector inside a 2~T~solenoid providing an axial...

  14. Statistical and Spectral Analysis of Wind Characteristics Relevant to Wind Energy Assessment Using Tower Measurements in Complex Terrain

    OpenAIRE

    Radian Belu; Darko Koracin

    2013-01-01

    The main objective of the study was to investigate spatial and temporal characteristics of the wind speed and direction in complex terrain that are relevant to wind energy assessment and development, as well as to wind energy system operation, management, and grid integration. Wind data from five tall meteorological towers located in Western Nevada, USA, operated from August 2003 to March 2008, used in the analysis. The multiannual average wind speeds did not show significant increased trend ...

  15. Reliability Analysis of Fatigue Fracture of Wind Turbine Drivetrain Components

    DEFF Research Database (Denmark)

    Berzonskis, Arvydas; Sørensen, John Dalsgaard

    2016-01-01

    in the volume of the casted ductile iron main shaft, on the reliability of the component. The probabilistic reliability analysis conducted is based on fracture mechanics models. Additionally, the utilization of the probabilistic reliability for operation and maintenance planning and quality control is discussed.......One of the main challenges for the wind turbine industry currently, is to reduce the cost of levelized energy, especially for offshore wind. Failures in the wind turbine drivetrain generally result in the second largest down times of the wind turbine, hence significantly increasing the cost...

  16. Analysis of Impeller Type Wind Turbine

    Directory of Open Access Journals (Sweden)

    Ahmed y Qasim

    2011-12-01

    Full Text Available The new global development for wind turbines obliged inventors to create new wind turbine designs that have high efficiency and better than known designs. This paper proposes the impeller wind turbine, which uses more effectively the wind energy and depends only on the acting area of the vanes. The vane wind turbine is designed to increase the drag coefficient and output of a wind turbine that uses kinetic energy of the wind. It can be used worldwide due to its high efficiency, simple construction, and simple technology and can be made from cheap materials. Abstrak: Pembangunan global terkini turbin angin menyebabkan pereka harus membina rekaan terbaru turbin angin yang bercekapan tinggi yang lebih baik daripada rekaan-rekaan terdahulu. Kertas ini mencadangkan pendesak turbin angin, yang menggunakan kuasa angin secara lebih efektif dan bergantung hanya terhadap permukaan bilah kipas yang terlibat. Bilah kipas turbin angin direka sebegini untuk meningkatkan pekali seret dan juga keluaran daripada turbin angin tersebut yang menggunakan tenaga kinetik angin. Cara ini boleh digunakan secara meluas di serata dunia kerana ia bercekapan tinggi, mudah dibina, menggunakan teknologi yang ringkas dan diperbuat daripada bahan-bahan yang murah.

  17. Fault detection of a benchmark wind turbine using interval analysis

    DEFF Research Database (Denmark)

    Tabatabaeipour, Seyed Mojtaba; Odgaard, Peter Fogh; Bak, Thomas

    2012-01-01

    of the measurement with a closed set that is computed based on the past measurements and a model of the system. If the measurement is not consistent with this set, a fault is detected. The result demonstrates effectiveness of the method for fault detection of the benchmark wind turbine.......This paper investigates a state estimation set- membership approach for fault detection of a benchmark wind turbine. The main challenges in the benchmark are high noise on the wind speed measurement and the nonlinearities in the aerodynamic torque such that the overall model of the turbine...... is nonlinear. We use an effective wind speed estimator to estimate the effective wind speed and then using interval analysis and monotonicity of the aerodynamic torque with respect to the effective wind speed, we can apply the method to the nonlinear system. The fault detection algorithm checks the consistency...

  18. Failure Modes and Effects Analysis (FMEA) for wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Arabian-Hoseynabadi, H.; Oraee, H. [Department of Electrical Engineering, Sharif University of Technology, Tehran (Iran); Tavner, P.J. [Energy Group School of Engineering and Computing Sciences, Durham University (United Kingdom)

    2010-09-15

    The Failure Modes and Effects Analysis (FMEA) method has been used to study the reliability of many different power generation systems. This paper now applies that method to a wind turbine (WT) system using a proprietary software reliability analysis tool. Comparison is made between the quantitative results of an FMEA and reliability field data from real wind turbine systems and their assemblies. These results are discussed to establish relationships which are useful for future wind turbine designs. The main system studied is an existing design 2 MW wind turbine with a Doubly Fed Induction Generator (DFIG), which is then compared with a hypothetical wind turbine system using the Brushless Doubly Fed Generator (BDFG) of the same rating. The software reliability analysis tool used for these studies was Relex Reliability Studio 2007 Version 2. (author)

  19. Orthogonal Analysis Based Performance Optimization for Vertical Axis Wind Turbine

    Directory of Open Access Journals (Sweden)

    Lei Song

    2016-01-01

    Full Text Available Geometrical shape of a vertical axis wind turbine (VAWT is composed of multiple structural parameters. Since there are interactions among the structural parameters, traditional research approaches, which usually focus on one parameter at a time, cannot obtain performance of the wind turbine accurately. In order to exploit overall effect of a novel VAWT, we firstly use a single parameter optimization method to obtain optimal values of the structural parameters, respectively, by Computational Fluid Dynamics (CFD method; based on the results, we then use an orthogonal analysis method to investigate the influence of interactions of the structural parameters on performance of the wind turbine and to obtain optimization combination of the structural parameters considering the interactions. Results of analysis of variance indicate that interactions among the structural parameters have influence on performance of the wind turbine, and optimization results based on orthogonal analysis have higher wind energy utilization than that of traditional research approaches.

  20. Analysis of chaos in high-dimensional wind power system

    Science.gov (United States)

    Wang, Cong; Zhang, Hongli; Fan, Wenhui; Ma, Ping

    2018-01-01

    A comprehensive analysis on the chaos of a high-dimensional wind power system is performed in this study. A high-dimensional wind power system is more complex than most power systems. An 11-dimensional wind power system proposed by Huang, which has not been analyzed in previous studies, is investigated. When the systems are affected by external disturbances including single parameter and periodic disturbance, or its parameters changed, chaotic dynamics of the wind power system is analyzed and chaotic parameters ranges are obtained. Chaos existence is confirmed by calculation and analysis of all state variables' Lyapunov exponents and the state variable sequence diagram. Theoretical analysis and numerical simulations show that the wind power system chaos will occur when parameter variations and external disturbances change to a certain degree.

  1. Self-starting aerodynamics analysis of vertical axis wind turbine

    Directory of Open Access Journals (Sweden)

    Jianyang Zhu

    2015-12-01

    Full Text Available Vertical axis wind turbine is a special type of wind-force electric generator which is capable of working in the complicated wind environment. The self-starting aerodynamics is one of the most important considerations for this kind of turbine. This article aims at providing a systematic synthesis on the self-starting aerodynamic characteristics of vertical axis wind turbine based on the numerical analysis approach. First, the physical model of vertical axis wind turbine and its parameter definitions are presented. Secondary, the interaction model between the vertical axis wind turbine and fluid is developed by using the weak coupling approach; the numerical data of this model are then compared with the wind tunnel experimental data to show its feasibility. Third, the effects of solidity and fixed pitch angle on the self-starting aerodynamic characteristics of the vertical axis wind turbine are analyzed systematically. Finally, the quantification effects of the solidity and fixed pitch angle on the self-starting performance of the turbine can be obtained. The analysis in this study will provide straightforward physical insight into the self-starting aerodynamic characteristics of vertical axis wind turbine.

  2. Analysis of horizontal axis wind turbine blade using CFD

    African Journals Online (AJOL)

    A Pareto optimal multi-objective optimization for a horizontal axis wind turbine blade airfoil sections utilizing exergy analysis and neural networks. Journal of Wind Engineering and Industrial. Aerodynamics, Vol. 136, pp.62–72. Rajakumar S., Ravindran D. 2011 Iterative approach for optimising coefficient of power, coefficient ...

  3. Indian Ocean surface winds from NCMRWF analysis as compared to ...

    Indian Academy of Sciences (India)

    The quality of the surface wind analysis at the National Centre for Medium Range Weather Forecasts (NCMRWF), New Delhi over the tropical Indian Ocean and its improvement in 2001 are examined by comparing it with in situ buoy measurements and satellite derived surface winds from NASA QuikSCAT satellite (QSCT) ...

  4. statistical analysis of wind speed for electrical power generation in ...

    African Journals Online (AJOL)

    HOD

    are employed to fit wind speed data of some selected sites in Northern Nigeria. This is because the design of wind energy conversion systems depends on the correct analysis of the site renewable energy resources. [13]. In addition, the statistical judgements are based on the accuracy in fitting the available data at the sites.

  5. Reliability analysis of wind embedded power generation system for ...

    African Journals Online (AJOL)

    This paper presents a method for Reliability Analysis of wind energy embedded in power generation system for Indian scenario. This is done by evaluating the reliability index, loss of load expectation, for the power generation system with and without integration of wind energy sources in the overall electric power system.

  6. Indian Ocean surface winds from NCMRWF analysis as compared to ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    The quality of the surface wind analysis at the National Centre for Medium Range Weather Fore- casts (NCMRWF), New Delhi over the tropical Indian Ocean and its improvement in 2001 are examined by comparing it with in situ buoy measurements and satellite derived surface winds from. NASA QuikSCAT satellite (QSCT) ...

  7. Performance analysis of voltage regulation in diesel-wind generation

    African Journals Online (AJOL)

    user

    2006-05-04

    May 4, 2006 ... Abstract. In presented paper performance analysis of the hybrid diesel-wind energy conversion system has presented. Electrical energy is generated by the two sources one source is the diesel engine generator and the other source is the wind energy conversion system the supply is provided to the ...

  8. Directional analysis of extreme winds under mixed climate conditions

    CSIR Research Space (South Africa)

    Kruger, A

    2013-07-01

    Full Text Available -1 European-African Conference on Wind Engineering 2013, Robinson College, Cambridge, July 2013 Directional Analysis of Extreme Winds under Mixed Climate Conditions *Andries Kruger1, Adam Goliger2 and Johan Retief3 1Climate Service, South African...

  9. Continuous Software Quality analysis for the ATLAS experiment

    CERN Document Server

    Washbrook, Andrew; The ATLAS collaboration

    2017-01-01

    The regular application of software quality tools in large collaborative projects is required to reduce code defects to an acceptable level. If left unchecked the accumulation of defects invariably results in performance degradation at scale and problems with the long-term maintainability of the code. Although software quality tools are effective for identification there remains a non-trivial sociological challenge to resolve defects in a timely manner. This is a ongoing concern for the ATLAS software which has evolved over many years to meet the demands of Monte Carlo simulation, detector reconstruction and data analysis. At present over 3.8 million lines of C++ code (and close to 6 million total lines of code) are maintained by a community of hundreds of developers worldwide. It is therefore preferable to address code defects before they are introduced into a widely used software release. Recent wholesale changes to the ATLAS software infrastructure have provided an ideal opportunity to apply software quali...

  10. 2014 Offshore Wind Market and Economic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, Bruce [Navigant Consulting, Inc., Burlington, MA (United States)

    2014-08-25

    The objective of this report is to provide a comprehensive annual assessment of the U.S. offshore wind market.This 3rd annual report focuses on new developments that have occurred in 2014. The report provides stakeholders with a reliable and consistent data source addressing entry barriers and U.S. competitiveness in the offshore wind market. Available for download are both the full report and the report's underlying data.

  11. Overview of software products for the terrain analysis in the tasks of design automation of wind-power stations

    Directory of Open Access Journals (Sweden)

    Volkov Andrey Anatol’evich

    2014-03-01

    Full Text Available The lack of ground and constantly growing price for energy sources are the reason for using alternative energy. The rules of the world community for environmental protection is the motivation for using renewable energy sources. It is necessary to automate the processes of the design technology for the alternative energy structures and their operation, as well as data gathering and analisys on all the existing objects. There is also the need to automise these objects' management. The topic of this article is connected to the analysis of terrain for designing windpower stations. The regional wind maps are valuable tools for the wind farm developer for searching site, but they are not accurate enough to justify the financing of the development. For the majority of prospective wind farms, the developer must undertake a wind resource measurement and use analyzing program. This should provide a robust prediction of the expected energy production over its lifetime. The authors note that a prediction of the energy production of a wind farm is possible using such methods as the wind atlas methodology within WAsP and show the main instruments.

  12. Transient performance analysis of wind-power induction generators

    OpenAIRE

    Seman, Slavomir

    2006-01-01

    A coupled field-circuit simulator for the transient analysis of wind energy conversion systems with a doubly fed induction generator (DFIG) was developed and experimentally validated. Short-term grid disturbance and ride-through analyses were carried out for a 1.7-MW DFIG wind-power conversion system. Two simulation models of the wind-power DFIG were compared to reveal the consequences of the different modeling approaches for the accuracy of transient analysis. The DFIG was represented in the...

  13. Structural Reliability Analysis of Wind Turbines: A Review

    Directory of Open Access Journals (Sweden)

    Zhiyu Jiang

    2017-12-01

    Full Text Available The paper presents a detailed review of the state-of-the-art research activities on structural reliability analysis of wind turbines between the 1990s and 2017. We describe the reliability methods including the first- and second-order reliability methods and the simulation reliability methods and show the procedure for and application areas of structural reliability analysis of wind turbines. Further, we critically review the various structural reliability studies on rotor blades, bottom-fixed support structures, floating systems and mechanical and electrical components. Finally, future applications of structural reliability methods to wind turbine designs are discussed.

  14. An optimal sizing method for energy storage system in wind farms based on the analysis of wind power forecast error

    Science.gov (United States)

    Ye, R. L.; Guo, Z. Z.; Liu, R. Y.; Liu, J. N.

    2016-11-01

    Energy storage system (ESS) in a wind farm can effectively compensate the fluctuations of wind power. How to determine the size of ESS in wind farms is an urgent problem to be solved. A novel method is proposed for designing the optimal size of ESS considering wind power uncertainty. This approach uses non-parametric estimation method to analysis the wind power forecast error (WPFE) and the cumulative wind power deviation (CWPD) within the scheduling period. Then a cost-benefit analysis model is established to obtain the optimal size of ESS based on the analysis of WPFE and CWPD. A series of wind farm data in California are used as numerical cases, which presents that the algorithm presented in this paper has good feasibility and performance in optimal ESS sizing in wind farms.

  15. Wear Analysis of Wind Turbine Gearbox Bearings

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL; Walker, Larry R [ORNL; Xu, Hanbing [ORNL; Parten, Randy J [ORNL; Qu, Jun [ORNL; Geer, Tom [ORNL

    2010-04-01

    The objective of this effort was to investigate and characterize the nature of surface damage and wear to wind turbine gearbox bearings returned from service in the field. Bearings were supplied for examination by S. Butterfield and J. Johnson of the National Wind Technology Center (NREL), Boulder, Colorado. Studies consisted of visual examination, optical and electron microscopy, dimensional measurements of wear-induced macro-scale and micro-scale features, measurements of macro- and micro-scale hardness, 3D imaging of surface damage, studies of elemental distributions on fracture surfaces, and examinations of polished cross-sections of surfaces under various etched and non-etched conditions.

  16. Analysis of a commercial wind farm in Taiwan

    DEFF Research Database (Denmark)

    Wang, Li; Yeh, Tai-Her; Lee, Wei-Jen

    2009-01-01

    This paper presents steady-state performance analysis of a commercial wind farm in Taiwan through field measurement results and computer simulations. The companion paper in Part II discusses the employment of current-limit reactors and load tap changers on power-quality improvement of the studied...... wind farm. With twenty-three 2-MW DFIG-type wind turbine generators, this wind farm is connected to the 161-kV extra high-voltage substation of Taiwan Power System through a 23/161-kV, 60-MVA step-up main transformer from six feeders. Through comparing field measured results, this paper establishes...... a simulation model to simulate and analyze the steady-state characteristics of the studied wind farm under disturbance conditions....

  17. Reliability Analysis of Fatigue Fracture of Wind Turbine Drivetrain Components

    DEFF Research Database (Denmark)

    Berzonskis, Arvydas; Sørensen, John Dalsgaard

    2016-01-01

    in the volume of the casted ductile iron main shaft, on the reliability of the component. The probabilistic reliability analysis conducted is based on fracture mechanics models. Additionally, the utilization of the probabilistic reliability for operation and maintenance planning and quality control is discussed....... of operation and maintenance. The manufacturing of casted drivetrain components, like the main shaft of the wind turbine, commonly result in many smaller defects through the volume of the component with sizes that depend on the manufacturing method. This paper considers the effect of the initial defect present......One of the main challenges for the wind turbine industry currently, is to reduce the cost of levelized energy, especially for offshore wind. Failures in the wind turbine drivetrain generally result in the second largest down times of the wind turbine, hence significantly increasing the cost...

  18. Wind Power in Mexico: Simulation of a Wind Farm and Application of Probabilistic Safety Analysis

    Directory of Open Access Journals (Sweden)

    C. Martín del Campo–Márquez

    2009-10-01

    Full Text Available The most important aspects of wind energy in Mexico, including the potential for generating electricity and the major projects planned are presented here. Inparticular, the generation costs are compared to those of other energy sources. The results from the simulation of a 100 MWwind farm in the Tehuantepec Isthmus are also presented. In addition, the environmental impacts related to the wind farm in the mentioned zone are analyzed. Finally, some benefits of using Probabilistic Safety Analysis are discussed with respect to evaluating the risks associated with events that can occur in wind parks, being especially useful for design and maintenance of the parks and the wind turbines themselves. In particular, an event tree was developed to analyze possible accident sequences that could occur when the wind speed is too great. Also, fault trees were developed for each mitigating system considered, in order to determine the relative importance of the wind generator components to the failure sequences, in order to evaluate the yield of suggested improvements and the optimization of maintenance programs.

  19. Harmonic Analysis of Offshore Wind Farms with Full Converter Wind Turbines

    DEFF Research Database (Denmark)

    Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth

    2009-01-01

    This paper presents the harmonic analysis of offshore wind farm (OWF) models with full converters represented as harmonic sources and measurement data on the point of common coupling (PCC) during normal operation. The model describes a wind farm (WF) with full rated converters installed connected...... to a shore with a long HV cable. The way of propagation and effects of harmonics are presented for different study cases. Modeling strategies of harmonic sources for harmonic analysis are described and compared. Different results dependent on applied harmonic models are shown and discussed in this paper...

  20. Aerofoil flutter: fluid-mechanical analysis and wind tunnel testing

    Science.gov (United States)

    Wensuslaus, A. L.; McMillan, A. J.

    2012-08-01

    This paper describes a three dimensional wing model, which has been developed for the purpose of studying flutter, both computationally and through wind tunnel testing. A three dimensional, laminar flow aerofoil wing, based on the NACA aerofoil has been designed. The natural frequencies for this aerofoil were obtained through modal analysis. A scale model wing, without taper was manufactured in the laboratory and tested in a wind tunnel. The pressure data was obtained from fluid flow analysis and the deformation results obtained through structural analysis. The analysis was performed in the ANSYS Workbench Environment, accessing FLUENT CFX for the computational fluid dynamics analysis and the ANSYS FEA package for the mechanical analysis. The computational results obtained are compared with the experimental data obtained in the wind tunnel. Comparison of the analysis and test results provides further understanding of the flutter characteristics.

  1. Fatigue Analysis of Large-scale Wind turbine

    Directory of Open Access Journals (Sweden)

    Zhu Yongli

    2017-01-01

    Full Text Available The paper does research on top flange fatigue damage of large-scale wind turbine generator. It establishes finite element model of top flange connection system with finite element analysis software MSC. Marc/Mentat, analyzes its fatigue strain, implements load simulation of flange fatigue working condition with Bladed software, acquires flange fatigue load spectrum with rain-flow counting method, finally, it realizes fatigue analysis of top flange with fatigue analysis software MSC. Fatigue and Palmgren-Miner linear cumulative damage theory. The analysis result indicates that its result provides new thinking for flange fatigue analysis of large-scale wind turbine generator, and possesses some practical engineering value.

  2. What Is the Most Representative Parameter for Describing the Size of the Atlas? CT Morphometric Analysis of the Atlas with Special Reference to Atlas Hypoplasia.

    Science.gov (United States)

    Yamahata, Hitoshi; Hirano, Hirofumi; Yamaguchi, Satoshi; Mori, Masanao; Niiro, Tadaaki; Tokimura, Hiroshi; Arita, Kazunori

    2017-09-15

    The spinal canal diameter (SCD) is one of the most studied factors for the assessment of cervical spinal canal stenosis. The inner anteroposterior diameter (IAP), the SCD, and the cross-sectional area (CSA) of the atlas have been used for the evaluation of the size of the atlas in patients with atlas hypoplasia, a rare form of developmental spinal canal stenosis, however, there is little information on their relationship. The aim of this study was to identify the most useful parameter for depicting the size of the atlas. The CSA, the IAP, and the SCD were measured on computed tomography (CT) images at the C1 level of 213 patients and compared in this retrospective study. These three parameters increased with increasing patient height and weight. There was a strong correlation between IAP and SCD (r = 0.853) or CSA (r = 0.822), while correlation between SCD and CSA (r = 0.695) was weaker than between IAP and CSA. Partial correlation analysis showed that IAP was positively correlated with SCD (r = 0.687) and CSA (r = 0.612) when CSA or SCD were controlled. SCD was negatively correlated with CSA when IAP was controlled (r = -0.21). The IAP can serve as the CSA for the evaluation of the size of the atlas ring, while the SCD does not correlate with the CSA. As the patient height and weight affect the size of the atlas, analysis of the spinal canal at the C1 level should take into account physiologic patient data.

  3. Proposed Wind Turbine Aeroelasticity Studies Using Helicopter Systems Analysis

    Science.gov (United States)

    Ladkany, Samaan G.

    1998-01-01

    Advanced systems for the analysis of rotary wing aeroelastic structures (helicopters) are being developed at NASA Ames by the Rotorcraft Aeromechanics Branch, ARA. The research has recently been extended to the study of wind turbines, used for electric power generation Wind turbines play an important role in Europe, Japan & many other countries because they are non polluting & use a renewable source of energy. European countries such as Holland, Norway & France have been the world leaders in the design & manufacture of wind turbines due to their historical experience of several centuries, in building complex wind mill structures, which were used in water pumping, grain grinding & for lumbering. Fossil fuel cost in Japan & in Europe is two to three times higher than in the USA due to very high import taxes. High fuel cost combined with substantial governmental subsidies, allow wind generated power to be competitive with the more traditional sources of power generation. In the USA, the use of wind energy has been limited mainly because power production from wind is twice as expensive as from other traditional sources. Studies conducted at the National Renewable Energy Laboratories (NREL) indicate that the main cost in the production of wind turbines is due to the materials & the labor intensive processes used in the construction of turbine structures. Thus, for the US to assume world leadership in wind power generation, new lightweight & consequently very flexible wind turbines, that could be economically mass produced, would have to be developed [4,5]. This effort, if successful, would result in great benefit to the US & the developing nations that suffer from overpopulation & a very high cost of energy.

  4. Aeroelastic Ground Wind Loads Analysis Tool for Launch Vehicles

    Science.gov (United States)

    Ivanco, Thomas G.

    2016-01-01

    Launch vehicles are exposed to ground winds during rollout and on the launch pad that can induce static and dynamic loads. Of particular concern are the dynamic loads caused by vortex shedding from nearly-cylindrical structures. When the frequency of vortex shedding nears that of a lowly-damped structural mode, the dynamic loads can be more than an order of magnitude greater than mean drag loads. Accurately predicting vehicle response to vortex shedding during the design and analysis cycles is difficult and typically exceeds the practical capabilities of modern computational fluid dynamics codes. Therefore, mitigating the ground wind loads risk typically requires wind-tunnel tests of dynamically-scaled models that are time consuming and expensive to conduct. In recent years, NASA has developed a ground wind loads analysis tool for launch vehicles to fill this analytical capability gap in order to provide predictions for prelaunch static and dynamic loads. This paper includes a background of the ground wind loads problem and the current state-of-the-art. It then discusses the history and significance of the analysis tool and the methodology used to develop it. Finally, results of the analysis tool are compared to wind-tunnel and full-scale data of various geometries and Reynolds numbers.

  5. Analysis of the Environmental Impact on Remanufacturing Wind Turbines

    Science.gov (United States)

    Sosa Skrainka, Manuel R.

    To deliver clean energy the use of wind turbines is essential. In June 2011 there was an installed wind capacity equivalent to 211,000MW world-wide (WWEA, 2011). By the end of the year 2009 the U.S. had 35,100MW of wind energy installed capacity to generate electricity (AWEA, 2010). This industry has grown in recent years and is expected to grow even more in the future. The environmental impacts that will arise from the increased number of wind turbines and their end-of-life should be addressed, as large amounts of resources will be required to satisfy the current and future market demands for wind turbines. Since future 10MW wind turbines are expected to be as heavy as 1000 tons each, the study of the environmental response of profitable retirement strategies, such as remanufacturing for these machines, must be considered. Because of the increased number of wind turbines and the materials used, this study provides a comparison between the environmental impacts from remanufacturing the components installed inside the nacelle of multi-megawatt wind turbines and wind turbines manufactured using new components. The study methodology is the following: • Describe the life-cycle and the materials and processes employed for the manufacture and remanufacturing for components inside the nacelle. • Identify remanufacturing alternatives for the components inside the nacelle at the end of the expected life-time service of wind turbines. • Evaluate the environmental impacts from the remanufactured components and compare the results with the impacts of the manufacturing of new components using SimaPro. • Conduct sensitivity analysis over the critical parameters of the life cycle assessment • Propose the most environmentally friendly options for the retirement of each major component of wind turbines. After an analysis of the scenarios the goal of the study is to evaluate remanufacturing as an end-of-life option from an environmental perspective for commercial multi

  6. Lightning transient analysis in wind turbine blades

    DEFF Research Database (Denmark)

    Candela Garolera, Anna; Holbøll, Joachim; Madsen, Søren Find

    2013-01-01

    The transient behavior of lightning surges in the lightning protection system of wind turbine blades has been investigated in this paper. The study is based on PSCAD models consisting of electric equivalent circuits with lumped and distributed parameters involving different lightning current...... and other internal conductive elements of the blade is studied. Finally, several methods to prevent internal arcing are discussed in order to improve the lightning protection of the blade....

  7. Electromagnetic Cyclotron Waves in the Solar Wind: Wind Observation and Wave Dispersion Analysis

    Science.gov (United States)

    Jian, L. K.; Moya, P. S.; Vinas, A. F.; Stevens, M.

    2016-01-01

    Wind observed long-lasting electromagnetic cyclotron waves near the proton cyclotron frequency on 11 March 2005, in the descending part of a fast wind stream. Bi-Maxwellian velocity distributions are fitted for core protons, beam protons, and alpha-particles. Using the fitted plasma parameters we conduct kinetic linear dispersion analysis and find ion cyclotron and/or firehose instabilities grow in six of 10 wave intervals. After Doppler shift, some of the waves have frequency and polarization consistent with observation, thus may be correspondence to the cyclotron waves observed.

  8. Statistical and Spectral Analysis of Wind Characteristics Relevant to Wind Energy Assessment Using Tower Measurements in Complex Terrain

    Directory of Open Access Journals (Sweden)

    Radian Belu

    2013-01-01

    Full Text Available The main objective of the study was to investigate spatial and temporal characteristics of the wind speed and direction in complex terrain that are relevant to wind energy assessment and development, as well as to wind energy system operation, management, and grid integration. Wind data from five tall meteorological towers located in Western Nevada, USA, operated from August 2003 to March 2008, used in the analysis. The multiannual average wind speeds did not show significant increased trend with increasing elevation, while the turbulence intensity slowly decreased with an increase were the average wind speed. The wind speed and direction were modeled using the Weibull and the von Mises distribution functions. The correlations show a strong coherence between the wind speed and direction with slowly decreasing amplitude of the multiday periodicity with increasing lag periods. The spectral analysis shows significant annual periodicity with similar characteristics at all locations. The relatively high correlations between the towers and small range of the computed turbulence intensity indicate that wind variability is dominated by the regional synoptic processes. Knowledge and information about daily, seasonal, and annual wind periodicities are very important for wind energy resource assessment, wind power plant operation, management, and grid integration.

  9. Quantifying offshore wind resources from satellite wind maps: Study area the North Sea

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay; Barthelmie, Rebecca Jane; Christiansen, Merete B.

    2006-01-01

    analysis and application program (WAsP). An estimate of the wind resource at the new project site at Horns Rev is given based on satellite SAR observations. The comparison of offshore satellite scatterometer winds, global model data and in situ data shows good agreement. Furthermore, the wake effect......Offshore wind resources are quantified from satellite synthetic aperture radar (SAR) and satellite scatterometer observations at local and regional scale respectively at the Horns Rev site in Denmark. The method for wind resource estimation from satellite observations interfaces with the wind atlas...

  10. The German National Analysis Facility as a tool for ATLAS analyses

    CERN Document Server

    Mehlhase, S; The ATLAS collaboration; Leffhalm, K

    2010-01-01

    In 2008 the German National Analysis Facility (NAF) at DESY was established. It is attached to and builds on top of the DESY Grid infrastructure. The facility was designed to provide the best possible analysis infrastructure for high energy particle physics of the ATLAS, CMS, LHCb and ILC experiments. The Grid and local infrastructure of the German NAF will be reviewed with a focus on the ATLAS part. Both parts include large scale storage and a batch system. The main emphasis of this presentation is the ATLAS specific customisation and utilisation of the NAF. This refers not only to the NAF components but also to the different components of the ATLAS analysis framework. Experience from operating and supporting ATLAS users on the German NAF will be presented. The ATLAS usage of the different components will be shown including some typical use cases of user analysis. Finally, the question will be addressed if the design of the NAF meets the ATLAS expectations for efficient data analysis in the era of LHC data t...

  11. 1 The German National Analysis Facility as a tool for ATLAS analyses

    CERN Document Server

    Mehlhase, S; The ATLAS collaboration; Leffhalm, K

    2011-01-01

    In 2008 the German National Analysis Facility (NAF) at DESY was established. It is attached to and builds on top of DESY Grid infrastructure. The facility is designed to provide the best possible analysis infrastructure for high energy particle physics of the ATLAS, CMS, LHCb and ILC experiments. The Grid and local infrastructure of the NAF is reviewed with a focus on the ATLAS part. Both parts include large scale storage and a batch system. Emphasis is put on ATLAS specific customisation and utilisation of the NAF. This refers not only to the NAF components but also to the di erent components of the ATLAS analysis framework. Experience from operating and supporting ATLAS users on the NAF is presented in this paper. The ATLAS usage of the di erent components are shown including some typical use cases of user analysis. Finally, the question is addressed, if the design of the NAF meets the ATLAS expectations for effcient data analysis in the era of LHC data taking.

  12. Evaluation of RCAS Inflow Models for Wind Turbine Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tangler, J.; Bir, G.

    2004-02-01

    The finite element structural modeling in the Rotorcraft Comprehensive Analysis System (RCAS) provides a state-of-the-art approach to aeroelastic analysis. This, coupled with its ability to model all turbine components, results in a methodology that can simulate complex system interactions characteristic of large wind. In addition, RCAS is uniquely capable of modeling advanced control algorithms and the resulting dynamic responses.

  13. Steps towards a SAR-based wind atlas in the Baltic Sea

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay; Badger, Merete; Pena Diaz, Alfredo

    deviation of 1.88 m/s (20.11°), and linear correlation coefficient R2 of 0.783 (0.95°). The second step was estimation of the mean wind speed, the Weibull scale and shape parameters, and energy density based on over 1000 SAR-based wind maps for the Baltic Sea. The results were compared to the FINO-2...... of distance to nearest coast was also investigated (Hasager et al. 2011). The third step is focused on lifting SAR-based winds from 10 m to hub-height using a method proposed and applied to a data set in the North Sea by Badger et al. 2012 (EWEA 2012 conference). In brief, the method is based on information...

  14. Detection of Wind Turbine Power Performance Abnormalities Using Eigenvalue Analysis

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Sweeney, Christian Walsted; Marhadi, Kun Saptohartyadi

    2014-01-01

    , are commercially available and functioning successfully in fixed speed and vari- able speed turbines. Power performance analysis is a method specifically applicable to wind turbines for the detection of power generation changes due to external factors, such as ic- ing, internal factors, such as controller...... malfunction, or delib- erate actions, such as power de-rating. In this paper, power performance analysis is performed by sliding a time-power window and calculating the two eigenvalues corresponding to the two dimensional wind speed - power generation dis- tribution. The power is classified into five bins......Condition monitoring of wind turbines is a field of continu- ous research and development as new turbine configurations enter into the market and new failure modes appear. Systems utilising well established techniques from the energy and in- dustry sector, such as vibration analysis...

  15. Description of the Probabilistic Wind Atlas Methodology, Deliverable D3.1

    DEFF Research Database (Denmark)

    Hahmann, Andrea N.; Witha, Björn; Rife, Daran L.

    A new ensemble method is explored for estimating the uncertainty of the wind resource within Weather Research and Forecasting (WRF) model simulations. The output of the ensemble simulations is processed to create a "map" showing the uncertainty in the wind resource estimate at each geographic...... location. This new method is demonstrated by performing a collection of 9 different WRF model simulations using combinations of 3 planetary boundary layer schemes, 2 simulation re-initialization strategies, and 2 methods for initializing the land surface state. The results of the simulations are validated...

  16. Uncertainty analysis of wind-wave predictions in Lake Michigan

    Science.gov (United States)

    Nekouee, Navid; Ataie-Ashtiani, Behzad; Hamidi, Sajad Ahmad

    2016-10-01

    With all the improvement in wave and hydrodynamics numerical models, the question rises in our mind that how the accuracy of the forcing functions and their input can affect the results. In this paper, a commonly used numerical third-generation wave model, SWAN is applied to predict waves in Lake Michigan. Wind data are analyzed to determine wind variation frequency over Lake Michigan. Wave predictions uncertainty due to wind local effects are compared during a period where wind has a fairly constant speed and direction over the northern and southern basins. The study shows that despite model calibration in Lake Michigan area, the model deficiency arises from ignoring wind effects in small scales. Wave prediction also emphasizes that small scale turbulence in meteorological forces can increase prediction errors by 38%. Wave frequency and coherence analysis show that both models can predict the wave variation time scale with the same accuracy. Insufficient number of meteorological stations can result in neglecting local wind effects and discrepancies in current predictions. The uncertainty of wave numerical models due to input uncertainties and model principals should be taken into account for design risk factors.

  17. CFD Analysis On The Performance Of Wind Turbine With Nozzles

    OpenAIRE

    Chunkyraj Kh; C. D. Hampali; Anand S. N.

    2015-01-01

    In this paper an effort has been made in dealing with fluid characteristic that enters a converging nozzle and analysis of the nozzle is carried out using Computational Fluid Dynamics package ANSYS WORKBENCH 14.5. The paper is the continuation of earlier work Analytical and Experimental performance evaluation of Wind turbine with Nozzles. First the CFD analysis will be carried out on nozzle in-front of wind turbine where streamline velocity at the exit volume flow rate in the nozzle and press...

  18. Analysis of wind energy potential and vibrations caused by wind turbine on its basement

    OpenAIRE

    Kaláb, Zdeněk; Hanslian, David; Stolárik, Martin; Pinka, Miroslav

    2014-01-01

    This paper deals with study of wind energy potential and experimental measurement of vibrations caused by wind turbine. Study area was wind park Horní Loděnice – Lipina. To obtain frequency distribution of wind speed, two models were used for calculation. Experimental seismological measurement was performed in near surroundings of the wind turbine. At low wind speed without significant wind gust, only negligible vibrations were measured. Web of Science 19 3 159 151

  19. Wind atlas for South Africa (WASA): Project overview and current status

    CSIR Research Space (South Africa)

    Szewczuk, S

    2010-08-31

    Full Text Available The goal of the South African Wind Energy Programme (SAWEP) is to reduce greenhouse gas emissions generated by thermal power in the national inter-connected system. SAWEP has six main expected outcomes: increased public sector incremental cost...

  20. Design analysis of vertical wind turbine with airfoil variation

    Science.gov (United States)

    Maulana, Muhammad Ilham; Qaedy, T. Masykur Al; Nawawi, Muhammad

    2016-03-01

    With an ever increasing electrical energy crisis occurring in the Banda Aceh City, it will be important to investigate alternative methods of generating power in ways different than fossil fuels. In fact, one of the biggest sources of energy in Aceh is wind energy. It can be harnessed not only by big corporations but also by individuals using Vertical Axis Wind Turbines (VAWT). This paper presents a three-dimensional CFD analysis of the influence of airfoil design on performance of a Darrieus-type vertical-axis wind turbine (VAWT). The main objective of this paper is to develop an airfoil design for NACA 63-series vertical axis wind turbine, for average wind velocity 2,5 m/s. To utilize both lift and drag force, some of designs of airfoil are analyzed using a commercial computational fluid dynamics solver such us Fluent. Simulation is performed for this airfoil at different angles of attach rearranging from -12°, -8°, -4°, 0°, 4°, 8°, and 12°. The analysis showed that the significant enhancement in value of lift coefficient for airfoil NACA 63-series is occurred for NACA 63-412.

  1. Wind Turbine Control Impact on Stability of Wind Farms Based on Real-Life Systems Analysis

    DEFF Research Database (Denmark)

    Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth

    2012-01-01

    that wind farm components such as long HVAC cables and park transformers can introduce significant low-frequency series resonances seen form the wind turbine terminals which can affect wind turbine control system operation and overall wind farm stability. The same wind turbine converter control strategy...

  2. Analysis of empty ATLAS pilot jobs

    Science.gov (United States)

    Love, P. A.; Alef, M.; Dal Pra, S.; Di Girolamo, A.; Forti, A.; Templon, J.; Vamvakopoulos, E.; ATLAS Collaboration

    2017-10-01

    In this analysis we quantify the wallclock time used by short empty pilot jobs on a number of WLCG compute resources. Pilot factory logs and site batch logs are used to provide independent accounts of the usage. Results show a wide variation of wallclock time used by short jobs depending on the site and queue, and changing with time. For a reference dataset of all jobs in August 2016, the fraction of wallclock time used by empty jobs per studied site ranged from 0.1% to 0.8%. Aside from the wall time used by empty pilots, we also looked at how many pilots were empty as a fraction of all pilots sent. Binning the August dataset into days, empty fractions between 2% and 90% were observed. The higher fractions correlate well with periods of few actual payloads being sent to the site.

  3. Analysis of empty ATLAS pilot jobs

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00006364; The ATLAS collaboration; Dal Pra, S.; Di Girolamo, A.; Forti, A.; Templon, J.; Vamvakopoulos, E.

    2017-01-01

    In this analysis we quantify the wallclock time used by short empty pilot jobs on a number of WLCG compute resources. Pilot factory logs and site batch logs are used to provide independent accounts of the usage. Results show a wide variation of wallclock time used by short jobs depending on the site and queue, and changing with time. For a reference dataset of all jobs in August 2016, the fraction of wallclock time used by empty jobs per studied site ranged from 0.1% to 0.8%. The variation in wallclock usage may be explained by different workloads for each resource with a greater fraction when the workload is low. Aside from the wall time used by empty pilots, we also looked at how many pilots were empty as a fraction of all pilots sent. Binning the August dataset into days, empty fractions between 2% and 90% were observed.  The higher fractions correlate well with periods of few actual payloads being sent to the site.

  4. Auto-correlation analysis of ocean surface wind vectors

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    A case study using the TRMM Microwave Imager (TMI) and. Indian Ocean buoy wind speed data resulted in an ... parameter, measured by different instruments, sep- arated in time (or space) from each other, are .... nique for objective analysis and design of oceanographic experiments applied to MODE-73; Deep Sea Res.

  5. Design of airborne wind turbine and computational fluid dynamics analysis

    Science.gov (United States)

    Anbreen, Faiqa

    Wind energy is a promising alternative to the depleting non-renewable sources. The height of the wind turbines becomes a constraint to their efficiency. Airborne wind turbine can reach much higher altitudes and produce higher power due to high wind velocity and energy density. The focus of this thesis is to design a shrouded airborne wind turbine, capable to generate 70 kW to propel a leisure boat with a capacity of 8-10 passengers. The idea of designing an airborne turbine is to take the advantage of higher velocities in the atmosphere. The Solidworks model has been analyzed numerically using Computational Fluid Dynamics (CFD) software StarCCM+. The Unsteady Reynolds Averaged Navier Stokes Simulation (URANS) with K-epsilon turbulence model has been selected, to study the physical properties of the flow, with emphasis on the performance of the turbine and the increase in air velocity at the throat. The analysis has been done using two ambient velocities of 12 m/s and 6 m/s. At 12 m/s inlet velocity, the velocity of air at the turbine has been recorded as 16 m/s. The power generated by the turbine is 61 kW. At inlet velocity of 6 m/s, the velocity of air at turbine increased to 10 m/s. The power generated by turbine is 25 kW.

  6. Analysis of wind data for airport runway design

    Directory of Open Access Journals (Sweden)

    Roberto Bellasio

    2014-09-01

    Full Text Available Purpose: To provide a methodology, and examples of application, for analyzing wind data for the correct orientation of airport runways. Design/methodology/approach: More than 90000 observed wind data have been analyzed for each one of the three airports used as case studies. Both observed and estimated gusts have been considered. Findings: If only observed data are considered, each single runway of the three airports used as case studies is correctly oriented. When estimated gusts are considered, the FAA requirements are not satisfied by a single runway in some airports (which anyway satisfy such requirements by using more runways. Practical implications: The correct orientation of runways minimize the crosswind components, then increase the safety of the airports. Originality/value: The paper provides a methodology to evaluate the orientation of existing runways and to design new runways. Such methodology is based on the analysis wind data, considering both observed values and estimated gusts.

  7. SMART wind turbine rotor. Data analysis and conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Jonathan Charles; Barone, Matthew Franklin; Yoder, Nathanael C.

    2014-01-01

    The Wind Energy Technologies department at Sandia National Laboratories has developed and field tested a wind turbine rotor with integrated trailing-edge flaps designed for active control of the rotor aerodynamics. The SMART Rotor project was funded by the Wind and Water Power Technologies Office of the U.S. Department of Energy (DOE) and was conducted to demonstrate active rotor control and evaluate simulation tools available for active control research. This report documents the data post-processing and analysis performed to date on the field test data. Results include the control capability of the trailing edge flaps, the combined structural and aerodynamic damping observed through application of step actuation with ensemble averaging, direct observation of time delays associated with aerodynamic response, and techniques for characterizing an operating turbine with active rotor control.

  8. Experiment and Analysis of Car Alternator for Wind Turbine Application

    Directory of Open Access Journals (Sweden)

    Pudji Irasari

    2012-03-01

    Full Text Available This paper discusses experiment and analysis to find out the feasibility of a car alternator to be used as a generator for wind turbine. The experiment was conducted twice. The first experiment was to characterize the alternator to determine the mechanical transmission ratio. In this experiment the alternator was driven by a lathe machine and its output power was supplied to charge a battery. In the second experiment the alternator was integrated with the turbine blades and they were tested as a unit system. In both experiments, the electric generation of alternator was executed with fixed excitation current method. The correlation between the alternator characteristic and the tip speed ratio gives the mechanical transmission ratio of 1 : 3. The experiment results show that the efficiency of alternator is around 50% and cut-in wind speed (after correction is 6.35 m/s indicating that alternator is not feasible for wind turbine system application. 

  9. Analysis of wind conditions on the Faroe islands based on roadside wind measurements and WASP

    Science.gov (United States)

    Beyer, Hans Georg; Niclasen, Bardur; Eyðfinnsson Veyhe, Torkil

    2017-04-01

    For the Faroe Islands - intending to increase the share of wind energy to the electricity supply - a comprehensive mapping of the wind potential is missing up to today. With dedicated meteorological measurements missing, source for site wind data are formed by a set of meteorological stations with 10m above ground wind measurements intended to monitor road conditions. Stations are thus -due to the complex topography of the islands - mostly positioned at locations not optimal for wind energy studies. We will describe the attempt to use these data for a scanning of the wind energy relevant information in view of both wind energy potential and design relevant extreme wind gusts.

  10. Wind tunnel data of the analysis of heat pipe and wind catcher technology for the built environment.

    Science.gov (United States)

    Calautit, John Kaiser; Chaudhry, Hassam Nasarullah; Hughes, Ben Richard

    2015-12-01

    The data presented in this article were the basis for the study reported in the research articles entitled 'Climate responsive behaviour heat pipe technology for enhanced passive airside cooling' by Chaudhry and Hughes [10] which presents the passive airside cooling capability of heat pipes in response to gradually varying external temperatures and related to the research article "CFD and wind tunnel study of the performance of a uni-directional wind catcher with heat transfer devices" by Calautit and Hughes [1] which compares the ventilation performance of a standard roof mounted wind catcher and wind catcher incorporating the heat pipe technology. Here, we detail the wind tunnel test set-up and inflow conditions and the methodologies for the transient heat pipe experiment and analysis of the integration of heat pipes within the control domain of a wind catcher design.

  11. Stability analysis of offshore wind farm and marine current farm

    Science.gov (United States)

    Shawon, Mohammad Hasanuzzaman

    -trend for large electric energy production using offshore wind generators and marine current generators, respectively. Thus DFIG based offshore wind farm can be an economic solution to stabilize squirrel cage induction generator based marine current farm without installing any addition FACTS devices. This thesis first focuses on the stabilization of fixed speed IG based marine current farm using SDBR. Also stabilization of DFIG based variable speed wind farm utilizing SDBR is studied in this work. Finally a co-operative control strategy is proposed where DFIG is controlled in such a way that it can even provide necessary reactive power demand of induction generator, so that additional cost of FACTS devices can be avoided. In that way, the DFIGs of the offshore wind farm (OWF) will actively compensate the reactive power demand of adjacent IGs of the marine current farm (MCF) during grid fault. Detailed modeling and control scheme for the proposed system are demonstrated considering some realistic scenarios. The power system small signal stability analysis is also carried out by eigenvalue analysis for marine current generator topology, wind turbine generator topology and integrated topology. The relation between the modes and state variables are discussed in light of modal and sensitivity analyses. The results of theoretical analyses are verified by MATLAB/SIMULINK and laboratory standard power system simulator PSCAD/EMTDC.

  12. Development of a site analysis tool for distributed wind projects

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Shawn [The Cadmus Group, Inc., Waltham MA (United States)

    2012-02-28

    The Cadmus Group, Inc., in collaboration with the National Renewable Energy Laboratory (NREL) and Encraft, was awarded a grant from the Department of Energy (DOE) to develop a site analysis tool for distributed wind technologies. As the principal investigator for this project, Mr. Shawn Shaw was responsible for overall project management, direction, and technical approach. The product resulting from this project is the Distributed Wind Site Analysis Tool (DSAT), a software tool for analyzing proposed sites for distributed wind technology (DWT) systems. This user-friendly tool supports the long-term growth and stability of the DWT market by providing reliable, realistic estimates of site and system energy output and feasibility. DSAT-which is accessible online and requires no purchase or download of software-is available in two account types; Standard: This free account allows the user to analyze a limited number of sites and to produce a system performance report for each; and Professional: For a small annual fee users can analyze an unlimited number of sites, produce system performance reports, and generate other customizable reports containing key information such as visual influence and wind resources. The tool’s interactive maps allow users to create site models that incorporate the obstructions and terrain types present. Users can generate site reports immediately after entering the requisite site information. Ideally, this tool also educates users regarding good site selection and effective evaluation practices.

  13. A model to predict the power output from wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Landberg, L. [Riso National Lab., Roskilde (Denmark)

    1997-12-31

    This paper will describe a model that can predict the power output from wind farms. To give examples of input the model is applied to a wind farm in Texas. The predictions are generated from forecasts from the NGM model of NCEP. These predictions are made valid at individual sites (wind farms) by applying a matrix calculated by the sub-models of WASP (Wind Atlas Application and Analysis Program). The actual wind farm production is calculated using the Riso PARK model. Because of the preliminary nature of the results, they will not be given. However, similar results from Europe will be given.

  14. Benefit Evaluation of Wind Turbine Generators in Wind Farms Using Capacity-Factor Analysis and Economic-Cost Methods

    DEFF Research Database (Denmark)

    Chen, Zhe; Wang, L.; Yeh, T-H.

    2009-01-01

    (PP) of WTGs using Weibull and Rayleigh distribution functions. Five commercial WFs in Taiwan are used as sample systems for comparative analyses. This paper combines Weibull function, cubic mean wind speed, and four existing economic-analysis methods to study different values of capacity and hub...... generators (WTGs). To fully capture wind energy, different wind farms (WFs) should select adequate capacity of WTGs to effectively harvest wind energy and maximize their economic benefit. To establish selection criterion, this paper first derives the equations for capacity factor (CF) and pairing performance...... height for WTGs that have been installed in Taiwan. Important outcomes affecting wind cost of energy in comparison with economic results using the proposed economic-analysis methods for different WFs are also presented....

  15. Analysis of Transient Phenomena Due to a Direct Lightning Strike on a Wind Energy System

    OpenAIRE

    Rafael B. Rodrigues; Victor M. F. Mendes; João P. S. Catalão

    2012-01-01

    This paper is concerned with the protection of wind energy systems against the direct effects of lightning. As wind power generation undergoes rapid growth, lightning damages involving wind turbines have come to be regarded as a serious problem. Nevertheless, very few studies exist yet in Portugal regarding lightning protection of wind energy systems using numerical codes. A new case study is presented in this paper, based on a wind turbine with an interconnecting transformer, for the analysi...

  16. The Run 2 ATLAS Analysis Event Data Model

    CERN Document Server

    SNYDER, S; The ATLAS collaboration; NOWAK, M; EIFERT, T; BUCKLEY, A; ELSING, M; GILLBERG, D; MOYSE, E; KOENEKE, K; KRASZNAHORKAY, A

    2014-01-01

    During the LHC's first Long Shutdown (LS1) ATLAS set out to establish a new analysis model, based on the experience gained during Run 1. A key component of this is a new Event Data Model (EDM), called the xAOD. This format, which is now in production, provides the following features: A separation of the EDM into interface classes that the user code directly interacts with, and data storage classes that hold the payload data. The user sees an Array of Structs (AoS) interface, while the data is stored in a Struct of Arrays (SoA) format in memory, thus making it possible to efficiently auto-vectorise reconstruction code. A simple way of augmenting and reducing the information saved for different data objects. This makes it possible to easily decorate objects with new properties during data analysis, and to remove properties that the analysis does not need. A persistent file format that can be explored directly with ROOT, either with or without loading any additional libraries. This allows fast interactive naviga...

  17. Electromagnetic Analysis of Ring Earth Electrode for Wind Turbine

    Science.gov (United States)

    Fujii, Toshiaki; Yasuda, Yoh; Ueda, Toshiaki

    Lightning protection of wind power generation is becoming an important public issue. Japan in particular suffers from frequent and heavy lightning strikes, such as the notorious “winter lightning” found in coastal areas of the Sea of Japan. Also, it is important to understand the “impedance characteristics” of wind turbine earthing systems from the viewpoint of lightning protection. A report from IEC, TR61400-24, recommends a “ring earth electrode” however, this concept has not been fully clarified, especially its transient behavior during a lightning strike remains unresolved. To confirm the effect of a ring earth electrode, this report presents an electromagnetic transient analysis on a foundation and ring earth electrode of a wind power generator using a Finite Difference Time Domain (FDTD) method. The results show that the ring earth electrode provides a low steady resistance with little inductive potential rise. Thus, it is confirmed that the ring earth electrode provides effective lightning protection of wind turbines.

  18. Wind Turbine Failures - Tackling current Problems in Failure Data Analysis

    Science.gov (United States)

    Reder, M. D.; Gonzalez, E.; Melero, J. J.

    2016-09-01

    The wind industry has been growing significantly over the past decades, resulting in a remarkable increase in installed wind power capacity. Turbine technologies are rapidly evolving in terms of complexity and size, and there is an urgent need for cost effective operation and maintenance (O&M) strategies. Especially unplanned downtime represents one of the main cost drivers of a modern wind farm. Here, reliability and failure prediction models can enable operators to apply preventive O&M strategies rather than corrective actions. In order to develop these models, the failure rates and downtimes of wind turbine (WT) components have to be understood profoundly. This paper is focused on tackling three of the main issues related to WT failure analyses. These are, the non-uniform data treatment, the scarcity of available failure analyses, and the lack of investigation on alternative data sources. For this, a modernised form of an existing WT taxonomy is introduced. Additionally, an extensive analysis of historical failure and downtime data of more than 4300 turbines is presented. Finally, the possibilities to encounter the lack of available failure data by complementing historical databases with Supervisory Control and Data Acquisition (SCADA) alarms are evaluated.

  19. Wind Turbine Gearbox Condition Monitoring Round Robin Study - Vibration Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, S.

    2012-07-01

    The Gearbox Reliability Collaborative (GRC) at the National Wind Technology Center (NWTC) tested two identical gearboxes. One was tested on the NWTCs 2.5 MW dynamometer and the other was field tested in a turbine in a nearby wind plant. In the field, the test gearbox experienced two oil loss events that resulted in damage to its internal bearings and gears. Since the damage was not severe, the test gearbox was removed from the field and retested in the NWTCs dynamometer before it was disassembled. During the dynamometer retest, some vibration data along with testing condition information were collected. These data enabled NREL to launch a Wind Turbine Gearbox Condition Monitoring Round Robin project, as described in this report. The main objective of this project was to evaluate different vibration analysis algorithms used in wind turbine condition monitoring (CM) and find out whether the typical practices are effective. With involvement of both academic researchers and industrial partners, the project sets an example on providing cutting edge research results back to industry.

  20. Vibrational analysis of vertical axis wind turbine blades

    Science.gov (United States)

    Kapucu, Onur

    The goal of this research is to derive a vibration model for a vertical axis wind turbine blade. This model accommodates the affects of varying relative flow angle caused by rotating the blade in the flow field, uses a simple aerodynamic model that assumes constant wind speed and constant rotation rate, and neglects the disturbance of wind due to upstream blade or post. The blade is modeled as elastic Euler-Bernoulli beam under transverse bending and twist deflections. Kinetic and potential energy equations for a rotating blade under deflections are obtained, expressed in terms of assumed modal coordinates and then plugged into Lagrangian equations where the non-conservative forces are the lift and drag forces and moments. An aeroelastic model for lift and drag forces, approximated with third degree polynomials, on the blade are obtained assuming an airfoil under variable angle of attack and airflow magnitudes. A simplified quasi-static airfoil theory is used, in which the lift and drag coefficients are not dependent on the history of the changing angle of attack. Linear terms on the resulting equations of motion will be used to conduct a numerical analysis and simulation, where numeric specifications are modified from the Sandia-17m Darrieus wind turbine by Sandia Laboratories.

  1. Applicability Limits of Operational Modal Analysis to Operational Wind Turbines

    DEFF Research Database (Denmark)

    Tcherniak, D.; Chauhan, Shashank; Hansen, Morten Hartvig

    2011-01-01

    Operational Modal Analysis (OMA) is one of the branches of experimental modal analysis which allows extracting modal parameters based on measuring only the responses of a structure under ambient or operational excitation which is not needed to be measured. This makes OMA extremely attractive...... to modal analysis of big structures such as wind turbines where providing measured excitation force is an extremely difficult task. One of the main OMA assumption concerning the excitation is that it is distributed randomly both temporally and spatially. Obviously, closer the real excitation...

  2. An assessment on seasonal analysis of wind energy characteristics and wind turbine characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Akpinar, E.K.; Akpinar, S. [Firat University, Elazig (Turkey)

    2005-07-01

    This paper presents seasonal variations of the wind characteristics and wind turbine characteristics in the regions around Elazig, namely Maden, Agin and Keban. Mean wind speed data in measured hourly time series format is statistically analyzed for the six year period 1998-2003. The probability density distributions are derived from the time series data and their distributional parameters are identified. Two probability density functions are fitted to the measured probability distributions on a seasonal basis. The wind energy characteristics of all the regions are studied based on the Weibull and Rayleigh distributions. Energy calculations and capacity factors for the wind turbine characteristics were determined for wind machines of different sizes between 300 and 2300 kW. It was found that Maden is the best region, among the regions analyzed, for wind characteristics and wind turbine characteristics. (author)

  3. Analysis and design of a vertical axis wind turbine

    OpenAIRE

    Goyena Iriso, Joseba

    2011-01-01

    The main objective of this project is to design a new vertical axis wind turbine, specifically one Giromill wind turbine. The project development requires performing a previous study of the vertical axis wind turbines currently development. This study has to be performed before starting to design the wind turbine. Other very important aim is the development of a new vertical axis wind turbine. The after analyses that will result in the final design of the wind turbine will b...

  4. CFD Analysis On The Performance Of Wind Turbine With Nozzles

    Directory of Open Access Journals (Sweden)

    Chunkyraj Kh

    2015-08-01

    Full Text Available In this paper an effort has been made in dealing with fluid characteristic that enters a converging nozzle and analysis of the nozzle is carried out using Computational Fluid Dynamics package ANSYS WORKBENCH 14.5. The paper is the continuation of earlier work Analytical and Experimental performance evaluation of Wind turbine with Nozzles. First the CFD analysis will be carried out on nozzle in-front of wind turbine where streamline velocity at the exit volume flow rate in the nozzle and pressure distribution across the nozzle will be studied. Experiments were conducted on the Wind turbine with nozzles and the corresponding power output at different air speed and different size of nozzles were calculated. Different shapes and dimensions with special contours and profiles of nozzles were studied. It was observed that the special contour nozzles have superior outlet velocity and low pressure at nozzle exit the design has maximum Kinetic energy. These indicators conclude that the contraction designed with the new profile is a good enhancing of the nozzle performance.

  5. Technical analysis of photovoltaic/wind systems with hydrogen storage

    Directory of Open Access Journals (Sweden)

    Bakić Vukman V.

    2012-01-01

    Full Text Available The technical analysis of a hybrid wind-photovoltaic energy system with hydrogen gas storage was studied. The market for the distributed power generation based on renewable energy is increasing, particularly for the standalone mini-grid applications. The main design components of PV/Wind hybrid system are the PV panels, the wind turbine and an alkaline electrolyzer with tank. The technical analysis is based on the transient system simulation program TRNSYS 16. The study is realized using the meteorological data for a Typical Metrological Year (TMY for region of Novi Sad, Belgrade cities and Kopaonik national park in Serbia. The purpose of the study is to design a realistic energy system that maximizes the use of renewable energy and minimizes the use of fossil fuels. The reduction in the CO2 emissions is also analyzed in the paper. [Acknowledgment. This paper is the result of the investigations carried out within the scientific project TR33036 supported by the Ministry of Science of the Republic of Serbia.

  6. Cost analysis of DAWT innovative wind energy systems

    Science.gov (United States)

    Foreman, K. M.

    The results of a diffuser augmented wind turbine (DAWT) preliminary design study of three constructional material approaches and cost analysis of DAWT electrical energy generation are presented. Costs are estimated assuming a limited production run (100 to 500 units) of factory-built subassemblies and on-site final assembly and erection within 200 miles of regional production centers. It is concluded that with the DAWT the (busbar) cost of electricity (COE) can range between 2.0 and 3.5 cents/kW-hr for farm and REA cooperative end users, for sites with annual average wind speeds of 16 and 12 mph respectively, and 150 kW rated units. No tax credit incentives are included in these figures. For commercial end users of the same units and site characteristics, the COE ranges between 4.0 and 6.5 cents/kW-hr.

  7. Fatigue Reliability Analysis of Wind Turbine Cast Components

    DEFF Research Database (Denmark)

    Rafsanjani, Hesam Mirzaei; Sørensen, John Dalsgaard; Fæster, Søren

    2017-01-01

    The fatigue life of wind turbine cast components, such as the main shaft in a drivetrain, is generally determined by defects from the casting process. These defects may reduce the fatigue life and they are generally distributed randomly in components. The foundries, cutting facilities and test.......) and to quantify the relevant uncertainties using available fatigue tests. Illustrative results are presented as obtained by statistical analysis of a large set of fatigue data for casted test components typically used for wind turbines. Furthermore, the SN curves (fatigue life curves based on applied stress...... facilities can affect the verification of properties by testing. Hence, it is important to have a tool to identify which foundry, cutting and/or test facility produces components which, based on the relevant uncertainties, have the largest expected fatigue life or, alternatively, have the largest reliability...

  8. A computational analysis of wind turbine and wind farm aerodynamics with a focus on dual rotor wind turbines

    Science.gov (United States)

    Rosenberg, Aaron John

    This dissertation serves to summarize my research into wind farm and wind turbine aerodynamics. Included in this thesis is a summary of the methods I use as well as the four research problems that I investigated. (Abstract shortened by ProQuest.).

  9. Analysis of WWγ production with the ATLAS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Djuvsland, Julia Isabell

    2016-07-28

    In this thesis, triboson final states containing two W bosons and a photon are studied using proton-proton collisions. The data set was recorded with the ATLAS detector at a centre-of-mass energy of √(s)=8 TeV and corresponds to an integrated luminosity of 20.3 fb{sup -1}. The fiducial cross-section of the process WWγ→eνμνγ is measured for the first time in hadron collisions and corresponds to σ{sup eμγ}{sub fid.}=(1.89±0.93(stat.)±0.41(syst.)±0.05(lumi. )) fb. It is in good agreement with the Standard Model prediction at next-to-leading order in the strong coupling constant. As no deviation from the Standard Model expectation is observed, frequentist limits at 95 % confidence level are computed to exclude contributions from anomalous quartic gauge couplings. This analysis is sensitive to fourteen coupling parameters of mass dimension eight and the limits are derived for all parameters with and without unitarisation.

  10. Analysis of Offshore Wind Energy Leasing Areas for the Rhode Island/Massachusetts Wind Energy Area

    Energy Technology Data Exchange (ETDEWEB)

    Musial, W.; Elliott, D.; Fields, J.; Parker, Z.; Scott, G.

    2013-04-01

    The National Renewable Energy Laboratory (NREL), under an interagency agreement with the Bureau of Ocean Energy Management (BOEM), is providing technical assistance to BOEM on the identification and delineation of offshore leasing areas for offshore wind energy development within the Atlantic Coast Wind Energy Areas (WEAs) established by BOEM in 2012. This report focuses on NREL's evaluation of BOEM's Rhode Island/Massachusetts (RIMA) WEA leasing areas. The objective of the NREL evaluation was to assess the proposed delineation of the two leasing areas and determine if the division is reasonable and technically sound. Additionally, the evaluation aimed to identify any deficiencies in the delineation. As part of the review, NREL performed the following tasks: 1. Performed a limited review of relevant literature and RIMA call nominations. 2. Executed a quantitative analysis and comparison of the two proposed leasing areas 3. Conducted interviews with University of Rhode Island (URI) staff involved with the URI Special Area Management Plan (SAMP) 4. Prepared this draft report summarizing the key findings.

  11. A Comparative Analysis of Community Wind Power DevelopmentModels

    Energy Technology Data Exchange (ETDEWEB)

    Bolinger, Mark; Wiser, Ryan; Wind, Tom; Juhl, Dan; Grace, Robert; West, Peter

    2005-05-20

    For years, farmers in the United States have looked with envy on their European counterparts ability to profitably farm the wind through ownership of distributed, utility-scale wind projects. Only within the past few years, however, has farmer- or community-owned windpower development become a reality in the United States. The primary hurdle to this type of development in the United States has been devising and implementing suitable business and legal structures that enable such projects to take advantage of tax-based federal incentives for windpower. This article discusses the limitations of such incentives in supporting farmer- or community-owned wind projects, describes four ownership structures that potentially overcome such limitations, and finally conducts comparative financial analysis on those four structures, using as an example a hypothetical 1.5 MW farmer-owned project located in the state of Oregon. We find that material differences in the competitiveness of each structure do exist, but that choosing the best structure for a given project will largely depend on the conditions at hand; e.g., the ability of the farmer(s) to utilize tax credits, preference for individual versus cooperative ownership, and the state and utility service territory in which the project will be located.

  12. Failure analysis of collector circuits associated with wind farms

    Directory of Open Access Journals (Sweden)

    Clifton Ashley P.

    2017-01-01

    Full Text Available Wind farm collector circuits generally comprise several wind turbine generators (WTG’s. WTG’s are connected in parallel to a substation. This connection acts as the point-of-connection to the national electricity grid. The electrical load in these circuits is close to component (power cables and accessories ratings. The objective of this paper is to identify cable joint failure paths; and, develop an understanding of specific contributing factors. All findings presented were established from literature review involving data analysis and discussion with industry experts working across the wind industry. Application of forces, inadequate workmanship, incorrect thermal resistance or other contributing factors, all contribute to high conductor operating temperatures. High conductor operating temperatures highlight issues including insufficient environmental heat transfer due to the use of inadequate cable trenching materials. This in turn results in the imbalanced application of force, experienced at the cable joint, as a direct result of frequent thermal expansion and contraction. For most cable joint failures, the root cause is insulation breakdown due to sustained deterioration of the cross-linked polyethylene insulation. This is a direct result from excessive operating temperatures.

  13. Roadmap to the multidisciplinary design analysis and optimisation of wind energy systems

    DEFF Research Database (Denmark)

    Sanchez Perez-Moreno, S.; Zaaijer, M. B.; Bottasso, C. L.

    2016-01-01

    architecture. It is foreseen that sensible answers to all these questions will enable to more easily apply MDAO in the wind energy domain. Beyond the agenda, this work also promotes the use of systems engineering to design, analyse and optimise wind turbines and wind farms, to complement existing......A research agenda is described to further encourage the application of Multidisciplinary Design Analysis and Optimisation (MDAO) methodologies to wind energy systems. As a group of researchers closely collaborating within the International Energy Agency (IEA) Wind Task 37 for Wind Energy Systems...

  14. Second NASA Technical Interchange Meeting (TIM): Advanced Technology Lifecycle Analysis System (ATLAS) Technology Tool Box (TTB)

    Science.gov (United States)

    ONeil, D. A.; Mankins, J. C.; Christensen, C. B.; Gresham, E. C.

    2005-01-01

    The Advanced Technology Lifecycle Analysis System (ATLAS), a spreadsheet analysis tool suite, applies parametric equations for sizing and lifecycle cost estimation. Performance, operation, and programmatic data used by the equations come from a Technology Tool Box (TTB) database. In this second TTB Technical Interchange Meeting (TIM), technologists, system model developers, and architecture analysts discussed methods for modeling technology decisions in spreadsheet models, identified specific technology parameters, and defined detailed development requirements. This Conference Publication captures the consensus of the discussions and provides narrative explanations of the tool suite, the database, and applications of ATLAS within NASA s changing environment.

  15. Reliability Engineering Analysis of ATLAS Data Reprocessing Campaigns

    CERN Document Server

    Vaniachine, A; The ATLAS collaboration; Karpenko, D

    2013-01-01

    During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability...

  16. Reliability Engineering Analysis of ATLAS Data Reprocessing Campaigns

    CERN Document Server

    Vaniachine, A; The ATLAS collaboration; Karpenko, D

    2014-01-01

    During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability...

  17. Roadmap to the multidisciplinary design analysis and optimisation of wind energy systems

    NARCIS (Netherlands)

    Sanchez Perez Moreno, S.; Zaayer, M.B.; Bottasso, C.L.; Dykes, K; Merz, K.O.; Rethore, P.E.

    2016-01-01

    A research agenda is described to further encourage the application of Multidisciplinary Design Analysis and Optimisation (MDAO) methodologies to wind energy systems. As a group of researchers closely collaborating within the International Energy Agency (IEA) Wind Task 37 for Wind Energy Systems

  18. Probabilistic analysis of mean-response along-wind induced vibrations on wind turbine towers using wireless network data sensors

    Science.gov (United States)

    Velazquez, Antonio; Swartz, Raymond A.

    2011-04-01

    Wind turbine systems are attracting considerable attention due to concerns regarding global energy consumption as well as sustainability. Advances in wind turbine technology promote the tendency to improve efficiency in the structure that support and produce this renewable power source, tending toward more slender and larger towers, larger gear boxes, and larger, lighter blades. The structural design optimization process must account for uncertainties and nonlinear effects (such as wind-induced vibrations, unmeasured disturbances, and material and geometric variabilities). In this study, a probabilistic monitoring approach is developed that measures the response of the turbine tower to stochastic loading, estimates peak demand, and structural resistance (in terms of serviceability). The proposed monitoring system can provide a real-time estimate of the probability of exceedance of design serviceability conditions based on data collected in-situ. Special attention is paid to wind and aerodynamic characteristics that are intrinsically present (although sometimes neglected in health monitoring analysis) and derived from observations or experiments. In particular, little attention has been devoted to buffeting, usually non-catastrophic but directly impacting the serviceability of the operating wind turbine. As a result, modal-based analysis methods for the study and derivation of flutter instability, and buffeting response, have been successfully applied to the assessment of the susceptibility of high-rise slender structures, including wind turbine towers. A detailed finite element model has been developed to generate data (calibrated to published experimental and analytical results). Risk assessment is performed for the effects of along wind forces in a framework of quantitative risk analysis. Both structural resistance and wind load demands were considered probabilistic with the latter assessed by dynamic analyses.

  19. Atlas-Based Ventricular Shape Analysis for Understanding Congenital Heart Disease.

    Science.gov (United States)

    Farrar, Genevieve; Suinesiaputra, Avan; Gilbert, Kathleen; Perry, James C; Hegde, Sanjeet; Marsden, Alison; Young, Alistair A; Omens, Jeffrey H; McCulloch, Andrew D

    2016-12-01

    Congenital heart disease is associated with abnormal ventricular shape that can affect wall mechanics and may be predictive of long-term adverse outcomes. Atlas-based parametric shape analysis was used to analyze ventricular geometries of eight adolescent or adult single-ventricle CHD patients with tricuspid atresia and Fontans. These patients were compared with an "atlas" of non-congenital asymptomatic volunteers, resulting in a set of z-scores which quantify deviations from the control population distribution on a patient-by-patient basis. We examined the potential of these scores to: (1) quantify abnormalities of ventricular geometry in single ventricle physiologies relative to the normal population; (2) comprehensively quantify wall motion in CHD patients; and (3) identify possible relationships between ventricular shape and wall motion that may reflect underlying functional defects or remodeling in CHD patients. CHD ventricular geometries at end-diastole and end-systole were individually compared with statistical shape properties of an asymptomatic population from the Cardiac Atlas Project. Shape analysis-derived model properties, and myocardial wall motions between end-diastole and end-systole, were compared with physician observations of clinical functional parameters. Relationships between altered shape and altered function were evaluated via correlations between atlas-based shape and wall motion scores. Atlas-based shape analysis identified a diverse set of specific quantifiable abnormalities in ventricular geometry or myocardial wall motion in all subjects. Moreover, this initial cohort displayed significant relationships between specific shape abnormalities such as increased ventricular sphericity and functional defects in myocardial deformation, such as decreased long-axis wall motion. These findings suggest that atlas-based ventricular shape analysis may be a useful new tool in the management of patients with CHD who are at risk of impaired ventricular

  20. Twistact techno-economic analysis for wind turbine applications.

    Energy Technology Data Exchange (ETDEWEB)

    Naughton, Brian Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Koplow, Jeffrey P. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Vanness, Justin William [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Sethuraman, Latha [National Renewable Energy Lab. (NREL), Golden, CO (United States); Maness, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dykes, Katherine [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-09-01

    This report is the final deliverable for a techno-economic analysis of the Sandia National Laboratories-developed Twistact rotary electrical conductor. The U.S. Department of Energy Wind Energy Technologies Office supported a team of researchers at Sandia National Laboratories and the National Renewable Energy Laboratory to evaluate the potential of the Twistact technology to serve as a viable replacement to rare-earth materials used in permanent-magnet direct-drive wind turbine generators. This report compares three detailed generator models, two as baseline technologies and a third incorporating the Twistact technology. These models are then used to calculate the levelized cost of energy (LCOE) for three comparable offshore wind plants using the three generator topologies. The National Renewable Energy Laboratorys techno-economic analysis indicates that Twistact technology can be used to design low-maintenance, brush-free, and wire-wound (instead of rare-earth-element (REE) permanent-magnet), direct-drive wind turbine generators without a significant change in LCOE and generation efficiency. Twistact technology acts as a hedge against sources of uncertain costs for direct-drive generators. On the one hand, for permanent-magnet direct-drive (PMDD) generators, the long-term price of REEs may increase due to increases in future demand, from electric vehicles and other technologies, whereas the supply remains limited and geographically concentrated. The potential higher prices in the future adversely affect the cost competitiveness of PMDD generators and may thwart industry investment in the development of the technology for wind turbine applications. Twistact technology can eliminate industry risk around the uncertainty of REE price and availability. Traditional wire-wound direct-drive generators experience reliability issues and higher maintenance costs because of the wear on the contact brushes necessary for field excitation. The brushes experience

  1. Fully vs. Sequentially Coupled Loads Analysis of Offshore Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Damiani, Rick; Wendt, Fabian; Musial, Walter; Finucane, Z.; Hulliger, L.; Chilka, S.; Dolan, D.; Cushing, J.; O' Connell, D.; Falk, S.

    2017-06-19

    The design and analysis methods for offshore wind turbines must consider the aerodynamic and hydrodynamic loads and response of the entire system (turbine, tower, substructure, and foundation) coupled to the turbine control system dynamics. Whereas a fully coupled (turbine and support structure) modeling approach is more rigorous, intellectual property concerns can preclude this approach. In fact, turbine control system algorithms and turbine properties are strictly guarded and often not shared. In many cases, a partially coupled analysis using separate tools and an exchange of reduced sets of data via sequential coupling may be necessary. In the sequentially coupled approach, the turbine and substructure designers will independently determine and exchange an abridged model of their respective subsystems to be used in their partners' dynamic simulations. Although the ability to achieve design optimization is sacrificed to some degree with a sequentially coupled analysis method, the central question here is whether this approach can deliver the required safety and how the differences in the results from the fully coupled method could affect the design. This work summarizes the scope and preliminary results of a study conducted for the Bureau of Safety and Environmental Enforcement aimed at quantifying differences between these approaches through aero-hydro-servo-elastic simulations of two offshore wind turbines on a monopile and jacket substructure.

  2. A statistical analysis of wind speed data used in installation of wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Kavak Akpinar, E. [Firat University, Elazig (Turkey). Mechanical Engineering Dept.; Akpinar, S. [Firat University, Elazig (Turkey). Physics Dept.

    2005-03-01

    Wind speed is the most important parameter in the design and study of wind energy conversion systems. In this study, statistical methods were used to analyze the wind speed data of Keban-Elazig in the east region of Turkey. Measured hourly time series of wind speed data were obtained from the State Meteorological Station in Keban-Elazig over a five-year period from 1998 to 2002. The probability density distributions are derived from the time series data and the distributional parameters are identified. Two probability density functions are fitted to the measured probability distributions on a yearly basis. (author)

  3. Analysis of Anholt offshore wind farm SCADA measurements

    DEFF Research Database (Denmark)

    Hansen, Kurt Schaldemose; Volker, Patrick; Pena Diaz, Alfredo

    SCADA measurements from the Danish Anholt offshore wind farm (ANH) for a period of 2½ years have been qualified. ANH covers 12 km × 22 km and is located between Djursland and the island Anholt in Kattegat, Denmark. This qualification encompasses identification of curtailment and idling periods......, start/stop events and a power curve control for each wind turbine in the wind farm. Data also include wind speed measurements from a nearby WindCube lidar and simulations from the WRF model for the same period as the SCADA. An equivalent wind speed (wsi) is derived from the combined power and pitch...

  4. KEGG Atlas mapping for global analysis of metabolic pathways

    Science.gov (United States)

    Okuda, Shujiro; Yamada, Takuji; Hamajima, Masami; Itoh, Masumi; Katayama, Toshiaki; Bork, Peer; Goto, Susumu; Kanehisa, Minoru

    2008-01-01

    KEGG Atlas is a new graphical interface to the KEGG suite of databases, especially to the systems information in the PATHWAY and BRITE databases. It currently consists of a single global map and an associated viewer for metabolism, covering about 120 KEGG metabolic pathway maps and about 10 BRITE hierarchies. The viewer allows the user to navigate and zoom the global map under the Ajax technology. The mapping of high-throughput experimental data onto the global map is the main use of KEGG Atlas. In the global metabolism map, the node (circle) is a chemical compound and the edge (line) is a set of reactions linked to a set of KEGG Orthology (KO) entries for enzyme genes. Once gene identifiers in different organisms are converted to the K number identifiers in the KO system, corresponding line segments can be highlighted in the global map, allowing the user to view genome sequence data as organism-specific pathways, gene expression data as up- or down-regulated pathways, etc. Once chemical compounds are converted to the C number identifiers in KEGG, metabolomics data can also be displayed in the global map. KEGG Atlas is available at http://www.genome.jp/kegg/atlas/. PMID:18477636

  5. Study of Jet Substructure in the ATLAS Experiment using Distributed Analysis within Spanish Tier-2 Infrastuctures

    OpenAIRE

    Oliver García, Elena

    2013-01-01

    Study of Jet Substructure in the ATLAS experiment using Distributed Analysis within Spanish Tier-2 Infrastructures (Estudio de Subestructura de Jets en el experimento ATLAS usando Análisis Distribuido dentro de las Infraestructuras del Tier-2 Español) Resumen en español 1. Motivación En el Large Hadron Collider (LHC) se producen partículas consideradas objetos ‘boosted’ donde sus productos de desintegración se concentran en una pequeña parte del detector. El estudio de estos ...

  6. NASA Technical Interchange Meeting (TIM): Advanced Technology Lifecycle Analysis System (ATLAS) Technology Tool Box

    Science.gov (United States)

    ONeil, D. A.; Craig, D. A.; Christensen, C. B.; Gresham, E. C.

    2005-01-01

    The objective of this Technical Interchange Meeting was to increase the quantity and quality of technical, cost, and programmatic data used to model the impact of investing in different technologies. The focus of this meeting was the Technology Tool Box (TTB), a database of performance, operations, and programmatic parameters provided by technologists and used by systems engineers. The TTB is the data repository used by a system of models known as the Advanced Technology Lifecycle Analysis System (ATLAS). This report describes the result of the November meeting, and also provides background information on ATLAS and the TTB.

  7. Analysis of extreme wind events at Høvsøre and the effect on wind turbine loads

    DEFF Research Database (Denmark)

    Hannesdóttir, Ásta; Kelly, Mark C.; Mann, Jakob

    of this analysis is to answer the questions: 1. How are the wind-turbine loads affected by these events? 2. What atmospheric parameters give rise to the highest loads? The data used for the analysis is from a 160 m tall lighting tower in Høvsøre, which is a measurement site approximately 2 km from the west coast...

  8. The Wind Energy Potential of Iceland

    Science.gov (United States)

    Nawri, Nikolai; Nína Petersen, Guðrún; Bjornsson, Halldór; Hahmann, Andrea N.; Jónasson, Kristján; Bay Hasager, Charlotte; Clausen, Niels-Erik

    2014-05-01

    infrastructure and the power grid, as well as due to the harsh winter climate. However, even in easily accessible regions, wind energy potential in Iceland, as measured by annual average power density, is among the highest in Western Europe. Based on these results, 14 test sites were selected for more detailed analyses using the Wind Atlas Analysis and Application Program (WAsP). These calculations show that a modest wind farm of ten medium size turbines would produce more energy throughout the year than a small hydro power plant, making wind energy a viable additional option.

  9. Fully Coupled Dynamic Analysis of a Floating Wind Turbine System

    National Research Council Canada - National Science Library

    Withee, Jon

    2004-01-01

    ... have been developed and are being proposed for operation in offshore areas where environmental restrictions are less restrictive, large wind resources exist, and open sea areas are available for wind farm development...

  10. A survey of ponticulus posticus: Radiological analysis of atlas in an ...

    African Journals Online (AJOL)

    2015-08-06

    Aug 6, 2015 ... A survey of ponticulus posticus: Radiological analysis of atlas in an orthodontic population based on cone-beam computed tomography. SK Buyuk, AE Sekerci1, YA Benkli, A Ekizer2. Department of Orthodontics, Faculty of Dentistry, Ordu University, 52100 Ordu, Departments of 1Maxillofacial Radiology.

  11. GOODBYE TO PAPER, HIGHLIGHTERS, SCISSORS AND GLUE: INNOVATING THE CONTENT ANALYSIS PROCESS THROUGH ATLAS.TI

    Directory of Open Access Journals (Sweden)

    Silvana Anita Walter

    2015-06-01

    Full Text Available Atlas.ti software comprises a tool for the analysis of qualitative data that can facilitate its management and interpretation. However, the use of this software has been much less frequent in strategy, despite the increasing use of content analysis in this area.This study aimed to demonstrate, through an example, the applicability of Atlas.ti software in conducting thematic content analysis in the strategy area. The example used was a survey conducted on two accounting firms in Curitiba, Paraná (PR, and applied to the firm’s directors, as a data collection instrument, through semi-structured interviews. With the help of Atlas.ti 5.0 software, thematic content analysis was undertaken and brought to light that the two offices have a similar trajectory; they are characterized as family members; they hold or held centralization of power; made innovations; do not have formalized plans; and, most of their strategies are emerging. The example used allowed for the demonstration of: the encoding process; the writing of research notes and comments; the establishment of relationships between the elements analyzed; and, the grouping and management of such elements. It is hoped that this study contributes to stimulating the use of Atlas.ti software and assists in improving the consistency and betterment of qualitative research through the ease of empirical verification.

  12. Automated analysis of small animal PET studies through deformable registration to an atlas

    NARCIS (Netherlands)

    Gutierrez, Daniel F.; Zaidi, Habib

    2012-01-01

    This work aims to develop a methodology for automated atlas-guided analysis of small animal positron emission tomography (PET) data through deformable registration to an anatomical mouse model. A non-rigid registration technique is used to put into correspondence relevant anatomical regions of

  13. Assessment and analysis of wind energy generation and power ...

    African Journals Online (AJOL)

    This study concerns the evaluation of wind power potential and the choice of a wind turbine to be installed near Rabah Bitat international airport of Annaba. Furthermore, the performances of power control of this turbine are developed. For this, the wind speed data measured by meteorological station of th e airport are used.

  14. Simulation analysis of a wind farm with different aggregated models

    DEFF Research Database (Denmark)

    Li, H.; Wang, H.; Zhao, B.

    2011-01-01

    Based on a wind farm including wind turbines with squirrel cage induction generators (SCIGs), different aggregated models of a wind farm, such as a single weighted average model, a reduced-order re-scaled model, a parameter transformed model and a single weighted arithmetic model were presented, ...

  15. Offshore Wind Energy Analysis of Cyclone Xaver over North Europe

    NARCIS (Netherlands)

    Christakos, Konstantinos; Cheliotis, Ioannis; Varlas, George; Steeneveld, G.J.

    2016-01-01

    Cyclone Xaver (5 December 2013; North Sea) was an extreme weather event which affected northern Europe, yielding a record of wind power generation. The most striking aspects of this atmospheric phenomenon were the gale-force winds and the upcoming abrupt increase of the wind power over the North

  16. Integrating Wind Power in Electricity Grids : an Economic Analysis

    NARCIS (Netherlands)

    Liu, J.; Kooten, van G.C.; Pitt, L.

    2005-01-01

    As a renewable energy source, wind power is gaining popularity as a favoured alternative to fossil fuel, nuclear and hydro power generation. In Europe, countries are required to achieve 15% of their energy consumption from wind by 2010 as the EU strives to meet its Kyoto obligations. Wind power is

  17. Spectral analysis of wind field in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Rashmi, R.; Samiksha, S.V.; Polnikov, V.; Pogarskii, F.; Sudheesh, K.; Vethamony, P.

    To study the variability in wind fields over the Indian Ocean, we used ERA INTERIM daily winds for the period 1979-2012 In order to analyse the temporal variation of wind field, we partitioned the whole Indian Ocean into 6 zones based on spatial...

  18. Implementation of spectrum analysis in mesoscale modeling for wind energy assessment studies

    DEFF Research Database (Denmark)

    Stathopoulos, C.; Barranger, N.; Larsén, Xiaoli Guo

    2012-01-01

    Spectral analysis of wind speed is a key parameter for the characterization of the physical processes generating the fields. Especially, the mesoscale power spectrum is an important measure of accuracy of wind forecasting and extreme wind estimation for modern wind farms, which are of the size...... response to this deviation at different scales. Using simulation of the Iberian Peninsula and data experiments, we first identify the difference in wind kinetic energy spectrum between a hilly region in Spain and an offshore domain nearby the Portuguese coast. A powerful tool to determine the interaction...... between complex terrain and the wind variability is the use of 2D Fast Fourier transform applied to terrain height. From previous studies this analysis proved to be efficient in finding the proper model grid resolution for the representation of the wind variability in highly non homogeneous terrain...

  19. Analysis of the potential for hydrogen production in the province of Cordoba, Argentina, from wind resources

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, C.R.; Santa Cruz, R.; Aisa, S. [Universidad Empresarial Siglo 21, Monsenor Pablo Cabrera s/n calle, 5000 Cordoba (Argentina); Riso, M.; Jimenez Yob, G.; Ottogalli, R. [Subsecretaria de Infraestructuras y Programas, Ministerio de Obras y Servicios Publicos del Gobierno de la Provincia de Cordoba, Av. Poeta Lugones 12, 2do. Piso, 5000 Cordoba (Argentina); Jeandrevin, G. [Instituto Universitario Aeronautico, Avenida Fuerza Aerea km 6 1/2, 5022 Cordoba (Argentina); Leiva, E.P.M. [INFIQC, Unidad de Matematica y Fisica, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, Haya de la Torre s/n, 5010 Cordoba (Argentina)

    2010-06-15

    The potential for hydrogen production from wind resources in the province of Cordoba, second consumer of fossil fuels for transportation in Argentina, is analyzed. Three aspects of the problem are considered: the evaluation of the hydrogen resource from wind power, the analysis of the production costs via electrolysis and the annual requirements of wind energy to generate hydrogen to fuel the vehicular transport of the province. Different scenarios were considered, including pure hydrogen as well as the so-called CNG plus, where hydrogen is mixed with compressed natural gas in a 20% V/V dilution of the former. The potential for hydrogen production from wind resources is analyzed for each department of the province, excluding those regions not suited for wind farms. The analysis takes into account the efficiency of the electrolyzer and the capacity factor of the wind power system. It is concluded that the automotive transportation could be supplied by hydrogen stemming from wind resources via electrolysis. (author)

  20. Time domain analysis method for aerodynamic noises from wind turbine blades

    Directory of Open Access Journals (Sweden)

    Hua ZHAO

    2015-04-01

    Full Text Available The issue of the aerodynamic noises from wind turbine blades affecting the surrounding residents life begins to attract researcher's attention. Most of the existing researches are based on CFD software or experimental data fitting method to analyze the aerodynamic noises, so it is difficult to adapt the demand to dynamic analysis of the aerodynamic noises from wind speed variation. In this paper, the operation parameters, the inflow wind speed and the receiver location are considered, and a modified model to calculate aerodynamic noises from wind turbine blades which is based on traditional acoustic formulas is established. The program to calculate the aerodynamic noises from the 2 MW wind turbine blades is compiled using a time-domain analysis method based on the Simulink modular in Matlab software. And the pressure time sequence diagrams of the aerodynamic noises from wind turbine blades are drawn. It has provided a theoretical foundation to develop low noise wind turbine blades.

  1. Bimodal versus Weibull wind speed distributions: an analysis of wind energy potential in La Venta, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Jaramillo, O.A.; Borja, M.A.

    2004-07-01

    The International Standard IEC 61400-12 and other international recommendations suggest the use of the two-parameter Weibull probability distribution function (PDF) to estimate the Annual Energy Production (AEP) of a wind turbine. Most of the commercial software uses the unimodal Weibull PDF as the default option to carry out estimations of AEP, which in turn, are used to optimise wind farm layouts. Furthermore, AEP is essential data to assess the economic feasibility of a wind power project. However, in some regions of the world, the use of these widely adopted and recommended methods lead to incorrect results. This is the case for the region of La Ventosa in Mexico, where the frequency of the wind speed shows a bimodal distribution. In this work, mathematical formulations by using a Weibull PDF and a bimodal distribution are established to compare the AEP, the capacity factor and the levelised production cost for a specific wind turbine. By combining one year of wind speed data with the hypothetic power performance of the Vestas V27-225 kW wind turbine, it was found that using the Weibull PDF underestimates AEP (and thus the Capacity Factor) by about 12%. (author)

  2. Generation of an Atlas of the Proximal Femur and Its Application to Trabecular Bone Analysis

    Science.gov (United States)

    Carballido-Gamio, Julio; Folkesson, Jenny; Karampinos, Dimitrios C.; Baum, Thomas; Link, Thomas M.; Majumdar, Sharmila; Krug, Roland

    2013-01-01

    Automatic placement of anatomically corresponding volumes of interest and comparison of parameters against a standard of reference are essential components in studies of trabecular bone. Only recently, in vivo MR images of the proximal femur, an important fracture site, could be acquired with high-spatial resolution. The purpose of this MRI trabecular bone study was two-fold: (1) to generate an atlas of the proximal femur to automatically place anatomically corresponding volumes of interest in a population study and (2) to demonstrate how mean models of geodesic topological analysis parameters can be generated to be used as potential standard of reference. Ten females were used to generate the atlas and geodesic topological analysis models, and 10 females were used to demonstrate the atlas-based trabecular bone analysis. All alignments were based on three-dimensional (3D) multiresolution affine transformations followed by 3D multiresolution free-form deformations. Mean distances less than 1 mm between aligned femora, and sharp edges in the atlas and in fused gray-level images of registered femora indicated that the anatomical variability was well accommodated and explained by the free-form deformations. PMID:21432904

  3. Performance Analysis of NACA2420 as Wind Turbine Propeller Blade

    Directory of Open Access Journals (Sweden)

    Sulaeman Mustafa

    2017-03-01

    Full Text Available Wind is one of the popular renewable energy sources which is abundantly available either in land or at sea. The wind energy can be converted into electrical energy using wind turbines or wind energy conversion systems. However, the exploration and utilization of wind energy potential in Indonesia is not optimal yet. Therefore, in the present study, the performance of a NACA2420 airfoil as wind turbine blade is evaluated. The main objective of the present research is to determine the optimum angle of the propeller blade that can deliver the most optimum performance. In order to achieve the objectives, the wind turbine blade model was tested using a wind tunnel at wind speeds varying from 2 to 9 m/s. From this research, it is demonstrated that the tunnel has helped to increase the wind speed. The maximum wind speed was generated from the tunnel when the fan distance was 1.1 m. In addition, the experiment was also carried out by varying the pitch angles to be 00, 50, 80, 150, and 300. From the test measurements, it was found that the pitch angle of 50 produces the most optimal power which was at 221.039 watts with 0.401 of power coefficient.

  4. Multivariate multifractal detrended fluctuation analysis of 3D wind field signals

    Science.gov (United States)

    Zhang, Xiaonei; Zeng, Ming; Meng, Qinghao

    2018-01-01

    Characterizing the dynamic behavior underlying wind field from experimental multivariate signals is a challenging problem of continuous interest. In this work, we propose the multivariate multifractal detrended fluctuation analysis (MV-MFDFA) method to directly study the fractal dynamics of multichannel data in a complex system. By conducting several simulations on synthetic multivariate series, the validity of the proposed MV-MFDFA is illustrated. Then we utilize MV-MFDFA to analyze the 3D wind field signals collected at two different airflow environments, i.e., indoor and outdoor environments. Results show that the indoor and outdoor three wind vectors show multifractal properties, and the multifractal degrees of outdoor three wind vectors are stronger than those of corresponding indoor three wind vectors. By analyzing the indoor and outdoor multivariate wind speed, we find that the indoor and outdoor multivariate wind speed are antipersistent long-range correlation, and the indoor multivariate wind speed exhibits weaker multifractal properties than that of outdoor multivariate wind speed. Moreover, the multifractality of indoor multivariate wind speed depends mainly on the large fluctuations, while the multifractality of outdoor multivariate wind speed depends mainly on the small fluctuations. These findings indicate that the MV-MFDFA allows better understanding the dynamical mechanisms governing 3D wind variability.

  5. A Comparison of Wind Flow Models for Wind Resource Assessment in Wind Energy Applications

    Directory of Open Access Journals (Sweden)

    Mathieu Landry

    2012-10-01

    Full Text Available The objective of this work was to assess the accuracy of various coupled mesoscale-microscale wind flow modeling methodologies for wind energy applications. This is achieved by examining and comparing mean wind speeds from several wind flow modeling methodologies with observational measurements from several 50 m met towers distributed across the study area. At the mesoscale level, with a 5 km resolution, two scenarios are examined based on the Mesoscale Compressible Community Model (MC2 model: the Canadian Wind Energy Atlas (CWEA scenario, which is based on standard input data, and the CWEA High Definition (CWEAHD scenario where high resolution land cover input data is used. A downscaling of the obtained mesoscale wind climate to the microscale level is then performed, where two linear microscale models, i.e., MsMicro and the Wind Atlas Analysis and Application Program (WAsP, are evaluated following three downscaling scenarios: CWEA-WAsP, CWEA-MsMicro and CWEAHD-MsMicro. Results show that, for the territory studied, with a modeling approach based on the MC2 and MsMicro models, also known as Wind Energy Simulation Toolkit (WEST, the use of high resolution land cover and topography data at the mesoscale level helps reduce modeling errors for both the mesoscale and microscale models, albeit only marginally. At the microscale level, results show that the MC2-WAsP modeling approach gave substantially better results than both MC2 and MsMicro modeling approaches due to tweaked meso-micro coupling.

  6. The Modeling and Simulation of Thermal Analysis at Hydro Generator Stator Winding Insulation

    Directory of Open Access Journals (Sweden)

    Mihaela Raduca

    2006-10-01

    Full Text Available This paper presents the modelling and simulation of thermal analysis at hydro generator stator winding. The winding stator is supplied at high voltage of 11 kV for high power hydro generator. To present the thermal analysis for stator winding is presented at supply of coil by 11 kV, when coil is heat and thermal transfer in insulation at ambient temperature.

  7. A method for data base management and analysis for wind tunnel data

    Science.gov (United States)

    Biser, Aileen O.

    1987-01-01

    To respond to the need for improved data base management and analysis capabilities for wind-tunnel data at the Langley 16-Foot Transonic Tunnel, research was conducted into current methods of managing wind-tunnel data and a method was developed as a solution to this need. This paper describes the development of the data base management and analysis method for wind-tunnel data. The design and implementation of the software system are discussed and examples of its use are shown.

  8. Danish wind power in Brazil. Part 1. The future of wind power in Brazil - market analysis

    Energy Technology Data Exchange (ETDEWEB)

    Husted Rich, N.

    1996-04-01

    More than 95% of total energy produced in Brazil comes from highly efficient hydroelectric power plants but, faced with a serious shortage of energy after the year 2000, the country is now considering wind energy as one of the basic alternatives for energy supply. It is suggested that biomass, wind energy and biogas may be included in a future supply policy for the north-east region of the land. The structure of, the privatisation, legislation and the tariff system within the Brazilian power sector are described in addition to the present situation regarding wind energy in the country, including current and coming projects in this field, the excellent wind conditions in Northeastern Brazil and investment possibilities. The political activities in this field of the Danish Folkecenter for Renewable Energy are noted and future developments in Brazil are discussed. It is concluded that there are good prospects for Danish windmill technology on the Brazilian market. Wind measurement programs are presently being carried out in various areas of the country, though a number of impediments to the development of wind energy in Brazil remain. (AB)

  9. Distributed analysis functional testing using GangaRobot in the ATLAS experiment

    CERN Document Server

    Legger, F; The ATLAS collaboration; Elmsheuser, J; Ubeda García, M; Gordon, A W; Jha, M K; Van der Ster, D C

    2010-01-01

    Automated distributed analysis tests are necessary to ensure smooth operations of the ATLAS grid resources. In this work we present the recent developments of the ATLAS GangaRobot, a tool designed to perform regular tests of all grid sites by running arbitrary user applications with varied configurations at predifined time intervals. Specifically the GangaRobot creates and submits several real ATLAS user applications to the various grid sites using the distributed analysis framework GANGA, a front end for easy grid job definition and management. Success or failure rates of these test jobs are individually monitored. Test definitions and results are stored in a database and made available to users and site administrators through a web interface, the ATLAS Site Status Board (SSB) and the Service Availability Monitor (SAM). The test results provide on the one hand a fast way to to identify systematic or temporary site problems, and on the other hand allow for an effective distribution of the workload on the avai...

  10. Harmonic Analysis and Active Filtering in Offshore Wind Power Plants

    DEFF Research Database (Denmark)

    Chaudhary, Sanjay Kumar; Freijedo Fernandez, Francisco Daniel; Guerrero, Josep M.

    2015-01-01

    at the point of common coupling (PCC). The resonance conditions should be avoided in all cases. This paper describes the harmonic analysis techniques applied on an OWPP network model. A method is proposed to estimate the harmonic current compensation from a shunt-connected active power filter to mitigate......Due to presence of long high voltage cable networks, and power transformers for the grid connection, the offshore wind power plants (OWPPs) are susceptible to harmonic distortion and resonances. The grid connection of OWPP should not cause the harmonic distortion beyond the permissible limits...... the harmonic voltage distortion at the PCC. Finally the harmonic distortions in the compensated and the uncompensated systems are compared to demonstrate the efficacy of the compensation....

  11. Analysis methods for wind turbine control and electrical system dynamics

    Science.gov (United States)

    Hinrichsen, E. N.

    1995-01-01

    The integration of new energy technologies into electric power systems requires methods which recognize the full range of dynamic events in both the new generating unit and the power system. Since new energy technologies are initially perceived as small contributors to large systems, little attention is generally paid to system integration, i.e. dynamic events in the power system are ignored. As a result, most new energy sources are only capable of base-load operation, i.e. they have no load following or cycling capability. Wind turbines are no exception. Greater awareness of this implicit (and often unnecessary) limitation is needed. Analysis methods are recommended which include very low penetration (infinite bus) as well as very high penetration (stand-alone) scenarios.

  12. Fracture analysis of adhesive joints in wind turbine blades

    DEFF Research Database (Denmark)

    Eder, Martin Alexander; Bitsche, Robert

    2015-01-01

    Modern wind turbine rotor blades are usually made from fibre-reinforced composite subcomponents. In the final assembly stage, these subcomponents are bonded together by several adhesive joints. One important adhesive joint is situated at the trailing edge, which refers to the downstream edge where...... information is scarce. This paper is concerned with the fracture analysis of adhesive joints in general, with a particular focus on trailing edges. For that, the energy release rates in prescribed cracks present in the bond line of a generic trailing edge joint are investigated. In connection...... with this examination, the paper elucidates the influence of geometrical non-linearity in form of local buckling on both the increase of the energy release rate and the change of mode mixity. First, experimental results on adhesively bonded small-scale subcomponents are presented. Thereafter, a practical approach...

  13. Wind turbine wake visualization and characteristics analysis by Doppler lidar.

    Science.gov (United States)

    Wu, Songhua; Liu, Bingyi; Liu, Jintao; Zhai, Xiaochun; Feng, Changzhong; Wang, Guining; Zhang, Hongwei; Yin, Jiaping; Wang, Xitao; Li, Rongzhong; Gallacher, Daniel

    2016-05-16

    Wind power generation is growing fast as one of the most promising renewable energy sources that can serve as an alternative to fossil fuel-generated electricity. When the wind turbine generator (WTG) extracts power from the wind, the wake evolves and leads to a considerable reduction in the efficiency of the actual power generation. Furthermore, the wake effect can lead to the increase of turbulence induced fatigue loads that reduce the life time of WTGs. In this work, a pulsed coherent Doppler lidar (PCDL) has been developed and deployed to visualize wind turbine wakes and to characterize the geometry and dynamics of wakes. As compared with the commercial off-the-shelf coherent lidars, the PCDL in this work has higher updating rate of 4 Hz and variable physical spatial resolution from 15 to 60 m, which improves its capability to observation the instantaneous turbulent wind field. The wind speed estimation method from the arc scan technique was evaluated in comparison with wind mast measurements. Field experiments were performed to study the turbulent wind field in the vicinity of operating WTGs in the onshore and offshore wind parks from 2013 to 2015. Techniques based on a single and a dual Doppler lidar were employed for elucidating main features of turbine wakes, including wind velocity deficit, wake dimension, velocity profile, 2D wind vector with resolution of 10 m, turbulence dissipation rate and turbulence intensity under different conditions of surface roughness. The paper shows that the PCDL is a practical tool for wind energy research and will provide a significant basis for wind farm site selection, design and optimization.

  14. Wind energy mission analysis. Final report, appendices A--J. [USA

    Energy Technology Data Exchange (ETDEWEB)

    1977-02-18

    Information is presented concerning meteorological data and supporting analyses, gross energy consumption patterns and end-use analysis, analysis for industrial applications of wind energy conversion systems (WECS), analysis for residential applications of WECS, analysis for application of WECS to communities remote from utility grids, analysis for agricultural applications of WECS, regional evaluation of the economics of wind turbine generation to the U. S. electric utility district, impact of storage on WECS, financial analysis techniques, and system spacing.

  15. Multi-hazard response analysis of a 5MW offshore wind turbine

    DEFF Research Database (Denmark)

    Katsanos, Evangelos; Sanz, A. Arrospide; Georgakis, Christos T.

    2017-01-01

    Wind energy has already dominant role on the scene of the clean energy production. Well-promising markets, like China, India, Korea and Latin America are the fields of expansion for new wind turbines mainly installed in offshore environment, where wind, wave and earthquake loads threat the struct......Wind energy has already dominant role on the scene of the clean energy production. Well-promising markets, like China, India, Korea and Latin America are the fields of expansion for new wind turbines mainly installed in offshore environment, where wind, wave and earthquake loads threat...... the structural integrity and reliability of these energy infrastructures. Along these lines, a multi-hazard environment was considered herein and the structural performance of a 5 MW offshore wind turbine was assessed through time domain analysis. A fully integrated model of the offshore structure consisting...

  16. Analysis and estimation of transient stability for a grid-connected wind turbine with induction generator

    DEFF Research Database (Denmark)

    Li, H.; Zhao, B.; Yang, C.

    2011-01-01

    Increasing levels of wind energy in modern electrical power system is initiating a need for accurate analysis and estimation of transient stability of wind turbine generation systems. This paper investigates the transient behaviors and possible direct methods for transient stability evaluation...... of a grid-connected wind turbine with squirrel cage induction generator (SCIG). Firstly, by using an equivalent lump mass method, a three-mass wind turbine equivalent model is proposed considering both the blades and the shaft flexibility of the wind turbine drive train system. Combined with the detailed...... electromagnetic transient models of a SCIG, the transient behaviors of the wind turbine generation system during a three-phase fault are simulated and compared with the traditional models. Secondly, in order to quickly estimate the transient stability limit of the wind turbine generation system, a direct method...

  17. A study on the survey of wind energy resources for potential areas

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyung Ho; Kim, Keon Hoon; Yoo, Seung Won; Choi, Chang Joon; Jung Jong Ahn [Korea Inst. of Energy Research, Taejon (Korea, Republic of)

    1995-12-01

    Among the wind energy utilization projects, the siting work for wind turbine installation is one of the most important procedure because the wind energy distribution is very different regionally and wind energy density influences greatly to the feasibility of wind energy utilization. So, the potential sites of wind generating in our country must be surveyed and analyzed the feasibility of wind energy utilization. In addition to this, the technique of wind energy prediction considered of the topography, surface roughness and obstacle condition must be established for the reliable analysis of wind energy utilization. The contents carried out in this project are shown below, 1. Determining of the measuring sites of wind data - Wyoulryung-ri, Youngrag-ri, Gapa-ri in Cheju Province - Heul-ri, Gangwon Province. 2. Analysis of wind energy at measuring sites The characteristics of wind energy at the measured sites were analysed. It will be continued to measure the wind data by wind data logger. 3. A study on wind energy prediction technique It was studied how to obtain the topographic map data for using WAsP(WIndAtlas Analysis and Application Program). (author). 21 refs., 59 figs., 19 tabs.

  18. Unsteady aerodynamic analysis for offshore floating wind turbines under different wind conditions.

    Science.gov (United States)

    Xu, B F; Wang, T G; Yuan, Y; Cao, J F

    2015-02-28

    A free-vortex wake (FVW) model is developed in this paper to analyse the unsteady aerodynamic performance of offshore floating wind turbines. A time-marching algorithm of third-order accuracy is applied in the FVW model. Owing to the complex floating platform motions, the blade inflow conditions and the positions of initial points of vortex filaments, which are different from the fixed wind turbine, are modified in the implemented model. A three-dimensional rotational effect model and a dynamic stall model are coupled into the FVW model to improve the aerodynamic performance prediction in the unsteady conditions. The effects of floating platform motions in the simulation model are validated by comparison between calculation and experiment for a small-scale rigid test wind turbine coupled with a floating tension leg platform (TLP). The dynamic inflow effect carried by the FVW method itself is confirmed and the results agree well with the experimental data of a pitching transient on another test turbine. Also, the flapping moment at the blade root in yaw on the same test turbine is calculated and compares well with the experimental data. Then, the aerodynamic performance is simulated in a yawed condition of steady wind and in an unyawed condition of turbulent wind, respectively, for a large-scale wind turbine coupled with the floating TLP motions, demonstrating obvious differences in rotor performance and blade loading from the fixed wind turbine. The non-dimensional magnitudes of loading changes due to the floating platform motions decrease from the blade root to the blade tip. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  19. Wind turbine reliability : a database and analysis approach.

    Energy Technology Data Exchange (ETDEWEB)

    Linsday, James (ARES Corporation); Briand, Daniel; Hill, Roger Ray; Stinebaugh, Jennifer A.; Benjamin, Allan S. (ARES Corporation)

    2008-02-01

    The US wind Industry has experienced remarkable growth since the turn of the century. At the same time, the physical size and electrical generation capabilities of wind turbines has also experienced remarkable growth. As the market continues to expand, and as wind generation continues to gain a significant share of the generation portfolio, the reliability of wind turbine technology becomes increasingly important. This report addresses how operations and maintenance costs are related to unreliability - that is the failures experienced by systems and components. Reliability tools are demonstrated, data needed to understand and catalog failure events is described, and practical wind turbine reliability models are illustrated, including preliminary results. This report also presents a continuing process of how to proceed with controlling industry requirements, needs, and expectations related to Reliability, Availability, Maintainability, and Safety. A simply stated goal of this process is to better understand and to improve the operable reliability of wind turbine installations.

  20. Sharing wind power forecasts in electricity markets: A numerical analysis

    DEFF Research Database (Denmark)

    Exizidis, Lazaros; Pinson, Pierre; Kazempour, Jalal

    2016-01-01

    In an electricity pool with significant share of wind power, all generators including conventional and wind power units are generally scheduled in a day-ahead market based on wind power forecasts. Then, a real-time market is cleared given the updated wind power forecast and fixed day......-ahead decisions to adjust power imbalances. This sequential market-clearing process may cope with serious operational challenges such as severe power shortage in real-time due to erroneous wind power forecasts in day-ahead market. To overcome such situations, several solutions can be considered such as adding...... flexible resources to the system. In this paper, we address another potential solution based on information sharing in which market players share their own wind power forecasts with others in day-ahead market. This solution may improve the functioning of sequential market-clearing process through making...

  1. Condition analysis and operating lifetime extension concepts for wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Korzeniewski, Thomas [GMA-Engineering GmbH, Hamburg (Germany). Business Unit Wind Energy

    2014-11-01

    In Germany the basis for the expansion of wind energy was already laid at the beginning of the 1990s. Hence, the first wind turbines already started to reach the end of their permitted lifetime. At that time as today the different wind turbine types were engineered for an operational lifetime of 20 years. As reliable wind turbines types were already available in the 1990s, it is technically and commercially reasonable to consider the extension of their operational lifetime. Of particular interest is the lifetime extension of wind turbine types installed in the beginning of the 2000s. During that period many wind turbine types were launched which absolutely correspond to state-of-the-art technology.

  2. Analysis and design of bend-twist coupled wind turbine blades

    DEFF Research Database (Denmark)

    Stäblein, Alexander R.

    2016-01-01

    beam theory are not necessarily valid. This chapter reviews the effects of anisotropic material on the structural response of beams and identifies those relevant for wind turbine blade analysis. A framework suitable for the structural analysis of wind turbine blades is proposed and guidance...... for the design of bend-twist coupled blades is given....

  3. Coupled dynamic response analysis of a multi-column tension-leg-type floating wind turbine

    Science.gov (United States)

    Zhao, Yong-sheng; Yang, Jian-min; He, Yan-ping; Gu, Min-tong

    2016-07-01

    This paper presents a coupled dynamic response analysis of a multi-column tension-leg-type floating wind turbine (WindStar TLP system) under normal operation and parked conditions. Wind-only load cases, wave-only load cases and combined wind and wave load cases were analyzed separately for the WindStar TLP system to identify the dominant excitation loads. Comparisons between an NREL offshore 5-MW baseline wind turbine installed on land and the WindStar TLP system were performed. Statistics of selected response variables in specified design load cases (DLCs) were obtained and analyzed. It is found that the proposed WindStar TLP system has small dynamic responses to environmental loads and it thus has almost the same mean generator power output under operating conditions as the land-based system. The tension mooring system has a sufficient safety factor, and the minimum tendon tension is always positive in all selected DLCs. The ratio of ultimate load of the tower base fore-aft bending moment for the WindStar TLP system versus the land-based system can be as high as 1.9 in all of the DLCs considered. These results will help elucidate the dynamic characteristics of the proposed WindStar TLP system, identify the difference in load effect between it and land-based systems, and thus make relevant modifications to the initial design for the WindStar TLP system.

  4. Aeroelastic analysis facilities for UK wind turbines. Main report

    Energy Technology Data Exchange (ETDEWEB)

    McIver, D.B.; Wooton, L.R.

    1984-04-01

    The results of a study to assess the suitability of existing wind turbine aeroelastic computer programs for a long-term commitment of the UK to wind turbine design are presented. The assessment of the programs has been made on the basis of how they compare with modern software engineering practice; the perceived future requirements of wind turbine design; the validity of their theoretical bases and their available facilities. It is concluded that there does not yet appear to be a definitive mathematical formulation of the wind turbine aeroelastic problem.

  5. The Comparative Analysis of Inductor and Reluctance Wind Generators

    Science.gov (United States)

    Kamoliņš, Edmunds

    2009-01-01

    In the presented work two designs of brushless generators are compared: inductor and reluctance. Both designs are multipolar and also can be applied as directly driven wind generators. Both one and the second designs are basically similar, but in the inductor generator are windings of excitation or permanent magnets which complicate a design, increase consumption of the copper and energy losses. In work shown that reluctance generator has no winding of excitation, it is simple and more reliable, it has less weight. It's more competitive for use in low power wind plants.

  6. Reliability analysis of wind turbines exposed to dynamic loads

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2014-01-01

    Wind turbines are exposed to highly dynamic loads that cause fatigue and extreme load effects which are subject to significant uncertainties. Further, reduction of cost of energy for wind turbines are very important in order to make wind energy competitive compared to other energy sources......, substructure and foundation considering especially fatigue loads. The function of a wind turbine is highly dependent on many electrical and mechanical components as well as a control system also reliability aspects of these components are discussed and it is described how there reliability influences...

  7. Modeling and analysis of doubly fed induction generator wind energy systems

    CERN Document Server

    Fan, Lingling

    2015-01-01

    Wind Energy Systems: Modeling, Analysis and Control with DFIG provides key information on machine/converter modelling strategies based on space vectors, complex vector, and further frequency-domain variables. It includes applications that focus on wind energy grid integration, with analysis and control explanations with examples. For those working in the field of wind energy integration examining the potential risk of stability is key, this edition looks at how wind energy is modelled, what kind of control systems are adopted, how it interacts with the grid, as well as suitable study

  8. Wind speed analysis in the province of Alicante, Spain. Potential for small-scale wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Cabello, M.; Orza, J.A.G. [SCOLAb, Fisica Aplicada, Universidad Miguel Hernandez, 03202 Elche (Spain)

    2010-12-15

    The statistical characteristics of the wind speed in the province of Alicante, southeastern Spain, have been analyzed using 9-year wind data recorded at 2 m above the ground by 17 weather stations belonging to the Valencian Institute for Agriculture Research (IVIA). The overall mean wind speed in the area is 1.7 m/s with the windy regions located at the northwest side in the highlands. A clear seasonal and daily pattern is shown with maximum in spring-summer during the central hours of the day, influenced by the sea breeze; and minimum in autumn-winter at night. The wind frequency distributions show two and three modes. The sum-lognormal model is found to be a good fit with very high correlation in all the sites. The extrapolation to 10 m with the power law and the wind shear exponent {alpha}, shows a large underestimation in the northern coastal sites and a good agreement in the innermost locations, when compared to measurements done at 10 m in a number of stations. (author)

  9. Spectral Analysis of Geomagnetic Activity Indices and Solar Wind Parameters

    Directory of Open Access Journals (Sweden)

    Jung-Hee Kim

    2014-06-01

    Full Text Available Solar variability is widely known to affect the interplanetary space and in turn the Earth’s electromagnetical environment on the basis of common periodicities in the solar and geomagnetic activity indices. The goal of this study is twofold. Firstly, we attempt to associate modes by comparing a temporal behavior of the power of geomagnetic activity parameters since it is barely sufficient searching for common peaks with a similar periodicity in order to causally correlate geomagnetic activity parameters. As a result of the wavelet transform analysis we are able to obtain information on the temporal behavior of the power in the velocity of the solar wind, the number density of protons in the solar wind, the AE index, the Dst index, the interplanetary magnetic field, B and its three components of the GSM coordinate system, BX, BY, BZ. Secondly, we also attempt to search for any signatures of influence on the space environment near the Earth by inner planets orbiting around the Sun. Our main findings are as follows: (1 Parameters we have investigated show periodicities of ~ 27 days, ~ 13.5 days, ~ 9 days. (2 The peaks in the power spectrum of BZ appear to be split due to an unknown agent. (3 For some modes powers are not present all the time and intervals showing high powers do not always coincide. (4 Noticeable peaks do not emerge at those frequencies corresponding to the synodic and/or sidereal periods of Mercury and Venus, which leads us to conclude that the Earth’s space environment is not subject to the shadow of the inner planets as suggested earlier.

  10. Analysis and Tests of Pultruded Blades for Wind Turbine Rotors

    Energy Technology Data Exchange (ETDEWEB)

    Cheney, M. C.(PS Enterprises, Glastonbury, Connecticut); Olsen, T.; Quandt, G.; Archidiacono, P.

    1999-07-19

    PS Enterprises, Inc. investigated a flexible, downwind, free-yaw, five-blade rotor system employing pultruded blades. A rotor was designed, manufactured and tested in the field. A preliminary design study and proof of concept test were conducted to assess the feasibility of using pultruded blades for wind turbine rotors. A 400 kW turbine was selected for the design study and a scaled 80 kW rotor was fabricated and field tested as a demonstration of the concept. The design studies continued to support the premise that pultruded blades offer the potential for significant reductions in rotor weight and cost. The field test provided experimental performance and loads data that compared well with predictions using the FLEXDYNE aeroelastic analysis. The field test also demonstrated stable yaw behavior and the absence of stall flutter over the wind conditions tested. During the final year of the contract, several studies were conducted by a number of independent consultants to address specific technical issues related to pultruded blades that could impact the commercial viability of turbines using this technology. The issues included performance, tower strikes, yaw stability, stall flutter, fatigue, and costs. While the performance of straight pultruded blades was projected to suffer a penalty of about 13% over fully twisted and tapered blades, the study showed that an aerodynamic fairing over the inner 40% could recover 85% of that loss while still keeping the blade cost well below that of conventional blades. Other results of the study showed that with proper design, rotors using pultruded blades could operate without aeroelastic problems, have acceptable fatigue life, and cost less than half that of rotors employing conventionally manufactured blades.

  11. Recent ATLAS Articles on WLAP

    CERN Multimedia

    Goldfarb, S

    2005-01-01

    As reported in the September 2004 ATLAS eNews, the Web Lecture Archive Project is a system for the archiving and publishing of multimedia presentations, using the Web as medium. We list here newly available WLAP items relating to ATLAS: Atlas Software Week Plenary 6-10 December 2004 North American ATLAS Physics Workshop (Tucson) 20-21 December 2004 (17 talks) Physics Analysis Tools Tutorial (Tucson) 19 December 2004 Full Chain Tutorial 21 September 2004 ATLAS Plenary Sessions, 17-18 February 2005 (17 talks) Coming soon: ATLAS Tutorial on Electroweak Physics, 14 Feb. 2005 Software Workshop, 21-22 February 2005 Click here to browse WLAP for all ATLAS lectures.

  12. Wind energy analysis based on maximum entropy principle (MEP)-type distribution function

    Energy Technology Data Exchange (ETDEWEB)

    Akpinar, S. [Physics Department, Firat University, 23279, Elazig (Turkey); Kavak Akpinar, E. [Mechanical Engineering Department, Firat University, 23279, Elazig (Turkey)

    2007-04-15

    This paper reports an analysis of the wind characteristics of four stations (Elazig-Maden, Elazig-Keban, Elazig, Elazig-Agin) that have been investigated over a period of 8 years (1998-2005). The probabilistic distributions of wind speed are a critical piece of information needed in the assessment of wind energy potential, which have been conventionally described by various empirical correlations. Among the empirical correlations, the Weibull distribution has been the most popular one due to its ability to fit most accurately the variety of wind speed data measured at different geographical locations in the world. This study develops a theoretical approach to the analytical determination of wind speed distributions through application of the maximum entropy principle (MEP). The statistical analysis parameter based on wind power density is used as the suitable judgment criterion for the distribution functions. It is shown that the MEP type distributions not only agree better with a variety of measured wind speed data than the conventionally used empirical Weibull distribution but also can represent the wind power density much more accurately. Therefore, the MEP type distributions are more suitable for assessment of the wind energy potential and the performance of wind energy conversion systems. (author)

  13. Wind energy Computerized Maintenance Management System (CMMS) : data collection recommendations for reliability analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Valerie A.; Ogilvie, Alistair; Veers, Paul S.

    2009-09-01

    This report addresses the general data requirements for reliability analysis of fielded wind turbines and other wind plant equipment. The report provides a list of the data needed to support reliability and availability analysis, and gives specific recommendations for a Computerized Maintenance Management System (CMMS) to support automated analysis. This data collection recommendations report was written by Sandia National Laboratories to address the general data requirements for reliability analysis of fielded wind turbines. This report is intended to help the reader develop a basic understanding of what data are needed from a Computerized Maintenance Management System (CMMS) and other data systems, for reliability analysis. The report provides: (1) a list of the data needed to support reliability and availability analysis; and (2) specific recommendations for a CMMS to support automated analysis. Though written for reliability analysis of wind turbines, much of the information is applicable to a wider variety of equipment and a wider variety of analysis and reporting needs.

  14. Interactive microbial distribution analysis using BioAtlas

    DEFF Research Database (Denmark)

    Lund, Jesper; List, Markus; Baumbach, Jan

    2017-01-01

    Massive amounts of 16S rRNA sequencing data have been stored in publicly accessible databases, such as GOLD, SILVA, GreenGenes (GG), and the Ribosomal Database Project (RDP). Many of these sequences are tagged with geo-locations. Nevertheless, researchers currently lack a user-friendly tool...... body maps and (iii) user-defined maps. It further allows for (iv) uploading of own sample data, which can be placed on existing maps to (v) browse the distribution of the associated taxonomies. Finally, BioAtlas enables users to (vi) contribute custom maps (e.g. for plants or animals) and to map...

  15. CFD analysis for H-rotor Darrieus turbine as a low speed wind energy converter

    OpenAIRE

    Mohamed, M.H.; Ali, A.M.; Hafiz, A.A.

    2015-01-01

    Vertical axis wind turbines like the Darrieus turbine appear to be promising for the conditions of low wind speed, but suffer from a low efficiency compared to horizontal axis turbines. A fully detailed numerical analysis is introduced in this work to improve the global performance of this wind turbine. A comparison between ANSYS Workbench and Gambit meshing tools for the numerical modeling is performed to summarize a final numerical sequence for the Darrieus rotor performance. Then, this mod...

  16. ATLAS user analysis on private cloud resources at GoeGrid

    Science.gov (United States)

    Glaser, F.; Nadal Serrano, J.; Grabowski, J.; Quadt, A.

    2015-12-01

    User analysis job demands can exceed available computing resources, especially before major conferences. ATLAS physics results can potentially be slowed down due to the lack of resources. For these reasons, cloud research and development activities are now included in the skeleton of the ATLAS computing model, which has been extended by using resources from commercial and private cloud providers to satisfy the demands. However, most of these activities are focused on Monte-Carlo production jobs, extending the resources at Tier-2. To evaluate the suitability of the cloud-computing model for user analysis jobs, we developed a framework to launch an ATLAS user analysis cluster in a cloud infrastructure on demand and evaluated two solutions. The first solution is entirely integrated in the Grid infrastructure by using the same mechanism, which is already in use at Tier-2: A designated Panda-Queue is monitored and additional worker nodes are launched in a cloud environment and assigned to a corresponding HTCondor queue according to the demand. Thereby, the use of cloud resources is completely transparent to the user. However, using this approach, submitted user analysis jobs can still suffer from a certain delay introduced by waiting time in the queue and the deployed infrastructure lacks customizability. Therefore, our second solution offers the possibility to easily deploy a totally private, customizable analysis cluster on private cloud resources belonging to the university.

  17. Design and analysis of full pitch winding and concentrated stator ...

    Indian Academy of Sciences (India)

    the winding, (ii) low cogging torque and permanent magnet (PM) weight. The basic machine configuration is an 8 salient pole rotor and 6 salient pole stator with concentrated windings. Permanent Magnets are fixed to the stator pole. Figure 1 shows this machine configuration. FRM for low-speed servo drive application was ...

  18. Optical monitoring and operational modal analysis of large wind turbines

    NARCIS (Netherlands)

    Özbek, M.

    2013-01-01

    Identification of the dynamic properties and the corresponding structural response of wind turbines is essential for optimizing the energy produced, ensuring safe and reliable operation and increasing the life-time of the system. As the sizes of modern wind turbines increase, their dynamic behaviors

  19. Analysis of strong wind events around Adelie Land, East Antarctica

    Directory of Open Access Journals (Sweden)

    G. Mastrantonio

    2003-06-01

    Full Text Available Strong wind events at Dumont d'Urville (DdU, an East Antarctic coastal station, and Dome C, an interior station, were studied to determine if the wind along the Adelie Land coast increases with the approach of the depression from the west of the site or after its passage to the east of it. The events for the year 1993 were studied using synoptic observations, mean sea level pressure charts and composite infrared satellite images. It was found that the winds are enhanced with the approach of a depression from the west towards the DdU coast. The wind increases in response to the decreasing pressure at the coastal site and increasing downslope pressure difference (dp. The wind starts decreasing once the system moves to the east of DdU and the pressure at DdU starts building up, as reported in some earlier studies. The response of wind to the approaching depression is not the same for all the events but depends on the downslope pressure difference and the movement of the depression that is often conditioned by the presence of a blocking high to the northeast. The wind comes down if the system starts penetrating inland due to the presence of the high pressure ridge to the northeast and decreasing dp. It is observed that the winds at Dome C increase to as high as 17 m s-1 with the inland penetration of the depression.

  20. Statistical analysis of wind speed for electrical power generation in ...

    African Journals Online (AJOL)

    Also, the results have shown that Jos, Kano and Minna fall in class 4 and therefore suitable for both off grid and grid connected modes. In addition, the effects of c and k parameters on the probability distribution functions have been presented. Keywords: Wind speed - probability - density function – wind energy conversion ...

  1. Assessment and analysis of wind energy generation and power ...

    African Journals Online (AJOL)

    Keywords: wind energy- wind speed- Weibull distribution-capacity factor-power output. Résumé ... greenhouse effect. According to a publication of the international agency of the energy, the world production of electricity should double during the next 25 years. Hence, to ... reduction of the fossils use and to reduce carbon.

  2. Wind speed power spectrum analysis for Bushland, Texas

    Energy Technology Data Exchange (ETDEWEB)

    Eggleston, E.D. [USDA-Agricultural Research Service, Bushland, TX (United States)

    1996-12-31

    Numerous papers and publications on wind turbulence have referenced the wind speed spectrum presented by Isaac Van der Hoven in his article entitled Power Spectrum of Horizontal Wind Speed Spectrum in the Frequency Range from 0.0007 to 900 Cycles per Hour. Van der Hoven used data measured at different heights between 91 and 125 meters above the ground, and represented the high frequency end of the spectrum with data from the peak hour of hurricane Connie. These facts suggest we should question the use of his power spectrum in the wind industry. During the USDA - Agricultural Research Service`s investigation of wind/diesel system power storage, using the appropriate wind speed power spectrum became a significant issue. We developed a power spectrum from 13 years of hourly average data, 1 year of 5 minute average data, and 2 particularly gusty day`s 1 second average data all collected at a height of 10 meters. While the general shape is similar to the Van der Hoven spectrum, few of his peaks were found in the Bushland spectrum. While higher average wind speeds tend to suggest higher amplitudes in the high frequency end of the spectrum, this is not always true. Also, the high frequency end of the spectrum is not accurately described by simple wind statistics such as standard deviation and turbulence intensity. 2 refs., 5 figs., 1 tab.

  3. Performance analysis of voltage regulation in diesel-wind generation

    African Journals Online (AJOL)

    generated by the two sources one source is the diesel engine generator and the other source is the wind energy conversion system the supply is provided to the isolated load. The voltage is regulated at the load side .The electrical energy produced by the wind turbine at constant speed is connected to the specific load by ...

  4. Analysis of North Sea Offshore Wind Power Variability

    NARCIS (Netherlands)

    Buatois, A.; Gibescu, M.; Rawn, B.G.; Van der Meijden, M.A.M.M.

    2014-01-01

    This paper evaluates, for a 2030 scenario, the impact on onshore power systems in terms of the variability of the power generated by 81 GW of offshore wind farms installed in the North Sea. Meso-scale reanalysis data are used as input for computing the hourly power production for offshore wind

  5. Load flow analysis for variable speed offshore wind farms

    DEFF Research Database (Denmark)

    Chen, Zhe; Zhao, Menghua; Blaabjerg, Frede

    2009-01-01

    A serial AC-DC integrated load flow algorithm for variable speed offshore wind farms is proposed. It divides the electrical system of a wind farm into several local networks, and different load flow methods are used for these local networks sequentially. This method is fast, more accurate, and many...... factors such as the different wind farm configurations, the control of wind turbines and the power losses of pulse width modulation converters are considered. The DC/DC converter model is proposed and integrated into load flow algorithm by modifying the Jacobian matrix. Two iterative methods are proposed...... and integrated into the load flow algorithm: one takes into account the control strategy of converters and the other considers the power losses of converters. In addition, different types of variable speed wind turbine systems with different control methods are investigated. Finally, the method is demonstrated...

  6. Computational design and analysis of flatback airfoil wind tunnel experiment.

    Energy Technology Data Exchange (ETDEWEB)

    Mayda, Edward A. (University of California, Davis, CA); van Dam, C.P. (University of California, Davis, CA); Chao, David D. (University of California, Davis, CA); Berg, Dale E.

    2008-03-01

    A computational fluid dynamics study of thick wind turbine section shapes in the test section of the UC Davis wind tunnel at a chord Reynolds number of one million is presented. The goals of this study are to validate standard wind tunnel wall corrections for high solid blockage conditions and to reaffirm the favorable effect of a blunt trailing edge or flatback on the performance characteristics of a representative thick airfoil shape prior to building the wind tunnel models and conducting the experiment. The numerical simulations prove the standard wind tunnel corrections to be largely valid for the proposed test of 40% maximum thickness to chord ratio airfoils at a solid blockage ratio of 10%. Comparison of the computed lift characteristics of a sharp trailing edge baseline airfoil and derived flatback airfoils reaffirms the earlier observed trend of reduced sensitivity to surface contamination with increasing trailing edge thickness.

  7. Performance analysis of wind turbine systems under different parameters effect

    Energy Technology Data Exchange (ETDEWEB)

    Salih, Salih Mohammed; Taha, Mohammed Qasim; Alawsaj, Mohammed K. [College of Engineering, University of Anbar (Iraq)

    2012-07-01

    In this paper, simulation models are used to study the performance of small power systems based on different weather parameters. The results are extracted using Matlab software program for analyzing the performance of two wind turbines: Whisper-500 3.2KW and NY-WSR1204 600W which have the same type of permanent magnetic alternators (three phase and 16 poles). Different parameters can affect on the performance of wind turbines which are: the wind speed air density, air pressure, temperature and the length of blades for wind generators. The mathematical results related the previous mentioned parameters are analyzed in order to determine the sensitivity of input power on the output of wind generators.

  8. Coupling modeling and analysis of a wind energy converter

    Directory of Open Access Journals (Sweden)

    Jie-jie Li

    2016-06-01

    Full Text Available In this article, the numerical simulation of a 2.0-MW wind energy converter coupling is achieved by three-dimensional computer-aided design modeling technique and finite element method. The static performances and the buckling characteristics of the diaphragm coupling are investigated. The diaphragm coupling is divided into three substructures, namely, torque input end, the middle section, and the torque output end. Considering the assembly and contact conditions, the simulation analysis for stress responses of the diaphragm coupling is carried out. The buckling factor and buckling mode of the diaphragms are obtained, and the geometric parameters of the diaphragms are optimized according to their buckling characteristics. The relationship between the pretightening force of the bolts, which tighten the friction flange and the friction plate, and the sliding torque is given by an empirical formula. The reasonable ranges of the pretightening force and tighten torque of the bolts are recommended. The fatigue analysis of the diaphragms is completed, and the results show that the diaphragms are competent to the designed life of the diaphragm coupling.

  9. An Analysis of Variable-Speed Wind Turbine Power-Control Methods with Fluctuating Wind Speed

    Directory of Open Access Journals (Sweden)

    Seung-Il Moon

    2013-07-01

    Full Text Available Variable-speed wind turbines (VSWTs typically use a maximum power-point tracking (MPPT method to optimize wind-energy acquisition. MPPT can be implemented by regulating the rotor speed or by adjusting the active power. The former, termed speed-control mode (SCM, employs a speed controller to regulate the rotor, while the latter, termed power-control mode (PCM, uses an active power controller to optimize the power. They are fundamentally equivalent; however, since they use a different controller at the outer control loop of the machine-side converter (MSC controller, the time dependence of the control system differs depending on whether SCM or PCM is used. We have compared and analyzed the power quality and the power coefficient when these two different control modes were used in fluctuating wind speeds through computer simulations. The contrast between the two methods was larger when the wind-speed fluctuations were greater. Furthermore, we found that SCM was preferable to PCM in terms of the power coefficient, but PCM was superior in terms of power quality and system stability.

  10. Thermal and Alignment Analysis of the Instrument-Level ATLAS Thermal Vacuum Test

    Science.gov (United States)

    Bradshaw, Heather

    2012-01-01

    This paper describes the thermal analysis and test design performed in preparation for the ATLAS thermal vacuum test. NASA's Advanced Topographic Laser Altimeter System (ATLAS) will be flown as the sole instrument aboard the Ice, Cloud, and land Elevation Satellite-2 (ICESat-2). It will be used to take measurements of topography and ice thickness for Arctic and Antarctic regions, providing crucial data used to predict future changes in worldwide sea levels. Due to the precise measurements ATLAS is taking, the laser altimeter has very tight pointing requirements. Therefore, the instrument is very sensitive to temperature-induced thermal distortions. For this reason, it is necessary to perform a Structural, Thermal, Optical Performance (STOP) analysis not only for flight, but also to ensure performance requirements can be operationally met during instrument-level thermal vacuum testing. This paper describes the thermal model created for the chamber setup, which was used to generate inputs for the environmental STOP analysis. This paper also presents the results of the STOP analysis, which indicate that the test predictions adequately replicate the thermal distortions predicted for flight. This is a new application of an existing process, as STOP analyses are generally performed to predict flight behavior only. Another novel aspect of this test is that it presents the opportunity to verify pointing results of a STOP model, which is not generally done. It is possible in this case, however, because the actual pointing will be measured using flight hardware during thermal vacuum testing and can be compared to STOP predictions.

  11. Wind speed analysis in La Vainest, Mexico: a bimodal probability distribution case

    Energy Technology Data Exchange (ETDEWEB)

    Jaramillo, O.A.; Borja, M.A. [Energias No Convencionales, Morelos (Mexico). Instituto de Investigaciones Electricas

    2004-08-01

    The statistical characteristics of the wind speed in La Vainest, Oxoic, Mexico, have been analyzed by using wind speed data recorded by Instituto de Investigaciones Electricas (IIE). By grouping the observations by annual, seasonal and wind direction, we show that the wind speed distribution, with calms included, is not represented by the typical two-parameter Weibull function. A mathematical formulation by using a bimodal Weibull and Weibull probability distribution function (PDF) has been developed to analyse the wind speed frequency distribution in that region. The model developed here can be applied for similar regions where the wind speed distribution presents a bimodal PDF. The two-parameter Weibull wind speed distribution must not be generalised, since it is not accurate to represent some wind regimes as the case of La Ventosa, Mexico. The analysis of wind data shows that computing the capacity factor for wind power plants to be installed in La Ventosa must be carded out by means of a bimodal PDF instead of the typical Weibull PDF. Otherwise, the capacity factor will be underestimated. (author)

  12. Multi-hazard response analysis of a 5MW offshore wind turbine

    DEFF Research Database (Denmark)

    Katsanos, Evangelos; Sanz, A. Arrospide; Georgakis, Christos T.

    2017-01-01

    Wind energy has already dominant role on the scene of the clean energy production. Well-promising markets, like China, India, Korea and Latin America are the fields of expansion for new wind turbines mainly installed in offshore environment, where wind, wave and earthquake loads threat...... response of the turbine’s tower was found to be severely affected by the earthquake excitations. Moreover, fragility analysis based on acceleration capacity thresholds for the nacelle’s equipment corroborated that the earthquake excitations may adversely affect the reliability and availability of wind...

  13. Research on dynamic characteristics of wind turbine tower with different analysis methods

    Directory of Open Access Journals (Sweden)

    Ji YAO

    2015-08-01

    Full Text Available A wind turbine located in Yunnan is taken as an example in this paper. By using the analytical method and the finite element method, the modal analysis of wind turbine tower is carried out, then the structural dynamic behavior is obtained. Based on the comparison of the results from different calculation methods, the rigidity and the resonance of tower induced by wind wheel rotation are studied. The research shows that, the finite element model is simplified, while the results of this method are rich; the transient resonance inevitably appears for two times in the starting process for the flexible wind tower which has the structure of symmetry basically; while in the normal operation stage, the wind wheel would not induce the resonance for flexible tower. The research provides a theoretical basis for the design of wind turbine tower.

  14. Roadmap to the multidisciplinary design analysis and optimisation of wind energy systems

    Science.gov (United States)

    Sanchez Perez-Moreno, S.; Zaaijer, M. B.; Bottasso, C. L.; Dykes, K.; Merz, K. O.; Réthoré, P.-E.; Zahle, F.

    2016-09-01

    A research agenda is described to further encourage the application of Multidisciplinary Design Analysis and Optimisation (MDAO) methodologies to wind energy systems. As a group of researchers closely collaborating within the International Energy Agency (IEA) Wind Task 37 for Wind Energy Systems Engineering: Integrated Research, Design and Development, we have identified challenges that will be encountered by users building an MDAO framework. This roadmap comprises 17 research questions and activities recognised to belong to three research directions: model fidelity, system scope and workflow architecture. It is foreseen that sensible answers to all these questions will enable to more easily apply MDAO in the wind energy domain. Beyond the agenda, this work also promotes the use of systems engineering to design, analyse and optimise wind turbines and wind farms, to complement existing compartmentalised research and design paradigms.

  15. Combined Structural Optimization and Aeroelastic Analysis of a Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Roscher, Björn; Ferreira, Carlos Simao; Bernhammer, Lars O.

    2015-01-01

    Floating offshore wind energy poses challenges on the turbine design. A possible solution is vertical axis wind turbines, which are possibly easier to scale-up and require less components (lower maintenance) and a smaller floating structure than horizontal axis wind turbines. This paper presents...... a structural optimization and aeroelastic analysis of an optimized Troposkein vertical axis wind turbine to minimize the relation between the rotor mass and the swept area. The aeroelastic behavior of the different designs has been analyzed using a modified version of the HAWC2 code with the Actuator Cylinder...... model to compute the aerodynamics of the vertical axis wind turbine. The combined shape and topology optimization of a vertical axis wind turbine show a minimum mass to area ratio of 1.82 kg/m2 for blades with varying blade sections from a NACA 0040 at the attachment points to a NACA 0015...

  16. AN ANALYSIS OF IODINE DEFICIENCY DISORDER AND ERADICATION STRATEGIES IN THE HIGH ATLAS MOUNTAINS OF MOROCCO

    OpenAIRE

    Oldham, Elizabeth Anne; Barrett, Christopher B.; Benjelloun, Sabah; Ahanou, Brahim

    1996-01-01

    The population of the Ounein Valley in the High Atlas Mountains in Morocco is at high risk of iodine deficiency. We investigated local childrens iodine deficiency and goiter patterns as well as food consumption habits through a household survey. Median urinary iodine content and goiter analysis both reflect moderate iodine deficiency. Total fish consumption has a statistically significant, positive effect on urinary iodine content. Fish consumption, like that of salt, is closely related to ma...

  17. Risk analysis for U.S. offshore wind farms: the need for an integrated approach.

    Science.gov (United States)

    Staid, Andrea; Guikema, Seth D

    2015-04-01

    Wind power is becoming an increasingly important part of the global energy portfolio, and there is growing interest in developing offshore wind farms in the United States to better utilize this resource. Wind farms have certain environmental benefits, notably near-zero emissions of greenhouse gases, particulates, and other contaminants of concern. However, there are significant challenges ahead in achieving large-scale integration of wind power in the United States, particularly offshore wind. Environmental impacts from wind farms are a concern, and these are subject to a number of on-going studies focused on risks to the environment. However, once a wind farm is built, the farm itself will face a number of risks from a variety of hazards, and managing these risks is critical to the ultimate achievement of long-term reductions in pollutant emissions from clean energy sources such as wind. No integrated framework currently exists for assessing risks to offshore wind farms in the United States, which poses a challenge for wind farm risk management. In this "Perspective", we provide an overview of the risks faced by an offshore wind farm, argue that an integrated framework is needed, and give a preliminary starting point for such a framework to illustrate what it might look like. This is not a final framework; substantial work remains. Our intention here is to highlight the research need in this area in the hope of spurring additional research about the risks to wind farms to complement the substantial amount of on-going research on the risks from wind farms. © 2015 Society for Risk Analysis.

  18. Repowering of wind farms - A case study

    Energy Technology Data Exchange (ETDEWEB)

    Nivedh, B.S. [Quality Engineering and Software Technologies, Bangalore (India); Devi, R.P.K. [College of Engineering. Power Systems Engineering, Guindy (India); Sreevalsan, E. [Gamesa Wind Turbines India Private Limited, Chennai (India)

    2012-07-01

    The main objective of the study is to devise a method for assessing the repowering potential and to improve the energy output from the wind farms and also to understand the impact on the power quality due to repowering. With repowering, the first-generation wind turbines can be replaced with modern multi-megawatt wind turbines. To carry-out the study an old wind farm located at Kayathar, Tamilnadu is selected. The wind farm was commissioned in 1990's with a capacity of 7.35MW, which consists of 36 Wind Turbines each with the capacity of 200kW and 225kW. The present annual energy generation of the wind farm is 7350MWhr with the plant load factor of 11.41%. The intent of this study is to predict the annual energy output of the wind farm after the repowering using WAsP (Wind Atlas Analysis Application Program). Further this study analyses the power quality issues of the various Wind Turbines. In addition, the main feeder, in which the wind farm which is taken for the study also modeled and the impact on power quality due to repowering also studied. Simulations were carried out using MATLAB. The results are analyzed to understand the significance of repowering to overcome the energy crisis of the nation since the best locations for wind in India are occupied by old wind turbines. The following are the observations and conclusions from the above study. Plant load factor (PLF) increased to 24 %, Energy yield increased to more than 4 times and the capacity of the wind farm became double. And in the view of power quality, comparing to the existing Feeder, Repowered Feeder having less reactive power consumption, voltage variations and flickers except the harmonic distortion. (Author)

  19. Economic analysis of wind-powered crop drying. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Garling, W.S.; Harper, M.R.; Merchant-Geuder, L.; Welch, M.

    1980-03-01

    Potential applications of wind energy include not only large central turbines that can be utilized by utilities, but also dispersed systems for farms and other applications. The US Departments of Energy (DOE) and Agriculture (USDA) currently are establishing the feasibility of wind energy use in applications where the energy can be used as available, or stored in a simple form. These applications include production of hot water for rural sanitation, heating and cooling of rural structures and products, drying agricultural products, and irrigation. This study, funded by USDA, analyzed the economic feasibility of wind power in crop drying. Drying of corn, soybeans, rice, peanuts, tobacco, and dehydrated alfalfa were addressed.

  20. HAWCStab2 with super element foundations: A new tool for frequency analysis of offshore wind turbines

    DEFF Research Database (Denmark)

    Henriksen, Lars Christian; Hansen, Anders Melchior; Kragh, Knud Abildgaard

    HAWCStab2 is a linear frequency domain aero-elastic tool, developed by DTU Wind Energy, suitable for frequency and stability analysis of horizontal axis 3 bladed wind turbines [1]. This tool has now been extended to also handle complex offshore foundation types, such as jacket structures...

  1. Initial Economic Analysis of Utility-Scale Wind Integration in Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    2012-03-01

    This report summarizes an analysis, conducted by the National Renewable Energy Laboratory (NREL) in May 2010, of the economic characteristics of a particular utility-scale wind configuration project that has been referred to as the 'Big Wind' project.

  2. Design of Shrouded Airborne Wind Turbine & CFD Analysis

    Science.gov (United States)

    Anbreen, Faiqa; Faiqa Anbreen Collaboration

    2015-11-01

    The focus is to design a shrouded airborne wind turbine, capable to generate 70 kW to propel a leisure boat. The idea of designing an airborne turbine is to take the advantage of different velocity layers in the atmosphere. The blades have been designed using NREL S826 airfoil, which has coefficient of lift CL of 1.4 at angle of attack, 6°. The value selected for CP is 0.8. The rotor diameter is 7.4 m. The balloon (shroud) has converging-diverging nozzle design, to increase the mass flow rate through the rotor. The ratio of inlet area to throat area, Ai/At is 1.31 and exit area to throat area, Ae/At is1.15. The Solidworks model has been analyzed numerically using CFD. The software used is StarCCM +. The Unsteady Reynolds Averaged Navier Stokes Simulation (URANS) K- ɛ model has been selected, to study the physical properties of the flow, with emphasis on the performance of the turbine. Stress analysis has been done using Nastran. From the simulations, the torque generated by the turbine is approximately 800N-m and angular velocity is 21 rad/s.

  3. Design and Analysis of Jacket Substructures for Offshore Wind Turbines

    Directory of Open Access Journals (Sweden)

    I-Wen Chen

    2016-04-01

    Full Text Available This study focused on investigating various existing types of offshore jacket substructures along with a proposed twisted-tripod jacket type (modified jacket (MJ-structures. The architectures of the three-leg structure, as well as the patented twisted jacket structure motivated the design of the proposed MJ-structures. The dimensions of the structures were designed iteratively using static stress analysis to ensure that all structures had a similar level of load-carrying capability. The numerical global buckling analyses were performed for all structures after the validation by the scaled-down experiments. The local buckling strength of all compressive members was analyzed using the NORSOK standard. The results showed that the proposed MJ-structures possess excellent structural behavior and few structural nodes and components competitive with the patented twisted jacket structures, while still maintaining the advantages of low material usage similar to the three-leg jacket structures. This study provides alternatives for the initial selection and design of offshore wind turbine substructures for green energy applications.

  4. Wind River: A Wild and Scenic River Analysis: Preliminary draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Wind River meets the criteria for inclusion in the National Wild and Scenic Rivers System. Subject to valid existing rights, the minerals in Federal lands which...

  5. Analysis of extreme wind speed and precipitation using copula

    Science.gov (United States)

    Kwon, Taeyong; Yoon, Sanghoo

    2017-04-01

    The Korean peninsula is exposed to 1.3 times the average annual typhoon risk. Typhoons are tropical cyclones, accompanied by strong winds and rainfall. It brings complicated socio-economic damage. The classic natural disaster warning system is designed to take wind or rainfall separately. Detecting the dangers of typhoons caused by strong winds and heavy rain does not help. In this study, we analyzed the correlation between annual maximum wind speed and rainfall collected from meteorological observatories in Busan and Jeju Island which correspond to the typhoon danger zone. Observed data were applied to various bonding models through pseudo - observations. The Cramer-von-Mises test was used to test the suitability of the copula model and cross validation was used to select the best model. Several heavy tail distributions have been considered for marginal distribution.

  6. ANALYSIS OF A STATION BLACKOUT SCENARIO WITH AN ATLAS TEST

    Directory of Open Access Journals (Sweden)

    YEON-SIK KIM

    2013-04-01

    Full Text Available A station blackout experiment called SBO-01 was performed at the ATLAS facility. From the SBO-01 test, the station blackout scenario can be characterized into two typical phases: A first phase characterized by decay heat removal through secondary safety valves until the SG dryouts, and a second phase characterized by an energy release through a blowdown of the primary system after the SG dryouts. During the second phase, some physical phenomena of the change over a pressurizer function, i.e., the pressurizer being full before the POSRV 1st opening and then its function being taken by the RV, and the termination of normal natural circulation flow were identified. Finally, a core heatup occurred at a low core water level, although under a significant amount of PZR inventory, whose drainage seemed to be hindered owing to the pressurizer function by the RV. The transient of SBO-01 is well reproduced in the calculation using the MARS code.

  7. Millville Wind Turbine Generator: failure analysis and corrective design modification

    Energy Technology Data Exchange (ETDEWEB)

    Waldon, C. A.; Carr, M. J.; Grotzky, V. K.

    1979-07-01

    Fatigue cracks in the blade skins of the Millville Wind Turbine Generator were fractographically analyzed. It is believed they were caused by large flapwise deflections during a wind storm on December 4, 1978. The deflections caused the skin to buckle, which initiated rapidly growing fatigue cracks. Propagation continued to the leading edge, moving radially inward and outward along the leading edge radius. Communication between Rockwell and Millville resulted in a modified blade design which incorporates several corrective techniques.

  8. A Study on Structural Design and Analysis of Blade and Tower for Small Wind Turbine System

    Directory of Open Access Journals (Sweden)

    Park Hyunbum

    2016-01-01

    Full Text Available This paper performed aerodynamic, structural design and analysis of the horizontal axis blade of low noise 1kW class small wind turbine system that can be operated at homes and designed to display excellent performances in low wind velocity regions such as Korea. In terms of the material applied, glass/epoxy that is both economical and excellent in its performance was applied. Structural test was conducted to verify whether the actual movement of the blade designed is consistent with the theoretical analysis result. In addition, structural safety review was performed through the structural analysis of a tower for installing the wind turbine system developed.

  9. Stellar and wind parameters of massive stars from spectral analysis

    Science.gov (United States)

    Araya, Ignacio; Curé, Michel

    2017-11-01

    The only way to deduce information from stars is to decode the radiation it emits in an appropriate way. Spectroscopy can solve this and derive many properties of stars. In this work we seek to derive simultaneously the stellar and wind characteristics of a wide range of massive stars. Our stellar properties encompass the effective temperature, the surface gravity, the stellar radius, the micro-turbulence velocity, the rotational velocity and the Si abundance. For wind properties we consider the mass-loss rate, the terminal velocity and the line-force parameters α, k and δ (from the line-driven wind theory). To model the data we use the radiative transport code Fastwind considering the newest hydrodynamical solutions derived with Hydwind code, which needs stellar and line-force parameters to obtain a wind solution. A grid of spectral models of massive stars is created and together with the observed spectra their physical properties are determined through spectral line fittings. These fittings provide an estimation about the line-force parameters, whose theoretical calculations are extremely complex. Furthermore, we expect to confirm that the hydrodynamical solutions obtained with a value of δ slightly larger than ~ 0.25, called δ-slow solutions, describe quite reliable the radiation line-driven winds of A and late B supergiant stars and at the same time explain disagreements between observational data and theoretical models for the Wind-Momentum Luminosity Relationship (WLR).

  10. Stellar and wind parameters of massive stars from spectral analysis

    Science.gov (United States)

    Araya, I.; Curé, M.

    2017-07-01

    The only way to deduce information from stars is to decode the radiation it emits in an appropriate way. Spectroscopy can solve this and derive many properties of stars. In this work we seek to derive simultaneously the stellar and wind characteristics of A and B supergiant stars. Our stellar properties encompass the effective temperature, the surface gravity, the stellar radius, the micro-turbulence velocity, the rotational velocity and, finally, the chemical composition. For wind properties we consider the mass-loss rate, the terminal velocity and the line-force parameters (α, k and δ) obtained from the standard line-driven wind theory. To model the data we use the radiative transport code Fastwind considering the newest hydrodynamical solutions derived with Hydwind code, which needs stellar and line-force parameters to obtain a wind solution. A grid of spectral models of massive stars is created and together with the observed spectra their physical properties are determined through spectral line fittings. These fittings provide an estimation about the line-force parameters, whose theoretical calculations are extremely complex. Furthermore, we expect to confirm that the hydrodynamical solutions obtained with a value of δ slightly larger than ˜ 0.25, called δ-slow solutions, describe quite reliable the radiation line-driven winds of A and late B supergiant stars and at the same time explain disagreements between observational data and theoretical models for the Wind-Momentum Luminosity Relationship (WLR).

  11. The Coplane Analysis Technique for Three-Dimensional Wind Retrieval Using the HIWRAP Airborne Doppler Radar

    Science.gov (United States)

    Didlake, Anthony C., Jr.; Heymsfield, Gerald M.; Tian, Lin; Guimond, Stephen R.

    2015-01-01

    The coplane analysis technique for mapping the three-dimensional wind field of precipitating systems is applied to the NASA High Altitude Wind and Rain Airborne Profiler (HIWRAP). HIWRAP is a dual-frequency Doppler radar system with two downward pointing and conically scanning beams. The coplane technique interpolates radar measurements to a natural coordinate frame, directly solves for two wind components, and integrates the mass continuity equation to retrieve the unobserved third wind component. This technique is tested using a model simulation of a hurricane and compared to a global optimization retrieval. The coplane method produced lower errors for the cross-track and vertical wind components, while the global optimization method produced lower errors for the along-track wind component. Cross-track and vertical wind errors were dependent upon the accuracy of the estimated boundary condition winds near the surface and at nadir, which were derived by making certain assumptions about the vertical velocity field. The coplane technique was then applied successfully to HIWRAP observations of Hurricane Ingrid (2013). Unlike the global optimization method, the coplane analysis allows for a transparent connection between the radar observations and specific analysis results. With this ability, small-scale features can be analyzed more adequately and erroneous radar measurements can be identified more easily.

  12. The AAL project: Automated monitoring and intelligent AnaLysis for the ATLAS data taking infrastructure

    CERN Document Server

    Magnoni, L; The ATLAS collaboration; Kazarov, A

    2011-01-01

    The Trigger and Data Acquisition (TDAQ) system of the ATLAS experiment at CERN is the infrastructure responsible for filtering and transferring ATLAS experimental data from detectors to the mass storage system. It relies on a large, distributed computing environment, including thousands of computing nodes with thousands of application running concurrently. In such a complex environment, information analysis is fundamental for controlling applications behavior, error reporting and operational monitoring. During data taking runs, streams of messages sent by applications via the message reporting system together with data published from applications via information services are the main sources of knowledge about correctness of running operations. The huge flow of data produced (with an average rate of O(1-10KHz)) is constantly monitored by experts to detect problem or misbehavior. This require strong competence and experience in understanding and discovering problems and root causes, and often the meaningful in...

  13. The AAL project: automated monitoring and intelligent analysis for the ATLAS data taking infrastructure

    CERN Document Server

    Kazarov, A; The ATLAS collaboration; Magnoni, L

    2011-01-01

    The Trigger and Data Acquisition (TDAQ) system of the ATLAS experiment at CERN is the infrastructure responsible for filtering and transferring ATLAS experimental data from detectors to the mass storage system. It relies on a large, distributed computing environment, including thousands of computing nodes with thousands of application running concurrently. In such a complex environment, information analysis is fundamental for controlling applications behavior, error reporting and operational monitoring. During data taking runs, streams of messages sent by applications via the message reporting system together with data published from applications via information services are the main sources of knowledge about correctness of running operations. The huge flow of data produced (with an average rate of O(1-10KHz)) is constantly monitored by experts to detect problem or misbehavior. This require strong competence and experience in understanding and discovering problems and root causes, and often the meaningful in...

  14. Small-Signal Stability Analysis of Full-Load Converter Interfaced Wind Turbines

    DEFF Research Database (Denmark)

    Knüppel, Thyge; Akhmatov, Vladislav; Nielsen, Jørgen Nygård

    2009-01-01

    Power system stability investigations of wind farms often cover the tasks of low-voltage-fault-ride-through, voltage and reactive power control, and power balancing, but not much attention has yet been paid to the task of small-signal stability. Small-signal stability analysis needs increasing...... focus since the share of wind power increases substituting power generation from conventional power plants. Here, a study based on modal analysis is presented which investigate the effect of large scale integration of full-load converter interfaced wind turbines on inter-area oscillations in a three...... generator network. A detailed aggregated wind turbine model is employed which includes all necessary control functions. It is shown that the wind urbines have very low participation in the inter-area power oscillation....

  15. Economic feasibility analysis of a wind farm in Caldas da Rainha, Portugal

    Energy Technology Data Exchange (ETDEWEB)

    de Oliveira, Wagner Sousa; Fernandes, Antonio Jorge [Department of Economics, Management and Industrial Engineering, University of Aveiro & Campus Universitario de Santiago, 3810-193 Aveiro (Portugal)

    2012-07-01

    This paper presents the technical and economical feasibility of a wind farm. The method is applied to a potential wind farm site located in Caldas da Rainha, Portugal. The site is considered on technical and economical parameters for the complete plant and its running costs. For technical consideration wind speed, prevailing wind direction, and temperature measurements are performed by using RETScreen Climate Database and Retscreen Product Database. The economic and financial evaluation of the wind farm is made by the software RETScreen(reg. sign) International Clean Energy Project Analysis and the indicators calculated are WACC, NPV, IRR, SPB, DPB, TLCC, BCR, LCOE, RR and UPAC. The sensitivity analysis backs up the findings through the scenarios developed (Current, S1, S2 and S3).

  16. Wavelet Transform Based Higher Order Statistical Analysis of Wind and Wave Time Histories

    Science.gov (United States)

    Habib Huseni, Gulamhusenwala; Balaji, Ramakrishnan

    2017-10-01

    Wind, blowing on the surface of the ocean, imparts the energy to generate the waves. Understanding the wind-wave interactions is essential for an oceanographer. This study involves higher order spectral analyses of wind speeds and significant wave height time histories, extracted from European Centre for Medium-Range Weather Forecast database at an offshore location off Mumbai coast, through continuous wavelet transform. The time histories were divided by the seasons; pre-monsoon, monsoon, post-monsoon and winter and the analysis were carried out to the individual data sets, to assess the effect of various seasons on the wind-wave interactions. The analysis revealed that the frequency coupling of wind speeds and wave heights of various seasons. The details of data, analysing technique and results are presented in this paper.

  17. Hip fracture risk estimation based on principal component analysis of QCT atlas: a preliminary study

    Science.gov (United States)

    Li, Wenjun; Kornak, John; Harris, Tamara; Lu, Ying; Cheng, Xiaoguang; Lang, Thomas

    2009-02-01

    We aim to capture and apply 3-dimensional bone fragility features for fracture risk estimation. Using inter-subject image registration, we constructed a hip QCT atlas comprising 37 patients with hip fractures and 38 age-matched controls. In the hip atlas space, we performed principal component analysis to identify the principal components (eigen images) that showed association with hip fracture. To develop and test a hip fracture risk model based on the principal components, we randomly divided the 75 QCT scans into two groups, one serving as the training set and the other as the test set. We applied this model to estimate a fracture risk index for each test subject, and used the fracture risk indices to discriminate the fracture patients and controls. To evaluate the fracture discrimination efficacy, we performed ROC analysis and calculated the AUC (area under curve). When using the first group as the training group and the second as the test group, the AUC was 0.880, compared to conventional fracture risk estimation methods based on bone densitometry, which had AUC values ranging between 0.782 and 0.871. When using the second group as the training group, the AUC was 0.839, compared to densitometric methods with AUC values ranging between 0.767 and 0.807. Our results demonstrate that principal components derived from hip QCT atlas are associated with hip fracture. Use of such features may provide new quantitative measures of interest to osteoporosis.

  18. Analysis of ATLAS LTC-04R Test for Loop Seal Reformation Phenomena using RELAP5

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang-Gyu; Kim, Dae-Hun; Kim, Han-Gon [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    The loop seal reformation issue was selected to be the analysis topic of the DSP-04 based on the technical discussion between the participants and the operating agencies (KAERI and KINS) and domestic experts meetings. After that, KAERI performed LTC-04R test which is 4 inch top-slot cold-leg break test using ATLAS facility in December 27, 2015. KHNP CRI, as a participant of the DSP-04, performed the blind calculation and open calculation using RELAP5/Mod3.3 patch 3. This paper deals with the results of open calculation for ATLAS LTC-04R test. The results of several sensitivity analyses such as the critical flow modeling sensitivity and break flow system modeling sensitivity will be discussed. Several possible factors in the loop seal reformation behavior are examined in the sensitivity analysis. Heat loss modeling, fine break system modeling, fine loop seal nodalization and off-take modeling are not significant factor in the loop seal reformation. Still critical flow model and discharge coefficient are dominant factors. Based on the ATLAS LTC-04R, Ransom-Trapp model shows better prediction in the break flow than the Henry-Fauske model.

  19. Achievements of the ATLAS Distributed Analysis during the first run period

    CERN Document Server

    Farida, Fassi; The ATLAS collaboration

    2013-01-01

    Summary : In the LHC operations era analyzing the large data by the distributed physicists becomes a challenging task. The Computing Model of the ATLAS experiment at the LHC at CERN was designed around the concepts of grid computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with these challenges a global network known as the Worlwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. Since the start of data-taking, the ATLAS Distributed Analysis (ADA) service has been running stably with the huge amount of data. The reliability of the ADA service is high but steadily improving; grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters provides user support and communicates user problems to the sites. The ATLAS Grid Computing Model is reviewed in this talk. Emphasis is given to ADA system. Description : The ce...

  20. Incorporation of a Wind Generator Model into a Dynamic Power Flow Analysis

    Directory of Open Access Journals (Sweden)

    Angeles-Camacho C.

    2011-07-01

    Full Text Available Wind energy is nowadays one of the most cost-effective and practical options for electric generation from renewable resources. However, increased penetration of wind generation causes the power networks to be more depend on, and vulnerable to, the varying wind speed. Modeling is a tool which can provide valuable information about the interaction between wind farms and the power network to which they are connected. This paper develops a realistic characterization of a wind generator. The wind generator model is incorporated into an algorithm to investigate its contribution to the stability of the power network in the time domain. The tool obtained is termed dynamic power flow. The wind generator model takes on account the wind speed and the reactive power consumption by induction generators. Dynamic power flow analysis is carried-out using real wind data at 10-minute time intervals collected for one meteorological station. The generation injected at one point into the network provides active power locally and is found to reduce global power losses. However, the power supplied is time-varying and causes fluctuations in voltage magnitude and power fl ows in transmission lines.

  1. Spatial-temporal analysis of coherent offshore wind field structures measured by scanning Doppler-lidar

    Science.gov (United States)

    Valldecabres, L.; Friedrichs, W.; von Bremen, L.; Kühn, M.

    2016-09-01

    An analysis of the spatial and temporal power fluctuations of a simplified wind farm model is conducted on four offshore wind fields data sets, two from lidar measurements and two from LES under unstable and neutral atmospheric conditions. The integral length scales of the horizontal wind speed computed in the streamwise and the cross-stream direction revealed the elongation of the structures in the direction of the mean flow. To analyse the effect of the structures on the power output of a wind turbine, the aggregated equivalent power of two wind turbines with different turbine spacing in the streamwise and cross-stream direction is analysed at different time scales under 10 minutes. The fact of considering the summation of the power of two wind turbines smooths out the fluctuations of the power output of a single wind turbine. This effect, which is stronger with increasing spacing between turbines, can be seen in the aggregation of the power of two wind turbines in the streamwise direction. Due to the anti-correlation of the coherent structures in the cross-stream direction, this smoothing effect is stronger when the aggregated power is computed with two wind turbines aligned orthogonally to the mean flow direction.

  2. Aerodynamic design and analysis of small horizontal axis wind turbine blades

    Science.gov (United States)

    Tang, Xinzi

    This work investigates the aerodynamic design and analysis of small horizontal axis wind turbine blades via the blade element momentum (BEM) based approach and the computational fluid dynamics (CFD) based approach. From this research, it is possible to draw a series of detailed guidelines on small wind turbine blade design and analysis. The research also provides a platform for further comprehensive study using these two approaches. The wake induction corrections and stall corrections of the BEM method were examined through a case study of the NREL/NASA Phase VI wind turbine. A hybrid stall correction model was proposed to analyse wind turbine power performance. The proposed model shows improvement in power prediction for the validation case, compared with the existing stall correction models. The effects of the key rotor parameters of a small wind turbine as well as the blade chord and twist angle distributions on power performance were investigated through two typical wind turbines, i.e. a fixed-pitch variable-speed (FPVS) wind turbine and a fixed-pitch fixed-speed (FPFS) wind turbine. An engineering blade design and analysis code was developed in MATLAB to accommodate aerodynamic design and analysis of the blades.. The linearisation for radial profiles of blade chord and twist angle for the FPFS wind turbine blade design was discussed. Results show that, the proposed linearisation approach leads to reduced manufacturing cost and higher annual energy production (AEP), with minimal effects on the low wind speed performance. Comparative studies of mesh and turbulence models in 2D and 3D CFD modelling were conducted. The CFD predicted lift and drag coefficients of the airfoil S809 were compared with wind tunnel test data and the 3D CFD modelling method of the NREL/NASA Phase VI wind turbine were validated against measurements. Airfoil aerodynamic characterisation and wind turbine power performance as well as 3D flow details were studied. The detailed flow

  3. The analysis of the wind potential in selected locations in the southeastern Poland

    Directory of Open Access Journals (Sweden)

    Sornek Krzysztof

    2017-01-01

    Full Text Available This paper shows the results of analysis of the wind potential in selected locations in the southern Poland (placed in the Małopolskie, Świętokrzyskie and Podkarpackie Voivodships. The measurements and analysis of the wind resources in potential locations of the wind turbines are important part of the investment process. The statistical analysis involves the creation of histograms (e.g. histogram of the wind speed and direction and fitting those histograms to theoretical distributions (e.g. Weilbull distributions of wind speed. Such analysis has been described and conducted using measurement data for four selected locations. Basis on the conducted analysis, the economy efficiency and environmental impact of wind turbine operation has been estimated. Three market available wind turbines have been included to calculate NPV, IRR and SPBT indicators. Then, the avoided emissions of CO2, NOx, SO2 and dust have been calculated. There were also conducted some calculation using TRNSYS simulation software. The results of simulations have been compared with measurement data and the level of convergence have been found.

  4. NORSEWIND – Mesoscale model derived Wind Atlases for the Irish Sea, the North Sea and the Baltic Sea

    DEFF Research Database (Denmark)

    Berge, Erik; Hasager, Charlotte Bay; Bredesen, Rolv Erlend

    2013-01-01

    estimate a random uncertainty of ±4.0 % and a bias of -6.4 % which is higher than for the average annual wind speed. It is emphasized that the amount of validation data is small and considerable spatial variability of the uncertainty may be expected. For example, near coastal zones model errors could...

  5. Offshore wind power economics : analysis on the economic utilization of Turkey's offshore wind power potential under the current support mechanisms

    OpenAIRE

    Ünlü, Mehmet Ali

    2012-01-01

    Climate change and the energy supply security concerns supported the development of wind power growth in the world, which made wind power as one of the fastest growing renewable energy sources. Offshore wind energy attracts more investments day by day with its advantages such as higher wind speeds, larger wind turbines and lower GHG emissions. In order for developing projects that will power the grids with renewable electricity extracted from wind, governments provide extensive policy support...

  6. Implementing wind forecasting at a utility

    Energy Technology Data Exchange (ETDEWEB)

    Landberg, L.; Hansen, M.A.; Vesterager, K.; Bergstroem, W.

    1997-03-01

    This report describes a project - funded by the Danish Ministry of Energy and the Environment - that has as its aim to implement prediction of the power produced by wind farms in the daily planning at the Danish utility ELKRAFT. The predictions are generated from forecasts from HIRLAM (HIgh Resolution Limited Area Model) of the Danish Meteorological Institute. These predictions are then made valid at individual sites (wind farms) by applying either a matrix generated by the sub-models of WA{sup s}P (Wind Atlas Application and Analysis Program) or by use of a Kalman filter. In the project 17 wind farms have been selected for study. The farms are located on the Zealand and Bornholm islands and all belonging to the Danish utility ELKRAFT. (au) 10 tabs., 65 ills., 14 refs.

  7. ATLAS Distributed Computing Automation

    CERN Document Server

    Schovancova, J; The ATLAS collaboration; Borrego, C; Campana, S; Di Girolamo, A; Elmsheuser, J; Hejbal, J; Kouba, T; Legger, F; Magradze, E; Medrano Llamas, R; Negri, G; Rinaldi, L; Sciacca, G; Serfon, C; Van Der Ster, D C

    2012-01-01

    The ATLAS Experiment benefits from computing resources distributed worldwide at more than 100 WLCG sites. The ATLAS Grid sites provide over 100k CPU job slots, over 100 PB of storage space on disk or tape. Monitoring of status of such a complex infrastructure is essential. The ATLAS Grid infrastructure is monitored 24/7 by two teams of shifters distributed world-wide, by the ATLAS Distributed Computing experts, and by site administrators. In this paper we summarize automation efforts performed within the ATLAS Distributed Computing team in order to reduce manpower costs and improve the reliability of the system. Different aspects of the automation process are described: from the ATLAS Grid site topology provided by the ATLAS Grid Information System, via automatic site testing by the HammerCloud, to automatic exclusion from production or analysis activities.

  8. Market analysis offshore wind energy; Marktanalyse Windenergie auf See

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    The North Sea has compared to the Baltic Sea due the available space offering a significantly larger Potential. Compared to the North Sea are the exploitable Potential of the Baltic Sea coast, however, significantly more closer to the coast, which not only for the network connection but also for the construction and operation of plants efficiency benefits may have. It is still unclear whether the available areas of the territorial sea Baltic Sea in relevant scale can be extended. The corresponding Spatial planning process was in 2014 by Mecklenburg- Vorpommern initiated. The analysis of the Federal Offshore Plan fixed Clusters of the offshore grid development plan in structured areas for the North and Baltic Seas (1-5), shows that at least in the expansion phase by 2025, possibly also 2030 the coastally zones 1 and 2 in North and Baltic provide a sufficient surface potential and at the same time with respect to an efficient and structured Network expansion should be developed. The expansion path up to 2020 allows the industry to realize the proposed decreasing trend of cost of over 30 percent. The recognizable today Cost reductions have so far have to take into account in the context of the development the tender design. This also applies to the question of optimal Park and plant designs for the energy industry View. In addition to each project internal difficulties at the network as at wind farm site there are significant interface problems between the wind farm and grid connection. This is, inter alia, due to the different implementation periods after commissioning. An acceleration or flexibilization of the grid connections (in particular DC) would substantially benefit to bring and could lead to a significant improvement of the competitive situation. The competition from sides of the wind turbine manufacturer is currently formed little heterogeneous. On the part of investors, there is in the meantime a relatively high number of potential future Investors which

  9. Analysis of vertical wind direction and speed gradients for data from the met. mast at Hoevsoere

    Energy Technology Data Exchange (ETDEWEB)

    Cariou, N.; Wagner, R.; Gottschall, J.

    2010-05-15

    The task of this project has been to study the vertical gradient of the wind direction from experimental data obtained with different measurement instruments at the Hoevsoere test site, located at the west coast of Denmark. The major part of the study was based on data measured by wind vanes mounted at a meteorological (met.) mast. These measurements enabled us to make an analysis of the variation of the direction with altitude, i.e. the wind direction shear. For this purpose, four years of wind direction measurements at two heights (60 m and 100 m) were analysed with special respect to the diurnal and seasonal variations of the direction gradient. The location of the test site close to the sea allowed for an investigation of specific trends for offshore and onshore winds, dependent on the considered wind direction sector. Furthermore, a comparison to lidar measurements showed the existence of an offset between the two vanes used for the analysis, which has to be considered for evaluating the significance and uncertainty of the results. Finally, the direction shear was analysed as function of wind speed and compared to the corresponding relation for the wind speed shear. Our observation from this is that the direction shear does not necessarily increase with the speed shear. (author)

  10. Analysis and Comparison of Test Results from the Small Wind Research Turbine Test Project: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Corbus, D.; Prascher, D.

    2004-11-01

    Most small wind turbines furl (yaw or tilt out of the wind) as a means of limiting power and rotor speeds in high winds. The Small Wind Research Turbine (SWRT) testing project was initiated in 2003 with the goal of better characterizing both small wind turbine loads (including thrust) and dynamic behavior, specifically as they relate to furling. The main purpose of the testing was to produce high-quality data sets for model development and validation and to help the wind industry further their understanding of small wind turbine behavior. Testing was conducted on a modified Bergey Excel 10-kW wind turbine. A special shaft sensor was designed to measure shaft loads including thrust, torque, and shaft bending. Analysis of 10-minute mean data showed a strong correlation between furling and center of thrust location, as calculated from the shaft-bending and thrust measurements. Data were collected for three different turbine configurations that included a change in the lateral furling offset and the blades. An analysis of inflow conditions indicated that organized atmospheric turbulence had some impact on furling.

  11. Free wake analysis of wind turbine aerodynamics. Wind energy conversion. ASRL-TR-184-14

    Energy Technology Data Exchange (ETDEWEB)

    Gohard, J.C.

    1978-09-01

    The underlying theory is presented for determining blade and rotor/tower vibration and dynamic stability characteristics as well as the basic dynamic (as opposed to aerodynamic) operating loads. Starting with a simple concept of equivalent hinged rotors, the equations of motion for the blade including pitch, flap and lag motions are developed. The nonlinear equations are derived first and linearized about a finite displacement of the blade out of the plane of rotation. This is important since wind turbines tend to operate at relatively high coning angles. The effect of distributed flexibility, as opposed to the equivalent hinge concept, is then discussed.

  12. Western Wind and Solar Integration Study: Hydropower Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Acker, T.; Pete, C.

    2012-03-01

    The U.S. Department of Energy's (DOE) study of 20% Wind Energy by 2030 was conducted to consider the benefits, challenges, and costs associated with sourcing 20% of U.S. energy consumption from wind power by 2030. This study found that with proactive measures, no insurmountable barriers were identified to meet the 20% goal. Following this study, DOE and the National Renewable Energy Laboratory (NREL) conducted two more studies: the Eastern Wind Integration and Transmission Study (EWITS) covering the eastern portion of the U.S., and the Western Wind and Solar Integration Study (WWSIS) covering the western portion of the United States. The WWSIS was conducted by NREL and research partner General Electric (GE) in order to provide insight into the costs, technical or physical barriers, and operational impacts caused by the variability and uncertainty of wind, photovoltaic, and concentrated solar power when employed to serve up to 35% of the load energy in the WestConnect region (Arizona, Colorado, Nevada, New Mexico, and Wyoming). WestConnect is composed of several utility companies working collaboratively to assess stakeholder and market needs to and develop cost-effective improvements to the western wholesale electricity market. Participants include the Arizona Public Service, El Paso Electric Company, NV Energy, Public Service of New Mexico, Salt River Project, Tri-State Generation and Transmission Cooperative, Tucson Electric Power, Xcel Energy and the Western Area Power Administration.

  13. Statistical Analysis and Comparison of Harmonics Measured in Offshore Wind Farms

    DEFF Research Database (Denmark)

    Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth

    2011-01-01

    The paper shows statistical analysis of harmonic components measured in different offshore wind farms. Harmonic analysis is a complex task and requires many aspects, such as measurements, data processing, modeling, validation, to be taken into consideration. The paper describes measurement process...... and shows sophisticated analysis on representative harmonic measurements from Avedøre Holme, Gunfleet Sands and Burbo Bank wind farms. The nature of generation and behavior of harmonic components in offshore wind farms clearly presented and explained based on probabilistic approach. Some issues regarding...... commonly applied standards are also put forward in the discussion. Based on measurements and data analysis it is shown that a general overview about wind farm harmonic behaviour cannot be fully observed only based on single-value measurements as suggested in the standards but using more descriptive...

  14. Analysis and control of the vibration of doubly fed wind turbine

    Science.gov (United States)

    Yu, Manye; Lin, Ying

    2017-01-01

    The fault phenomena of the violent vibration of certain doubly-fed wind turbine were researched comprehensively, and the dynamic characteristics, load and fault conditions of the system were discussed. Firstly, the structural dynamics analysis of wind turbine is made, and the dynamics mold is built. Secondly, the vibration testing of wind turbine is done with the German test and analysis systems BBM. Thirdly, signal should be analyzed and dealt with. Based on the experiment, spectrum analysis of the motor dynamic balance can be made by using signal processing toolbox of MATLAB software, and the analysis conclusions show that the vibration of wind turbine is caused by dynamic imbalance. The results show that integrating mechanical system dynamics theory with advanced test technology can solve the vibration problem more successfully, which is important in vibration diagnosis of mechanical equipment.

  15. Loads Analysis of a Floating Offshore Wind Turbine Using Fully Coupled Simulation: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jonkman, J. M.; Buhl, M. L., Jr.

    2007-06-01

    This paper presents the use of fully coupled aero-hydro-servo-elastic simulation tools to perform a loads analysis of a 5-MW offshore wind turbine supported by a barge with moorings, one of many promising floating platform concepts.

  16. High-Freqeuncy Analysis of Three-Winding Autotransformers 400/121/34 kV

    Directory of Open Access Journals (Sweden)

    Miroslav Gutten

    2008-01-01

    Full Text Available This article deals with a description of methods of an experimental analysis concerning the actual condition of windings and magnetic circuit of the autotransformer, which is required in power transmission companies all over the world.

  17. Accuracy of an efficient framework for structural analysis of wind turbine blades

    DEFF Research Database (Denmark)

    Blasques, José Pedro Albergaria Amaral; Bitsche, Robert D.; Fedorov, Vladimir

    2016-01-01

    -section analysis tool is able to capture the effects stemming from material anisotropy and inhomogeneity for sections of arbitrary geometry. The proposed framework is very efficient and therefore ideally suited for integration within wind turbine aeroelastic design and analysis tools. A number of benchmark......This paper presents a novel framework for the structural design and analysis of wind turbine blades and establishes its accuracy. The framework is based on a beam model composed of two parts—a 2D finite element-based cross-section analysis tool and a 3D beam finite element model. The cross...... examples are presented comparing the results from the proposed beam model to 3D shell and solid finite element models. The examples considered include a square prismatic beam, an entire wind turbine rotor blade and a detailed wind turbine blade cross section. Phenomena at both the blade length scale...

  18. Wind power resource in the south-western region of Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Himri, Y. [Electricity and Gas National Enterprise (SONELGAZ), Bechar (Algeria); University of Sciences and Technology of Oran, Department of Electronic, Oran (Algeria); Himri, S. [University of Bechar, Department of fundamental Sciences, Bechar (Algeria); Laboratory Signal IMage Parole (SIMPA), Department of Computing Science, Oran (Algeria); Stambouli, A. Boudghene [University of Sciences and Technology of Oran, Department of Electronic, Oran (Algeria)

    2010-01-15

    In this study, we present a statistical analysis of wind speeds at Tindouf in Algeria using Risoe National Laboratory's Wind Atlas Analysis and Application Program (WAsP). It requires information related to the sheltering obstacles, surface roughness changes and terrain height variations in order to calculate their effects on the wind. Wind data, consisting of hourly wind speed records over a 5-year period, 2002-2006, were obtained from SONELGAZ R and D Office; the average wind speed at a height of 17 m above ground level was found to range from 7.19 to 7.95 m/s. The Weibull distributions parameters (c and k) were found to vary between 8.0 and 8.9 m/s and 2.54-3.23, respectively, with average power density ranging from 318 to 458 W/m{sup 2}. The dominant wind directions and the frequency distributions were also determined. (author)

  19. OW CCMP Ocean Surface Wind

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Cross-Calibrated Multi-Platform (CCMP) Ocean Surface Wind Vector Analyses (Atlas et al., 2011) provide a consistent, gap-free long-term time-series of monthly...

  20. CFD and Wind Tunnel Analysis for Mounted-Wind Turbine in a Tall Building for Power Generation

    Directory of Open Access Journals (Sweden)

    Dany Perwita Sari

    2014-07-01

    Full Text Available A mounted wind turbine on the top of a tall building may provide high wind power in regions of high wind speed and low turbulence. The objective of this study is to evaluate wind speed on roof top models to optimize the wind turbine performance for power generation. Comparative analyses from three different roof top models were conducted. Computational Fluid Dynamics (CFD simulation and wind tunnel testing were performed to evaluate the performance of wind turbine. Wind speed on the building model with a geometric scale of 1:150 was measured in CFD simulation then it was validated in wind tunnel test. Results presented in this paper suggest that an increase of wind speed could be achieved with ¼ circular shapes around the rooftop which can provide additional wind speed of 55.24%, respectively.

  1. Modal analysis of a small vertical axis wind turbine (Type DARRIEUS

    Directory of Open Access Journals (Sweden)

    Ion NILA

    2012-06-01

    Full Text Available This paper reports a brief study on free vibration analysis for determining parameters such as natural frequencies and mode shapes for vertical axis wind turbines (VAWT for an urban application. This study is focused on numerical work using available finite element software. For further understanding of the wind turbine dynamic analysis, two vibration parameters of dynamic response have been studied, namely natural frequencies and mode shapes.Block Lanczos method has been used to analyze the natural frequency while wind turbine mode shapes have been utilized because of their accuracy and faster solution. In this problem 12 modes of structure have been extracted.

  2. Power train analysis for the DOE/NASA 100-kW wind turbine generator

    Science.gov (United States)

    Seidel, R. C.; Gold, H.; Wenzel, L. M.

    1978-01-01

    Progress in explaining variations of power experienced in the on-line operation of a 100 kW experimental wind turbine-generator is reported. Data are presented that show the oscillations tend to be characteristic of a wind-driven synchronous generator because of low torsional damping in the power train, resonances of its large structure, and excitation by unsteady and nonuniform wind flow. The report includes dynamic analysis of the drive-train torsion, the generator, passive driveline damping, and active pitch control as well as correlation with experimental recordings. The analysis assumes one machine on an infinite bus with constant generator-field excitation.

  3. Integration of ROOT Notebooks as a Web-based ATLAS Analysis tool for public data releases and outreach

    CERN Document Server

    Banda, Tea; CERN. Geneva. EP Department

    2016-01-01

    The project consists in the initial development of ROOT notebooks for a Z boson analysis in C++ programming language that will allow students and researches to perform fast and very useful data analysis, using ATLAS public data and Monte- Carlo simulations. Several tools are considered: ROOT Data Analysis Frame- work, Jupyter Notebook Technology and CERN-ROOT computing service so-called SWAN.

  4. Dynamic Analysis of Wind Turbines Including Soil-Structure Interaction

    DEFF Research Database (Denmark)

    Harte, M.; Basu, B.; Nielsen, Søren R.K.

    2012-01-01

    blades and includes the effect of centrifugal stiffening due to rotation. The foundation of the structure is modeled as a rigid gravity based foundation with two DOF whose movement is related to the surrounding soil by means of complex impedance functions generated using cone model. Transfer functions...... for displacement of the turbine system are obtained and the modal frequencies of the combined turbine-foundation system are estimated. Simulations are presented for the MDOF turbine structure subjected to wind loading for different soil stiffness conditions. Steady state and turbulent wind loading, developed using...... blade element momentum theory and the Kaimal spectrum, have been considered. Soil stiffness and damping properties acquired from DNV/Risø standards are used as a comparison. The soil-structure interaction is shown to affect the response of the wind turbine. This is examined in terms of the turbine...

  5. Slotted Blades Savonius Wind Turbine Analysis by CFD

    Directory of Open Access Journals (Sweden)

    Andrea Alaimo

    2013-12-01

    Full Text Available In this paper a new bucket configuration for a Savonius wind generator is proposed. Numerical analyses are performed to estimate the performances of the proposed configuration by means of the commercial code COMSOL Multiphysics® with respect to Savonius wind turbine with overlap only. Parametric analyses are performed, for a fixed overlap ratio, by varying the slot position; the results show that for slot positioned near the blade root, the Savonius rotor improves performances at low tip speed ratio, evidencing a better starting torque. This circumstance is confirmed by static analyses performed on the slotted blades in order to investigate the starting characteristic of the proposed Savonius wind generator configuration.

  6. Qualitative analysis of wind-turbine wakes over hilly terrain

    Science.gov (United States)

    Hyvärinen, A.; Segalini, A.

    2017-05-01

    In this work, wind-turbine wakes are studied over flat and hilly terrains. Measurements made by using stereoscopic PIV are compared to data obtained from numerical simulations using RANS equations and an actuator-disc method. The numerical and experimental data show similar qualitative trends, indicating that the wind-turbine wake is perturbed by the presence of the hills. Additionally, a faster flow recovery at hub height is seen with the hilly terrain, indicating that the hills presence is beneficial for downstream turbines exposed to wake-interaction effects. The Jensen wake model is implemented over the hilly terrain and it is shown that this model cannot accurately capture the wake modulations induced by the hills. However, by superimposing a wind-turbine wake simulated over flat terrain on the hilly-terrain flow field, it is illustrated that the commonly-used wake-superposition technique can yield reasonable results if the used wake model has sufficient accuracy.

  7. Flow Field Analysis of Wind Power Generation System

    Science.gov (United States)

    Zhou, Chao; Huang, Wei; Zhu, Daohua; Li, Yan; Wu, Liwei

    2017-10-01

    The purpose is to solve the problem of wind power curtailment in the wind power generation system. A new type of wind power generation system made of flexible blades is proposed. Combined with the experimental method and numerical simulation method, the impeller blades are analyzed by flow field. The values of the lift coefficient of the leaves under different working conditions were obtained and analyzed. The optimum curvature and the range of the best angle of attack are determined. The influence of the parameters such as the curvature of the blade and the angle of attack on the hydrodynamic performance of the blade and impeller in the power generation system is obtained. The results showed that the best curvature K was 0.019 and the best angle of attack was 20°. Therefore, it can be concluded that it reveals the influence of blade curvature and angle of attack on the lift coefficient.

  8. Integration of ROOT Notebooks as a Web-based ATLAS Analysis tool for Public Data Releases and Outreach

    CERN Document Server

    Abah, Anthony

    2016-01-01

    The project worked on the development of a physics analysis and its software under ROOT framework and Jupyter notebooks for the the ATLAS Outreach and the Naples teams. This analysis is created in the context of the release of data and Monte Carlo samples by the ATLAS collaboration. The project focuses on the enhancement of the recent opendata.atlas.cern web platform to be used as educational resources for university students and new researches. The generated analysis structure and tutorials will be used to extend the participation of students from other locations around the World. We conclude the project with the creation of a complete notebook representing the so-called W analysis in C + + language for the mentioned platform.

  9. Performance Analysis of a Hybrid Generation System of Wind Turbines, Photovoltaic Modules, and a Fuel Cell

    Directory of Open Access Journals (Sweden)

    Bartosz Ceran

    2015-06-01

    Full Text Available This paper presents the results of energy analysis of a generation system consisting of wind turbines, photovoltaic modules, a fuel cell with a polymer membrane, and an electrolyser. The analysis was carried out for three configurations of generating devices’ connections with consumer: I – wind turbines and photovoltaic modules supply electrolyser, II – paralel co-operation of fuel cell with renewables, III – renewables supply electrolyser, with the option of direct supply of the consumer.

  10. Performance Analysis of a Hybrid Generation System of Wind Turbines, Photovoltaic Modules, and a Fuel Cell

    OpenAIRE

    Bartosz Ceran; Krzysztof Sroka

    2015-01-01

    This paper presents the results of energy analysis of a generation system consisting of wind turbines, photovoltaic modules, a fuel cell with a polymer membrane, and an electrolyser. The analysis was carried out for three configurations of generating devices’ connections with consumer: I – wind turbines and photovoltaic modules supply electrolyser, II – paralel co-operation of fuel cell with renewables, III – renewables supply electrolyser, with the option of direct supply of the consumer....

  11. Analysis of a commercial wind farm in Taiwan

    DEFF Research Database (Denmark)

    Wang, Li; Yeh, Tai-Her; Lee, Wei-Jen

    2010-01-01

    This paper presents both steady-state performance and dynamic simulations of a commercial wind farm (WF) in Taiwan through field measurement results and computer simulations. The companion paper in Part II discusses the dynamic and transient analyzed results of using current-limit reactors (CLRs......) and load tap changers on power-quality improvement of the studied WF. With 23 2-MW DFIG-type wind turbine generators, this WF is connected to the 161-kV extra high-voltage substation of Taiwan Power System through a 23/161-kV 60-MVA step-up main transformer from six feeders with CLRs. Through comparing...

  12. Analysis of turbulent wake behind a wind turbine

    DEFF Research Database (Denmark)

    Kermani, Nasrin Arjomand; Andersen, Søren Juhl; Sørensen, Jens Nørkær

    2013-01-01

    and momentum conservations, the selfsimilarity of mean velocity profile and the eddy viscosity closure. The theoretical approach is validated using the numerical results obtained from large eddy simulations with an actuator line technique at 0.1% and 3% ambient turbulence level and ambient wind velocity of 10...... m/s, and 0.1% ambient turbulence level and ambient wind velocity of 7 m/s. The obtained results showed that neglecting the nonlinear term of velocity in the momentum equation in the far wake region cannot be a fair assumption, unlike what is generally assumed in most of text books of fluid mechanics...

  13. AWSM. Ground and wind shear effects in aerodynamic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, F. [ECN Wind Energy, Petten (Netherlands)

    2010-02-15

    In order to design more advanced and efficient wind turbines, more accurate results coming from numerical predictions are mandatory. This need became more and more important in the last years due to the growth of wind turbines, especially for offshore scenarios. The diameter of a modern MW class wind turbine can easily be greater than 100m, on which the effect of wind shear and incoherent atmospheric structures on blade loads play a much more significant role. Most of the available codes are based on Blade Element Momentum (BEM) theory. The main advantage of this class of codes is the fact that they are very fast to calculate the loads and performance of a wind turbine. This makes BEM codes very convenient especially in the very extensive wind turbine design and load calculations, but due to all the hypotheses of the theory, there are several restrictions for BEM codes usage. By using full Navier-Stokes based codes, for example, there are no limitations about the geometry and no restrictive hypotheses related with the aerodynamics, so it is possible to perform both detailed fluid-dynamics studies and general performance-oriented analyses in very general conditions. The drawback is the big demand in terms of computational resources, computational time and expertise. A code, named Aerodynamic Windturbine Simulation Module (AWSM), has been developed at Energy research Centre of the Netherlands (ECN). The main scope was to keep the advantages of BEM codes in terms of calculation time and ease of use, but to obtain a superior quality, especially concerning wake and time dependent wake-related phenomena. The presence of the ground during the analyses, as well as the presence of a nonuniform wind introduce sensitive effects in the numerical predictions. These effects regard both the response of the blade and the evolution of the wake. During UpWind project, part of the research was focused on these two effects and their inclusion in the calculations. The aim of the

  14. An analysis of low frequency noise from large wind turbines

    DEFF Research Database (Denmark)

    Pedersen, Christian Sejer; Møller, Henrik

    2010-01-01

    As wind turbines get larger, worries have emerged, that the noise emitted by the turbines would move down in frequency, and that the contents of low-frequency noise would be enough to cause significant annoyance for the neighbors. The sound emission from 48 wind turbines with nominal electric power......-third-octave-band spectra shows that the relative noise emission is higher in the 63-250 Hz frequency range from turbines above 2 MW than from smaller turbines. The observations confirm a downward shift of the spectrum....

  15. Analysis of powerful local acceleration of solar wind particles

    Science.gov (United States)

    Molotkov, I. A.; Ryabova, N. A.

    2017-07-01

    Collisionless plasma of the solar wind is considered. A number of physical processes in this plasma lead to the formation of magnetic islands that are potential traps for charged particles. The merging and contractions of magnetic islands cause a powerful acceleration of these particles to energies over 1 MeV. This work continues the study in recent years on modeling of the acceleration of charged particles of the solar wind. Our analytical solution of the transport equations allowed us to find the exact number of particles with energies exceeding given level.

  16. Wind resource estimation and siting of wind turbines

    DEFF Research Database (Denmark)

    Lundtang Petersen, Erik; Mortensen, N.G.; Landberg, L.

    1994-01-01

    Detailed knowledge of the characteristics of the natural wind is necessary for the design, planning and operational aspect of wind energy systems. Here, we shall only be concerned with those meteorological aspects of wind energy planning that are termed wind resource estimation. The estimation...... of the wind resource ranges from the overall estimation of the mean energy content of the wind over a large area - called regional assessment - to the prediction of the average yearly energy production of a specific wind turbine at a specific location - called siting. A regional assessment will most often...... lead to a so-called wind atlas. A precise prediction of the wind speed at a given site is essential because for aerodynamic reasons the power output of a wind turbine is proportional to the third power of the wind speed, hence even small errors in prediction of wind speed may result in large deviations...

  17. Condition monitoring of a wind turbine doubly-fed induction generator through current signature analysis

    Science.gov (United States)

    Artigao, Estefania; Honrubia-Escribano, Andres; Gomez-Lazaro, Emilio

    2017-11-01

    Operation and maintenance (O&M) of wind turbines is recently becoming the spotlight in the wind energy sector. While wind turbine power capacities continue to increase and new offshore developments are being installed, O&M costs keep raising. With the objective of reducing such costs, the new trends are moving from corrective and preventive maintenance toward predictive actions. In this scenario, condition monitoring (CM) has been identified as the key to achieve this goal. The induction generator of a wind turbine is a major contributor to failure rates and downtime where doubly-fed induction generators (DFIG) are the dominant technology employed in variable speed wind turbines. The current work presents the analysis of an in-service DFIG. A one-year measurement campaign has been used to perform the study. Several signal processing techniques have been applied and the optimal method for CM has been identified. A diagnosis has been reached, the DFIG under study shows potential gearbox damage.

  18. Analysis of Transient Phenomena Due to a Direct Lightning Strike on a Wind Energy System

    Directory of Open Access Journals (Sweden)

    João P. S. Catalão

    2012-07-01

    Full Text Available This paper is concerned with the protection of wind energy systems against the direct effects of lightning. As wind power generation undergoes rapid growth, lightning damages involving wind turbines have come to be regarded as a serious problem. Nevertheless, very few studies exist yet in Portugal regarding lightning protection of wind energy systems using numerical codes. A new case study is presented in this paper, based on a wind turbine with an interconnecting transformer, for the analysis of transient phenomena due to a direct lightning strike to the blade. Comprehensive simulation results are provided by using models of the Restructured Version of the Electro-Magnetic Transients Program (EMTP, and conclusions are duly drawn.

  19. Harmonic Active Filtering and Impedance-based Stability Analysis in Offshore Wind Power Plants

    DEFF Research Database (Denmark)

    Dhua, Debasish; Yang, Guangya; Zhang, Zhe

    2017-01-01

    installation and provides effectively similar functionality as passive filters. This work is focused on harmonic propagation studies in wind power plants, power quality evaluation at the point of connection and harmonic mitigation by active filtering. Finally, an impedance-based stability analysis......Nowadays, to eliminate harmonics injected by the wind turbines in offshore wind power plants there is a need to install passive filters. Moreover, the passive filters are not adaptive to harmonic profile changes due to topology changes, grid loading etc. Therefore, active filters in wind turbines...... are proposed as a flexible harmonic mitigation measure. The motivation of this study is to explore the possibility of embedding active filtering in wind turbine grid-side converters without having to change the system electrical infrastructure. The active filtering method can prevent additional equipment...

  20. Dashboard Task Monitor for managing ATLAS user analysis on the Grid

    CERN Document Server

    Sargsyan, L; Jha, M; Karavakis, E; Kokoszkiewicz, L; Saiz, P; Schovancova, J; Tuckett, D

    2014-01-01

    The organization of the distributed user analysis on the Worldwide LHC Computing Grid (WLCG) infrastructure is one of the most challenging tasks among the computing activities at the Large Hadron Collider. The Experiment Dashboard offers a solution that not only monitors but also manages (kill, resubmit) user tasks and jobs via a web interface. The ATLAS Dashboard Task Monitor provides analysis users with a tool that is independent of the operating system and GRID environment . This contribution describes the functionality of the application and its implementation details, in particular authentication, authorization and audit of the management operations.

  1. Dashboard Task Monitor for managing ATLAS user analysis on the Grid

    CERN Document Server

    Sargsyan, L; The ATLAS collaboration; Jha, M; Karavakis, E; Kokoszkiewicz, L; Saiz, P; Schovancova, J; Tuckett, D

    2013-01-01

    The organization of the distributed user analysis on the Worldwide LHC Computing Grid (WLCG) infrastructure is one of the most challenging tasks among the computing activities at the Large Hadron Collider. The Experiment Dashboard offers a solution that not only monitors but also manages (kill, resubmit) user tasks and jobs via a web interface. The ATLAS Dashboard Task Monitor provides analysis users with a tool that is operating system and GRID environment independent. This contribution describes the functionality of the application and its implementation details, in particular authentication, authorization and audit of the management operations.

  2. Analysis of environmental dispersion in a wetland flow under the effect of wind: Extended solution

    Science.gov (United States)

    Wang, Huilin; Huai, Wenxin

    2018-02-01

    The accurate analysis of the contaminant transport process in wetland flows is essential for environmental assessment. However, dispersivity assessment becomes complicated when the wind strength and direction are taken into consideration. Prior studies illustrating the wind effect on environmental dispersion in wetland flows simply focused on the mean longitudinal concentration distribution. Moreover, the results obtained by these analyses are not accurate when done on a smaller scale, namely, the initial stage of the contaminant transport process. By combining the concentration moments method (the Aris' method) and Gill's expansion theory, the previous researches on environmental dispersion in wetland flows with effect of wind have been extended. By adopting up to 4th-order moments, the wind effect-as illustrated by dimensionless parameters Er (wind force) and ω (wind direction)-on kurtosis and skewness is discussed, the up to 4th-order vertical concentration distribution is obtained, and the two-dimensional concentration distribution is illustrated. This work demonstrates that wind intensity and direction can significantly affect the contaminant dispersion. Moreover, the study presents a more accurate analytical solution of environmental dispersion in wetland flows under various wind conditions.

  3. Stress analysis of composite wind turbine blade by finite element method

    Science.gov (United States)

    Yeh, Meng-Kao; Wang, Chen-Hsu

    2017-10-01

    In this study, the finite element analysis software ANSYS was used to analyze the composite wind turbine blade. The wind turbine blade model used is adopted from the 5 MW model of US National Renewable Energy Laboratory (NREL). The wind turbine blade is a sandwich structure, comprising outermost carbon fiber cloth/epoxy composites, the inner glass fiber/vinylester layers, and PVC foam core, together with stiffeners. The wind pressure is converted into the load on the blade structure. The stress distribution and deformation of wind turbine blade were obtained by considering different pitch angles and at different angular positions. The Tsai-Hill criterion was used to determine the failure of wind turbine blade. The results show that at the 0° pitch angle, the wind turbine blade is subjected to the largest combined load and therefore the stress is the largest; with the increasing pitch angle, the load gradually decreases and the stress is also smaller. The stress and displacement are the greatest when the wind blade is located at 120° angular position from its highest vertex.

  4. Static Aeroelastic Scaling and Analysis of a Sub-Scale Flexible Wing Wind Tunnel Model

    Science.gov (United States)

    Ting, Eric; Lebofsky, Sonia; Nguyen, Nhan; Trinh, Khanh

    2014-01-01

    This paper presents an approach to the development of a scaled wind tunnel model for static aeroelastic similarity with a full-scale wing model. The full-scale aircraft model is based on the NASA Generic Transport Model (GTM) with flexible wing structures referred to as the Elastically Shaped Aircraft Concept (ESAC). The baseline stiffness of the ESAC wing represents a conventionally stiff wing model. Static aeroelastic scaling is conducted on the stiff wing configuration to develop the wind tunnel model, but additional tailoring is also conducted such that the wind tunnel model achieves a 10% wing tip deflection at the wind tunnel test condition. An aeroelastic scaling procedure and analysis is conducted, and a sub-scale flexible wind tunnel model based on the full-scale's undeformed jig-shape is developed. Optimization of the flexible wind tunnel model's undeflected twist along the span, or pre-twist or wash-out, is then conducted for the design test condition. The resulting wind tunnel model is an aeroelastic model designed for the wind tunnel test condition.

  5. Structural analysis of wind turbine rotors for NSF-NASA Mod-0 wind power system

    Science.gov (United States)

    Spera, D. A.

    1976-01-01

    Preliminary estimates are presented of vibratory loads and stresses in hingeless and teetering rotors for the proposed NSF-NASA Mod-0 wind power system. Preliminary blade design utilizes a tapered tubular aluminum spar which supports nonstructural aluminum ribs and skin and is joined to the rotor hub by a steel shank tube. Stresses in the shank of the blade are calculated for static, rated, and overload operating conditions. Blade vibrations were limited to the fundamental flapping modes, which were elastic cantilever bending for hingeless rotor blades and rigid-body rotation for teetering rotor blades. The MOSTAB-C computer code was used to calculate aerodynamic and mechanical loads. The teetering rotor has substantial advantages over the hingeless rotor with respect to shank stresses, fatigue life, and tower loading. The hingeless rotor analyzed does not appear to be structurally stable during overloads.

  6. Analysis of a commercial wind farm in Taiwan

    DEFF Research Database (Denmark)

    Wang, Li; Yeh, Tai-Her; Lee, Wei-Jen

    2010-01-01

    , and simulation results of the studied Jang-Bin wind farm with 23 2-MW doubly fed induction generator-type wind turbine generators connected to the utility system through a 23/161-kV 60-MVA step-up main transformer (MT) from six feeders. Six CLRs, which were originally designed to limit short-circuit currents......This paper presents the effects of installing variable current-limit reactors (CLRs) and adjusting load tap changers (LTCs) on the performance of a commercial wind farm in Taiwan using computer simulations. The companion paper (Part I) demonstrates the field-measured results, simulation model...... under faulted conditions, are connected in series with the six feeders. The LTCs of the MT are used to adjust/regulate the secondary-side voltage at the 23-kV bus. Some simulated steady-state and transient results of the studied wind farm with variable values of the proposed CLRs and LTCs are analyzed...

  7. Analysis of Ion Charge States in Solar Wind and CMEs

    Indian Academy of Sciences (India)

    We discuss needs in dielectronic recombination data motivated by recent work directed at a quantitative understanding of ion charge states of various elements observed in situ in the solar wind and CMEs. The competing processes of ionization and recombination lead to departures from collision ionization equilibrium.

  8. 3D CFD Analysis of a Vertical Axis Wind Turbine

    Directory of Open Access Journals (Sweden)

    Andrea Alaimo

    2015-04-01

    Full Text Available To analyze the complex and unsteady aerodynamic flow associated with wind turbine functioning, computational fluid dynamics (CFD is an attractive and powerful method. In this work, the influence of different numerical aspects on the accuracy of simulating a rotating wind turbine is studied. In particular, the effects of mesh size and structure, time step and rotational velocity have been taken into account for simulation of different wind turbine geometries. The applicative goal of this study is the comparison of the performance between a straight blade vertical axis wind turbine and a helical blade one. Analyses are carried out through the use of computational fluid dynamic ANSYS® Fluent® software, solving the Reynolds averaged Navier–Stokes (RANS equations. At first, two-dimensional simulations are used in a preliminary setup of the numerical procedure and to compute approximated performance parameters, namely the torque, power, lift and drag coefficients. Then, three-dimensional simulations are carried out with the aim of an accurate determination of the differences in the complex aerodynamic flow associated with the straight and the helical blade turbines. Static and dynamic results are then reported for different values of rotational speed.

  9. determination of weibull parameters and analysis of wind power

    African Journals Online (AJOL)

    HOD

    abundant renewable energy sources. For instance, a study on sustainably meeting the energy needs of. Nigeria: the renewable energy option was carried out by. [6] and the conclusion was that Nigeria was sustainably rich and ought not to be lacking power. Regarding the country's wind energy potential and its viability for.

  10. Design and analysis of full pitch winding and concentrated stator ...

    Indian Academy of Sciences (India)

    The flux reversal machine (FRM) is a doubly-salient stator permanent magnet machine with flux linkage reversal in the stator concentrated winding. The existing machines at low speed, low power (2·4 kW, 300 rpm) range are not economical. FRM topology is best suited for this application. An attempt has been made to ...

  11. Analysis of North Sea Offshore Wind Power Variability

    Directory of Open Access Journals (Sweden)

    Aymeric Buatois

    2014-05-01

    Full Text Available This paper evaluates, for a 2030 scenario, the impact on onshore power systems in terms of the variability of the power generated by 81 GW of offshore wind farms installed in the North Sea. Meso-scale reanalysis data are used as input for computing the hourly power production for offshore wind farms, and this total production is analyzed to identify the largest aggregated hourly power variations. Based on publicly available information, a simplified representation of the coastal power grid is built for the countries bordering the North Sea. Wind farms less than 60 km from shore are connected radially to the mainland, while the rest are connected to a hypothetical offshore HVDC (High-Voltage Direct Current power grid, designed such that wind curtailment does not exceed 1% of production. Loads and conventional power plants by technology and associated cost curves are computed for the various national power systems, based on 2030 projections. Using the MATLAB-based MATPOWER toolbox, the hourly optimal power flow for this regional hybrid AC/DC grid is computed for high, low and medium years from the meso-scale database. The largest net load variations are evaluated per market area and related to the extra load-following reserves that may be needed from conventional generators.

  12. An aeroelastic analysis of the Darrieus wind turbine

    Science.gov (United States)

    Meyer, E. E.; Smith, C. E.

    1983-12-01

    The stability of a single Darrieus wind turbine blade spinning in still air is investigated using linearized equations of motion. The three most dangerous flutter modes are characterized for a one-parameter family of blades. In addition, the influence of blade density, mass and aerodynamic center offsets, and structural damping is presented.

  13. Wind-driven marine phytoplank blooms: Satellite observation and analysis

    Science.gov (United States)

    Tang, DanLing

    2016-07-01

    Algal bloom is defined as a rapid increase or accumulation in biomass in an aquatic system. It not only can increase the primary production but also could result in negative ecological consequence, e.g.,Harmful Algal Blooms (HABs). According to the classic theory for the formation of algal blooms "critical depth" and "eutrophication", oligotrophic sea area is usually difficult to form a large area of algal blooms, and actuallythe traditional observation is only sporadic capture to the existence of algal blooms.Taking full advantage of multiple data of satellite remote sensing , this study introduces "Wind-driven algal blooms in open oceans: observation and mechanisms" It explained except classic coastal Ekman transport, the wind through a variety of mechanisms affecting the formation of algal blooms. Proposed a conceptual model of "Strong wind -upwelling-nutrient-phytoplankton blooms" in Western South China Sea (SCS) to assess role of wind-induced advection transport in phytoplankton bloom formation. It illustrates the nutrient resources that support long-term offshore phytoplankton blooms in the western SCS; (2)Proposal of the theory that "typhoons cause vertical mixing, induce phytoplankton blooms", and quantify their important contribution to marine primary production; Proposal a new ecological index for typhoon. Proposed remote sensing inversion models. (3)Finding of the spatial and temporaldistributions pattern of harmful algal bloom (HAB)and species variations of HAB in the South Yellow Sea and East China Sea, and in the Pearl River estuary, and their oceanic dynamic mechanisms related with monsoon; The project developed new techniques and generated new knowledge, which significantly improved understanding of the formation mechanisms of algal blooms. The proposed "wind-pump" mechanism integrates theoretical system combined "ocean dynamics, development of algal blooms, and impact on primary production", which will benefit fisheries management. These

  14. Introducing log-kappa distributions for solar wind analysis

    Science.gov (United States)

    Leitner, Martin; Vörös, Zolan Z.; Leubner, Manfred P.

    2010-05-01

    The one-point probability density functions (PDFs) obtained from the Wind spacecraft observations of the magnitude of total magnetic field (B) and the solar wind quasi-invariant (QI) are investigated at 1 AU during the years 1995 and 1998. It is known from previous studies that the distributions follow in a rather good approximation a lognormal distribution. This indicates that the underlying random multiplicative processes are skewed, the PDFs are nonsymmetric. The concept of kappa distributions generating PDF tails closer to the observed values is introduced. The skewness, characteristic for the multiplicative processes in the solar wind, is treated on the basis of log-kappa distributions, introduced here for the first time. Normal and lognormal distributions are related in a similar way to each other as the kappa and log-kappa distributions, although the statistics is based on extensive physics in the former and nonextensive physics in the latter cases. We show hat log-kappa PDFs describe the observed distributions in the solar wind more accurately than the lognormal PDFs. In particular, the tails of PDFs corresponding to extreme values of the considered parameters B and QI are better modeled in terms of the nonextensive approach. It indicates that, for the theoretical explanation of the complexity of multisource fluctuations present in 1 year solar wind magnetic and plasma data, both the extensive and the nonextensive physical escription is needed. The variation of the values of kappa obtained from the log-kappa fits can serve as a quantitative measure describing the changing balance between these two distinct physical processes during the solar cycle.

  15. The E-Region Wind Interferometer (ERWIN): Description of the Least Mean Squares Data Analysis Routine, Wind Results, and Comparisons with the Meteor Radar

    Science.gov (United States)

    Kristoffersen, Samuel Kaare

    The E-Region Wind Interferometer (ERWIN) is a Michelson interferometer which observes mesospheric winds using Doppler shifts in three airglow emissions (atomic oxygen, molecular oxygen, and hydroxyl). Innovations include a quad mirror and a CCD detector which allow simultaneous observation of winds in four directions and the vertical. A measurement cadence of ~ 3 minutes for all the airglow emissions and directions with an accuracy of ~2m/sis achieved. This is the highest temporal resolution for accurate mesospheric winds in the world, providing the possibility for the first vertical wind measurements in airglow to be achieved. Data analysis algorithms and procedures are developed for this instrument including a Levenberg-Marquardt technique, and a bin-by-bin analysis routine. Interesting geophysical phenomena including a large semidiurnal tide, and significant airglow intensity variations were observed during a sudden stratospheric warming. Comparisons with a meteor radar validate both instruments, and allow the determination of airglow layer heights.

  16. Technical analysis of utilization suitability of various wind rotor’s types for compressor’s power driving

    Directory of Open Access Journals (Sweden)

    Radim Rybár

    2005-03-01

    Full Text Available Conception is from the converting of wind energy, which flows across the wind turbine in mechanic work needed for compressor working. The wind motor one part of energy transform into mechanical work, part of energy is unused and part of energy of stead flow is transformed into eddy after wind rotor.The aim was rendering of technical analysis for equipment, which would use the wind with parameters for chosen area and whole unit would supply power in peak demand. Unit consists of wind turbine, which pushes compressor. Compressor pumps air into the compressed air storage. The air is used for power producing in time of peak demand.

  17. Analysis and forecasting of wind velocity in chetumal, quintana roo, using the single exponential smoothing method

    Energy Technology Data Exchange (ETDEWEB)

    Cadenas, E. [Facultad de Ingenieria Mecanica, Universidad Michoacana de San Nicolas de Hidalgo, Santiago Tapia No. 403, Centro (Mexico); Jaramillo, O.A.; Rivera, W. [Centro de Ivestigacion en Energia, Universidad Nacional Autonoma de Mexico, Apartado Postal 34, Temixco 62580, Morelos (Mexico)

    2010-05-15

    In this paper the analysis and forecasting of wind velocities in Chetumal, Quintana Roo, Mexico is presented. Measurements were made by the Instituto de Investigaciones Electricas (IIE) during two years, from 2004 to 2005. This location exemplifies the wind energy generation potential in the Caribbean coast of Mexico that could be employed in the hotel industry in the next decade. The wind speed and wind direction were measured at 10 m above ground level. Sensors with high accuracy and a low starting threshold were used. The wind velocity was recorded using a data acquisition system supplied by a 10 W photovoltaic panel. The wind speed values were measured with a frequency of 1 Hz and the average wind speed was recorded considering regular intervals of 10 min. First a statistical analysis of the time series was made in the first part of the paper through conventional and robust measures. Also the forecasting of the last day of measurements was made utilizing the single exponential smoothing method (SES). The results showed a very good accuracy of the data with this technique for an {alpha} value of 0.9. Finally the SES method was compared with the artificial neural network (ANN) method showing the former better results. (author)

  18. Analysis of Wind Turbine Simulation Models: Assessment of Simplified versus Complete Methodologies: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Honrubia-Escribano, A.; Jimenez-Buendia, F.; Molina-Garcia, A.; Fuentes-Moreno, J. A.; Muljadi, Eduard; Gomez-Lazaro, E.

    2015-09-14

    This paper presents the current status of simplified wind turbine models used for power system stability analysis. This work is based on the ongoing work being developed in IEC 61400-27. This international standard, for which a technical committee was convened in October 2009, is focused on defining generic (also known as simplified) simulation models for both wind turbines and wind power plants. The results of the paper provide an improved understanding of the usability of generic models to conduct power system simulations.

  19. Finite Element Analysis for the Web Offset of Wind Turbine Blade

    Science.gov (United States)

    Zhou, Bo; Wang, Xin; Zheng, Changwei; Cao, Jinxiang; Zou, Pingguo

    2017-05-01

    The web is an important part of wind turbine blade, which improves bending properties. Much of blade process is handmade, so web offset of wind turbine blade is one of common quality defects. In this paper, a 3D parametric finite element model of a blade for 2MW turbine was established by ANSYS. Stress distributions in different web offset values were studied. There were three kinds of web offset. The systematic study of web offset was done by orthogonal experiment. The most important factor of stress distributions was found. The analysis results have certain instructive significance to design and manufacture of wind turbine blade.

  20. Updating Finite Element Model of a Wind Turbine Blade Section Using Experimental Modal Analysis Results

    DEFF Research Database (Denmark)

    Luczak, Marcin; Manzato, Simone; Peeters, Bart

    2014-01-01

    is to validate finite element model of the modified wind turbine blade section mounted in the flexible support structure accordingly to the experimental results. Bend-twist coupling was implemented by adding angled unidirectional layers on the suction and pressure side of the blade. Dynamic test and simulations...... were performed on a section of a full scale wind turbine blade provided by Vestas Wind Systems A/S. The numerical results are compared to the experimental measurements and the discrepancies are assessed by natural frequency difference and modal assurance criterion. Based on sensitivity analysis, set...

  1. Statistical Analysis of the Impact of Wind Power on Market Quantities and Power Flows

    DEFF Research Database (Denmark)

    Pinson, Pierre; Jónsson, Tryggvi; Zugno, Marco

    2012-01-01

    In view of the increasing penetration of wind power in a number of power systems and markets worldwide, we discuss some of the impacts that wind energy may have on market quantities and cross-border power flows. These impacts are uncovered through statistical analyses of actual market and flow data...... in Europe. Due to the dimensionality and nonlinearity of these effects, the necessary concepts of dimension reduction using Principal Component Analysis (PCA), as well as nonlinear regression are described. Example application results are given for European cross-border flows, as well as for the impact...... of load and wind power forecasts on Danish and German electricity markets....

  2. Sensitivity Analysis of Wind Plant Performance to Key Turbine Design Parameters: A Systems Engineering Approach; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Dykes, K.; Ning, A.; King, R.; Graf, P.; Scott, G.; Veers, P.

    2014-02-01

    This paper introduces the development of a new software framework for research, design, and development of wind energy systems which is meant to 1) represent a full wind plant including all physical and nonphysical assets and associated costs up to the point of grid interconnection, 2) allow use of interchangeable models of varying fidelity for different aspects of the system, and 3) support system level multidisciplinary analyses and optimizations. This paper describes the design of the overall software capability and applies it to a global sensitivity analysis of wind turbine and plant performance and cost. The analysis was performed using three different model configurations involving different levels of fidelity, which illustrate how increasing fidelity can preserve important system interactions that build up to overall system performance and cost. Analyses were performed for a reference wind plant based on the National Renewable Energy Laboratory's 5-MW reference turbine at a mid-Atlantic offshore location within the United States.

  3. Market analysis onshore wind farming; Marktanalyse Windenergie an Land

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    The aim of the EEG in 2014 is that 2,500 MW net amount of onshore wind farming per year are added. Depending on how many wind turbines will be dismantled, that means the new building of 3 - 5 GW per year in the period until 2035. The newly installed capacity underline, that currently sufficient areas are available. But there are fundamentally risks in the availability of land. The planning for the provision of suitable areas is usually corresponding to upstream licensing procedures and has a very high time requirement. The volume of the area development depends on a variety of requirements and is highly dependent on the local acceptance. The question of acceptance of the planning authorities is for the government side in particular the developers and investors of a great importance. The bandwidth of today's production costs is currently 6-9 cents / kWh, with the vast majority of today operating plants and the potentials determined range from 7.5 to 9 cents / kWh. From the initial project idea up to commissioning elapse an average of 5 years. The German wind energy market is very fragmented. So is the concentration of small wind farms with less than 6 plants over 60% of all wind turbines. Furthermore the market is characterized by a wide variety of participants. From this variety of participants gives a great Competition for suitable land, but at the same time a broad and diverse area development, which has et al reflected in current new capacities. Due to the different approaches to planning in the federal states and regions planning authorities have a particular importance. Human resources and the experience of the wind power planning significantly influence the spatial control of Wind energy. For the supra-regionally project developers and manufacturers there is a great knowledge of the German Market (cost, available areas, etc.). [German] Ziel des EEG 2014 ist es, dass 2.500 MW aus Wind an Land pro Jahr netto hinzugebaut werden. Je nachdem wie viele

  4. Wind shear and turbulence on Titan: Huygens analysis

    Science.gov (United States)

    Lorenz, Ralph D.

    2017-10-01

    Wind shear measured by Doppler tracking of the Huygens probe is evaluated, and found to be within the range anticipated by pre-flight assessments (namely less than two times the Brunt-Väisälä frequency). The strongest large-scale shear encountered was ∼5 m/s/km, a level associated with 'Light' turbulence in terrestrial aviation. Near-surface winds (below 4 km) have small-scale fluctuations of ∼0.1 m/s on 1 s timescales, indicated both by probe tilt and Doppler tracking, and the characteristics of the fluctuation, of interest for future missions to Titan, can be reproduced with a simple autoregressive (AR(1)) model. The turbulent dissipation rate at an altitude of ∼500 m is found to be ∼0.2 cm2/s3, which may be a useful benchmark for atmospheric circulation models.

  5. A Study of Sound Contents Development based On Analysis and Compare Foley Sound to Actual Sound of Wind

    OpenAIRE

    Ik-Soo Ahn; Seong-Geon Bae; Myung-Jin Bae

    2015-01-01

    Foley sound of wind is often used as a background sound of radio drama in early period of broadcasting. It is one of the tools that has applied the most creative and scientific theory. This research provides scientific proof on similarities and creativity of Foley sound of wind through comparison and analysis of Foley sound and the actual wind sound.

  6. 77 FR 24941 - Vantage Wind Energy LLC; Order Accepting Updated Market Power Analysis and Providing Direction on...

    Science.gov (United States)

    2012-04-26

    ... Energy Regulatory Commission Vantage Wind Energy LLC; Order Accepting Updated Market Power Analysis and... vertical market power.\\10\\ As discussed ] below, we find that Vantage Wind satisfies the Commission's... its power to its power purchasers. Vantage Wind further states that none of Polsky Energy, Invenergy...

  7. Retrospective and prospective analysis of policy incentives for wind power in Portugal

    Science.gov (United States)

    Pena Cabra, Ivonne A.

    been decommissioned despite being in operation for more than 20 years, favoring from new, detailed and hard-to-follow agreements in the legislation. All wind parks that are currently in operation have received feed-in tariffs since they connected to the grid, and are expected to keep receiving them at least until December 2019, and up to December 2036 - depending on year of connection and agreement under the most recent legislation (Diario da Republica 2013). The 2020 renewable energy goals in Portugal include having 6.8 GW of installed wind capacity, which implies the connection of 2 GW in the next years. If no further grid investments are made and wind capacity increases up to 100 MW to the connection point that we analyze, total annual electricity spill is likely to range the 20% to 40%. If the connection grid policy is designed to allow for wind spill, already 'occupied' connection points will be available to new entrants, lowering the total investment costs for new wind parks and increasing their profitability. This thesis is divided in three main parts: a first introductory section, a retrospective study of wind power in Portugal and a prospective analysis of the Portuguese wind power sector. The introductory section is a brief overview of the global renewable status, described in Chapter 1. Chapter 2 and Chapter 3 compile a retrospective study of wind power and the policies that have incentivized wind diffusion. We include in the discussion some references to the future wind power goals, but the results and policy recommendations are directed towards the existing connected wind power capacity. (Abstract shortened by UMI.).

  8. Analysis of starting resistance moment of direct drive wind turbine

    Directory of Open Access Journals (Sweden)

    He Bin

    2016-01-01

    Full Text Available Permanent magnet motor in the process of running, the permanent magnets provided the magnetic field , the core will have a strong attraction, produce the cogging torque and torque ripple, vibration and noise and other disharmony factors, seriously affect the control precision of the motor system.Therefore, in the design of permanent magnet wind turbine generator, weaken the cogging torque is very important.

  9. A small - signal stability analysis of DFIG wind generation

    OpenAIRE

    Vittal, Eknath; O'Malley, Mark; Keane, Andrew

    2009-01-01

    This paper examines the small-signal stability impacts of high penetrations of doubly-fed induction generator (DFIG) wind turbines on power systems. It provides a basic overview of small-signal stability concepts and then examines the response of DFIG generation to two local contingency event. Using the New England 39 bus test system, this paper will demonstrate the stability implications of DFIG turbines utilizing terminal voltage control and fixed power factor control in response...

  10. Solar wind conditions leading to efficient radiation belt electron acceleration: A superposed epoch analysis

    OpenAIRE

    Li, W; Thorne, RM; Bortnik, J; Baker, DN; Reeves, GD; Kanekal, SG; Spence, HE; Green, JC

    2015-01-01

    ©2015. American Geophysical Union. All Rights Reserved. Determining preferential solar wind conditions leading to efficient radiation belt electron acceleration is crucial for predicting radiation belt electron dynamics. Using Van Allen Probes electron observations ( > 1 MeV) from 2012 to 2015, we identify a number of efficient and inefficient acceleration events separately to perform a superposed epoch analysis of the corresponding solar wind parameters and geomagnetic indices. By directly c...

  11. Calibration of GNSS-R surface wind retrievals using the ERA analysis

    Science.gov (United States)

    Danielson, Rick; Johannessen, Johnny; Cardellach, Estel; Fabra, Fran; Catarino, Nuno

    2017-04-01

    The Space GNSS Receiver Remote Sensing Instrument (SGR-ReSI) of the TechDemoSat-1 (TDS-1) satellite collected and processed about half a million fast delivery wind speed retrievals. Exploring ways to validate these data provides an opportunity, not just to quantify, but also potentially to reduce wind speed retrieval errors (in an ordinary least squares sense) and thereby improve the correspondence between the data to be calibrated and an unknown target wind analysis. The ERA Interim analysis is employed as a calibrated reference for the TDS-1 wind speed retrievals. Simultaneous assessment of error in these two collocated data leads to a global (i.e., for all collocations) and local (i.e., as a function of wind speed) determinations of statistical properties characterizing bias (both additive and multiplicative), RMS error, and correlation with an unknown target analysis. The approach taken is widely referred to as the triple collocation method (Stoffelen 1998, McColl et al. 2014), where a simplifying assumption is that three wind estimates can be obtained from these two datasets (TDS-1 and ERA).

  12. Analysis of typical world countries' wind power and PV industry policies and their enlightenment to China

    Science.gov (United States)

    Zeng, Ming; Yang, Lijun; Qiu, Hongji; Li, Yuanfei; Peng, Lilin

    2017-01-01

    The wind power and PV are the key fields of clean energy development in China in recent years. However, there are still many aspects of problems in wind power and PV industries at present, such as the insufficient consumptive ability and the limitation of market competition capability. The effective leading and support of government in the aspect of policies is especially needed in order to solve these problems. Based on the analysis of main policies system of wind power and PV in our country, Spain, the United Kingdom and Germany are chosen as typical countries because of their wind power and PV industries are relatively developed. Their policies of wind power and PV industries are studied respectively from five aspects, namely macroscopic laws, development planning, administrative policies, fiscal and tax policies and price policies. Then the comparison among typical countries and China is made and the exiting problems in China's policies of wind power and PV industries are summed up. Finally, the suggestions to promote China's wind power and PV industries development are presented.

  13. A New Global Regression Analysis Method for the Prediction of Wind Tunnel Model Weight Corrections

    Science.gov (United States)

    Ulbrich, Norbert Manfred; Bridge, Thomas M.; Amaya, Max A.

    2014-01-01

    A new global regression analysis method is discussed that predicts wind tunnel model weight corrections for strain-gage balance loads during a wind tunnel test. The method determines corrections by combining "wind-on" model attitude measurements with least squares estimates of the model weight and center of gravity coordinates that are obtained from "wind-off" data points. The method treats the least squares fit of the model weight separate from the fit of the center of gravity coordinates. Therefore, it performs two fits of "wind- off" data points and uses the least squares estimator of the model weight as an input for the fit of the center of gravity coordinates. Explicit equations for the least squares estimators of the weight and center of gravity coordinates are derived that simplify the implementation of the method in the data system software of a wind tunnel. In addition, recommendations for sets of "wind-off" data points are made that take typical model support system constraints into account. Explicit equations of the confidence intervals on the model weight and center of gravity coordinates and two different error analyses of the model weight prediction are also discussed in the appendices of the paper.

  14. A simulation-based Data Envelopment Analysis (DEA model to evaluate wind plants locations

    Directory of Open Access Journals (Sweden)

    Hossein Sameie

    2015-04-01

    Full Text Available As the world is getting overpopulated and over polluted the human being is seeking to utilize new sources of energy that are cleaner, cheaper, and more accessible. Wind is one of these clean energy sources that is accessible everywhere on the planet earth. This source of energy cannot be stored for later use; therefore, environmental circumstances and geographical location of wind plants are crucial matters. This study proposes a model to decide on the optimum location for a wind farm among the demand area. To tackle the uncertainty related to the geographical position of the nominated location such as wind speed; altitude; mean temperature; and humidity; a simulation method is applied on the problem. Other factors such as the time that a plant is out of service and demand fluctuations also have been considered in the simulation phase. Moreover, a probability distribution function is calculated for the turbine power. Then Data Envelopment Analysis (DEA performs the selection between all the nominated locations for wind farm. The proposed model takes into account several important elements of the problems. Elements such as land cost; average power received from the wind blowing; demand point population etc. are considered at the same time to select the optimum location of wind plants. Finally, the model is applied on a real case in order to demonstrate its reliability and applicability.

  15. Recent ATLAS Articles on WLAP

    CERN Multimedia

    Goldfarb, S.

    As reported in the September 2004 ATLAS eNews, the Web Lecture Archive Project is a system for the archiving and publishing of multimedia presentations, using the Web as medium. We list here newly available WLAP items relating to ATLAS: June ATLAS Plenary Meeting Tutorial on Physics EDM and Tools (June) Freiburg Overview Week Ketevi Assamagan's Tutorial on Analysis Tools Click here to browse WLAP for all ATLAS lectures.

  16. Use of meteorological information in the risk analysis of a mixed wind farm and solar

    Science.gov (United States)

    Mengelkamp, H.-T.; Bendel, D.

    2010-09-01

    Use of meteorological information in the risk analysis of a mixed wind farm and solar power plant portfolio H.-T. Mengelkamp*,** , D. Bendel** *GKSS Research Center Geesthacht GmbH **anemos Gesellschaft für Umweltmeteorologie mbH The renewable energy industry has rapidly developed during the last two decades and so have the needs for high quality comprehensive meteorological services. It is, however, only recently that international financial institutions bundle wind farms and solar power plants and offer shares in these aggregate portfolios. The monetary value of a mixed wind farm and solar power plant portfolio is determined by legal and technical aspects, the expected annual energy production of each wind farm and solar power plant and the associated uncertainty of the energy yield estimation or the investment risk. Building an aggregate portfolio will reduce the overall uncertainty through diversification in contrast to the single wind farm/solar power plant energy yield uncertainty. This is similar to equity funds based on a variety of companies or products. Meteorological aspects contribute to the diversification in various ways. There is the uncertainty in the estimation of the expected long-term mean energy production of the wind and solar power plants. Different components of uncertainty have to be considered depending on whether the power plant is already in operation or in the planning phase. The uncertainty related to a wind farm in the planning phase comprises the methodology of the wind potential estimation and the uncertainty of the site specific wind turbine power curve as well as the uncertainty of the wind farm effect calculation. The uncertainty related to a solar power plant in the pre-operational phase comprises the uncertainty of the radiation data base and that of the performance curve. The long-term mean annual energy yield of operational wind farms and solar power plants is estimated on the basis of the actual energy production and it

  17. Analysis of the Response of a 600 kW Stall Controlled Wind Turbine in Complex Terrain

    Energy Technology Data Exchange (ETDEWEB)

    Cuerva, A.; Bercebal, D.; De la Cruz, S.; Lopez-Diez, S.; Lopez-Roque, V.; Vazquez-Aguado, A.; Marti, I.; Marchante, M.; Navarro, J. [CIEMAT. Madrid (Spain)

    1998-12-31

    This work presents a detailed analysis of the operating characteristics of a 600 kW rated power wind turbine installed in complex terrain. The description of the experimental set up and analysis system is included. The relationships between parameters that describe the wind turbine response and the environmental conditions are established via high level statistical analysis, fatigue analysis and analysis is the frequency domain. Dimensionless factors are calculated to explain the intrinsic response of the structure before stochastic and deterministic wind conditions, independently from its size and wind intensity. Finally, conclusions are presented regarding the parameters that affect the loading state and power production of the machine. (Author) 12 refs.

  18. Dual-use tools and systematics-aware analysis workflows in the ATLAS Run-2 analysis model

    CERN Document Server

    FARRELL, Steven; The ATLAS collaboration; Calafiura, Paolo; Delsart, Pierre-Antoine; Elsing, Markus; Koeneke, Karsten; Krasznahorkay, Attila; Krumnack, Nils; Lancon, Eric; Lavrijsen, Wim; Laycock, Paul; Lei, Xiaowen; Strandberg, Sara Kristina; Verkerke, Wouter; Vivarelli, Iacopo; Woudstra, Martin

    2015-01-01

    The ATLAS analysis model has been overhauled for the upcoming run of data collection in 2015 at 13 TeV. One key component of this upgrade was the Event Data Model (EDM), which now allows for greater flexibility in the choice of analysis software framework and provides powerful new features that can be exploited by analysis software tools. A second key component of the upgrade is the introduction of a dual-use tool technology, which provides abstract interfaces for analysis software tools to run in either the Athena framework or a ROOT-based framework. The tool interfaces, including a new interface for handling systematic uncertainties, have been standardized for the development of improved analysis workflows and consolidation of high-level analysis tools. This paper will cover the details of the dual-use tool functionality, the systematics interface, and how these features fit into a centrally supported analysis environment.

  19. GPP user`s guide - a general-purpose postprocessor for wind turbine data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Buhl, Jr, M L

    1995-01-01

    GPP (pronounced {open_quotes}jeep{close_quotes}) is a General-Purpose Postprocessor for wind turbine data analysis. The author, a member of the Wind Technology Division (WTD) of the National Renewable Energy Laboratory (NREL), developed GPP to postprocess test data and simulation predictions. GPP reads data into large arrays and allows the user to run many types of analyses on the data stored in memory. It runs on inexpensive computers common in the wind industry. One can even use it on a laptop in the field. The author wrote the program in such a way as to make it easy to add new types of analyses and to port it to many types of computers. Although GPP is very powerful and feature-rich, it is still very easy to learn and to use. Exhaustive error trapping prevents one from losing valuable work due to input errors. GPP will, hopefully, make a significant impact on engineering productivity in the wind industry.

  20. Analysis of wind energy potential for agriculture pump in mountain area Aceh Besar

    Science.gov (United States)

    Syuhada, Ahmad; Maulana, Muhammad Ilham; Fuadi, Zahrul

    2017-06-01

    In this study, the potential of wind power for agricultural pump driver in Saree mountainous area of Aceh Besar is analyzed. It is found that the average usable wind speed is 6.41 m/s, which is potential to produce 893.96 Watt of electricity with the wind turbine rotor diameter of 3 m. This energy can be used to drive up to 614 Watt of water pump with static head of 20 m to irrigate 19 hectare of land, 7 hours a day. HOMER analysis indicated the lowest simulated NPC value of USD 10.028 with CoE of USD 0.717 kWh. It is also indicated that the wind has potential to produce 3452 kWh/year with lifetime of 15 years.

  1. Operational modal analysis on a VAWT in a large wind tunnel using stereo vision technique

    DEFF Research Database (Denmark)

    Najafi, Nadia; Schmidt Paulsen, Uwe

    2017-01-01

    This paper is about development and use of a research based stereo vision system for vibration and operational modal analysis on a parked, 1-kW, 3-bladed vertical axis wind turbine (VAWT), tested in a wind tunnel at high wind. Vibrations were explored experimentally by tracking small deflections...... of the markers on the structure with two cameras, and also numerically, to study structural vibrations in an overall objective to investigate challenges and to prove the capability of using stereo vision. Two high speed cameras provided displacement measurements at no wind speed interference. The displacement...... 2 x 105. VAWT dynamics were simulated using HAWC2. The stereo vision results and HAWC2 simulations agree within 4% except for mode 3 and 4. The high aerodynamic damping of one of the blades, in flatwise motion, would explain the gap between those two modes from simulation and stereo vision. A set...

  2. Analysis of Oscillations in a Cableway: Wind Load Effects

    Directory of Open Access Journals (Sweden)

    Jan Gustincic

    2013-06-01

    Full Text Available The purpose of this paper is to develop and investigate a non-linear model for analysing the reaction of a self-detachable cabin monocable ropeway exposed to a sudden deceleration and wind forces. The First and Second Newton's Law and Differential Equations are the basic tools for building the model. Furthermore a few basic considerations have been made about the air “dragging and lifting" forces that induce oscillations and vibrations in mechanical systems alike. All the numerical data used for the simulation was taken from a ropeway in the skiing site of Ravascletto-Zoncolan in the North- East of Italy.

  3. Multi-Instrument Data Analysis of Thermospheric Density and Winds

    Science.gov (United States)

    Pilinski, Marcin

    The Drag and Atmospheric Neutral Density Explorer (DANDE) is a 50 kg, 0.45 meter diameter, spherical spacecraft being developed at the University of Colorado, Boulder. The goal of the DANDE mission is to make in-situ measurements of density, composition, and winds at altitudes between 200 and 350 km. The relationship between these quantities during both disturbed and quiet atmospheric conditions as well as the relative effect of these parameters on satellite drag will be addressed using simultaneous measurements from two instruments. The first is the Wind and Atmospheric Temperature Spectrometer (WATS) and is a miniaturized electrostatic energy analyzer. The second is an experimental acceleration measuring system which takes advantage of the spacecraft spin to modulate the drag acceleration to a known frequency and uses a suite of commercially available accelerometers as detectors. To evaluate this novel method of atmospheric data collection, a comprehensive model of its components is under development. In addition to being a scientific and operational assessment of the spacecraft data products, this work also represents the engineering error model which helps drive the selection and design of system components. The simulation is composed of environmental, spacecraft, and instrument models and, given inputs such as solar F10.7, results in simulated on-orbit data. These data products are compared to model values so that errors can be determined and cataloged statistically. The errors are then compared to those assumed in assimilative thermosphere modeling studies to evaluate how well a spacecraft like DANDE could be used to improve nowcasting and density determination. The spacecraft model is composed of attitude and orbital dynamics, thermal cycling inputs, and variations in the coefficient of drag. WATS instrument simulation is based upon the statistical error descriptions of an ion-optics study conducted at the Goddard Space Flight Center. Modeling of the

  4. Failure Analysis of Large-Scale Wind Power Structure under Simulated Typhoon

    Directory of Open Access Journals (Sweden)

    Zihua Zhang

    2014-01-01

    Full Text Available Recently, a number of wind power structures in tropical cyclone zones are damaged by typhoon. In order to study the failure mechanics and failure modes of wind power structure subjected to typhoon, the typhoon wind field in Dongtai wind farm is simulated based on the classical autoregressive (AR model and a regional power-spectrum-density (PSD model, and the simulated spectrum is verified to be in good agreement with the target spectrum. An integrated finite element (FE model of wind power structure, composed of rotor, nacelle, tower, pile cap, and PHC piles, is established. Modal analysis reveals that pile stiffness decreases the structure’s natural frequencies, especially for high order frequencies. Structural responses under the simulated typhoon are calculated by dynamic analysis. Results show that tower buckling is the most prone failure mode of the structure. The horizontal displacement of the hub and the axial force of the most unfavorable piles are both under the limit. This study provides a way to the antityphoon design of large-scale wind power structures.

  5. A verification study and trend analysis of simulated boundary layer wind fields over Europe

    Energy Technology Data Exchange (ETDEWEB)

    Lindenberg, Janna

    2011-07-01

    Simulated wind fields from regional climate models (RCMs) are increasingly used as a surrogate for observations which are costly and prone to homogeneity deficiencies. Compounding the problem, a lack of reliable observations makes the validation of the simulated wind fields a non trivial exercise. Whilst the literature shows that RCMs tend to underestimate strong winds over land these investigations mainly relied on comparisons with near surface measurements and extrapolated model wind fields. In this study a new approach is proposed using measurements from high towers and a robust validation process. Tower height wind data are smoother and thus more representative of regional winds. As benefit this approach circumvents the need to extrapolate simulated wind fields. The performance of two models using different downscaling techniques is evaluated. The influence of the boundary conditions on the simulation of wind statistics is investigated. Both models demonstrate a reasonable performance over flat homogeneous terrain and deficiencies over complex terrain, such as the Upper Rhine Valley, due to a too coarse spatial resolution ({proportional_to}50 km). When the spatial resolution is increased to 10 and 20 km respectively a benefit is found for the simulation of the wind direction only. A sensitivity analysis shows major deviations of international land cover data. A time series analysis of dynamically downscaled simulations is conducted. While the annual cycle and the interannual variability are well simulated, the models are less effective at simulating small scale fluctuations and the diurnal cycle. The hypothesis that strong winds are underestimated by RCMs is supported by means of a storm analysis. Only two-thirds of the observed storms are simulated by the model using a spectral nudging approach. In addition ''False Alarms'' are simulated, which are not detected in the observations. A trend analysis over the period 1961 - 2000 is conducted

  6. U.S. Wind Energy Manufacturing and Supply Chain: A Competitiveness Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Fullenkamp, Patrick H; Holody, Diane S

    2014-06-15

    The goal of the project was to develop a greater understanding of the key factors determining wind energy component manufacturing costs and pricing on a global basis in order to enhance the competitiveness of U.S. manufacturers, and to reduce installed systems cost. Multiple stakeholders including DOE, turbine OEMs, and large component manufactures will all benefit by better understanding the factors determining domestic competitiveness in the emerging offshore and next generation land-based wind industries. Major objectives of this project were to: 1. Carry out global cost and process comparisons for 5MW jacket foundations, blades, towers, and permanent magnet generators; 2. Assess U.S. manufacturers’ competitiveness and potential for cost reduction; 3. Facilitate informed decision-making on investments in U.S. manufacturing; 4. Develop an industry scorecard representing the readiness of the U.S. manufacturers’ to produce components for the next generations of wind turbines, nominally 3MW land-based and 5MW offshore; 5. Disseminate results through the GLWN Wind Supply Chain GIS Map, a free website that is the most comprehensive public database of U.S. wind energy suppliers; 6. Identify areas and develop recommendations to DOE on potential R&D areas to target for increasing domestic manufacturing competitiveness, per DOE’s Clean Energy Manufacturing Initiative (CEMI). Lists of Deliverables 1. Cost Breakdown Competitive Analyses of four product categories: tower, jacket foundation, blade, and permanent magnet (PM) generator. The cost breakdown for each component includes a complete Bill of Materials with net weights; general process steps for labor; and burden adjusted by each manufacturer for their process categories of SGA (sales general and administrative), engineering, logistics cost to a common U.S. port, and profit. 2. Value Stream Map Competitiveness Analysis: A tool that illustrates both information and material flow from the point of getting a

  7. Analysis of winter weather conditions and their potential impact on wind farm operations

    Science.gov (United States)

    Novakovskaia, E.; Treinish, L. A.; Praino, A.

    2009-12-01

    Severe weather conditions have two primary impacts on wind farm operations. The first relates to understanding potential damage to the turbines themselves and what actions are required to mitigate the effects. The second is recognizing what conditions may lead to a full or partial shutdown of the wind farm with sufficient lead time to determine the likely inability to meet energy generation committments. Ideally, wind forecasting suitable for wind farm operations should be of sufficient fidelity to resolve features within the boundary layer that lead to either damaging conditions or useful power generation. Given the complexity of the site-specific factors that effect the boundary layer at the scale of typical land-based wind farm locations such as topography, vegetation, land use, soil conditions, etc., which may vary with turbine design and layout within the farm, enabling reliable forecasts of too little or too much wind is challenging. A potential solution should involve continuous updates of alert triggering criteria through analysis of local wind patterns and probabilistic risk assessment for each location. To evaluate this idea, we utilize our operational mesoscale prediction system, dubbed “Deep Thunder”, developed at the IBM Thomas J. Watson Research Center. In particular, we analyze winter-time near-surface winds in upstate New York, where four similar winds farms are located. Each of these farms were built at roughly the same time and utilize similar turbines. Given the relative uncertainty associated with numerical weather prediction at this scale, and the difference in risk assessment due to the two primary impacts of severe weather, probabilistic forecasts are a prerequisite. Hence, we have employed ensembles of weather scenarios, which are based on the NCAR WRF-ARW modelling system. The set of ensemble members was composed with variations in the choices of physics and parameterization schemes, and source of background fields for initial

  8. Computational analysis of vertical axis wind turbine arrays

    Science.gov (United States)

    Bremseth, J.; Duraisamy, K.

    2016-10-01

    Canonical problems involving single, pairs, and arrays of vertical axis wind turbines (VAWTs) are investigated numerically with the objective of understanding the underlying flow structures and their implications on energy production. Experimental studies by Dabiri (J Renew Sustain Energy 3, 2011) suggest that VAWTs demand less stringent spacing requirements than their horizontal axis counterparts and additional benefits may be obtained by optimizing the placement and rotational direction of VAWTs. The flowfield of pairs of co-/counter-rotating VAWTs shows some similarities with pairs of cylinders in terms of wake structure and vortex shedding. When multiple VAWTs are placed in a column, the extent of the wake is seen to spread further downstream, irrespective of the direction of rotation of individual turbines. However, the aerodynamic interference between turbines gives rise to regions of excess momentum between the turbines which lead to significant power augmentations. Studies of VAWTs arranged in multiple columns show that the downstream columns can actually be more efficient than the leading column, a proposition that could lead to radical improvements in wind farm productivity.

  9. Analysis Preservation and Systematic Reinterpretation within the ATLAS Experiment

    CERN Document Server

    Heinrich, Lukas; The ATLAS collaboration

    2017-01-01

    The LHC data analysis software used in order to derive and publish experimental results is an important asset that is necessary to preserve in order to fully exploit the scientific potential of a given measurement. Among others, important use cases of analysis preservation are the reproducibility of the original results and the reusability of the analysis procedure in the context of new scientific studies. A prominent use-case for the latter is the systematic reinterpretation of searches for new Physics in terms of signal models that not studied in the original publication (RECAST). This paper presents the usage of the graph-based workflow description language yadage to drive the reinterpretation of preserved HEP analyses. The analysis software for individual states in the analysis is preserved using Docker containers, while the workflow structure is preserved using plain JSON documents. This allows the re-execution of complex analysis workflows on industry standard container-based distributed computing clust...

  10. Operational modal analysis and wavelet transformation for damage identification in wind turbine blades

    DEFF Research Database (Denmark)

    Ulriksen, Martin Dalgaard; Tcherniak, Dmitri; Kirkegaard, Poul Henning

    2014-01-01

    The presented study demonstrates an application of a previously proposed modal and wavelet analysis-based damage identification method to a wind turbine blade. A trailing edge debonding was introduced to a SSP 34m blade mounted on a test rig. Operational modal analysis (OMA) was conducted to obtain...

  11. Operational Modal Analysis and Wavelet Transformation for Damage Identification in Wind Turbine Blades

    DEFF Research Database (Denmark)

    Ulriksen, Martin Dalgaard; Tcherniak, Dmitri; Kirkegaard, Poul Henning

    2016-01-01

    This study demonstrates an application of a previously proposed modal and wavelet analysis-based damage identification method to a wind turbine blade. A trailing edge debonding was introduced to an SSP 34-m blade mounted on a test rig. Operational modal analysis was conducted to obtain mode shapes...

  12. Trigger-object Level Analysis with the ATLAS detector at the Large Hadron Collider: summary and perspectives

    CERN Document Server

    The ATLAS collaboration

    2017-01-01

    This document summarizes the motivations, challenges and perspectives on the Trigger-object Level Analysis (TLA) in ATLAS, focusing on the case where the objects are hadronic jets. It is intended as a complement to the HEP Software Foundation Community Whitepaper on trigger and reconstruction.

  13. Phasor model of full scale converter wind turbine for small-signal stability analysis

    DEFF Research Database (Denmark)

    Gihga, Radu; Wu, Qiuwei; Nielsen, Arne Hejde

    2017-01-01

    The small-signal stability analysis of power system electromechanical oscillations is a well-established field in control and stability assessment of power systems. The impact of large wind farms on small-signal stability of power systems has been a topic of high interest in recent years....... This study presents a phasor model of full scale converter wind turbines (WTs) implemented in MATLAB/SIMULINK for small-signal stability studies. The phasor method is typically used for dynamic studies of power systems consisting of large electric machines. It can also be applied to any linear system....... This represents an advantage in small-signal stability studies, which are based on modal analysis of the linearised model and are usually complemented with dynamic simulations. The proposed model can represent a single WT or an aggregated wind power plant. The implemented model for small-signal stability analysis...

  14. Analysis Preservation and Systematic Reinterpretation within the ATLAS experiment

    CERN Document Server

    Heinrich, Lukas; The ATLAS collaboration

    2017-01-01

    The LHC data analysis software used in order to derive and publish experimental results is an important asset that is necessary to preserve in order to fully exploit the scientific potential of a given measurement. An important use-case is the re-usability of the analysis procedure in the context of new scientific studies such as the reinterpretation of searches for new Physics in terms of signal models that not studied in the original publication (RECAST). We present the usage of the graph-based workflow description language yadage to drive the reinterpretation of preserved HEP analyses. The analysis software is preserved using Docker containers, while the workflow structure is preserved using plain JSON documents. This allows the re-execution of complex analysis workflows on modern distributed container orchestration systems and enables a systematic reinterpretation service based on such preserved analysis.

  15. The Wind ENergy Data and Information (WENDI) Gateway: New Information and Analysis Tools for Wind Energy Stakeholders

    Science.gov (United States)

    Kaiser, D.; Palanisamy, G.; Santhana Vannan, S.; Wei, Y.; Smith, T.; Starke, M.; Wibking, M.; Pan, Y.; Devarakonda, Ranjeet; Wilson, B. E.; Wind Energy Data; Information (WENDI) Gateway Team

    2010-12-01

    In support of the U.S. Department of Energy’s (DOE) Energy Efficiency and Renewable Energy (EERE) Office, DOE's Oak Ridge National Laboratory (ORNL) has launched the Wind ENergy Data & Information (WENDI) Gateway. The WENDI Gateway is intended to serve a broad range of wind-energy stakeholders by providing easy access to a large amount of wind energy-related data and information through its two main interfaces: the Wind Energy Metadata Clearinghouse and the Wind Energy Geographic Information System (WindGIS). The Metadata Clearinghouse is a powerful, customized search tool for discovering, accessing, and sharing wind energy-related data and information. Its database of metadata records points users to a diverse array of wind energy-related resources: from technical and scientific journal articles to mass media news stories; from annual government and industry reports to downloadable datasets, and much more. Through the WindGIS, users can simultaneously visualize a wide spectrum of United States wind energy-related spatial data, including wind energy power plant locations; wind resource maps; state-level installed wind capacity, generation, and renewable portfolio standards; electric transmission lines; transportation infrastructure; interconnection standards; land ownership, designation, and usage; and various ecological data layers. In addition, WindGIS allows users to download much of the data behind the layers. References: [1] Devarakonda R., et al. Mercury: reusable metadata management, data discovery and access system. Earth Science Informatics (2010), 3(1): 87-94. [2] Wilson, Bruce E., et al. "Mercury Toolset for Spatiotemporal Metadata." (2010).

  16. Using a Hybrid Cost-FMEA Analysis for Wind Turbine Reliability Analysis

    Directory of Open Access Journals (Sweden)

    Nacef Tazi

    2017-02-01

    Full Text Available Failure mode and effects analysis (FMEA has been proven to be an effective methodology to improve system design reliability. However, the standard approach reveals some weaknesses when applied to wind turbine systems. The conventional criticality assessment method has been criticized as having many limitations such as the weighting of severity and detection factors. In this paper, we aim to overcome these drawbacks and develop a hybrid cost-FMEA by integrating cost factors to assess the criticality, these costs vary from replacement costs to expected failure costs. Then, a quantitative comparative study is carried out to point out average failure rate, main cause of failure, expected failure costs and failure detection techniques. A special reliability analysis of gearbox and rotor-blades are presented.

  17. The AAL project: automated monitoring and intelligent analysis for the ATLAS data taking infrastructure

    Science.gov (United States)

    Kazarov, A.; Lehmann Miotto, G.; Magnoni, L.

    2012-06-01

    The Trigger and Data Acquisition (TDAQ) system of the ATLAS experiment at CERN is the infrastructure responsible for collecting and transferring ATLAS experimental data from detectors to the mass storage system. It relies on a large, distributed computing environment, including thousands of computing nodes with thousands of application running concurrently. In such a complex environment, information analysis is fundamental for controlling applications behavior, error reporting and operational monitoring. During data taking runs, streams of messages sent by applications via the message reporting system together with data published from applications via information services are the main sources of knowledge about correctness of running operations. The flow of data produced (with an average rate of O(1-10KHz)) is constantly monitored by experts to detect problem or misbehavior. This requires strong competence and experience in understanding and discovering problems and root causes, and often the meaningful information is not in the single message or update, but in the aggregated behavior in a certain time-line. The AAL project is meant at reducing the man power needs and at assuring a constant high quality of problem detection by automating most of the monitoring tasks and providing real-time correlation of data-taking and system metrics. This project combines technologies coming from different disciplines, in particular it leverages on an Event Driven Architecture to unify the flow of data from the ATLAS infrastructure, on a Complex Event Processing (CEP) engine for correlation of events and on a message oriented architecture for components integration. The project is composed of 2 main components: a core processing engine, responsible for correlation of events through expert-defined queries and a web based front-end to present real-time information and interact with the system. All components works in a loose-coupled event based architecture, with a message broker

  18. A wind proxy based on migrating dunes at the Baltic coast: statistical analysis of the link between wind conditions and sand movement

    Science.gov (United States)

    Bierstedt, Svenja E.; Hünicke, Birgit; Zorita, Eduardo; Ludwig, Juliane

    2017-07-01

    We statistically analyse the relationship between the structure of migrating dunes in the southern Baltic and the driving wind conditions over the past 26 years, with the long-term aim of using migrating dunes as a proxy for past wind conditions at an interannual resolution. The present analysis is based on the dune record derived from geo-radar measurements by Ludwig et al. (2017). The dune system is located at the Baltic Sea coast of Poland and is migrating from west to east along the coast. The dunes present layers with different thicknesses that can be assigned to absolute dates at interannual timescales and put in relation to seasonal wind conditions. To statistically analyse this record and calibrate it as a wind proxy, we used a gridded regional meteorological reanalysis data set (coastDat2) covering recent decades. The identified link between the dune annual layers and wind conditions was additionally supported by the co-variability between dune layers and observed sea level variations in the southern Baltic Sea. We include precipitation and temperature into our analysis, in addition to wind, to learn more about the dependency between these three atmospheric factors and their common influence on the dune system. We set up a statistical linear model based on the correlation between the frequency of days with specific wind conditions in a given season and dune migration velocities derived for that season. To some extent, the dune records can be seen as analogous to tree-ring width records, and hence we use a proxy validation method usually applied in dendrochronology, cross-validation with the leave-one-out method, when the observational record is short. The revealed correlations between the wind record from the reanalysis and the wind record derived from the dune structure is in the range between 0.28 and 0.63, yielding similar statistical validation skill as dendroclimatological records.

  19. Permutation entropy and statistical complexity analysis of turbulence in laboratory plasmas and the solar wind

    Science.gov (United States)

    Weck, P. J.; Schaffner, D. A.; Brown, M. R.; Wicks, R. T.

    2015-02-01

    The Bandt-Pompe permutation entropy and the Jensen-Shannon statistical complexity are used to analyze fluctuating time series of three different turbulent plasmas: the magnetohydrodynamic (MHD) turbulence in the plasma wind tunnel of the Swarthmore Spheromak Experiment (SSX), drift-wave turbulence of ion saturation current fluctuations in the edge of the Large Plasma Device (LAPD), and fully developed turbulent magnetic fluctuations of the solar wind taken from the Wind spacecraft. The entropy and complexity values are presented as coordinates on the CH plane for comparison among the different plasma environments and other fluctuation models. The solar wind is found to have the highest permutation entropy and lowest statistical complexity of the three data sets analyzed. Both laboratory data sets have larger values of statistical complexity, suggesting that these systems have fewer degrees of freedom in their fluctuations, with SSX magnetic fluctuations having slightly less complexity than the LAPD edge Isat. The CH plane coordinates are compared to the shape and distribution of a spectral decomposition of the wave forms. These results suggest that fully developed turbulence (solar wind) occupies the lower-right region of the CH plane, and that other plasma systems considered to be turbulent have less permutation entropy and more statistical complexity. This paper presents use of this statistical analysis tool on solar wind plasma, as well as on an MHD turbulent experimental plasma.

  20. Visualization and analysis of vortex-turbine intersections in wind farms.

    Science.gov (United States)

    Shafii, Sohail; Obermaier, Herald; Linn, Rodman; Koo, Eunmo; Hlawitschka, Mario; Garth, Christoph; Hamann, Bernd; Joy, Kenneth I

    2013-09-01

    Characterizing the interplay between the vortices and forces acting on a wind turbine's blades in a qualitative and quantitative way holds the potential for significantly improving large wind turbine design. This paper introduces an integrated pipeline for highly effective wind and force field analysis and visualization. We extract vortices induced by a turbine's rotation in a wind field, and characterize vortices in conjunction with numerically simulated forces on the blade surfaces as these vortices strike another turbine's blades downstream. The scientifically relevant issue to be studied is the relationship between the extracted, approximate locations on the blades where vortices strike the blades and the forces that exist in those locations. This integrated approach is used to detect and analyze turbulent flow that causes local impact on the wind turbine blade structure. The results that we present are based on analyzing the wind and force field data sets generated by numerical simulations, and allow domain scientists to relate vortex-blade interactions with power output loss in turbines and turbine life expectancy. Our methods have the potential to improve turbine design to save costs related to turbine operation and maintenance.

  1. Time Domain Response Analysis of Barge Floater Supporting an Offshore Wind Turbine

    Directory of Open Access Journals (Sweden)

    A.C. Mayilvahanan

    2011-12-01

    Full Text Available Wind energy is a reliable source of sustainable power generation and has been an active area of research globally to economically harness the energy for human use. Reliable source of wind energy pushed the engineers to install wind turbines near and far off the coasts. In shallow water upto 100 m, fixed structures like tripods, jackets, monopiles and gravity base are functionally and economically feasible. In deep waters, a floating substructure can be more economical for offshore wind turbine. In this study a barge type floater of different aspect ratios from 0.4 to 1.0 is investigated for its performance under wave and wind loading. All these floaters were designed with a defined transverse metacentric height (GM equal to 1.0 m and the hydrodynamic analysis is carried out using WAMIT. The barge with aspect ratio B/L = 1.0 is found to have lowest pitch RAO. The time domain surge, heave and pitch response for this barge has been obtained using Integro-differential equation of motion and the statistical response characteristics are compared for two different cases of excitation namely, wave excitation alone and combined wave and wind excitation. Statistics of surge, heave and pitch responses are obtained for three different seas states and for two different wave heading angles.

  2. Spectral analysis of meteorites ablated in a wind tunnel

    Science.gov (United States)

    Drouard, A.; Vernazza, P.; Loehle, S.; Gattacceca, J.; Zander, T.; Eberhart, M.; Meindl, A.; Oefele, R.; Vaubaillon, J.; Colas, F.

    2017-09-01

    Recently and for the very first time, experiments simulating vaporization of a meteorite sample were performed in a wind tunnel near Stuttgart with the specific aim to record emission spectra of the vaporized material. Using a high enthalpy air plasma flow for modeling an equivalent air friction of an entry speed of about 10 km/s, three meteorite types (H, CM and HED) and two meteoritical analogues (basalt and argillite) were ablated and high resolution spectra were recorded simultaneously. After the identification of all atomic lines, we per- formed a detailed study of our spectra using two approaches: (i) by direct comparison of multiplet in- tensities between the samples and (ii) by computation of a synthetic spectrum to constrain some physical parameters (temperature, elemental abundance). Finally, we compared our results to the elemental composition of our samples and we determined how much compositional information can be retrieved for a given meteor using visible sectroscopy.

  3. Analysis of Craniofacial Images using Computational Atlases and Deformation Fields

    OpenAIRE

    Ólafsdóttir, Hildur; Ersbøll, Bjarne Kjær; Larsen, Rasmus

    2008-01-01

    The topic of this thesis is automatic analysis of craniofacial images. The methods proposed and applied contribute to the scientific knowledge about different craniofacial anomalies, in addition to providing tools for detailed and robust analysis of craniofacial images for clinical and research purposes. The basis for most of the applications is non-rigid image registration. This approach brings one image into the coordinate system of another resulting in a deformation field describing the an...

  4. Reliability analysis of a gravity-based foundation for wind turbines

    DEFF Research Database (Denmark)

    Vahdatirad, Mohammad Javad; Griffiths, D. V.; Andersen, Lars Vabbersgaard

    2014-01-01

    Deterministic code-based designs proposed for wind turbine foundations, are typically biased on the conservative side, and overestimate the probability of failure which can lead to higher than necessary construction cost. In this study reliability analysis of a gravity-based foundation concerning...... technique to perform the reliability analysis. The calibrated code-based design approach leads to savings of up to 20% in the concrete foundation volume, depending on the target annual reliability level. The study can form the basis for future optimization on deterministic-based designs for wind turbine...... foundations....

  5. Enabling data analysis à la PROOF on the Italian ATLAS Tier2 using PoD

    CERN Document Server

    Di Nardo, R; The ATLAS collaboration; Vilucchi, E; Annovi, A; Antonelli, M; Carlino, G; De Salvo, A; Doria, A; Manafov, A; Martini, A; Testa, A

    2012-01-01

    We describe our experience using PROOF for data analysis on the Italian ATLAS-Tier2 in Frascati, Napoli and Roma1. To enable PROOF on the cluster we used PoD, Proof- on-Demand. PoD is a set of tools designed to interact with any resource management system (RMS) to start the PROOF daemons. In this way any user can quickly setup its own PROOF cluster on the resources, with the RMS taking care of scheduling, priorities and accounting. Usage of PoD has steadily increased in the last years, and the product has now reached a production level quality. PoD features an abstract interface to RMSs and provides several plugins for the most common RMSs. In our tests we used both the gLite and PBS plug-ins, the latter being the native RMS handling the resources under test. Data were accessed via xrootd, with file discovery provided by the standard ATLAS tools. The SRM is DPM (Disk Pool Manager) which has rfio as standard data access protocol; so we provided DPM of Xrootd protocol too. We will describe the configuration and...

  6. Diagnostic analysis of silicon strips detector readout in the ATLAS Semi-Conductor Tracker module production

    CERN Document Server

    Ciocio, Alessandra

    2005-01-01

    The ATLAS Semi-Conductor Tracker (SCT) Collaboration is currently in the production phase of fabricating and testing silicon strips modules for the ATLAS detector at the Large Hadron Collider being built at the CERN laboratory in Geneva, Switzerland. A small but relevant percentage of ICs developed a new set of defects after being mounted on hybrids that were not detected in the wafer screening. To minimize IC replacement and outright module failure, analysis methods were developed to study IC problems during the production of SCT modules. These analyses included studying wafer and hybrid data correlations to finely tune the selection of ICs and tests to utilize the ability to adjust front-end parameters of the IC in order to reduce the rejection and replacement rate of fabricated components. This paper will discuss a few examples of the problems encountered during the production of SCT hybrids and modules in the area of ICs performance, and will demonstrate the value of the flexibility built into the ABCD3T ...

  7. Distributed analysis functional testing using GangaRobot in the ATLAS experiment

    CERN Document Server

    Legger, F; The ATLAS collaboration

    2011-01-01

    Automated distributed analysis tests are necessary to ensure smooth operations of the ATLAS grid resources. The HammerCloud framework allows for easy definition, submission and monitoring of grid test applications. Both functional and stress test applications can be defined in HammerCloud. Stress tests are large-scale tests meant to verify the behaviour of sites under heavy load. Functional tests are light user applications running at each site with high frequency, to ensure that the site functionalities are available at all times. Success or failure rates of these tests jobs are individually monitored. Test definitions and results are stored in a database and made available to users and site administrators through a web interface. In this work we present the recent developments of the GangaRobot framework. GangaRobot monitors the outcome of functional tests, creates a blacklist of sites failing the tests, and exports the results tothe ATLAS Site Status Board (SSB) and to the Service Availability Monitor (SAM...

  8. Oscillatory Stability and Eigenvalue Sensitivity Analysis of A DFIG Wind Turbine System

    DEFF Research Database (Denmark)

    Yang, Lihui; Xu, Zhao; Østergaard, Jacob

    2011-01-01

    This paper focuses on modeling and oscillatory stability analysis of a wind turbine with doubly fed induction generator (DFIG). A detailed mathematical model of DFIG wind turbine with vector-control loops is developed, based on which the loci of the system Jacobian's eigenvalues have been analyzed......, showing that, without appropriate controller tuning a Hopf bifurcation can occur in such a system due to various factors, such as wind speed. Subsequently, eigenvalue sensitivity with respect to machine and control parameters is performed to assess their impacts on system stability. Moreover, the Hopf...... bifurcation boundaries of the key parameters are also given. They can be used to guide the tuning of those DFIG parameters to ensure stable operation in practice. The computer simulations are conducted to validate the developed model and to verify the theoretical analysis....

  9. Damage Analysis and Evaluation of Light Steel Structures Exposed to Wind Hazards

    Directory of Open Access Journals (Sweden)

    Na Yang

    2017-03-01

    Full Text Available Compared to hot-rolled steel structures, cold-formed steel structures are susceptible to extreme winds because of the light weight of the building and its components. Many modern cold-formed steel structures have sustained significant structural damage ranging from loss of cladding to complete collapse in recent cyclones. This article first provides some real damage cases for light steel structures induced by the high winds. After that, the paper reviews research on the damage analysis and evaluation of light steel structures caused by strong winds, which include connection failure, fatigue failure, purlin buckling, and primary frame component instability problems. Moreover, this review will mention some applications of structure damage assessment methods in this area, such as vulnerability analysis and performance-based theory, etc.

  10. An analysis of methods for the selection of atlases for use in medical image segmentation

    Science.gov (United States)

    Prescott, Jeffrey W.; Best, Thomas M.; Haq, Furqan; Jackson, Rebecca; Gurcan, Metin

    2010-03-01

    The use of atlases has been shown to be a robust method for segmentation of medical images. In this paper we explore different methods of selection of atlases for the segmentation of the quadriceps muscles in magnetic resonance (MR) images, although the results are pertinent for a wide range of applications. The experiments were performed using 103 images from the Osteoarthritis Initiative (OAI). The images were randomly split into a training set consisting of 50 images and a testing set of 53 images. Three different atlas selection methods were systematically compared. First, a set of readers was assigned the task of selecting atlases from a training population of images, which were selected to be representative subgroups of the total population. Second, the same readers were instructed to select atlases from a subset of the training data which was stratified based on population modes. Finally, every image in the training set was employed as an atlas, with no input from the readers, and the atlas which had the best initial registration, judged by an appropriate registration metric, was used in the final segmentation procedure. The segmentation results were quantified using the Zijdenbos similarity index (ZSI). The results show that over all readers the agreement of the segmentation algorithm decreased from 0.76 to 0.74 when using population modes to assist in atlas selection. The use of every image in the training set as an atlas outperformed both manual atlas selection methods, achieving a ZSI of 0.82.

  11. An Analysis of the Radiation Damage to the ATLAS Semiconductor Tracker End-Caps

    CERN Document Server

    Millar, Declan; Moretti, Stefano

    The motivation, theoretical principles and analytical procedure for an assessment of the radiation damage to the ATLAS SCT end-caps is presented. An analysis of the leakage current across end-cap modules is performed for 2011 and 2012 data. A comparison between the observed and expected leakage current is made, with measurements favouring the shape of the theoretical evolution. Measured data is found to be systematically lower than predicted for a large subset of end-cap modules, while the remainder show surface current effects which interfere with bulk current observation. Uniform differences for modules at different radial distances suggest a radial temperature distribution in the end-caps, with absolute silicon sensor temperature to be established in further analysis.

  12. Design and Analysis of Wind Turbine Blade Hub using Aluminium Alloy AA 6061-T6

    Science.gov (United States)

    Ravikumar, S.; Jaswanthvenkatram, V.; Sai kumar, Y. J. N. V.; Sohaib, S. Md.

    2017-05-01

    This work presents the design and analysis of horizontal axis wind turbine blade hub using different material. The hub is very crucial part of the wind turbine, which experience the loads from the blades and the loads were transmitted to the main shaft. At present wind turbine is more expensive and weights more than a million pounds, with the nacelle, rotor hub and blades accounting for most of the weight. In this work Spheroidal graphite cast iron GGG 40.3 is replaced by aluminium alloy 6061-T6 to enhance the casting properties and also to improve the strength-weight ratio. This transition of material leads to reduction in weight of the wind turbine. All the loads caused by wind and extreme loads on the blades are transferred to the hub. Considering the IEC 61400-1 standard for defining extreme loads on the hub the stress and deflection were calculated on the hub by using Finite element Analysis. Result obtained from ANSYS is compared and discussed with the existing design.

  13. Multipoint analysis of compressive fluctuations in the fast and slow solar wind

    Science.gov (United States)

    Roberts, O. W.; Narita, Y.; Li, X.; Escoubet, C. P.; Laakso, H.

    2017-07-01

    Compressible turbulence in the solar wind is a topic of much recent debate. To understand the various compressive fluctuations at scales comparable to proton characteristic lengths, we use multipoint magnetic field and density data (derived from spacecraft potential which allows higher time resolution than is typically possible than with particle instruments) from the Cluster spacecraft when they were in undisturbed intervals of slow and fast solar wind. The application of the multipoint signal resonator technique is performed for the first time, to the analysis of scalar time series. Fluctuations in the measurements of electron density and in magnitude of the magnetic field (used as a proxy for compressible magnetic fluctuations) are used as inputs in addition to the traditional vector components of the magnetic field. This analysis is performed on two streams of solar wind, one which can be classed as a slow stream and one which can be classed as a fast stream to investigate the difference in the compressible components in the two types of wind. The recovered plasma frame frequencies for the incompressible component show low propagation speed in the plasma frame consistent with previous applications of the method, while the compressible components are more scattered, some with very high phase speeds. Based on these results, we propose a picture of compressive solar wind turbulence as a mixed state of (1) linear modes such as kinetic Alfvén, kinetic slow, and ion Bernstein modes; (2) coherent structures with very small intrinsic frequencies; and (3) nonlinear or sideband modes.

  14. Wavelet spectral analysis of the temperature and wind speed data at Adrar, Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Chellali, F. [Unite de Recherche Appliquee en Energies Renouvelables, Ghardaia (Algeria); Ecole Nationale Polytechnique, ENP, El-Harrach (Algeria); Khellaf, A. [Centre de Recherche et Developpement des Energies Renouvelables, CDER, Bouzeriah (Algeria); Belouchrani, A. [Ecole Nationale Polytechnique, ENP, El-Harrach (Algeria)

    2010-06-15

    Spectra of many meteorological data such as wind speed and temperature are time variable. Thus a Fourier analysis is not sufficient. In the present work, the wavelet transform is applied as a time-frequency analysis to the meteorological data for the region of Adrar (27.9 N, 0.3 W, 263 m), Algeria. This analysis is carried out in order to investigate the power spectra behaviors of both temperature and wind speed and their variations with time. To determine the relationship between these two meteorological parameters, the cross wavelet analysis is also applied. The study is carried out using data extending over a period of four years. The analysis is applied over a frequency range from 0.002 to 0.5 cycles per day. The results show that significant synoptic oscillations of periods between 2 and 16 days occur mainly in the cold season in both wind and temperature time series. Those oscillations are characterized by short life durations of one to few weeks. Wavelet power spectrum has also revealed the presence of intra-seasonal oscillations of periods between 30 and 60 days. These intra-seasonal oscillations have been observed mainly in the warm seasons. This study reveals also that temperature and wind speed co-vary especially at the synoptic and the intra-seasonal frequencies. (author)

  15. Calibration Analysis Software for the ATLAS Pixel Detector

    CERN Document Server

    Stramaglia, Maria Elena; The ATLAS collaboration

    2015-01-01

    The calibration of the Pixel detector fulfills two main purposes: to tune front-end registers for establishing the best operational settings and to measure the tuning performance through a subset of scans. An analysis framework has been set up in order to take actions on the detector given the outcome of a calibration scan (e.g. to create a mask for disabling noisy pixels). The software framework to control all aspects of the Pixel detector scans and analyses is called Calibration Console. The introduction of a new layer, equipped with new Front End-I4 Chips, required an update the Console architecture. It now handles scans and scans analyses applied toghether to chips with dierent characteristics. An overview of the newly developed Calibration Analysis Software will be presented, together with some preliminary result.

  16. Atmospheric Stability Impacts on Power Curves of Tall Wind Turbines - An Analysis of a West Coast North American Wind Farm

    Energy Technology Data Exchange (ETDEWEB)

    Wharton, S; Lundquist, J K

    2010-02-22

    Tall wind turbines, with hub heights at 80 m or above, can extract large amounts of energy from the atmosphere because they are likely to encounter higher wind speeds, but they face challenges given the complex nature of wind flow and turbulence at these heights in the boundary layer. Depending on whether the boundary layer is stable, neutral, or convective, the mean wind speed, direction, and turbulence properties may vary greatly across the tall turbine swept area (40 to 120 m AGL). This variability can cause tall turbines to produce difference amounts of power during time periods with identical hub height wind speeds. Using meteorological and power generation data from a West Coast North American wind farm over a one-year period, our study synthesizes standard wind park observations, such as wind speed from turbine nacelles and sparse meteorological tower observations, with high-resolution profiles of wind speed and turbulence from a remote sensing platform, to quantify the impact of atmospheric stability on power output. We first compare approaches to defining atmospheric stability. The standard, limited, wind farm operations enable the calculation only of a wind shear exponent ({alpha}) or turbulence intensity (I{sub U}) from cup anemometers, while the presence at this wind farm of a SODAR enables the direct observation of turbulent kinetic energy (TKE) throughout the turbine rotor disk. Additionally, a nearby research meteorological station provided observations of the Obukhov length, L, a direct measure of atmospheric stability. In general, the stability parameters {alpha}, I{sub U}, and TKE are in high agreement with the more physically-robust L, with TKE exhibiting the best agreement with L. Using these metrics, data periods are segregated by stability class to investigate power performance dependencies. Power output at this wind farm is highly correlated with atmospheric stability during the spring and summer months, while atmospheric stability exerts

  17. 6 years of wind data for Marsabit, Kenya average over 14 m/s at 100 m hub height; An analysis of the wind energy potential

    Energy Technology Data Exchange (ETDEWEB)

    Kamau, J.N.; Kinyua, R. [Department of Physics, Jomo Kenyatta University of Agriculture and Technology, Nairobi (Kenya); Gathua, J.K. [Department of Physics, Kenyatta University, Nairobi (Kenya)

    2010-06-15

    The wind energy potential for generation of electricity and for domestic water pumping has been investigated for Marsabit, Kenya. Marsabit (37 58'N, 2 19'E) lies in Eastern province approximately 560 km from Nairobi. Wind data from the Kenya Meteorological department for the period 2001-2006 has been used to study the Diurnal, monthly and inter-annual variability using empirical methods including the Power law and Weibull statistics. Average wind speeds greater than11 m/s at a height of 10 m are prevalent in this area. The available power density at a height of 100 m is between 1776 W/m{sup 2} and 2202 W/m{sup 2} which is in the wind class range of 7 and 8. The maximum extractable power density at 100 m varied between 1417 W/m{sup 2} and 1757 W/m{sup 2}. Values of Weibull parameters k (dimensionless) and c (m/s) ranged between 2.5-3.05 and 11.86-12.97 respectively. Wind Rose analysis revealed no marked variation in wind direction and frequency throughout the year (mean direction between 150 and 160 degrees with highest standard deviation of 33.5 degrees). From the analysis, the site was found suitable for grid connected power generation and also for other stand-alone generators that can be used for water pumping and battery charging. (author)

  18. Bibliometric Analysis of International Collaboration in Wind and Solar Energy

    Directory of Open Access Journals (Sweden)

    Ichiro Sakata

    2013-09-01

    Full Text Available Modern technology is increasingly complex and demands an ever-widening range of knowledge and skills. No single country will possess all the knowledge and skills required for addressing global issues such as climate change. Technology collaboration between leading countries is important to promptly and efficiently address the problem. Previous studies have shown that a high level of collaboration is correlated with high paper productivity. This paper first aims to use objective data and create maps that enable us to see both the distribution of worldwide research competency and the relationship of international collaboration in clean energy research. In the international research network of wind power and solar cell, 4,189 institutions located in 121 countries and 6,600 institutions located in 125 countries are included respectively. This paper discusses various factors that would have an impact on research capability and support strong international relationships. With respect to research capability, governmental policies, stability of governmental commitment, natural conditions and historical and institutional differences have a significant impact on it. For research collaborations, factors such as geographical proximity, international science and technology policy, and developmental stage of technology have been brought to attention. This study demonstrates that bibliometrics is a methodology that is capable of providing a knowledge base that is useful in the development of the international science and technology policy and technological management strategy.

  19. Wind and Solar Resource Assessment of Sri Lanka and the Maldives (CD-ROM)

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.; Heimiller, D.; George, R.

    2003-08-01

    The Wind and Solar Resource Assessment of Sri Lanka and the Maldives CD contains an electronic version of Wind Energy Resource Atlas of Sri Lanka and the Maldives (NREL/TP-500-34518), Solar Resource Assessment for Sri Lanka and the Maldives (NREL/TO-710-34645), Sri Lanka Wind Farm Analysis and Site Selection Assistance (NREL/SR-500-34646), GIS Data Viewer (software and data files with a readme file), and Hourly Solar and Typical Meteorological Year Data with a readme file.

  20. Performance Analysis of Wind-Induced Piezoelectric Vibration Bimorph Cantilever for Rotating Machinery

    OpenAIRE

    Gongbo Zhou; Houlian Wang; Zhencai Zhu; Linghua Huang; Wei Li

    2015-01-01

    Harvesting the energy contained in the running environment of rotating machinery would be a good way to supplement energy to the wireless sensor. In this paper, we take piezoelectric bimorph cantilever beam with parallel connection mode as energy collector and analyze the factors which can influence the generation performance. First, a modal response theory model is built. Second, the static analysis, modal analysis, and piezoelectric harmonic response analysis of the wind-induced piezoelectr...

  1. Wind energy resource assessment in Madrid region

    Energy Technology Data Exchange (ETDEWEB)

    Migoya, Emilio; Crespo, Antonio; Jimenez, Angel; Garcia, Javier; Manuel, Fernando [Laboratorio de Mecanica de Fluidos, Departamento de Ingenieria Energetica y Fluidomecanica, Escuela Tecnica Superior Ingenieros Industriales (ETSII), Universidad Politecnica de Madrid (UPM), C/Jose Gutierrez Abascal, 2-28006, Madrid (Spain)

    2007-07-15

    The Comunidad Autonoma de Madrid (Autonomous Community of Madrid, in the following Madrid Region), is a region located at the geographical centre of the Iberian Peninsula. Its area is 8.028 km{sup 2}, and its population about five million people. The Department of Economy and Technological Innovation of the Madrid Region, together with some organizations dealing on energy saving and other research institutions have elaborated an Energy Plan for the 2004-12 period. As a part of this work, the Fluid Mechanics Laboratory of the Superior Technical School of Industrial Engineers of the Polytechnic University of Madrid has carried out the assessment of the wind energy resources [Crespo A, Migoya E, Gomez Elvira R. La energia eolica en Madrid. Potencialidad y prospectiva. Plan energetico de la Comunidad de Madrid, 2004-2012. Madrid: Comunidad Autonoma de Madrid; 2004]; using for this task the WAsP program (Wind Atlas Analysis and Application Program), and the own codes, UPMORO (code to study orography effects) and UPMPARK (code to study wake effects in wind parks). Different kinds of data have been collected about climate, topography, roughness of the land, environmentally protected areas, town and village distribution, population density, main facilities and electric power supply. The Spanish National Meteorological Institute has nine wind measurement stations in the region, but only four of them have good and reliable temporary wind data, with time measurement periods that are long enough to provide representative correlations among stations. The Observed Wind Climates of the valid meteorological stations have been made. The Wind Atlas and the resource grid have been calculated, especially in the high wind resource areas, selecting appropriate measurements stations and using criteria based on proximity, similarity and ruggedness index. Some areas cannot be used as a wind energy resource mainly because they have environmental regulation or, in some cases, are very close

  2. Wind Power Meteorology

    DEFF Research Database (Denmark)

    Lundtang Petersen, Erik; Mortensen, Niels Gylling; Landberg, Lars

    Wind power meteorology has evolved as an applied science, firmly founded on boundary-layer meteorology, but with strong links to climatology and geography. It concerns itself with three main areas: siting of wind turbines, regional wind resource assessment, and short-term prediction of the wind...... resource. The history, status and perspectives of wind power meteorology are presented, with emphasis on physical considerations and on its practical application. Following a global view of the wind resource, the elements of boundary layer meteorology which are most important for wind energy are reviewed......: wind profiles and shear, turbulence and gust, and extreme winds. The data used in wind power meteorology stem mainly from three sources: onsite wind measurements, the synoptic networks, and the re-analysis projects. Wind climate analysis, wind resource estimation and siting further require a detailed...

  3. Characterization of wind power resource in the United States

    Directory of Open Access Journals (Sweden)

    U. B. Gunturu

    2012-10-01

    Full Text Available Wind resource in the continental and offshore United States has been reconstructed and characterized using metrics that describe, apart from abundance, its availability, persistence and intermittency. The Modern Era Retrospective-Analysis for Research and Applications (MERRA boundary layer flux data has been used to construct wind profile at 50 m, 80 m, 100 m, 120 m turbine hub heights. The wind power density (WPD estimates at 50 m are qualitatively similar to those in the US wind atlas developed by the National Renewable Energy Laboratory (NREL, but quantitatively a class less in some regions, but are within the limits of uncertainty. The wind speeds at 80 m were quantitatively and qualitatively close to the NREL wind map. The possible reasons for overestimation by NREL have been discussed. For long tailed distributions like those of the WPD, the mean is an overestimation and median is suggested for summary representation of the wind resource.

    The impact of raising the wind turbine hub height on metrics of abundance, persistence, variability and intermittency is analyzed. There is a general increase in availability and abundance of wind resource but there is an increase in intermittency in terms of level crossing rate in low resource regions.

  4. ATLAS TV PROJECT

    CERN Multimedia

    OMNI communication

    2005-01-01

    CAMERA ON TOROID The ATLAS barrel toroid system consists of eight coils, each of axial length 25.3 m, assembled radially and symmetrically around the beam axis. The coils are of a flat racetrack type with two double-pancake windings made of 20.5 kA aluminium-stabilized niobium-titanium superconductor. The video is about the slow lowering of the toroid down to the cavern of ATLAS. It is very demanding task. The camera is placed on top of the toroid.

  5. Modal analysis of a grid-connected direct-drive permanent magnet synchronous generator wind turbine system

    DEFF Research Database (Denmark)

    Tan, Jin; Wang, Xiao Ru; Chen, Zhe

    2013-01-01

    In order to study the stability of a grid-connected direct-drive permanent magnet synchronous generator (PMSG) wind turbine systems, this paper presents the modal analysis of a PMSG wind turbine system. A PMSG model suitable for small signal stability analysis is presented. The modal properties...

  6. Policies and design elements for the repowering of wind farms: A qualitative analysis of different options

    Energy Technology Data Exchange (ETDEWEB)

    Rio, Pablo del, E-mail: pablo.delrio@cchs.csic.e [Consejo Superior de Investigaciones Cientificas, Calle Albasanz 26-28, Madrid 28037 (Spain); Calvo Silvosa, Anxo, E-mail: calvo@udc.e [Universidade da Coruna, Departamento de Economia Financeira e Contabilidade, Campus de Elvina s/n, A Coruna 15071 (Spain); Iglesias Gomez, Guillermo, E-mail: gwig@udc.e [Universidade da Coruna, Departamento de Economia Aplicada I, Campus de Elvina s/n, A Coruna 15071 (Spain)

    2011-04-15

    Repowering of a wind farm is the process of replacing existing wind turbines with new turbines that either have a larger nameplate capacity or more efficiency, resulting in a net increase of the power generated. Although repowering brings, both, social and private benefits, there are also several obstacles to repowering which justify public support. The aim of this paper is to provide an overview and a qualitative analysis of instruments and design options to support repowering of on-shore wind farms. The multicriteria analysis carried out in this paper shows that all instruments have their advantages and drawbacks. However, feed-in tariffs and investment subsidies seem to be particularly appropriate instruments in this regard. Furthermore, we provide an assessment of different design options to promote repowering according to key assessment criteria. The relevance of design elements hinges on the fact that these are the ones directly affecting the variables that are relevant in the decision to repower (capacity factors and investment costs). - Research highlights: {yields} This paper provides a qualitative analysis of instruments and design options to support repowering in wind farms. {yields} The multicriteria analysis has shown that all instruments have their advantages and drawbacks regarding promotion of repowering. {yields} However, feed-in tariffs and investment subsidies seem to be particularly appropriate instruments in this regard. {yields} The choice of design elements within instruments is at least as important to promote repowering as the choice of specific instruments.

  7. Failure Mode and Effect Analysis for Wind Turbine Systems in China

    DEFF Research Database (Denmark)

    Zhu, Jiangsheng; Ma, Kuichao; N. Soltani, Mohsen

    2017-01-01

    This paper discusses a cost based Failure Mode and Effect Analysis (FMEA) approch for the Wind Turbine (WT) with condition monitoring system in China. Normally, the traditional FMEA uses the Risk Priority Number (RPN) to rank failure modes. But the RPN can be changed with the Condition Monitoring...

  8. Cost-benefit analysis of hybrid wind-solar power generation by ...

    African Journals Online (AJOL)

    HOMER power optimization software for evaluation of design and performance of both off-grid and gridconnected power systems has been applied for cost-benefit analysis of a wind-solar hybrid power generation system. Comparison was also made with the cost per kilowatt of grid power supply. The hybrid system had a ...

  9. Hopf bifurcation and eigenvalue sensitivity analysis of doubly fed induction generator wind turbine system

    DEFF Research Database (Denmark)

    Yang, Li Hui; Xu, Zhao; Østergaard, Jacob

    2010-01-01

    This paper first presents the Hopf bifurcation analysis for a vector-controlled doubly fed induction generator (DFIG) which is widely used in wind power conversion systems. Using three-phase back-to-back pulse-width-modulated (PWM) converters, DFIG can keep stator frequency constant under variable...

  10. Hopf Bifurcation and Eigenvalue Sensitivity Analysis of Doubly Fed Induction Generator Wind Turbine System

    DEFF Research Database (Denmark)

    Yang, Lihui; Xu, Zhao; Østergaard, Jacob

    2009-01-01

    This paper first presents the Hopf bifurcation analysis for a vector-controlled doubly fed induction generator (DFIG) which is widely used in wind power conversion systems. Using three-phase back-to-back pulse-width-modulated (PWM) converters, DFIG can keep stator frequency constant under variable...

  11. Detection of icing on wind turbine blades by means of vibration and power curve analysis

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Kleani, Karolina; Mijatovic, Nenad

    2016-01-01

    accelerometers and power performance analysis. Features extracted from these two techniques serve as inputs in a decision-making scheme, allowing early activation of de-icing systems or shut down of the wind turbine. An additional parameter is the month of operation, assuring consistent outcomes in both winter...

  12. Using rotor or tip speed in the acoustical analysis of small wind turbines

    Science.gov (United States)

    Acoustical noise data have been collected and analyzed on small wind turbines used for water pumping at the USDA-ARS Conservation and Production Research Laboratory (CPRL) near Bushland, Texas. This acoustical analysis differed from previous research in that the data were analyzed with rotor or tip ...

  13. Power Grid Modelling From Wind Turbine Perspective Using Principal Componenet Analysis

    DEFF Research Database (Denmark)

    Farajzadehbibalan, Saber; Ramezani, Mohammad Hossein; Nielsen, Peter

    2015-01-01

    In this study, we derive an eigenvector-based multivariate model of a power grid from the wind farm's standpoint using dynamic principal component analysis (DPCA). The main advantages of our model over previously developed models are being more realistic and having low complexity. We show that th...

  14. Incorporation of wind generation to the Mexican power grid: Steady state analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tovar, J.H.; Guardado, J.L.; Cisneros, F. [Inst. Tecnologico de Morelia (Mexico); Cadenas, R.; Lopez, S. [Comision Federal de Electricidad, Morelia (Mexico)

    1997-09-01

    This paper describes a steady state analysis related with the incorporation of large amounts of eolic generation into the Mexican power system. An equivalent node is used to represent individual eolic generators in the wind farm. Possible overloads, losses, voltage and reactive profiles and estimated severe contingencies are analyzed. Finally, the conclusions of this study are presented.

  15. Analysis and control of the compaction force in the composite prepreg tape winding process for rocket motor nozzles

    Directory of Open Access Journals (Sweden)

    Xiaodong He

    2017-04-01

    Full Text Available In the process of composite prepreg tape winding, the compaction force could influence the quality of winding products. According to the analysis and experiments, during the winding process of a rocket motor nozzle aft exit cone with a winding angle, there would be an error between the deposition speed of tape layers and the feeding speed of the compaction roller, which could influence the compaction force. Both a lack of compaction and overcompaction related to the feeding of the compaction roller could result in defects of winding nozzles. Thus, a flexible winding system has been developed for rocket motor nozzle winding. In the system, feeding of the compaction roller could be adjusted in real time to achieve an invariable compaction force. According to experiments, the force deformation model of the winding tape is a time-varying system. Thus, a forgetting factor recursive least square based parameter estimation proportional-integral-differential (PID controller has been developed, which could estimate the time-varying parameter and control the compaction force by adjusting the feeding of the compaction roller during the winding process. According to the experimental results, a winding nozzle with fewer voids and a smooth surface could be wounded by the invariable compaction force in the flexible winding system.

  16. Time Series Analysis and Forecasting for Wind Speeds Using Support Vector Regression Coupled with Artificial Intelligent Algorithms

    Directory of Open Access Journals (Sweden)

    Ping Jiang

    2015-01-01

    Full Text Available Wind speed/power has received increasing attention around the earth due to its renewable nature as well as environmental friendliness. With the global installed wind power capacity rapidly increasing, wind industry is growing into a large-scale business. Reliable short-term wind speed forecasts play a practical and crucial role in wind energy conversion systems, such as the dynamic control of wind turbines and power system scheduling. In this paper, an intelligent hybrid model for short-term wind speed prediction is examined; the model is based on cross correlation (CC analysis and a support vector regression (SVR model that is coupled with brainstorm optimization (BSO and cuckoo search (CS algorithms, which are successfully utilized for parameter determination. The proposed hybrid models were used to forecast short-term wind speeds collected from four wind turbines located on a wind farm in China. The forecasting results demonstrate that the intelligent hybrid models outperform single models for short-term wind speed forecasting, which mainly results from the superiority of BSO and CS for parameter optimization.

  17. Hadronic triggers and trigger object-level analysis at ATLAS

    CERN Document Server

    Zaripovas, Donatas Ramilas; The ATLAS collaboration

    2017-01-01

    Hadronic signatures are critical to the high energy physics analysis program at the Large Hadron Collider (LHC), and are broadly used for both Standard Model measurements and searches for new physics. These signatures include generic quark and gluon jets, as well as jets originating from b-quarks or the decay of massive particles (such as electroweak bosons or top quarks). Additionally missing transverse momentum from non-interacting particles provides an interesting probe in the search for new physics beyond the Standard Model. Developing trigger selections that target these events is a huge challenge at the LHC due to the enormous event rates associated with these signatures. This challenge is exacerbated by the amount of pile-up activity, which continues to grow. In order to address these challenges, several new techniques have been developed during the past year in order to significantly improve the potential of the 2017 dataset and overcome the limiting factors, such as storage and computing requirements...

  18. Indexing of ATLAS data management and analysis system metadata

    CERN Document Server

    Grigoryeva, Maria; The ATLAS collaboration

    2017-01-01

    This manuscript is devoted to the development of the system to manage metainformation of modern HENP experiments. The main purpose of the system is to provide scientists with transparent access to the actual and historical metadata related to data analysis, processing and modeling. The system design addresses the following goals : providing a flexible and fast search for metadata on various combinations of keywords, generating aggregated reports, categorized according to selected parameters, such as the studied physical process, scientific topic, physical group, etc. The article presents the architecture of the developed indexing and search system, as well as the results of performance tests. The comparison of the query execution speed within the developed system and in case of querying the original relational databases showed that the developed system provides results faster. Also the new system allows much more complex search requests, than the original storages.

  19. Hadronic Triggers and trigger-object level analysis at ATLAS

    CERN Document Server

    Zaripovas, Donatas Ramilas; The ATLAS collaboration

    2017-01-01

    Hadronic signatures are critical to the high energy physics analysis program, and are broadly used for both Standard Model measurements and searches for new physics. These signatures include generic quark and gluon jets, as well as jets originating from b-quarks or the decay of massive particles (such as electroweak bosons or top quarks). Additionally missing transverse momentum from non-interacting particles provides an interesting probe in the search for new physics beyond the Standard Model. Developing trigger selections that target these events is a huge challenge at the LHC due to the enormous rates associated with these signatures. This challenge is exacerbated by the amount of pile-up activity, which continues to grow. In order to address these challenges, several new techniques have been developed during the past year in order to significantly improve the potential of the 2017 dataset and overcome the limiting factors to more deeply probing for new physics, such as storage and computing requirements f...

  20. Gust response analysis and wind tunnel test for a high-aspect ratio wing

    Directory of Open Access Journals (Sweden)

    Liu Yi

    2016-02-01

    Full Text Available A theoretical nonlinear aeroelastic response analysis for a flexible high-aspect ratio wing excited by harmonic gust load is presented along with a companion wind tunnel test. A multidisciplinary coupled numerical calculation is developed to simulate the flexible model wing undergoing gust load in the time domain via discrete nonlinear finite element structural dynamic analysis and nonplanar unsteady vortex lattice aerodynamic computation. A dynamic perturbation analysis about a nonlinear static equilibrium is also used to determine the small perturbation flutter boundary. A novel noncontact 3-D camera measurement analysis system is firstly used in the wind tunnel test to obtain the spatial large deformation and responses. The responses of the flexible wing under different static equilibrium states and frequency gust loads are discussed. The fair to good quantitative agreements between the theoretical and experimental results demonstrate that the presented analysis method is an acceptable way to predict the geometrically nonlinear gust response for flexible wings.

  1. Bifurcation analysis of the transition of dune shapes under a unidirectional wind.

    Science.gov (United States)

    Niiya, Hirofumi; Awazu, Akinori; Nishimori, Hiraku

    2012-04-13

    A bifurcation analysis of dune shape transition is made. By use of a reduced model of dune morphodynamics, the Dune Skeleton model, we elucidate the transition mechanism between different shapes of dunes under unidirectional wind. It was found that the decrease in the total amount of sand in the system and/or the lateral sand flow shifts the stable state from a straight transverse dune to a wavy transverse dune through a pitchfork bifurcation. A further decrease causes wavy transverse dunes to shift into barchans through a Hopf bifurcation. These bifurcation structures reveal the transition mechanism of dune shapes under unidirectional wind.

  2. Analysis of wind turbine aerodynamics and aeroelasticity using vortex-based methods

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre

    Momentum analysis through Blade Element Momentum (BEM) and Computational Fluid Dynamics (CFD) are the two major paths commonly followed for wind turbine aerodynamic and aeroelastic research. Instead, the current PhD thesis focuses on the application of vortex-based methods. Vortex-based methods...... to be used in BEM implementations. The current thesis also presents the implementation of a vortex code to further investigate wind turbine aerodynamics. The code consists of both low-order and high-order formulations. The implementation features are described and illustrated through different validation...

  3. Wind characteristics on the Yucatan Peninsula based on short term data from meteorological stations

    Energy Technology Data Exchange (ETDEWEB)

    Soler-Bientz, Rolando [CREST, Department of Electronic and Electrical Engineering, Loughborough University, LE11 3TU (United Kingdom); Energy Laboratory, Faculty of Engineering, Autonomous University of Yucatan, Merida, Yucatan (Mexico); Watson, Simon [CREST, Department of Electronic and Electrical Engineering, Loughborough University, LE11 3TU (United Kingdom); Infield, David [Institute of Energy and Environment, University of Strathclyde, Glasgow (United Kingdom)

    2010-04-15

    Due to the availability of sparsely populated and flat open terrain, the Yucatan Peninsula located in eastern Mexico is a promising region from the perspective of wind energy development. Study of the diurnal and seasonal wind resource is an important stage in the move towards commercial exploitation of wind power in this Latin American region. An analysis of the characteristics of the wind resource of the Yucatan Peninsula is presented in this paper, based on 10 min averaged wind speed data from nine meteorological stations, between 2000 and 2007. Hourly and monthly patterns of the main environmental parameters have been examined. Highly directional behaviour was identified that reflects the influence of winds coming from the Caribbean Sea and the Gulf of Mexico. The characteristics of the wind speed variation observed at the studied sites reflected their proximity to the coast and whether they were influenced by wind coming predominantly from over the land or predominantly from over the sea. The atmospheric stability over the eastern seas of the Yucatan Peninsula was also analysed to assess thermal effects for different wind directions. The findings were consistent with the variation in average wind speeds observed at the coastal sites where winds came predominantly from over the sea. The research presented here is to be used as a basis for a wind atlas for the Yucatan Peninsula. (author)

  4. Scope of wind energy in Bangladesh and simulation analysis of three different horizontal axis wind turbine blade shapes

    Science.gov (United States)

    Khan, Md. Arif-Ul Islam; Das, Swapnil; Dey, Saikat

    2017-12-01

    : Economic growth and energy demand are intertwined. Therefore, one of the most important concerns of the government and in the world is the need for energy security. Currently, the world relies on coal, crude oil and natural gas for energy generati on. However, the energy crisis together with climate change and depletion of oil have become major concerns to all countries. Therefore, alternative energy resources such as wind energy attracted interest from both public and private sectors to invest in energy generation from this source extensively. Both Vertical and Horizontal axis wind turbine can be used for this purpose. But, Horizontal axis is the most promising between them due to its efficiency and low expense. Bangladesh being a tropical country does have a lot of wind flow at different seasons of the year. However, there are some windy locations in which wind energy projects could be feasible. In this project a detailed review of the current st ate-of-art for wind turbine blade design is presented including theoretical maximum efficiency, Horizontal Axis Wind Turbine (HAWT) blade design, simulation power and COP values for different blade material. By studying previously collected data on the wind resources available in B angladesh at present and by analyzing this data, this paper will discuss the scope of wind energy in Bangladesh.

  5. Sensitivity analysis of nacelle lidar free stream wind speed measurements to wind-induction reconstruction model and lidar range configuration

    DEFF Research Database (Denmark)

    Svensson, Elin; Borraccino, Antoine; Meyer Forsting, Alexander Raul

    The sensitivity of nacelle lidar wind speed measurements to wind-induction models and lidar range configurations is studied using experimental data from the Nørrekær Enge (NKE) measurement campaign and simulated lidar data from Reynold-Averaged Navier Stokes (RANS) aerodynamic computational fluid...

  6. Noise Model Analysis and Estimation of Effect due to Wind Driven Ambient Noise in Shallow Water

    Directory of Open Access Journals (Sweden)

    S. Sakthivel Murugan

    2011-01-01

    Full Text Available Signal transmission in ocean using water as a channel is a challenging process due to attenuation, spreading, reverberation, absorption, and so forth, apart from the contribution of acoustic signals due to ambient noises. Ambient noises in sea are of two types: manmade (shipping, aircraft over the sea, motor on boat, etc. and natural (rain, wind, seismic, etc., apart from marine mammals and phytoplanktons. Since wind exists in all places and at all time: its effect plays a major role. Hence, in this paper, we concentrate on estimating the effects of wind. Seven sets of data with various wind speeds ranging from 2.11 m/s to 6.57 m/s were used. The analysis is performed for frequencies ranging from 100 Hz to 8 kHz. It is found that a linear relationship between noise spectrum and wind speed exists for the entire frequency range. Further, we developed a noise model for analyzing the noise level. The results of the empirical data are found to fit with results obtained with the aid of noise model.

  7. Analysis of the grid connection sequence of stall- and pitch-controlled wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Quinonez-Varela, G.; Cruden, A.; Anaya-Lara, O.; Tumilty, R.; McDonald, J.R. [Univ. of Strathclyde, Inst. for Energy and Environment (United Kingdom)

    2007-11-15

    The realistic modelling of wind turbines and wind farms is crucial in any form of power system analysis, and consequently, knowledge about their electrical characteristics and performance is also vital. One of the operating conditions producing major transient interaction between a wind turbine generator and the local grid is the grid connection sequence itself, which is particularly significant in fixed-speed turbines. This paper presents experimental measurements of the grid connection sequence of both types of fixed speed wind turbines, i.e. stall- and pitch-controlled via a soft-start device performed at two existing wind farms. Some of the results evidenced significant discrepancies between the actual soft-start operating intervals and those stated/suggested by open literature. The discussion of the paper focuses on highlighting the importance of accurate modelling of the grid connection sequence in order to avoid erroneous estimations of the interaction between the turbine and the grid during this operating state, or inappropriate design of the grid connection. (au)

  8. Dynamic stall analysis of horizontal-axis-wind-turbine blades using computational fluid dynamics

    Science.gov (United States)

    Sayed, Mohamed A.; Kandil, Hamdy A.; Morgan, El-Sayed I.

    2012-06-01

    Dynamic stall has been widely known to significantly affect the performance of the wind turbines. In this paper, aerodynamic simulation of the unsteady low-speed flow past two-dimensional wind turbine blade profiles, developed by the National Renewable Energy Laboratory (NREL), will be performed. The aerodynamic simulation will be performed using Computational Fluid Dynamics (CFD). The governing equations used in the simulations are the Unsteady-Reynolds-Averaged-Navier-Stokes (URANS) equations. The unsteady separated turbulent flow around an oscillating airfoil pitching in a sinusoidal pattern in the regime of low Reynolds number is investigated numerically. The investigation employs the URANS approach with the most suitable turbulence model. The development of the light dynamic stall of the blades under consideration is studied. The S809 blade profile is simulated at different mean wind speeds. Moreover, the S826 blade profile is also considered for analysis of wind turbine blade which is the most suitable blade profile for the wind conditions in Egypt over the site of Gulf of El-Zayt. In order to find the best oscillating frequency, different oscillating frequencies are studied. The best frequency can then be used for the blade pitch controller. The comparisons with the experimental results showed that the used CFD code can accurately predict the blade profile unsteady aerodynamic loads.

  9. Flexible dynamic analysis of an offshore wind turbine installed on a floating spar platform

    Directory of Open Access Journals (Sweden)

    Xiangqian Zhu

    2016-05-01

    Full Text Available Flexible dynamic analysis is a critical process in designing offshore wind turbines that are composed of several huge components. This process was implemented with a hybrid method of finite element multibody system using commercial software in this article. Based on this method, the tower and blades were modeled as flexible components using three-dimensional solid elements. The effect of flexible deformation of the tower and blades on the global motions of the floating wind turbine was investigated by comparing the simulation results from the flexible body modeling with those from the rigid body modeling. The tower, blades, and spar platform were divided into sections according to the geometry configuration of the 5-MW OC3-Hywind floating wind turbine. The time- and position-dependent loads, coming from the wind, wave, and mooring system, were expressed approximately with respect to the divided sections. The relationships between the global motions and the external loads were studied, which indicated that the wind loads had dominant influences on the translational motions and the rotational motions were mainly generated by the propagating waves.

  10. Harmonic Stability Analysis of Offshore Wind Farm with Component Connection Method

    DEFF Research Database (Denmark)

    Hou, Peng; Ebrahimzadeh, Esmaeil; Wang, Xiongfei

    2017-01-01

    In this paper, an eigenvalue-based harmonic stability analysis method for offshore wind farm is proposed. Considering the internal cable connection layout, a component connection method (CCM) is adopted to divide the system into individual blocks as current controller of converters, LCL filters......, this method is superior in reducing the computational cost. A 4 by 4 wind turbines wind farm is selected as the study case and the proposed method is validated by comparing the results obtained from time domain simulation software — Power System Computer Aided Design (PSCAD)......., collection system cable impedance, transmission cable impedance and grid impedance. By using this method, each block can be modelled independently and then be integrated into a whole state space matrix which contains sparse and diagonal matrix. Compared with the traditional state space formulation process...

  11. Installation Of 2MW Wind Power Plant In Northern Cyprus Technical Economical And Environmental Analysis

    Directory of Open Access Journals (Sweden)

    Aliyu Aliyu

    2017-11-01

    Full Text Available The impetus for the work presented here arose from the fact that the demand for renewable energy grows and the supply of the non-renewable energy is at the decreasing level. An increasing percentage of total energy produced globally is moving to renewable forms. Wind energy enjoys increasing deployment for power generation due to the economic benefits associated with it.Turkish Republic of Northern Cyprus TRNC has abundance of renewable energy it has an average wind speed of 4.30ms and 5.04ms at 10m and 50m respectively. The economic analysis of is plant shows that the wind farm has an investment cost of 2300000 with 333217.8 as annual savings. The simple payback was calculated to be 7 years the savings to investment ratio was found to be 3.62 the net present value turn to be positive while the return on investment was 14.48.

  12. Reliability analysis and risk-based methods for planning of operation & maintenance of offshore wind turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2017-01-01

    Reliability analysis and probabilistic models for wind turbines are considered with special focus on structural components and application for reliability-based calibration of partial safety factors. The main design load cases to be considered in design of wind turbine components are presented...... for extreme and fatigue limit states are presented. Operation & Maintenance planning often follows corrective and preventive strategies based on information from condition monitoring and structural health monitoring systems. A reliability- and riskbased approach is presented where a life-cycle approach...... including the effects of the control system and possible faults due to failure of electrical / mechanical components. Considerations are presented on the target reliability level for wind turbine structural components. Application is shown for reliability-based calibrations of partial safety factors...

  13. Analysis of wind driven self-excited induction generator supplying isolated DC loads

    Directory of Open Access Journals (Sweden)

    Khaled S. Sakkoury

    2017-05-01

    Full Text Available This paper presents the analysis, modelling and simulation of wind-driven self-excited induction generator (SEIG. The three-phase SEIG is driven by a variable-speed prime mover to represent a wind turbine. Also, the paper investigates the dynamic performance of the SEIG during start-up, increasing or decreasing the load or rotor speed. The value of the excitation capacitance required for the SEIG is calculated to give suitable saturation level to assure self-excitation and to avoid heavy saturation levels. Matching of the maximum power available from the wind turbine is performed through varying the load value. The effect of AC–DC power conversion on the generator is investigated. The system simulation is carried out using MATLAB/SIMULINK toolbox program.

  14. Oscillation mode analysis considering the interaction between a DFIG-based wind turbine and the grid

    Science.gov (United States)

    Wu, Wangping; Xie, Da; Lu, Yupu; Zhao, Zuyi; Yu, Songtao

    2017-01-01

    Sub-synchronous interactions between wind farms and transmission networks with series compensation have drawn great attention. As most large wind farms in Europe and Asia employ doubly fed induction generator turbines, there has recently been a growing interest in studying this phenomenon. To study the stability of wind turbine with doubly fed induction generator after a small disturbance, a complete small signal system is built in this paper. By using eigenvalue and participation factor analysis, the relation between the modes and state variables can be discovered. Thereafter, the oscillation modes are classified into electrical resonance, sub-synchronous resonance, sub-synchronous oscillation, sub-synchronous control interaction, and low frequency oscillation. To verify the oscillation frequency of each oscillation mode, time-domain simulation based on MATLAB/Simulink is presented. The simulation results justify the effectiveness of the small-signal models.

  15. Analysis of ATLAS 6-inch cold leg break simulation with MARS-KS code

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Se Yun; Jun, Hwang Yong; Ha, Sang Jun [Korea Electric Power Company, Daejeon (Korea, Republic of)

    2011-05-15

    A Domestic Standard Problem (DSP) exercise using ATLAS facility has been organized by KAERI. As the second DSP exercise, the 6-inch cold leg bottom break was determined. This experiment is the counterpart test to the DVI line break to verify the safety performance of the DVI method over the traditional CLI method. Compared with the large break LOCA, the phases of the small break LOCA prior to core recovery occur over a long period. The blowdown, natural circulation, loop seal clearance, boil-off, and core recovery phase should be investigated minutely with relevant models of safety analysis codes in order to predict these thermal hydraulic phenomena correctly. To investigate the ECC bypass phenomena, a finer study on the thermalhydraulic behavior in upper annulus downcomer was carried out

  16. Thermal analysis of the airflow around ATLAS muon barrel in view of the active ventilation conditions

    CERN Document Server

    Vila-Nova-Goncalves, L

    2004-01-01

    A thermal analysis of the airflow around the ATLAS muon detector, taking into consideration the real ventilation state of affairs inside the UX15 cavern and the electronic equipment disseminated in the region of the muon chambers (which leads to the development of temperature gradients in the air surrounding the detector), is presented. Thorough studies on a 2D model of the structure and its variants were elaborated by means of a CFD (Computational Fluid Dynamics) code and the most significant results are shown via the temperature and velocity charts available in the final sections of the current report. The first two sections furnish a synopsis of the structural components and the objectives of the study; the third illustrates the parameters of study and the fourth and fifth sections are devoted to the model and the results of the simulations.

  17. Coupled analysis of multi-impact energy harvesting from low-frequency wind induced vibrations

    Science.gov (United States)

    Zhu, Jin; Zhang, Wei

    2015-04-01

    Energy need from off-grid locations has been critical for effective real-time monitoring and control to ensure structural safety and reliability. To harvest energy from ambient environments, the piezoelectric-based energy-harvesting system has been proven very efficient to convert high frequency vibrations into usable electrical energy. However, due to the low frequency nature of the vibrations of civil infrastructures, such as those induced from vehicle impacts, wind, and waves, the application of a traditional piezoelectric-based energy-harvesting system is greatly restrained since the output power drops dramatically with the reduction of vibration frequencies. This paper focuses on the coupled analysis of a proposed piezoelectric multi-impact wind-energy-harvesting device that can effectively up-convert low frequency wind-induced vibrations into high frequency ones. The device consists of an H-shape beam and four bimorph piezoelectric cantilever beams. The H-shape beam, which can be easily triggered to vibrate at a low wind speed, is originated from the first Tacoma Narrows Bridge, which failed at wind speeds of 18.8 m s-1 in 1940. The multi-impact mechanism between the H-shape beam and the bimorph piezoelectric cantilever beams is incorporated to improve the harvesting performance at lower frequencies. During the multi-impact process, a series of sequential impacts between the H-shape beam and the cantilever beams can trigger high frequency vibrations of the cantilever beams and result in high output power with a considerably high efficiency. In the coupled analysis, the coupled structural, aerodynamic, and electrical equations are solved to obtain the dynamic response and the power output of the proposed harvesting device. A parametric study for several parameters in the coupled analysis framework is carried out including the external resistance, wind speed, and the configuration of the H-shape beam. The average harvested power for the piezoelectric cantilever

  18. Exploring JavaScript and ROOT technologies to create Web-based ATLAS analysis and monitoring tools

    CERN Document Server

    Pineda, A S

    2015-01-01

    We explore the potential of current web applications to create online interfaces that allow the visualization, interaction and real cut-based physics analysis and monitoring of processes through a web browser. The project consists in the initial development of web- based and cloud computing services to allow students and researchers to perform fast and very useful cut-based analysis on a browser, reading and using real data and official Monte- Carlo simulations stored in ATLAS computing facilities. Several tools are considered: ROOT, JavaScript and HTML. Our study case is the current cut-based H → ZZ → llqq analysis of the ATLAS experiment. Preliminary but satisfactory results have been obtained online.

  19. Exploring JavaScript and ROOT technologies to create Web-based ATLAS analysis and monitoring tools

    Science.gov (United States)

    Sánchez Pineda, A.

    2015-12-01

    We explore the potential of current web applications to create online interfaces that allow the visualization, interaction and real cut-based physics analysis and monitoring of processes through a web browser. The project consists in the initial development of web- based and cloud computing services to allow students and researchers to perform fast and very useful cut-based analysis on a browser, reading and using real data and official Monte- Carlo simulations stored in ATLAS computing facilities. Several tools are considered: ROOT, JavaScript and HTML. Our study case is the current cut-based H → ZZ → llqq analysis of the ATLAS experiment. Preliminary but satisfactory results have been obtained online.

  20. On-line analysis capabilities developed to support the AFW wind-tunnel tests

    Science.gov (United States)

    Wieseman, Carol D.; Hoadley, Sherwood T.; Mcgraw, Sandra M.

    1992-01-01

    A variety of on-line analysis tools were developed to support two active flexible wing (AFW) wind-tunnel tests. These tools were developed to verify control law execution, to satisfy analysis requirements of the control law designers, to provide measures of system stability in a real-time environment, and to provide project managers with a quantitative measure of controller performance. Descriptions and purposes of the developed capabilities are presented along with examples. Procedures for saving and transferring data for near real-time analysis, and descriptions of the corresponding data interface programs are also presented. The on-line analysis tools worked well before, during, and after the wind tunnel test and proved to be a vital and important part of the entire test effort.

  1. Analysis of Upper Air, Ground and Remote Sensing Data for the Atlas Field Campaign in San Juan, Puerto Rico

    Science.gov (United States)

    Gonzalez-Cruz, Jorge E.

    2005-01-01

    The general climate of the island of Puerto Rico is dominated by the easterly trade winds from the Atlantic Ocean, and during synoptically calm days by the topographic and local land surface characteristics [1]. The urban canopy of the metropolitan area of San Juan, capital city of the Island, may introduce a new microclimate that changes the characteristics of the low atmosphere and interacts with the other microclimates already present in the island. The primitive land cover and land use (LCLU) of the metropolitan area of San Juan was composed by broadleaf trees, moist soils, and very dense vegetation in general. The urban LCLU changes the balance for the mass, momentum and energy between the bottom boundary and the lower atmosphere, creating different climate conditions over urban and rural regions. Some of these differences are low relative humidity and high temperatures observed in urban areas when compared to rural areas. These in turn produces a convective circulation over the urban areas, a phenomenon compared to the sea and land breezes, commonly known as heat islands (UHI). Factors that contribute to the formation of the UHI are anthropogenic heat sources, aerosols from pollutants, fast water canalization due to the presence of buildings and streets, among others. The comparison between urban and rural climates is the most common approach to analyze the UHI. These contrasts are larger in clear and calm conditions and tend to disappear in cloudy and windy weather. The UHI was recognized in the early 1950 s as closed isotherms that separates the city from the general temperature field [2]. The impact of the urban LCLU in San Juan, Puerto Rico, was quantified calculating the difference between historical data sets for the air temperature over an identified urban area and a rural area dT(U-R). The analysis of the climatological data revealed that a UHI exists in the metropolitan area of San Juan, Puerto Rico. The data reveals a permanent urban heat island

  2. Technoeconomic analysis of different options for the production of hydrogen from sunlight, wind, and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.K.; Spath, P.L.; Amos, W.A. [National Renewable Energy Lab., Golden, CO (United States)

    1998-08-01

    To determine their technical and economic viability and to provide insight into where each technology is in its development cycle, different options to produce hydrogen from sunlight, wind, and biomass were studied. Additionally, costs for storing and transporting hydrogen were determined for different hydrogen quantities and storage times. The analysis of hydrogen from sunlight examined the selling price of hydrogen from two technologies: direct photoelectrochemical (PEC) conversion of sunlight and photovoltaic (PV)-generated electricity production followed by electrolysis. The wind analysis was based on wind-generated electricity production followed by electrolysis. In addition to the base case analyses, which assume that hydrogen is the sole product, three alternative scenarios explore the economic impact of integrating the PV- and wind-based systems with the electric utility grid. Results show that PEC hydrogen production has the potential to be economically feasible. Additionally, the economics of the PV and wind electrolysis systems are improved by interaction with the grid. The analysis of hydrogen from biomass focused on three gasification technologies. The systems are: low pressure, indirectly-heated gasification followed by steam reforming; high pressure, oxygen-blown gasification followed by steam reforming; and pyrolysis followed by partial oxidation. For each of the systems studied, the downstream process steps include shift conversion followed by hydrogen purification. Only the low pressure system produces hydrogen within the range of the current industry selling prices (typically $0.7--$2/kg, or $5--14/GJ on a HHV basis). A sensitivity analysis showed that, for the other two systems, in order to bring the hydrogen selling price down to $2/kg, negative-priced feedstocks would be required.

  3. Mod 1 wind turbine generator failure modes and effects analysis

    Science.gov (United States)

    1979-01-01

    A failure modes and effects analysis (FMEA) was directed primarily at identifying those critical failure modes that would be hazardous to life or would result in major damage to the system. Each subsystem was approached from the top down, and broken down to successive lower levels where it appeared that the criticality of the failure mode warranted more detail analysis. The results were reviewed by specialists from outside the Mod 1 program, and corrective action taken wherever recommended.

  4. ATLAS Recordings

    CERN Multimedia

    Steven Goldfarb; Mitch McLachlan; Homer A. Neal

    Web Archives of ATLAS Plenary Sessions, Workshops, Meetings, and Tutorials from 2005 until this past month are available via the University of Michigan portal here. Most recent additions include the Trigger-Aware Analysis Tutorial by Monika Wielers on March 23 and the ROOT Workshop held at CERN on March 26-27.Viewing requires a standard web browser with RealPlayer plug-in (included in most browsers automatically) and works on any major platform. Lectures can be viewed directly over the web or downloaded locally.In addition, you will find access to a variety of general tutorials and events via the portal.Feedback WelcomeOur group is making arrangements now to record plenary sessions, tutorials, and other important ATLAS events for 2007. Your suggestions for potential recording, as well as your feedback on existing archives is always welcome. Please contact us at wlap@umich.edu. Thank you.Enjoy the Lectures!

  5. Seismic response of a full-scale wind turbine tower using experimental and numerical modal analysis

    Science.gov (United States)

    Kandil, Kamel Sayed Ahmad; Saudi, Ghada N.; Eltaly, Boshra Aboul-Anen; El-khier, Mostafa Mahmoud Abo

    2016-12-01

    Wind turbine technology has developed tremendously over the past years. In Egypt, the Zafarana wind farm is currently generating at a capacity of 517 MW, making it one of the largest onshore wind farms in the world. It is located in an active seismic zone along the west side of the Gulf of Suez. Accordingly, seismic risk assessment is demanded for studying the structural integrity of wind towers under expected seismic hazard events. In the context of ongoing joint Egypt-US research project "Seismic Risk Assessment of Wind Turbine Towers in Zafarana wind Farm Egypt" (Project ID: 4588), this paper describes the dynamic performance investigation of an existing Nordex N43 wind turbine tower. Both experimental and numerical work are illustrated explaining the methodology adopted to investigate the dynamic behavior of the tower under seismic load. Field dynamic testing of the full-scale tower was performed using ambient vibration techniques (AVT). Both frequency domain and time domain methods were utilized to identify the actual dynamic properties of the tower as built in the site. Mainly, the natural frequencies, their corresponding mode shapes and damping ratios of the tower were successfully identified using AVT. A vibration-based finite element model (FEM) was constructed using ANSYS V.12 software. The numerical and experimental results of modal analysis were both compared for matching purpose. Using different simulation considerations, the initial FEM was updated to finally match the experimental results with good agreement. Using the final updated FEM, the response of the tower under the AQABA earthquake excitation was investigated. Time history analysis was conducted to define the seismic response of the tower in terms of the structural stresses and displacements. This work is considered as one of the pioneer structural studies of the wind turbine towers in Egypt. Identification of the actual dynamic properties of the existing tower was successfully performed

  6. Analysis of Near Simultaneous Jimsphere and AMPS High Resolution Wind Profiles

    Science.gov (United States)

    Adelfang, S. I.

    2003-01-01

    The high-resolution wind profile of the Automated Meteorological Profiling System (HRAMPS) is the proposed replacement for the Jimsphere measurement system used to support NASA Shuttle launches from the Eastern Test Range (ETR). Samples of twenty-six ETR near simultaneous Jimsphere and HRAMPS wind profiles were obtained for Shuttle program HRAMPS certification studies. Shuttle systems engineering certification is to ensure that spacecraft and launch vehicle systems performance and safety evaluations for each launch (derived from flight simulations with Jimsphere wind profile data bases) retain their validity when HRAMPS profiles are used on day-of-launch (DOL) in trajectory and loads simulations to support the commit-to-launch decision. This paper describes a statistical analysis of the near simultaneous profiles. In principle the differences between a Jimsphere profile and an HRAMPS profile should be attributed to tracking technology (radar versus GPS tracking of a Jimsphere flight element) and the method for derivation of wind vectors from the raw tracking data. In reality, it is not technically feasible to track the same Jimsphere balloon with the two systems. The aluminized Mylar surface of the standard Jimsphere flight element facilitates radar tracking, but it interferes with HRAMPS during simultaneous tracking. Suspending a radar reflector from an HRAMPS flight element (Jimsphere without aluminized coating) does not produce satisfactory Jimsphere profiles because of intermittent radar returns. Thus, differences between the Jimsphere and HRAMPS profiles are also attributed to differences in the trajectories of separate flight elements. Because of small sample size and a test period limited to one winter season, test measurements during extreme high winds aloft could not have been expected and did not occur. It is during the highest winds that the largest differences between Jimsphere and HRAMPS would occur because the distance between flight elements would be

  7. Wind effect on PV module temperature: Analysis of different techniques for an accurate estimation.

    Science.gov (United States)

    Schwingshackl, Clemens; Petitta, Marcello; Ernst Wagner, Jochen; Belluardo, Giorgio; Moser, David; Castelli, Mariapina; Zebisch, Marc; Tetzlaff, Anke

    2013-04-01

    In this abstract a study on the influence of wind to model the PV module temperature is presented. This study is carried out in the framework of the PV-Alps INTERREG project in which the potential of different photovoltaic technologies is analysed for alpine regions. The PV module temperature depends on different parameters, such as ambient temperature, irradiance, wind speed and PV technology [1]. In most models, a very simple approach is used, where the PV module temperature is calculated from NOCT (nominal operating cell temperature), ambient temperature and irradiance alone [2]. In this study the influence of wind speed on the PV module temperature was investigated. First, different approaches suggested by various authors were tested [1], [2], [3], [4], [5]. For our analysis, temperature, irradiance and wind data from a PV test facility at the airport Bolzano (South Tyrol, Italy) from the EURAC Institute of Renewable Energies were used. The PV module temperature was calculated with different models and compared to the measured PV module temperature at the single panels. The best results were achieved with the approach suggested by Skoplaki et al. [1]. Preliminary results indicate that for all PV technologies which were tested (monocrystalline, amorphous, microcrystalline and polycrystalline silicon and cadmium telluride), modelled and measured PV module temperatures show a higher agreement (RMSE about 3-4 K) compared to standard approaches in which wind is not considered. For further investigation the in-situ measured wind velocities were replaced with wind data from numerical weather forecast models (ECMWF, reanalysis fields). Our results show that the PV module temperature calculated with wind data from ECMWF is still in very good agreement with the measured one (R² > 0.9 for all technologies). Compared to the previous analysis, we find comparable mean values and an increasing standard deviation. These results open a promising approach for PV module

  8. Technological and economical analysis of salient pole and permanent magnet synchronous machines designed for wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Guendogdu, Tayfun, E-mail: tgundogdu@itu.edu.tr [Istanbul Technical University, Department of Electrical Engineering, Ayazaga Campus, 34469 Maslak/Istanbul (Turkey); Koemuergoez, Gueven, E-mail: komurgoz@itu.edu.tr [Istanbul Technical University, Department of Electrical Engineering, Ayazaga Campus, 34469 Maslak/Istanbul (Turkey)

    2012-08-15

    Chinese export restrictions already reduced the planning reliability for investments in permanent magnet wind turbines. Today the production of permanent magnets consumes the largest proportion of rare earth elements, with 40% of the rare earth-based magnets used for generators and other electrical machines. The cost and availability of NdFeB magnets will likely determine the production rate of permanent magnet generators. The high volatility of rare earth metals makes it very difficult to quote a price. Prices may also vary from supplier to supplier to an extent of up to 50% for the same size, shape and quantity with a minor difference in quality. The paper presents the analysis and the comparison of salient pole with field winding and of peripheral winding synchronous electrical machines, presenting important advantages. A neodymium alloy magnet rotor structure has been considered and compared to the salient rotor case. The Salient Pole Synchronous Machine and the Permanent Magnet Synchronous Machine were designed so that the plate values remain constant. The Eddy current effect on the windings is taken into account during the design, and the efficiency, output power and the air-gap flux density obtained after the simulation were compared. The analysis results clearly indicate that Salient Pole Synchronous Machine designs would be attractive to wind power companies. Furthermore, the importance of the design of electrical machines and the determination of criteria are emphasized. This paper will be a helpful resource in terms of examination and comparison of the basic structure and magnetic features of the Salient Pole Synchronous Machine and Permanent Magnet Synchronous Machine. Furthermore, an economic analysis of the designed machines was conducted. - Highlights: Black-Right-Pointing-Pointer Importance of the design of electrical machines and the determination of criteria are emphasized. Black-Right-Pointing-Pointer Machines were investigated in terms of

  9. ATLAS Data Preservation

    CERN Document Server

    Jones, Roger; The ATLAS collaboration

    2015-01-01

    Complementary to parallel open access and analysis preservation initiatives, ATLAS is taking steps to ensure that the data taken by the experiment during run-1 remain accessible and available for future analysis by the collaboration. An evaluation of what is required to achieve this is underway, examining the ATLAS data production chain to establish the effort required and potential problems. Several alternatives are explored, but the favoured solution is to bring the run 1 data and software in line with the equivalent to that which will be used for run 2. This will result in a coherent ATLAS dataset for the data already taken and that to come in the future.

  10. Women of ATLAS - International Women's Day 2016

    CERN Multimedia

    Biondi, Silvia

    2016-01-01

    Women play key roles in the ATLAS Experiment: from young physicists at the start of their careers to analysis group leaders and spokespersons of the collaboration. Celebrate International Women's Day by meeting a few of these inspiring ATLAS researchers.

  11. Large-scale, high-resolution wind resource mapping for wind farm planning and development in South Africa

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Badger, Jake; Hansen, Jens Carsten

    2014-01-01

    estimates are designed for national and provincial planning and strategic environmental impact assessment for wind power in South Africa and the results have therefore been made available in common GIS formats. The database of results is in the public domain and can be downloaded from the WASA web site......Numerical wind atlas data at 5 km resolution have been used to map the wind resources of the Wind Atlas for South Africa (WASA) domain in great detail: mean wind speed, mean wind power density, elevation and ruggedness index for every 250 metres over an area of 350,000 square kilometres. The wind......-climatological inputs to the wind resource mapping are wind atlas data sets derived from mesoscale modelling using the Karlsruhe Atmospheric Mesoscale Model (KAMM). The topographical inputs to the microscale modelling are 20-m digital height contours from 1:50,000 South African topographical maps and vector-format land...

  12. Large-scale, high-resolution wind resource mapping for wind farm planning and development in South Africa

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Badger, Jake; Hansen, Jens Carsten

    estimates are designed for national and provincial planning and strategic environmental impact assessment for wind power in South Africa and the results have therefore been made available in common GIS formats. The database of results is in the public domain and can be downloaded from the WASA web site......Numerical wind atlas data at 5 km resolution have been used to map the wind resources of the Wind Atlas for South Africa (WASA) domain in great detail: mean wind speed, mean wind power density, elevation and ruggedness index for every 250 metres over an area of 350,000 square kilometres. The wind......-climatological inputs to the wind resource mapping are wind atlas data sets derived from mesoscale modelling using the Karlsruhe Atmospheric Mesoscale Model (KAMM). The topographical inputs to the microscale modelling are 20-m digital height contours from 1:50,000 South African topographical maps and vector-format land...

  13. Variance Analysis of Wind and Natural Gas Generation under Different Market Structures: Some Observations

    Energy Technology Data Exchange (ETDEWEB)

    Bush, B.; Jenkin, T.; Lipowicz, D.; Arent, D. J.; Cooke, R.

    2012-01-01

    Does large scale penetration of renewable generation such as wind and solar power pose economic and operational burdens on the electricity system? A number of studies have pointed to the potential benefits of renewable generation as a hedge against the volatility and potential escalation of fossil fuel prices. Research also suggests that the lack of correlation of renewable energy costs with fossil fuel prices means that adding large amounts of wind or solar generation may also reduce the volatility of system-wide electricity costs. Such variance reduction of system costs may be of significant value to consumers due to risk aversion. The analysis in this report recognizes that the potential value of risk mitigation associated with wind generation and natural gas generation may depend on whether one considers the consumer's perspective or the investor's perspective and whether the market is regulated or deregulated. We analyze the risk and return trade-offs for wind and natural gas generation for deregulated markets based on hourly prices and load over a 10-year period using historical data in the PJM Interconnection (PJM) from 1999 to 2008. Similar analysis is then simulated and evaluated for regulated markets under certain assumptions.

  14. Global Sensitivity Analysis of High Speed Shaft Subsystem of a Wind Turbine Drive Train

    Directory of Open Access Journals (Sweden)

    Saeed Asadi

    2018-01-01

    Full Text Available The wind turbine dynamics are complex and critical area of study for the wind industry. Quantification of the effective factors to wind turbine performance is valuable for making improvements to both power performance and turbine health. In this paper, the global sensitivity analysis of validated mathematical model for high speed shaft drive train test rig has been developed in order to evaluate the contribution of systems input parameters to the specified objective functions. The drive train in this study consists of a 3-phase induction motor, flexible shafts, shafts’ coupling, bearing housing, and disk with an eccentric mass. The governing equations were derived by using the Lagrangian formalism and were solved numerically by Newmark method. The variance based global sensitivity indices are introduced to evaluate the contribution of input structural parameters correlated to the objective functions. The conclusion from the current research provides informative beneficial data in terms of design and optimization of a drive train setup and also can provide better understanding of wind turbine drive train system dynamics with respect to different structural parameters, ultimately designing more efficient drive trains. Finally, the proposed global sensitivity analysis (GSA methodology demonstrates the detectability of faults in different components.

  15. A 3-D aerodynamic method for the analysis of isolated horizontal-axis wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Ammara, I.; Masson, C.; Paraschivoiu, I. [Ecole Polytechnique, Montreal (Canada)

    1997-12-31

    In most existing performance-analysis methods, wind turbines are considered isolated so that interference effects caused by other rotors or by the site topography are neglected. The main objective of this paper is to propose a practical 3-D method suitable for the study of these effects, in order to optimize the arrangement and the positioning of Horizontal-Axis Wind Turbines (HAWTs) in a wind farm. In the proposed methodology, the flow field around isolated HAWTs is predicted by solving the 3-D, time-averaged, steady-state, incompressible, Navier-Stokes equations in which the turbines are represented by distributions of momentum sources. The resulting governing equations are solved using a Control-Volume Finite Element Method (CVFEM). The fundamental aspects related to the development of a practical 3-D method are discussed in this paper, with an emphasis on some of the challenges that arose during its implementation. The current implementation is limited to the analysis of isolated HAWTs. Preliminary results have indicated that, the proposed 3-D method reaches the same level of accuracy, in terms of performance predictions, that the previously developed 2-D axisymmetric model and the well-known momentum-strip theory, while still using reasonable computers resources. It can be considered as a useful tool for the design of HAWTs. Its main advantages, however, are its intrinsic capacity to predict the details of the flow in the wake, and its capabilities of modelling arbitrary wind-turbine arrangements and including ground effects.

  16. Dynamic analysis of a 5-MW tripod offshore wind turbine by considering fluid-structure interaction

    Science.gov (United States)

    Zhang, Li-wei; Li, Xin

    2017-10-01

    Fixed offshore wind turbines usually have large underwater supporting structures. The fluid influences the dynamic characteristics of the structure system. The dynamic model of a 5-MW tripod offshore wind turbine considering the pile-soil system and fluid structure interaction (FSI) is established, and the structural modes in air and in water are obtained by use of ANSYS. By comparing low-order natural frequencies and mode shapes, the influence of sea water on the free vibration characteristics of offshore wind turbine is analyzed. On basis of the above work, seismic responses under excitation by El-Centro waves are calculated by the time-history analysis method. The results reveal that the dynamic responses such as the lateral displacement of the foundation and the section bending moment of the tubular piles increase substantially under the influence of the added-mass and hydrodynamic pressure of sea water. The method and conclusions presented in this paper can provide a theoretical reference for structure design and analysis of offshore wind turbines fixed in deep seawater.

  17. Wind Turbine Performance Measurements by Means of Dynamic Data Analysis

    DEFF Research Database (Denmark)

    Friis Pedersen, Troels; Wagner, Rozenn; Demurtas, Giorgio

    tools have been developed by authors to try to make the drift field and fixed point determination more robust. A sensitivity analysis with nacelle lidar data showed drift determination was not very dependent on the time steps applied, leading to use of time steps of 2-3 points for each dataset. Power...... bin size should be fixed. Data averaging with 5 sec data was more distinct for determination of the fixed points than 2 and 1 sec data. With the nacelle lidar the Langevin method seemed to produce a power curve that was comparable to the IEC power curve. Analysis of the Langevin method with spinner...

  18. Draft South African wind energy technology platform: preliminary wind energy research and development framework

    CSIR Research Space (South Africa)

    Szewczuk, S

    2011-08-01

    Full Text Available The South African Wind Energy Technology Programme (SAWEP) Phase 1 aims to achieve two key strategic outputs that will guide South Africa on wind energy development. One of these outputs is the Wind Atlas for South Africa (WASA) which will play a...

  19. Technological and economical analysis of salient pole and permanent magnet synchronous machines designed for wind turbines

    Science.gov (United States)

    Gündoğdu, Tayfun; Kömürgöz, Güven

    2012-08-01

    Chinese export restrictions already reduced the planning reliability for investments in permanent magnet wind turbines. Today the production of permanent magnets consumes the largest proportion of rare earth elements, with 40% of the rare earth-based magnets used for generators and other electrical machines. The cost and availability of NdFeB magnets will likely determine the production rate of permanent magnet generators. The high volatility of rare earth metals makes it very difficult to quote a price. Prices may also vary from supplier to supplier to an extent of up to 50% for the same size, shape and quantity with a minor difference in quality. The paper presents the analysis and the comparison of salient pole with field winding and of peripheral winding synchronous electrical machines, presenting important advantages. A neodymium alloy magnet rotor structure has been considered and compared to the salient rotor case. The Salient Pole Synchronous Machine and the Permanent Magnet Synchronous Machine were designed so that the plate values remain constant. The Eddy current effect on the windings is taken into account during the design, and the efficiency, output power and the air-gap flux density obtained after the simulation were compared. The analysis results clearly indicate that Salient Pole Synchronous Machine designs would be attractive to wind power companies. Furthermore, the importance of the design of electrical machines and the determination of criteria are emphasized. This paper will be a helpful resource in terms of examination and comparison of the basic structure and magnetic features of the Salient Pole Synchronous Machine and Permanent Magnet Synchronous Machine. Furthermore, an economic analysis of the designed machines was conducted.

  20. SMART Wind Turbine Rotor: Data Analysis and Conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Jonathan C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Barone, Matthew F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yoder, Nathanael C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-01-29

    This report documents the data post-processing and analysis performed to date on the field test data. Results include the control capability of the trailing edge flaps, the combined structural and aerodynamic damping observed through application of step actuation with ensemble averaging, direct observation of time delays associated with aerodynamic response, and techniques for characterizing an operating turbine with active rotor control.