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Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

SERI advanced wind turbine blades  

DOE Green Energy (OSTI)

The primary goal of the Solar Energy Research Institute`s (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

Tangler, J.; Smith, B.; Jager, D.

1992-02-01T23:59:59.000Z

2

SERI advanced wind turbine blades  

DOE Green Energy (OSTI)

The primary goal of the Solar Energy Research Institute's (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

Tangler, J.; Smith, B.; Jager, D.

1992-02-01T23:59:59.000Z

3

Structural Health Monitoring of Wind Turbine Blades  

Science Conference Proceedings (OSTI)

Presentation Title, Structural Health Monitoring of Wind Turbine Blades. Author(s) ... is mandatory for the cost-effective operation of an offshore wind power plant.

4

Wind Turbine Blade Structural Health Monitoring  

Science Conference Proceedings (OSTI)

Structural health monitoring (SHM) is the automated inspection and evaluation of structures such as wind turbine blades. This report examines the current state-of-the-art blade SHM systems, identifies future trends, and outlines a methodology for probabilistic cost-benefit analysis of the application of SHM systems to wind turbine blades. The reliability of wind turbine blades is an ongoing concern for the wind industry. Applying SHM to blades may be one way to reduce blade failure rates and reduce the d...

2010-12-31T23:59:59.000Z

5

Applications: Wind turbine and blade design  

E-Print Network (OSTI)

Capability Applications: Wind turbine and blade design optimization Energy production enhancement Summary: As the wind energy industry works to provide the infra- structure necessary for wind turbine develops a means to aug- ment power production with wind-derived energy. Turbines have become massive

6

Wooden wind turbine blade manufacturing process  

DOE Patents (OSTI)

A wooden wind turbine blade is formed by laminating wood veneer in a compression mold having the exact curvature needed for one side of the blade, following which the other side of the blade is ground flat along its length but twisted with respect to the blade axis.

Coleman, Clint (Warren, VT)

1986-01-01T23:59:59.000Z

7

Load attenuating passively adaptive wind turbine blade  

DOE Patents (OSTI)

A method and apparatus for improving wind turbine performance by alleviating loads and controlling the rotor. The invention employs the use of a passively adaptive blade that senses the wind velocity or rotational speed, and accordingly modifies its aerodynamic configuration. The invention exploits the load mitigation prospects of a blade that twists toward feather as it bends. The invention includes passively adaptive wind turbine rotors or blades with currently preferred power control features. The apparatus is a composite fiber horizontal axis wind-turbine blade, in which a substantial majority of fibers in the blade skin are inclined at angles of between 15 and 30 degrees to the axis of the blade, to produces passive adaptive aeroelastic tailoring (bend-twist coupling) to alleviate loading without unduly jeopardizing performance.

Veers, Paul S. (Albuquerque, NM); Lobitz, Donald W. (Albuquerque, NM)

2003-01-01T23:59:59.000Z

8

TECHNICALADVANCES IN EPOXY TECHNOLOGY FOR WIND TURBINE BLADE COMPOSITE FABRICATION  

E-Print Network (OSTI)

TECHNICALADVANCES IN EPOXY TECHNOLOGY FOR WIND TURBINE BLADE COMPOSITE FABRICATION George C. Jacob reliability in many demanding applications including components for aerospace and wind turbine blades. While in operation, wind turbine blades are subjected to significant stresses from their movement, wind and other

9

Methods of making wind turbine rotor blades  

DOE Patents (OSTI)

A method of manufacturing a root portion of a wind turbine blade includes, in an exemplary embodiment, providing an outer layer of reinforcing fibers including at least two woven mats of reinforcing fibers, providing an inner layer of reinforcing fibers including at least two woven mats of reinforcing fibers, and positioning at least two bands of reinforcing fibers between the inner and outer layers, with each band of reinforcing fibers including at least two woven mats of reinforcing fibers. The method further includes positioning a mat of randomly arranged reinforcing fibers between each pair of adjacent bands of reinforcing fibers, introducing a polymeric resin into the root potion of the wind turbine blade, infusing the resin through the outer layer, the inner layer, each band of reinforcing fibers, and each mat of random reinforcing fibers, and curing the resin to form the root portion of the wind turbine blade.

Livingston, Jamie T. (Pensacola, FL); Burke, Arthur H. E. (Gulf Breeze, FL); Bakhuis, Jan Willem (Nijverdal, NL); Van Breugel, Sjef (Enschede, NL); Billen, Andrew (Daarlerveen, NL)

2008-04-01T23:59:59.000Z

10

EFFECTS OF FIBER WAVINESS ON COMPOSITES FOR WIND TURBINE BLADES  

E-Print Network (OSTI)

EFFECTS OF FIBER WAVINESS ON COMPOSITES FOR WIND TURBINE BLADES J.F. Mandell D.D. Samborsky and L Composite materials of interest for wind turbine blades use relatively low cost fibers, resins and processes WORDS: Composite Materials, Fiber Waviness, Compressive Strength #12;1. INTRODUCTION Wind turbine blades

11

Cost Study for Large Wind Turbine Blades  

SciTech Connect

The cost study for large wind turbine blades reviewed three blades of 30 meters, 50 meters, and 70 meters in length. Blade extreme wind design loads were estimated in accordance with IEC Class I recommendations. Structural analyses of three blade sizes were performed at representative spanwise stations assuming a stressed shell design approach and E-glass/vinylester laminate. A bill of materials was prepared for each of the three blade sizes using the laminate requirements prepared during the structural analysis effort. The labor requirements were prepared for twelve major manufacturing tasks. TPI Composites developed a conceptual design of the manufacturing facility for each of the three blade sizes, which was used for determining the cost of labor and overhead (capital equipment and facilities). Each of the three potential manufacturing facilities was sized to provide a constant annual rated power production (MW per year) of the blades it produced. The cost of the production tooling and overland transportation was also estimated. The results indicate that as blades get larger, materials become a greater proportion of total cost, while the percentage of labor cost is decreased. Transportation costs decreased as a percentage of total cost. The study also suggests that blade cost reduction efforts should focus on reducing material cost and lowering manufacturing labor, because cost reductions in those areas will have the strongest impact on overall blade cost.

ASHWILL, THOMAS D.

2003-05-01T23:59:59.000Z

12

Dynamic stall on wind turbine blades  

DOE Green Energy (OSTI)

Dynamic loads must be predicted accurately in order to estimate the fatigue life of wind turbines operating in turbulent environments. Dynamic stall contributes to increased dynamic loads during normal operation of all types of horizontal-axis wind turbine (HAWTs). This report illustrates how dynamic stall varies throughout the blade span of a 10 m HAWT during yawed and unyawed operating conditions. Lift, drag, and pitching moment coefficients during dynamics stall are discussed. Resulting dynamic loads are presented, and the effects of dynamic stall on yaw loads are demonstrated using a yaw loads dynamic analysis (YAWDYN). 12 refs., 22 figs., 1 tab.

Butterfield, C.P.; Simms, D.; Scott, G. [National Renewable Energy Lab., Golden, CO (United States)] [National Renewable Energy Lab., Golden, CO (United States); Hansen, A.C. [Utah Univ., Salt Lake City, UT (United States)] [Utah Univ., Salt Lake City, UT (United States)

1991-12-01T23:59:59.000Z

13

Sinomatech Wind Power Blade aka Sinoma Science Technology Wind Turbine  

Open Energy Info (EERE)

Sinomatech Wind Power Blade aka Sinoma Science Technology Wind Turbine Sinomatech Wind Power Blade aka Sinoma Science Technology Wind Turbine Blade Co Ltd Jump to: navigation, search Name Sinomatech Wind Power Blade (aka Sinoma Science & Technology Wind Turbine Blade Co Ltd) Place Nanjing, Jiangsu Province, China Zip 210012 Sector Wind energy Product Jiangsu-based wind turbine blade manufactuer. Coordinates 32.0485°, 118.778969° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":32.0485,"lon":118.778969,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

14

First wind turbine blade delivered to Pantex | National Nuclear...  

National Nuclear Security Administration (NNSA)

Work crews began to erect the first of five wind turbines that will make up the Pantex Renewable Energy Project (PREP). The first wind turbine blade was delivered to the site...

15

Vertical axis wind turbine with continuous blade angle adjustment  

E-Print Network (OSTI)

The author presents a concept for a vertical axis wind turbine that utilizes each blade's entire rotational cycle for power generation. Each blade has its own vertical axis of rotation and is constrained to rotate at the ...

Weiss, Samuel Bruce

2010-01-01T23:59:59.000Z

16

Method of making a wooden wind turbine blade  

DOE Patents (OSTI)

A wooden wind turbine blade is formed by laminating wood veneer in a compression mold having the exact curvature needed for one side of the blade, following which the other side of the blade is ground flat along its length but twisted with respect to the blade axis.

Coleman, Clint (Warren, VT)

1984-01-01T23:59:59.000Z

17

Method of making a wooden wind turbine blade  

DOE Patents (OSTI)

A wooden wind turbine blade is formed by laminating wood veneer in a compression mold having the exact curvature needed for one side of the blade, following which the other side of the blade is ground flat along its length but twisted with respect to the blade axis. 8 figs.

Coleman, C.

1984-08-14T23:59:59.000Z

18

NREL: Wind Research - Fabric-Covered Blades Could Make Wind Turbines...  

NLE Websites -- All DOE Office Websites (Extended Search)

Fabric-Covered Blades Could Make Wind Turbines Cheaper and More Efficient A photo of a crew of workers watching as a wind blade is hauled up to a turbine for assembly. A new...

19

An evolutionary environment for wind turbine blade design  

Science Conference Proceedings (OSTI)

The aerodynamic design of wind turbine blades is carried out by means of evolutionary techniques within an automatic design environment based on evolution. A simple, fast, and robust aerodynamic simulator is embedded in the design environment to predict ...

V. Daz Cass; F. Lopez Pea; A. Lamas; R. J. Duro

2005-06-01T23:59:59.000Z

20

Reaction Injection Molded 7.5 Meter Wind Turbine Blade  

DOE Green Energy (OSTI)

An optimized small turbine blade (7.5m radius) was designed and a partial section molded with the RIM (reaction-injection molded polymer) process for mass production. The intended market is for generic three-bladed wind turbines, 100 kilowatts or less, for grid-assist end users with rural and semi-rural sites, such as the farm/ranch market, having low to moderate IEC Class 3-4 wind regimes. This blade will have substantial performance improvements over, and be cheaper than, present-day 7.5m blades. This is made possible by the injection-molding process, which yields high repeatability, accurate geometry and weights, and low cost in production quantities. No wind turbine blade in the 7.5m or greater size has used this process. The blade design chosen uses a RIM skin bonded to a braided infused carbon fiber/epoxy spar. This approach is attractive to present users of wind turbine blades in the 5-10m sizes. These include rebladeing California wind farms, refurbishing used turbines for the Midwest farm market, and other manufacturers introducing new turbines in this size range.

David M. Wright; DOE Project Officer - Keith Bennett

2007-07-31T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Dynamically Adjustable Wind Turbine Blades: Adaptive Turbine Blades, Blown Wing Technology for Low-Cost Wind Power  

SciTech Connect

Broad Funding Opportunity Announcement Project: Caitin is developing wind turbines with a control system that delivers compressed air from special slots located in the surface of its blades. The compressed air dynamically adjusts the aerodynamic performance of the blades, and can essentially be used to control lift, drag, and ultimately power. This control system has been shown to exhibit high levels of control in combination with an exceptionally fast response rate. The deployment of such a control system in modern wind turbines would lead to better management of the load on the system during peak usage, allowing larger blades to be deployed with a resulting increase in energy production.

2010-02-02T23:59:59.000Z

22

Innovative Design Approaches for Large Wind Turbine Blades  

SciTech Connect

The primary goal of the WindPACT Blade System Design Study (BSDS) was investigation and evaluation of design and manufacturing issues for wind turbine blades in the one to ten megawatt size range. The initial project task was to assess the fundamental physical and manufacturing issues that govern and constrain large blades and entails three basic elements: (1) a parametric scaling study to assess blade structure using current technology, (2) an economic study of the cost to manufacture, transport, and install large blades, and (3) identification of promising innovative design approaches that show potential for overcoming fundamental physical and manufacturing constraints. This report discusses several innovative design approaches and their potential for blade cost reduction. During this effort we reviewed methods for optimizing the blade cross-section to improve structural and manufacturing characteristics. We also analyzed and compared a number of composite materials and evaluated their relative merits for use in large wind turbine blades in the range from 30 meters to 70 meters. The results have been summarized in dimensional and non-dimensional format to aid in interpretation. These results build upon earlier parametric and blade cost studies, which were used as a guide for the innovative design approaches explored here.

ASHWILL, THOMAS D.

2003-03-01T23:59:59.000Z

23

Aerodynamic testing of a rotating wind turbine blade  

DOE Green Energy (OSTI)

Aerodynamic, load, flow-visualization, and inflow measurements were taken on a downwind horizontal-axis wind turbine (HAWT). A video camera mounted on the rotor recorded video images of tufts attached to the low-pressure side of the blade. Strain gages, mounted every 10% of the blade's span, provided load and pressure measurements. Pressure taps at 32 chordwise positions recorded pressure distributions. Wind inflow was measured via a vertical-plane array of anemometers located 10 m upwind. The objectives of the test were to address whether airfoil pressure distributions measured on a rotating blade differed from those measured in the wind tunnel, if radial flow near or in the boundary layer of the airfoil affected pressure distributions, if dynamic stall could result in increased dynamic loads, and if the location of the separation boundary measured on the rotating blade agreed with that measured in two-dimensional flow in the wind tunnel. 6 refs., 9 figs., 1 tab.

Butterfield, C.P.; Nelsen, E.N.

1990-01-01T23:59:59.000Z

24

The use of carbon fibers in wind turbine blade design: A SERI-8 blade example  

DOE Green Energy (OSTI)

The benefit of introducing carbon fibers in a wind turbine blade was evaluated. The SERI-8 wind turbine blade was used as a baseline for study. A model of the blade strength and stiffness properties was created using the 3D-Beam code; the predicted geometry and structural properties were validated against available data and static test results. Different enhanced models, which represent different volumes of carbon fibers in the blade, were also studied for two design options: with and without bend-twist coupling. Studies indicate that hybrid blades have excellent structural properties compared to the all-glass SERI-8 blade. Recurring fabrication costs were also included in the study. The cost study highlights the importance of the labor-cost to material-cost ratio in the cost benefits and penalties of fabrication of a hybrid glass and carbon blade.

ONG,CHENG-HUAT; TSAI,STEPHEN W.

2000-03-01T23:59:59.000Z

25

Innovative design approaches for large wind turbine blades : final report.  

SciTech Connect

The goal of the Blade System Design Study (BSDS) was investigation and evaluation of design and manufacturing issues for wind turbine blades in the one to ten megawatt size range. A series of analysis tasks were completed in support of the design effort. We began with a parametric scaling study to assess blade structure using current technology. This was followed by an economic study of the cost to manufacture, transport and install large blades. Subsequently we identified several innovative design approaches that showed potential for overcoming fundamental physical and manufacturing constraints. The final stage of the project was used to develop several preliminary 50m blade designs. The key design impacts identified in this study are: (1) blade cross-sections, (2) alternative materials, (3) IEC design class, and (4) root attachment. The results show that thick blade cross-sections can provide a large reduction in blade weight, while maintaining high aerodynamic performance. Increasing blade thickness for inboard sections is a key method for improving structural efficiency and reducing blade weight. Carbon/glass hybrid blades were found to provide good improvements in blade weight, stiffness, and deflection when used in the main structural elements of the blade. The addition of carbon resulted in modest cost increases and provided significant benefits, particularly with respect to deflection. The change in design loads between IEC classes is quite significant. Optimized blades should be designed for each IEC design class. A significant portion of blade weight is related to the root buildup and metal hardware for typical root attachment designs. The results show that increasing the number of blade fasteners has a positive effect on total weight, because it reduces the required root laminate thickness.

2004-05-01T23:59:59.000Z

26

User's Guide to MBC3: Multi-Blade Coordinate Transformation Code for 3-Bladed Wind Turbine  

DOE Green Energy (OSTI)

This guide explains how to use MBC3, a MATLAB-based script NREL developed to perform multi-blade coordinate transformation of system matrices for three-bladed wind turbines. In its current form, MBC3 can be applied to system matrices generated by FAST.2.

Bir, G. S.

2010-09-01T23:59:59.000Z

27

An evaluation of wind turbine blade cross section analysis techniques.  

SciTech Connect

The blades of a modern wind turbine are critical components central to capturing and transmitting most of the load experienced by the system. They are complex structural items composed of many layers of fiber and resin composite material and typically, one or more shear webs. Large turbine blades being developed today are beyond the point of effective trial-and-error design of the past and design for reliability is always extremely important. Section analysis tools are used to reduce the three-dimensional continuum blade structure to a simpler beam representation for use in system response calculations to support full system design and certification. One model simplification approach is to analyze the two-dimensional blade cross sections to determine the properties for the beam. Another technique is to determine beam properties using static deflections of a full three-dimensional finite element model of a blade. This paper provides insight into discrepancies observed in outputs from each approach. Simple two-dimensional geometries and three-dimensional blade models are analyzed in this investigation. Finally, a subset of computational and experimental section properties for a full turbine blade are compared.

Paquette, Joshua A.; Griffith, Daniel Todd; Laird, Daniel L.; Resor, Brian Ray

2010-03-01T23:59:59.000Z

28

WIND TURBINE BLADE DESIGN BASED ON DURABILITY AND DAMAGE TOLERANCE  

DOE Green Energy (OSTI)

The objective of the program was to demonstrate and verify Certification-by-Analysis (CBA) capability for wind turbine blades made from advanced lightweight composite materials. The approach integrated durability and damage tolerance analysis with robust design and virtual testing capabilities to deliver superior, durable, low weight, low cost, long life, and reliable wind blade design. The GENOA durability and life prediction software suite was be used as the primary simulation tool. First, a micromechanics-based computational approach was used to assess the durability of composite laminates with ply drop features commonly used in wind turbine applications. Ply drops occur in composite joints and closures of wind turbine blades to reduce skin thicknesses along the blade span. They increase localized stress concentration, which may cause premature delamination failure in composite and reduced fatigue service life. Durability and damage tolerance (D&DT) were evaluated utilizing a multi-scale micro-macro progressive failure analysis (PFA) technique. PFA is finite element based and is capable of detecting all stages of material damage including initiation and propagation of delamination. It assesses multiple failure criteria and includes the effects of manufacturing anomalies (i.e., void, fiber waviness). Two different approaches have been used within PFA. The first approach is Virtual Crack Closure Technique (VCCT) PFA while the second one is strength-based. Constituent stiffness and strength properties for glass and carbon based material systems were reverse engineered for use in D&DT evaluation of coupons with ply drops under static loading. Lamina and laminate properties calculated using manufacturing and composite architecture details matched closely published test data. Similarly, resin properties were determined for fatigue life calculation. The simulation not only reproduced static strength and fatigue life as observed in the test, it also showed composite damage and fracture modes that resemble those reported in the tests. The results show that computational simulation can be relied on to enhance the design of tapered composite structures such as the ones used in turbine wind blades. A computational simulation for durability, damage tolerance (D&DT) and reliability of composite wind turbine blade structures in presence of uncertainties in material properties was performed. A composite turbine blade was first assessed with finite element based multi-scale progressive failure analysis to determine failure modes and locations as well as the fracture load. D&DT analyses were then validated with static test performed at Sandia National Laboratories. The work was followed by detailed weight analysis to identify contribution of various materials to the overall weight of the blade. The methodology ensured that certain types of failure modes, such as delamination progression, are contained to reduce risk to the structure. Probabilistic analysis indicated that composite shear strength has a great influence on the blade ultimate load under static loading. Weight was reduced by 12% with robust design without loss in reliability or D&DT. Structural benefits obtained with the use of enhanced matrix properties through nanoparticles infusion were also assessed. Thin unidirectional fiberglass layers enriched with silica nanoparticles were applied to the outer surfaces of a wind blade to improve its overall structural performance and durability. The wind blade was a 9-meter prototype structure manufactured and tested subject to three saddle static loading at Sandia National Laboratory (SNL). The blade manufacturing did not include the use of any nano-material. With silica nanoparticles in glass composite applied to the exterior surfaces of the blade, the durability and damage tolerance (D&DT) results from multi-scale PFA showed an increase in ultimate load of the blade by 9.2% as compared to baseline structural performance (without nano). The use of nanoparticles lead to a delay in the onset of delamination. Load-displacement relati

Galib Abumeri; Frank Abdi (PhD)

2012-02-16T23:59:59.000Z

29

Estimation of Blade and Tower Properties for the Gearbox Research Collaborative Wind Turbine  

SciTech Connect

This report documents the structural and modal properties of the blade and tower of a 3-bladed 750-kW upwind turbine to develop an aeroelastic model of the wind turbine.

Bir, G.S.; Oyague, F.

2007-11-01T23:59:59.000Z

30

Spanwise aerodynamic loads on a rotating wind turbine blade  

DOE Green Energy (OSTI)

Wind turbine performance and load predictions depend on accurate airfoil performance data. Wind tunnel test data are typically used which accurately describe two-dimensional airfoil performance characteristics. Usually these data are only available for a range of angles of attack from 0 to 15 deg, which excludes the stall characteristics. Airfoils on stall-controlled wind turbines operate in deep stall in medium to high winds. Therefore it is very important to know how the airfoil will perform in these high load conditions. Butterfield et al. have shown that three-dimensional effects and rotation of the blade modify the two-dimensional performance of the airfoil. These effects are modified to different degrees throughout the blade span. The Solar Energy Research Institute (SERI) has conducted a series of tests to measure the spanwise variation of airfoil performance characteristics on a rotating wind turbine blade. Maximum lift coefficients were measured to be 200% greater than wind tunnel results at the 30% span. Stall characteristics were generally modified throughout the span. Lift characteristics were unmodified for low to medium angles of attack. This paper discusses these test results for four spanwise locations. 8 refs., 12 figs.

Butterfield, C.P.; Simms, D.; Musial, W.; Scott, G.

1990-10-01T23:59:59.000Z

31

Multi-piece wind turbine rotor blades and wind turbines incorporating same  

DOE Patents (OSTI)

A multisection blade for a wind turbine includes a hub extender having a pitch bearing at one end, a skirt or fairing having a hole therethrough and configured to mount over the hub extender, and an outboard section configured to couple to the pitch bearing.

Moroz; Emilian Mieczyslaw (San Diego, CA)

2008-06-03T23:59:59.000Z

32

Energy harvesting to power sensing hardware onboard wind turbine blade  

SciTech Connect

Wind turbines are becoming a larger source of renewable energy in the United States. However, most of the designs are geared toward the weather conditions seen in Europe. Also, in the United States, manufacturers have been increasing the length of the turbine blades, often made of composite materials, to maximize power output. As a result of the more severe loading conditions in the United States and the material level flaws in composite structures, blade failure has been a more common occurrence in the U.S. than in Europe. Therefore, it is imperative that a structural health monitoring system be incorporated into the design of the wind turbines in order to monitor flaws before they lead to a catastrophic failure. Due to the rotation of the turbine and issues related to lightning strikes, the best way to implement a structural health monitoring system would be to use a network of wireless sensor nodes. In order to provide power to these sensor nodes, piezoelectric, thermoelectric and photovoltaic energy harvesting techniques are examined on a cross section of a CX-100 wind turbine blade in order to determine the feasibility of powering individual nodes that would compose the sensor network.

Carlson, Clinton P [Los Alamos National Laboratory; Schichting, Alexander D [Los Alamos National Laboratory; Quellette, Scott [Los Alamos National Laboratory; Faringolt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

33

Wooden wind turbine blade manufacturing process  

SciTech Connect

A laminated wooden rotor blade is described having a flatbottomed air foil, comprising a two-sided tapered laminate composed of compression bonded parallel layers of wood having a convex side in a predetermined contour to which all of the layers of wood are approximately parallel over the entire length of the blade and a flat twisted side, the surface of which at any point along the length of the blade is rectilinear in cross section but of varying orientation along the length of the blade according to a predetermined twist schedule, the flat side cutting across the laminae of the blade to reveal the parallel edges thereof.

Coleman, C.

1986-07-01T23:59:59.000Z

34

A simple method of estimating wind turbine blade fatigue at potential wind turbine sites  

SciTech Connect

This paper presents a technique of estimating blade fatigue damage at potential wind turbine sites. The cornerstone of this technique is a simple model for the blade`s root flap bending moment. The model requires as input a simple set of wind measurements which may be obtained as part of a routine site characterization study. By using the model to simulate a time series of the root flap bending moment, fatigue damage rates may be estimated. The technique is evaluated by comparing these estimates with damage estimates derived from actual bending moment data; the agreement between the two is quite good. The simple connection between wind measurements and fatigue provided by the model now allows one to readily discriminate between damaging and more benign wind environments.

Barnard, J.C.; Wendell, L.L.

1995-06-01T23:59:59.000Z

35

Aeroelastic tailoring in wind-turbine blade applications  

DOE Green Energy (OSTI)

This paper reviews issues related to the use of aeroelastic tailoring as a cost-effective, passive means to shape the power curve and reduce loads. Wind turbine blades bend and twist during operation, effectively altering the angle of attack, which in turn affects loads and energy production. There are blades now in use that have significant aeroelastic couplings, either on purpose or because of flexible and light-weight designs. Since aeroelastic effects are almost unavoidable in flexible blade designs, it may be desirable to tailor these effects to the authors advantage. Efforts have been directed at adding flexible devices to a blade, or blade tip, to passively regulate power (or speed) in high winds. It is also possible to build a small amount of desirable twisting into the load response of a blade with proper asymmetric fiber lay up in the blade skin. (Such coupling is akin to distributed {delta}{sub 3} without mechanical hinges.) The tailored twisting can create an aeroelastic effect that has payoff in either better power production or in vibration alleviation, or both. Several research efforts have addressed different parts of this issue. Research and development in the use of aeroelastic tailoring on helicopter rotors is reviewed. Potential energy gains as a function of twist coupling are reviewed. The effects of such coupling on rotor stability have been studied and are presented here. The ability to design in twist coupling with either stretching or bending loads is examined also.

Veers, P.; Lobitz, D. [Sandia National Labs., Albuquerque, NM (United States); Bir, G. [National Renewable Energy Lab., Golden, CO (United States). National Wind Technology Center

1998-04-01T23:59:59.000Z

36

Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects  

E-Print Network (OSTI)

1 Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects Jared W. Nelson The Blade Reliability Collaborative has been formed to perform comprehensive studies to improve wind turbine uni-directional wind turbine fiber-reinforced composite material with an epoxy resin were utilized

37

Vibration and Structural Response of Hybrid Wind Turbine Blades  

E-Print Network (OSTI)

Renewable energy is a serious alternative to deliver the energy needs of an increasing world population and improve economic activity. Wind energy provides better environmental and economic benefits in comparison with the other renewable energy sources. Wind energy is capable of providing 72 TW (TW = 10^12 W) of electric power, which is approximately four and half times the world energy consumption of 15.8 TW as reported in 2006. Since power output extracted from wind turbines is proportional to the square of the blade length and the cube of the wind speed, wind turbine size has grown rapidly in the last two decades to match the increase in power output. As the blade length increases, so does its weight opening up design possibilities to introduce hybrid glass and carbon fiber composite materials as lightweight structural load bearing alternatives. Herein, we investigate the feasibility of introducing modular composite tubulars as well as hybrid sandwich composite skins in the next generation blades. After selecting a target energy output, 8 MW with 80 m blade, airfoil geometry and the layup for the skin as well as internal reinforcements are proposed. They are incorporated into the computational blade via linear shell elements for the skin, and linear beam elements for the composite tubulars to assess the relationship between weight reduction and structural performance. Computational simulations are undertaken to understand the static and dynamic regimes; specifically, displacements, stresses, and vibration modes. The results showed that the composite layers did not exhibit any damage. However, in the balsa core of the sandwich skin, the von Mises stress exceeded its allowable at wind speeds ranging from 11.0 m/sec to 12.6 m/sec. In the blades with composite tubular reinforcement, two different types of damage are observed: a. Stress concentrations at the tubular-skin attachments, and b. Highest von Mises stress caused by the flapping bending moment. The vibration studies revealed a strong coupling mode, bending and twist, at the higher natural frequencies of the blade with tubular truss configuration. The weight saving measures in developing lighter blades in this study did not detract from the blades structural response for the selected load cases.

Nanami, Norimichi

2010-12-01T23:59:59.000Z

38

NREL: Technology Transfer - Fabric-Covered Blades Could Make Wind Turbines  

NLE Websites -- All DOE Office Websites (Extended Search)

Fabric-Covered Blades Could Make Wind Turbines Cheaper and More Efficient Fabric-Covered Blades Could Make Wind Turbines Cheaper and More Efficient A photo of a crew of workers watching as a wind blade is hauled up to a turbine for assembly. A new fabric-wrapped wind blade could eventually replace the traditional fiberglass blade, providing for lighter turbine components that could be built and assembled on site. January 2, 2013 A new design that calls for wrapping architectural fabric around metal wind turbine blades-instead of the traditional fiberglass-could be the latest revolution in dramatically reducing the cost of wind-produced power. That's the focus of a new project that partners NREL with General Electric (GE) and Virginia Polytechnic Institute & State University. Together, they are rethinking the way wind blades are designed,

39

Preform spar cap for a wind turbine rotor blade  

DOE Patents (OSTI)

A spar cap for a wind turbine rotor blade. The spar cap may include multiple preform components. The multiple preform components may be planar sheets having a swept shape with a first end and a second end. The multiple preform components may be joined by mating the first end of a first preform component to the second end of a next preform component, forming the spar cap.

Livingston, Jamie T. (Simpsonville, SC); Driver, Howard D. (Greer, SC); van Breugel, Sjef (Enschede, NL); Jenkins, Thomas B. (Cantonment, FL); Bakhuis, Jan Willem (Nijverdal, NL); Billen, Andrew J. (Daarlerveen, NL); Riahi, Amir (Pensacola, FL)

2011-07-12T23:59:59.000Z

40

FATIGUE RESISTANT FIBERGLASS LAMINATES FOR WIND TURBINE BLADES (published for Wind Energy 1996, ASME, pp. 46-51)  

E-Print Network (OSTI)

FATIGUE RESISTANT FIBERGLASS LAMINATES FOR WIND TURBINE BLADES (published for Wind Energy 1996/MSU database to lifetime prediction as described in Ref. [1]. INTRODUCTION Most U.S. fiberglass wind turbine Turbine Blade Lifetime Predictions" Proc. 1996 ASME Wind Energy Symposium. (To be published) 2. J

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Test evaluation of a laminated wood wind turbine blade concept  

SciTech Connect

Because of the high stiffness and fatigue strength of wood (as compared to density) along with the low cost manufacturing techniques available, a laminated wood wind turbine blade application has been studied. This report presents the results of the testing performed on elements of the wood blade-to-hub transition section which uses steel studs cast into a laminated wood spar with a filled epoxy. Individual stud samples were tested for both ultimate load carrying capability and fatigue strength. A one-time pull-out load of 78,000 lb was achieved for a 15 in. long stud with a diameter of 1 in. Tension-tension fatigue indicated that peak loads on the order of 40% of ultimate could be maintained as an endurance limit (mean load = 20,000 lb, cyclic load = +-15,000 lb). Following the individual stud testing, a full-scale inboard blade section (20 ft in length) was tested.

Faddoul, J.R.

1981-05-01T23:59:59.000Z

42

Application of BSTRAIN software for wind turbine blade testing  

DOE Green Energy (OSTI)

NREL currently operates the largest structural testing facility in US for testing wind turbine blades. A data acquisition system was developed to measure blade response and monitor test status; it is called BSTRAIN (Blade Structural Test Real-time Acquisition Interface Network). Software objectives were to develop a robust, easy-to-use computer program that could automatically collect data from static and fatigue blade tests without missing any significant events or overloading the computer with excess data. The program currently accepts inputs from up to 32 channels but can be expanded to over 1000 channels. In order to reduce the large amount of data collected during long fatigue tests, options for real-time data processing were developed including peak-valley series collection, peak-valley decimation, block decimation, and continuous recording of all data. Other BSTRAIN features include automated blade stiffness checks, remote terminal access to blade test status, and automated VCR control for continuous test recording. Results from tests conducted with the software revealed areas for improvement including test accuracy, post-processing analysis, and further data reduction.

Musial, W D; Clark, M E [National Renewable Energy Lab., Golden, CO (United States); Stensland, T [Stensland (T.), Lakewood, CO (United States)

1996-07-01T23:59:59.000Z

43

Blade Offset and Pitch Effects on a High Solidity Vertical Axis Wind Turbine  

E-Print Network (OSTI)

ABSTRACT A high solidity, small scale, 2.5m diameter by 3m high Vertical Axis Wind Turbine (VAWT, performance 1. INTRODUCTION Small scale vertical axis wind turbines (VAWTs) show potential for urban rooftop turbines. Keywords: Vertical Axis Wind Turbine, VAWT, airfoil, pitch, blade, mount, offset, high solidity

Tullis, Stephen

44

Structural Testing of 9 m Carbon Fiber Wind Turbine Research Blades: Preprint  

DOE Green Energy (OSTI)

This paper outlines the results of tests conducted on three 9-m carbon fiber wind turbine blades designed through a research program initiated by Sandia National Laboratories.

Paquette, J.; van Dam, J.; Hughes, S.

2007-01-01T23:59:59.000Z

45

Experimental Study of Stability Limits for Slender Wind Turbine Blades.  

E-Print Network (OSTI)

??There is a growing interest in extracting more power per turbine by increasing the rotor size in offshore wind turbines. As a result, the turbine (more)

Ladge, Shruti

2012-01-01T23:59:59.000Z

46

PREDICTION OF DELAM INATION IN WIND TURBINE BLADE STRUCTURAL DETAILS John F. Mandell, Douglas S. Cairns  

E-Print Network (OSTI)

in Reference 3, available on the Sandia web site www.sandia.gov/Renewable_Energy/Wind_Energy/. DELAMINATION1 PREDICTION OF DELAM INATION IN WIND TURBINE BLADE STRUCTURAL DETAILS John F. Mandell, Douglas S materials structures such as wind turbine blades. Design methodologies to prevent such failures have

47

Design studies for twist-coupled wind turbine blades.  

SciTech Connect

This study presents results obtained for four hybrid designs of the Northern Power Systems (NPS) 9.2-meter prototype version of the ERS-100 wind turbine rotor blade. The ERS-100 wind turbine rotor blade was designed and developed by TPI composites. The baseline design uses e-glass unidirectional fibers in combination with {+-}45-degree and random mat layers for the skin and spar cap. This project involves developing structural finite element models of the baseline design and carbon hybrid designs with and without twist-bend coupling. All designs were evaluated for a unit load condition and two extreme wind conditions. The unit load condition was used to evaluate the static deflection, twist and twist-coupling parameter. Maximum deflections and strains were determined for the extreme wind conditions. Linear and nonlinear buckling loads were determined for a tip load condition. The results indicate that carbon fibers can be used to produce twist-coupled designs with comparable deflections, strains and buckling loads to the e-glass baseline.

Valencia, Ulyses (Wichita State University, Wichita, KS); Locke, James (Wichita State University, Wichita, KS)

2004-06-01T23:59:59.000Z

48

Incipient Crack Detection in Composite Wind Turbine Blades  

DOE Green Energy (OSTI)

This paper presents some analysis results for incipient crack detection in a 9-meter CX-100 wind turbine blade that underwent fatigue loading to failure. The blade was manufactured to standard specifications, and it underwent harmonic excitation at its first resonance using a hydraulically-actuated excitation system until reaching catastrophic failure. This work investigates the ability of an ultrasonic guided wave approach to detect incipient damage prior to the surfacing of a visible, catastrophic crack. The blade was instrumented with piezoelectric transducers, which were used in an active, pitchcatch mode with guided waves over a range of excitation frequencies. The performance results in detecting incipient crack formation in the fiberglass skin of the blade is assessed over the range of frequencies in order to determine the point at which the incipient crack became detectable. Higher excitation frequencies provide consistent results for paths along the rotor blade's carbon fiber spar cap, but performance falls off with increasing excitation frequencies for paths off of the spar cap. Lower excitation frequencies provide more consistent performance across all sensor paths.

Taylor, Stuart G. [Los Alamos National Laboratory; Choi, Mijin [Chonbuk National University, Korea; Jeong, Hyomi [Chonbuk National University, Korea; Jang, Jae Kyeong [Chonbuk National University, Korea; Park, Gyuhae [Chonnam National University, Korea; Farinholt, Kevin [Commonwealth Center for Advanced Manufacturing, VA; Farrar, Charles R. [Los Alamos National Laboratory; Ammerman, Curtt N. [Los Alamos National Laboratory; Todd, Michael D. [Los Alamos National Laboratory; Lee, Jung-Ryul [Chonbuk National University, Korea

2012-08-28T23:59:59.000Z

49

Blade System Design Studies Volume I: Composite Technologies for Large Wind Turbine Blades  

DOE Green Energy (OSTI)

As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts LLC (GEC) is performing a study concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The project team for this work includes experts in all areas of wind turbine blade design, analysis, manufacture, and testing. Constraints to cost-effective scaling-up of the current commercial blade designs and manufacturing methods are identified, including self-gravity loads, transportation, and environmental considerations. A trade-off study is performed to evaluate the incremental changes in blade cost, weight, and stiffness for a wide range of composite materials, fabric types, and manufacturing processes. Fiberglass/carbon fiber hybrid blades are identified as having a promising combination of cost, weight, stiffness and fatigue resistance. Vacuum-assisted resin transfer molding, resin film infision, and pre-impregnated materials are identified as having benefits in reduced volatile emissions, higher fiber content, and improved laminate quality relative to the baseline wet lay-up process. Alternative structural designs are identified, including jointed configurations to facilitate transportation. Based on the results to date, recommendations are made for further evaluation and testing under this study to verify the predicted material and structural performance.

GRIFFIN, DAYTON A.; ASHWILL, THOMAS D.

2002-07-01T23:59:59.000Z

50

Blade System Design Studies Volume I: Composite Technologies for Large Wind Turbine Blades  

SciTech Connect

As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts LLC (GEC) is performing a study concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The project team for this work includes experts in all areas of wind turbine blade design, analysis, manufacture, and testing. Constraints to cost-effective scaling-up of the current commercial blade designs and manufacturing methods are identified, including self-gravity loads, transportation, and environmental considerations. A trade-off study is performed to evaluate the incremental changes in blade cost, weight, and stiffness for a wide range of composite materials, fabric types, and manufacturing processes. Fiberglass/carbon fiber hybrid blades are identified as having a promising combination of cost, weight, stiffness and fatigue resistance. Vacuum-assisted resin transfer molding, resin film infision, and pre-impregnated materials are identified as having benefits in reduced volatile emissions, higher fiber content, and improved laminate quality relative to the baseline wet lay-up process. Alternative structural designs are identified, including jointed configurations to facilitate transportation. Based on the results to date, recommendations are made for further evaluation and testing under this study to verify the predicted material and structural performance.

GRIFFIN, DAYTON A.; ASHWILL, THOMAS D.

2002-07-01T23:59:59.000Z

51

The new Wind Technology Test Center is the only facility in the nation capable of testing wind turbine blades up to  

E-Print Network (OSTI)

turbine blades up to 90 meters in length. A critical factor to wind turbine design and development is the ability to test new designs, components, and materials. In addition, wind turbine blade manufacturers the blades millions of times to simulate what a blade goes through in its lifetime on a wind turbine

52

Simulation of winds as seen by a rotating vertical axis wind turbine blade  

DOE Green Energy (OSTI)

The objective of this report is to provide turbulent wind analyses relevant to the design and testing of Vertical Axis Wind Turbines (VAWT). A technique was developed for utilizing high-speed turbulence wind data from a line of seven anemometers at a single level to simulate the wind seen by a rotating VAWT blade. Twelve data cases, representing a range of wind speeds and stability classes, were selected from the large volume of data available from the Clayton, New Mexico, Vertical Plane Array (VPA) project. Simulations were run of the rotationally sampled wind speed relative to the earth, as well as the tangential and radial wind speeds, which are relative to the rotating wind turbine blade. Spectral analysis is used to compare and assess wind simulations from the different wind regimes, as well as from alternate wind measurement techniques. The variance in the wind speed at frequencies at or above the blade rotation rate is computed for all cases, and is used to quantitatively compare the VAWT simulations with Horizontal Axis Wind Turbine (HAWT) simulations. Qualitative comparisons are also made with direct wind measurements from a VAWT blade.

George, R.L.

1984-02-01T23:59:59.000Z

53

Wind turbine composite blade manufacturing : the need for understanding defect origins, prevalence, implications and reliability.  

DOE Green Energy (OSTI)

Renewable energy is an important element in the US strategy for mitigating our dependence on non-domestic oil. Wind energy has emerged as a viable and commercially successful renewable energy source. This is the impetus for the 20% wind energy by 2030 initiative in the US. Furthermore, wind energy is important on to enable a global economy. This is the impetus for such rapid, recent growth. Wind turbine blades are a major structural element of a wind turbine blade. Wind turbine blades have near aerospace quality demands at commodity prices; often two orders of magnitude less cost than a comparable aerospace structure. Blade failures are currently as the second most critical concern for wind turbine reliability. Early blade failures typically occur at manufacturing defects. There is a need to understand how to quantify, disposition, and mitigate manufacturing defects to protect the current wind turbine fleet, and for the future. This report is an overview of the needs, approaches, and strategies for addressing the effect of defects in wind turbine blades. The overall goal is to provide the wind turbine industry with a hierarchical procedure for addressing blade manufacturing defects relative to wind turbine reliability.

Cairns, Douglas S. (Montana State University, Bozeman, MT); Riddle, Trey (Montana State University, Bozeman, MT); Nelson, Jared (Montana State University, Bozeman, MT)

2011-02-01T23:59:59.000Z

54

Modal testing of the TX-100 wind turbine blade.  

DOE Green Energy (OSTI)

This test report covers the SNL modal test results for two nominally identical TX-100 wind turbine blades. The TX-100 blade design is unique in that it features a passive braking, force-shedding mechanism where bending and torsion are coupled to produce desirable aerodynamic characteristics. A specific aim of this test is to characterize the coupling between bending and torsional dynamics. The results of the modal tests and the subsequent analysis characterize the natural frequencies, damping, and mode shapes of the individual blades. The results of this report are expected to be used for model validation--the frequencies and mode shapes from the experimental analysis can be compared with those of a finite-element analysis. Damping values are included in the results of these tests to potentially improve the fidelity of numerical simulations, although numerical finite element models typically have no means of predicting structural damping characteristics. Thereafter, an additional objective of the test is achieved in evaluating the test to test and unit variation in the modal parameters of the two blades.

Reese, Sarah; Griffith, Daniel Todd; Casias, Miguel; Simmermacher, Todd William; Smith, Gregory A.

2006-05-01T23:59:59.000Z

55

Aluminum-blade development for the Mod-0A 200-kilowatt wind turbine  

DOE Green Energy (OSTI)

This report documents the operating experience with two aluminum blades used on the DOE/NASA Mod-0A 200-kilowatt wind turbine located at Clayton, New Mexico. Each Mod-0A aluminum blade is 59.9 feet long and weighs 2360 pounds. The aluminum Mod-0A blade design requirements, the selected design, fabrication procedures, and the blade analyses are discussed. A detailed chronology is presented on the operating experience of the Mod-0A aluminum blades used at Clayton, New Mexico. Blade structural damage was experienced. Inspection and damage assessment were required. Structural modifications that were incorporated to the blades successfully extended the useful operating life of the blades. The aluminum blades completed the planned 2 years of operation of the Clayton wind turbine. The blades were removed from service in August 1980 to allow testing of advanced technology wood composite blades.

Linscott, B.S.; Shaltens, R.K.; Eggers, A.G.

1981-12-01T23:59:59.000Z

56

Composite Wind Turbine Blade Effects of Defects: Part B--Progressive Damage Modeling of Fiberglass/Epoxy  

E-Print Network (OSTI)

Composite Wind Turbine Blade Effects of Defects: Part B-- Progressive Damage Modeling of Fiberglass for the reliability of modern composite wind turbine blades. The DOE has sponsored a comprehensive study to a wind turbine blade reliability infrastructure. To support this development of a reliability

57

Reduced Order Structural Modeling of Wind Turbine Blades  

E-Print Network (OSTI)

Conventional three dimensional structural analysis methods prove to be expensive for the preliminary design of wind turbine blades. However, wind turbine blades are large slender members with complex cross sections. They can be accurately modeled using beam models. The accuracy in the predictions of the structural behavior using beam models depends on the accuracy in the prediction of their effective section properties. Several techniques were proposed in the literature for predicting the effective section properties. Most of these existing techniques have limitations because of the assumptions made in their approaches. Two generalized beam theories, Generalized Timoshenko and Generalized Euler-Bernoulli, for the static analysis based on the principles of the simple 1D-theories are developed here. Homogenization based on the strain energy equivalence principle is employed to predict the effective properties for these generalized beam theories. Two efficient methods, Quasi-3D and Unit Cell, are developed which can accurately predict the 3D deformations in beams under the six fundamental deformation modes: extension, two shears, torsion and two flexures. These methods help in predicting the effective properties using the homogenization technique. Also they can recover the detailed 3D deformations from the predictions of 1D beam analysis. The developed tools can analyze two types of slender members 1) slender members with invariant geometric features along the length and 2) slender members with periodically varying geometric features along the length. Several configurations were analyzed for the effective section properties and the predictions were validated using the expensive 3D analysis, strength of materials and Variational Asymptotic Beam Section Analysis (VABS). The predictions from the new tools showed excellent agreement with full 3D analysis. The predictions from the strength of materials showed disagreement in shear and torsional properties. Explanations for the same are provided recalling the assumptions made in the strength of materials approach.

Jonnalagadda, Yellavenkatasunil

2011-08-01T23:59:59.000Z

58

Sinomatech Wind Power Blade aka Sinoma Science Technology Wind...  

Open Energy Info (EERE)

Sinomatech Wind Power Blade aka Sinoma Science Technology Wind Turbine Blade Co Ltd Jump to: navigation, search Name Sinomatech Wind Power Blade (aka Sinoma Science & Technology...

59

Wuxi Bamboo Wind Turbine Blade Technology Co Ltd | Open Energy Information  

Open Energy Info (EERE)

Wuxi Bamboo Wind Turbine Blade Technology Co Ltd Wuxi Bamboo Wind Turbine Blade Technology Co Ltd Jump to: navigation, search Name Wuxi Bamboo Wind Turbine Blade Technology Co Ltd Place Wuxi, Jiangsu Province, China Sector Wind energy Product Chinese wind turbine blade manufacturer. Coordinates 31.574011°, 120.288223° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":31.574011,"lon":120.288223,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

60

Structural damage identification in wind turbine blades using piezoelectric active sensing with ultrasonic validation  

SciTech Connect

This paper gives a brief overview of a new project at LANL in structural damage identification for wind turbines. This project makes use of modeling capabilities and sensing technology to understand realistic blade loading on large turbine blades, with the goal of developing the technology needed to automatically detect early damage. Several structural health monitoring (SHM) techniques using piezoelectric active materials are being investigated for the development of wireless, low power sensors that interrogate sections of the wind turbine blade using Lamb wave propagation data, frequency response functions (FRFs), and time-series analysis methods. The modeling and sensor research will be compared with extensive experimental testing, including wind tunnel experiments, load and fatigue tests, and ultrasonic scans - on small- to mid-scale turbine blades. Furthermore, this study will investigate the effect of local damage on the global response of the blade by monitoring low-frequency response changes.

Claytor, Thomas N [Los Alamos National Laboratory; Ammerman, Curtt N [Los Alamos National Laboratory; Park, Gyu Hae [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Farrar, Charles R [Los Alamos National Laboratory; Atterbury, Marie K [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

WindPACT Turbine Design Scaling Studies Technical Area 2: Turbine, Rotor and Blade Logistics  

SciTech Connect

Through the National Renewable Energy Laboratory (NREL), the United States Department of Energy (DOE) implemented the Wind Partnership for Advanced Component Technologies (WindPACT) program. This program will explore advanced technologies that may reduce the cost of energy (COE) from wind turbines. The initial step in the WindPACT program is a series of preliminary scaling studies intended to determine the optimum sizes for future turbines, help define sizing limits for certain critical technologies, and explore the potential for advanced technologies to contribute to reduced COE as turbine scales increase. This report documents the results of Technical Area 2-Turbine Rotor and Blade Logistics. For this report, we investigated the transportation, assembly, and crane logistics and costs associated with installation of a range of multi-megawatt-scale wind turbines. We focused on using currently available equipment, assembly techniques, and transportation system capabilities and limitations to hypothetically transport and install 50 wind turbines at a facility in south-central South Dakota.

Smith, K.

2001-07-16T23:59:59.000Z

62

Approach to the fatigue analysis of vertical-axis wind-turbine blades  

DOE Green Energy (OSTI)

A cursory analysis of the stress history of wind turbine blades indicates that a single stress level at each wind speed does not adequately describe the blade stress history. A statistical description is required. Blade stress data collected from the DOE/ALCOA Low Cost experimental turbines indicate that the Rayleigh probability density function adequately describes the distribution of vibratory stresses at each wind speed. The Rayleigh probability density function allows the distribution of vibratory stresses to be described by the RMS of the stress vs. time signal. With the RMS stress level described for all wind speeds, the complete stress history of the turbine blades is known. Miner's linear cumulative damage rule is used as a basis for summing the fatigue damage over all operating conditions. An analytical expression is derived to predict blade fatigue life.

Veers, P.S.

1981-09-01T23:59:59.000Z

63

Wind energy conversion. Volume X. Aeroelastic stability of wind turbine rotor blades  

DOE Green Energy (OSTI)

The nonlinear equations of motion of a general wind turbine rotor blade are derived from first principles. The twisted, tapered blade may be preconed out of the plane of rotation, and its root may be offset from the axis of rotation by a small amount. The aerodynamic center, center of mass, shear center, and area centroid are distinct in this derivation. The equations are applicable to studies of forced response or of aeroelastic flutter, however, neither gravity forcing, nor wind shear and gust forcing are included. The equations derived are applied to study the aeroelastic stability of the NASA-ERDA 100 kW wind turbine, and solved using the Galerkin method. The numerical results are used in conjunction with a mathematical comparison to prove the validity of an equivalent hinge model developed by the Wind Energy Conversion Project at the Massachusetts Institute of Technology.

Wendell, J.

1978-09-01T23:59:59.000Z

64

Passive aeroelastic tailoring of wind turbine blades : a numerical analysis  

E-Print Network (OSTI)

This research aims to have an impact towards a sustainable energy supply. In wind power generation losses occur at tip speed ratios which the rotor was not designed for. Since the ideal blade shape changes nonlinearly with ...

Deilmann, Christian

2009-01-01T23:59:59.000Z

65

NREL Wind Turbine Blade Structural Testing of the Modular Wind Energy MW45 Blade: Cooperative Research and Development Final Report, CRADA Number CRD-09-354  

DOE Green Energy (OSTI)

This CRADA was a purely funds-in CRADA with Modular Wind Energy (MWE). MWE had a need to perform full-scale testing of a 45-m wind turbine blade. NREL/NWTC provided the capabilities, facilities, and equipment to test this large-scale MWE wind turbine blade. Full-scale testing is required to demonstrate the ability of the wind turbine blade to withstand static design load cases and demonstrate the fatigue durability. Structural testing is also necessary to meet international blade testing certification requirements. Through this CRADA, MWE would obtain test results necessary for product development and certification, and NREL would benefit by working with an industrial partner to better understand the unique test requirements for wind turbine blades with advanced structural designs.

Hughes, S.

2012-05-01T23:59:59.000Z

66

Department of Energy to Invest up to $4 Million for Wind Turbine Blade  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

up to $4 Million for Wind Turbine up to $4 Million for Wind Turbine Blade Testing Facilities Department of Energy to Invest up to $4 Million for Wind Turbine Blade Testing Facilities June 25, 2007 - 2:07pm Addthis New facilities in Massachusetts and Texas will bring cutting-edge technology to wind research WASHINGTON, DC - The U.S. Department of Energy (DOE) Secretary Samuel W. Bodman today announced that DOE has selected the Commonwealth of Massachusetts Partnership in Massachusetts, and the Lone Star Wind Alliance in Texas, to each receive up to $2 million in test equipment to develop large-scale wind blade test facilities, accelerating the commercial availability of wind energy. These consortia have been selected to negotiate cooperative research and development agreements (CRADAs) to

67

Low Speed Technology for Small Turbine Development Reaction Injection Molded 7.5 Meter Wind Turbine Blade  

Science Conference Proceedings (OSTI)

An optimized small turbine blade (7.5m radius) was designed and a partial section molded with the RIM (reaction-injection molded polymer) process for mass production. The intended market is for generic three-bladed wind turbines, 100 kilowatts or less, for grid-assist end users with rural and semi-rural sites, such as the farm/ranch market, having low to moderate IEC Class 3-4 wind regimes. This blade will have substantial performance improvements over, and be cheaper than, present-day 7.5m blades. This is made possible by the injection-molding process, which yields high repeatability, accurate geometry and weights, and low cost in production quantities. No wind turbine blade in the 7.5m or greater size has used this process. The blade design chosen uses a RIM skin bonded to a braided infused carbon fiber/epoxy spar. This approach is attractive to present users of wind turbine blades in the 5-10m sizes. These include rebladeing California wind farms, refurbishing used turbines for the Midwest farm market, and other manufacturers introducing new turbines in this size range.

David M. Wright; DOE Project Officer - Keith Bennett

2007-07-31T23:59:59.000Z

68

Wind Turbine Blade Test Definition of the DeWind DW90 Rotor Blade: Cooperative Research and Development Final Report, CRADA Number CRD-09-326  

DOE Green Energy (OSTI)

This CRADA was developed as a funds-in CRADA with DeWind to assess the suitability of facilities and equipment at the NWTC for performing certification blade testing on wind turbine blades made from advanced materials. DeWind produces a wind turbine blade which includes the use of high-strength and stiffness materials. NREL and DeWind had a mutual interest in defining the necessary facilities, equipment, and test methods for testing large wind turbine blades which incorporate advanced materials and adaptive structures, as the demands on test equipment and infrastructure are greater than current capabilities. Work under this CRADA would enable DeWind to verify domestic capability for certification-class static and fatigue testing, while NREL would be able to identify and develop specialized test capabilities based on the test requirements.

Hughes, S.

2012-05-01T23:59:59.000Z

69

Design and fabrication of a composite wind turbine blade  

SciTech Connect

This paper describes the design considerations leading to the innovative combination of materials used for the MOD-I wind turbine generator rotor and the fabrication processes which were required to accomplish it.

Brown, R.A. (Boeing Engineering and Construction, Seattle, WA); Haley, R.G.

1980-01-01T23:59:59.000Z

70

Recent results from data analysis of dynamic stall on wind turbine blades  

DOE Green Energy (OSTI)

Wind turbines are subjected to dynamic loading from a variety of different sources. Wind shear and turbulence cause time-varying inflow that results in unsteady airloads. Tower shadow, upwind turbine wakes, and yaw angles also introduce unsteady inflow to wind turbine rotors. Wind turbine designers must predict these loads accurately in order to adequately design blades, hubs, and the remaining support structure to achieve a 30-year life. Structural analysts have not been able to predict mean or dynamic loads accurately enough to predict the fatigue life of major wind turbine components with confidence. Part of the problem is due to uncertainty in the stochastic wind environments as mentioned earlier. Another important part of the problem is the lack of basic knowledge of rotary wing airfoil stall performance. There is mounting evidence that dynamic stall may be related to dynamic loads that are greater than predictions. This paper describes some results of investigations of unsteady aerodynamic loads measured on a wind turbine blade. The objective of the investigation is to understand the steady and unsteady stall behavior of wind turbine blades. 13 refs.

Butterfield, C.P.; Simms, D. [National Renewable Energy Lab., Golden, CO (United States); Huyer, S. [Colorado Univ., Boulder, CO (United States)

1992-01-01T23:59:59.000Z

71

Modal analysis and SHM investigation of CX-100 wind turbine blade  

DOE Green Energy (OSTI)

This paper presents the dynamic characterization of a CX-100 wind turbine blade using modal testing. Obtaining a thorough dynamic characterization of turbine blades is important because they are complex structures, making them very difficult to accurately model without supplementing with experimental data. The results of this dynamic characterization can be used to validate a numerical model and understand the effect of structural damage on the performance of the blades. Also covered is an exploration into Structural Health Monitoring (SHM) techniques employed on the blade surface to detect changes in the blade dynamic properties. SHM design parameters such as traveling distance of the wave were examined . Results obtained during modal and SHM testing will provide a baseline for future work in blade damage detection and mitigation.

Deines, Krystal E [Los Alamos National Laboratory; Marinone, Timothy [Los Alamos National Laboratory; Schultz, Ryan A [Los Alamos National Laboratory; Farinholt, Kevin R [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory

2010-11-08T23:59:59.000Z

72

Evaluation of Aeroelastically Tailored Small Wind Turbine Blades Final Project Report  

DOE Green Energy (OSTI)

Evaluation of Aeroelastically Tailored Small Wind Turbine Blades Final Report Global Energy Concepts, LLC (GEC) has performed a conceptual design study concerning aeroelastic tailoring of small wind turbine blades. The primary objectives were to evaluate ways that blade/rotor geometry could be used to enable cost-of-energy reductions by enhancing energy capture while constraining or mitigating blade costs, system loads, and related component costs. This work builds on insights developed in ongoing adaptive-blade programs but with a focus on application to small turbine systems with isotropic blade material properties and with combined blade sweep and pre-bending/pre-curving to achieve the desired twist coupling. Specific goals of this project are to: (A) Evaluate and quantify the extent to which rotor geometry can be used to realize load-mitigating small wind turbine rotors. Primary aspects of the load mitigation are: (1) Improved overspeed safety affected by blades twisting toward stall in response to speed increases. (2) Reduced fatigue loading affected by blade twisting toward feather in response to turbulent gusts. (B) Illustrate trade-offs and design sensitivities for this concept. (C) Provide the technical basis for small wind turbine manufacturers to evaluate this concept and commercialize if the technology appears favorable. The SolidWorks code was used to rapidly develop solid models of blade with varying shapes and material properties. Finite element analyses (FEA) were performed using the COSMOS code modeling with tip-loads and centripetal accelerations. This tool set was used to investigate the potential for aeroelastic tailoring with combined planform sweep and pre-curve. An extensive matrix of design variables was investigated, including aerodynamic design, magnitude and shape of planform sweep, magnitude and shape of blade pre-curve, material stiffness, and rotor diameter. The FEA simulations resulted in substantial insights into the structural response of these blades. The trends were used to identify geometries and rotor configurations that showed the greatest promise for achieving beneficial aeroelastic response. The ADAMS code was used to perform complete aeroelastic simulations of selected rotor configurations; however, the results of these simulations were not satisfactory. This report documents the challenges encountered with the ADAMS simulations and presents recommendations for further development of this concept for aeroelastically tailored small wind turbine blades.

Griffin, Dayton A.

2005-09-29T23:59:59.000Z

73

Fiber-Optic Defect and Damage Locator System for Wind Turbine Blades  

DOE Green Energy (OSTI)

IFOS in collaboration with Auburn University demonstrated the feasibility of a Fiber Bragg Grating (FBG) integrated sensor system capable of providing real time in-situ defect detection, localization and quantification of damage. In addition, the system is capable of validating wind turbine blade structural models, using recent advances in non-contact, non-destructive dynamic testing of composite structures. This new generation method makes it possible to analyze wind turbine blades not only non-destructively, but also without physically contacting or implanting intrusive electrical elements and transducers into the structure. Phase I successfully demonstrated the feasibility of the technology with the construction of a 1.5 kHz sensor interrogator and preliminary instrumentation and testing of both composite material coupons and a wind turbine blade.

Dr. Vahid Sotoudeh; Dr. Richard J. Black; Dr. Behzad Moslehi; Mr. Aleks Plavsic

2010-10-30T23:59:59.000Z

74

Structural health monitoring of wind turbine blades : SE 265 Final Project.  

SciTech Connect

ACME Wind Turbine Corporation has contacted our dynamic analysis firm regarding structural health monitoring of their wind turbine blades. ACME has had several failures in previous years. Examples are shown in Figure 1. These failures have resulted in economic loss for the company due to down time of the turbines (lost revenue) and repair costs. Blade failures can occur in several modes, which may depend on the type of construction and load history. Cracking and delamination are some typical modes of blade failure. ACME warranties its turbines and wishes to decrease the number of blade failures they have to repair and replace. The company wishes to implement a real time structural health monitoring system in order to better understand when blade replacement is necessary. Because of warranty costs incurred to date, ACME is interested in either changing the warranty period for the blades in question or predicting imminent failure before it occurs. ACME's current practice is to increase the number of physical inspections when blades are approaching the end of their fatigue lives. Implementation of an in situ monitoring system would eliminate or greatly reduce the need for such physical inspections. Another benefit of such a monitoring system is that the life of any given component could be extended since real conditions would be monitored. The SHM system designed for ACME must be able to operate while the wind turbine is in service. This means that wireless communication options will likely be implemented. Because blade failures occur due to cyclic stresses in the blade material, the sensing system will focus on monitoring strain at various points.

Barkley, W. C.(Walter C.); Jacobs, Laura D.; Rutherford, A. C.(Amanda C.); Puckett, Anthony

2006-03-23T23:59:59.000Z

75

Structural health monitoring of wind turbine blades : SE 265 Final Project.  

DOE Green Energy (OSTI)

ACME Wind Turbine Corporation has contacted our dynamic analysis firm regarding structural health monitoring of their wind turbine blades. ACME has had several failures in previous years. Examples are shown in Figure 1. These failures have resulted in economic loss for the company due to down time of the turbines (lost revenue) and repair costs. Blade failures can occur in several modes, which may depend on the type of construction and load history. Cracking and delamination are some typical modes of blade failure. ACME warranties its turbines and wishes to decrease the number of blade failures they have to repair and replace. The company wishes to implement a real time structural health monitoring system in order to better understand when blade replacement is necessary. Because of warranty costs incurred to date, ACME is interested in either changing the warranty period for the blades in question or predicting imminent failure before it occurs. ACME's current practice is to increase the number of physical inspections when blades are approaching the end of their fatigue lives. Implementation of an in situ monitoring system would eliminate or greatly reduce the need for such physical inspections. Another benefit of such a monitoring system is that the life of any given component could be extended since real conditions would be monitored. The SHM system designed for ACME must be able to operate while the wind turbine is in service. This means that wireless communication options will likely be implemented. Because blade failures occur due to cyclic stresses in the blade material, the sensing system will focus on monitoring strain at various points.

Barkley, W. C. (Walter C.); Jacobs, Laura D.; Rutherford, A. C. (Amanda C.); Puckett, Anthony

2006-03-23T23:59:59.000Z

76

Survey of techniques for reduction of wind turbine blade trailing edge noise.  

DOE Green Energy (OSTI)

Aerodynamic noise from wind turbine rotors leads to constraints in both rotor design and turbine siting. The primary source of aerodynamic noise on wind turbine rotors is the interaction of turbulent boundary layers on the blades with the blade trailing edges. This report surveys concepts that have been proposed for trailing edge noise reduction, with emphasis on concepts that have been tested at either sub-scale or full-scale. These concepts include trailing edge serrations, low-noise airfoil designs, trailing edge brushes, and porous trailing edges. The demonstrated noise reductions of these concepts are cited, along with their impacts on aerodynamic performance. An assessment is made of future research opportunities in trailing edge noise reduction for wind turbine rotors.

Barone, Matthew Franklin

2011-08-01T23:59:59.000Z

77

Potential for Reducing Blade-Tip Acoustic Emissions for Small Wind Turbines: June 1, 2007 - July 31, 2008  

DOE Green Energy (OSTI)

This report provides results of wind tunnel aroacoustic tests conducted on a small wind turbine blade in the open-jet test section of the Georgia Tech Research Institute Flight Simulation Facility.

Migliore, P.

2009-02-01T23:59:59.000Z

78

Mechanical Design, Analysis, and Testing of a Two-Bladed Wind Turbine Hub  

DOE Green Energy (OSTI)

Researchers at the National Wind Technology Center (NWTC) in Golden, Colorado, began performing the Unsteady Aerodynamics Experiment in 1993 to better understand the unsteady aerodynamics and structural responses of horizontal-axis wind turbines. The experiment consists of an extensively instrumented, downwind, three-bladed, 20-kilowatt wind turbine. In May 1995, I received a request from the NWTC to design a two-bladed hub for the experiment. For my thesis, I present the results of the mechanical design, analysis, and testing of the hub. The hub I designed is unique because it runs in rigid, teetering, or independent blade-flapping modes. In addition, the design is unusual because it uses two servomotors to pitch the blades independently. These features are used to investigate new load reduction, noise reduction, blade pitch optimization, and yaw control techniques for two-bladed turbines. I used a methodology by G. Phal and W. Bietz to design the hub. The hub meets all the performance specifications except that it achieves only 90% of the specified teeter range. In my thesis, I focus on the analysis and testing of the hub body. I performed solid-mechanics calculations, ran a finite-element analysis simulation, and experimentally investigated the structural integrity of the hub body.

Cotrell, J.

2002-06-01T23:59:59.000Z

79

Application of the U.S. high cycle fatigue data base to wind turbine blade lifetime predictions  

DOE Green Energy (OSTI)

This paper demonstrates a methodology for predicting the service lifetime of wind turbine blades using the high-cycle fatigue data base for typical U.S. blade materials developed by Mandell, et al. (1995). The first step in the analysis is to normalize the data base (composed primarily of data obtained from specialized, relatively small coupons) with fatigue data from typical industrial laminates to obtain a Goodman Diagram that is suitable for analyzing wind turbine blades. The LIFE2 fatigue analysis code for wind turbines is then used for the fatigue analysis of a typical turbine blade with a known load spectrum. In the analysis, a linear damage model, Miner`s Rule, is used to demonstrate the prediction of the service lifetime for a typical wind turbine blade under assumed operating strain ranges and stress concentration factors. In contrast to typical European data, the asymmetry in this data base predicts failures under typical loads to be compressive.

Sutherland, H.J. [Sandia National Labs., Albuquerque, NM (United States); Mandell, J.F. [Montana State Univ., Bozeman, MT (United States)

1995-12-01T23:59:59.000Z

80

Effects of blade configurations on flow distribution and power output of a Zephyr vertical axis wind turbine  

Science Conference Proceedings (OSTI)

Numerical simulations with FLUENT software were conducted to investigate the fluid flow through a novel vertical axis wind turbine (VAWT). Simulation of flow through the turbine rotor was performed with the aim of predicting the performance characteristics ... Keywords: blade configuration, power output, rotor, simulation, vertical axis wind turbine

J. O. Ajedegba; G. F. Naterer; M. A. Rosen; E. Tsang

2008-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Guidelines for reducing dynamic loads in two-bladed teetering-hub downwind wind turbines  

DOE Green Energy (OSTI)

A major goal of the federal Wind Energy Program is the rapid development and validation of structural models to determine loads and response for a wide variety of different wind turbine configurations operating under extreme conditions. Such codes are crucial to the successful design of future advanced wind turbines. In previous papers the authors described steps they took to develop a model of a two-bladed teetering-hub downwind wind turbine using ADAMS{reg_sign} (Automatic Dynamic Analysis of Mechanical Systems), as well as comparison of model predictions to test data. In this paper they show the use of this analytical model to study the influence of various turbine parameters on predicted system loads. They concentrate their study on turbine response in the frequency range of six to ten times the rotor rotational frequency (6P to 10P). Their goal is to identify the most important parameters which influence the response of this type of machine in this frequency range and give turbine designers some general design guidelines for designing two-bladed teetering-hub machines to be less susceptible to vibration. They study the effects of such parameters as blade edgewise and flapwise stiffness, tower top stiffness, blade tip-brake mass, low-speed shaft stiffness, nacelle mass momenta of inertia, and rotor speed. They show which parameters can be varied in order to make the turbine less responsive to such atmospheric inputs as wind shear and tower shadow. They then give designers a set of design guidelines in order to show how these machines can be designed to be less responsive to these inputs.

Wright, A.D.; Bir, G.S.; Butterfield, C.D.

1995-06-01T23:59:59.000Z

82

Modal analysis and SHM investigation of CX-100 wind turbine blade  

DOE Green Energy (OSTI)

This paper presents the dynamic characterization of a CX100 blade using modal testing. Obtaining a thorough dynamic characterization of these turbine blades is important because they are complex structures, making them difficult to monitor for damage initiation and subsequent growth. This dynamic characterization was compared to a numerical model developed for validation. Structural Health Monitoring (SHM) techniques involving Lamb wave propagation, frequency response functions, and impedance based methods were also used to provide insight into blade dynamic response. SHM design parameters such as traveling distance of the wave, sensing region of the sensor and the power requirements were examined. Results obtained during modal and SHM testing will provide a baseline for future damage detection and mitigation techniques for wind turbine blades.

Deines, Krystal E [Los Alamos National Laboratory; Marinone, Timothy [Los Alamos National Laboratory; Schultz, Ryan A [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory

2011-01-24T23:59:59.000Z

83

The application of non-destructive techniques to the testing of a wind turbine blade  

DOE Green Energy (OSTI)

NonDestructive Testing (NDT), also called NonDestructive Evaluation (NDE), is commonly used to monitor structures before, during, and after testing. This paper reports on the use of two NDT techniques to monitor the behavior of a typical wind turbine blade during a quasi-static test-to-failure. The two NDT techniques used were acoustic emission and coherent optical. The former monitors the acoustic energy produced by the blade as it is loaded. The latter uses electron shearography to measure the differences in surface displacements between two load states. Typical results are presented to demonstrate the ability of these two techniques to locate and monitor both high damage regions and flaws in the blade structure. Furthermore, this experiment highlights the limitations in the techniques that must be addressed before one or both can be transferred, with a high probability of success, to the inspection and monitoring of turbine blades during the manufacturing process and under normal operating conditions.

Sutherland, H.; Beattie, A.; Hansche, B. [Sandia National Labs., Albuquerque, NM (United States); Musial, W.; Allread, J.; Johnson, J. [National Renewable Energy Lab., Golden, CO (United States); Summers, M. [United Technologies, West Palm Beach, FL (United States)

1994-06-01T23:59:59.000Z

84

Fatigue of Composite Material Beam Elements Representative of Wind Turbine Blade Substructure  

DOE Green Energy (OSTI)

The database and analysis methods used to predict wind turbine blade structural performance for stiffness, static strength, dynamic response,and fatigue lifetime are validated through the design, fabrication, and testing of substructural elements. We chose a test specimen representative of wind turbine blade primary substructure to represent the spar area of a typical wind turbine blade. We then designed an I-beam with flanges and web to represent blade structure, using materials typical of many U.S.-manufactured blades. Our study included the fabrication and fatigue testing of 52 beams and many coupons of beam material. Fatigue lifetimes were consistent with predictions based on the coupon database. The final beam specimen proved to be a very useful tool for validating strength and lifetime predictions for a variety of flange and web materials, and is serving as a test bed to ongoing studies of structural details and the interaction between manufacturing and structural performance. Th e beam test results provide a significant validation of the coupon database and the methodologies for predicting fatigue of composite material beam elements.

Mandell, J. F.; Samborsky, D. D.; Combs, D. W.; Scott, M. E.; Cairns, D. S. (Department of Chemical Engineering, Montana State University)

1998-01-11T23:59:59.000Z

85

Wind turbine blade fatigue tests: lessons learned and application to SHM system development  

DOE Green Energy (OSTI)

This paper presents experimental results of several structural health monitoring (SHM) methods applied to a 9-meter CX-100 wind turbine blade that underwent fatigue loading. The blade was instrumented with piezoelectric transducers, accelerometers, acoustic emission sensors, and foil strain gauges. It underwent harmonic excitation at its first natural frequency using a hydraulically actuated resonant excitation system. The blade was initially excited at 25% of its design load, and then with steadily increasing loads until it failed. Various data were collected between and during fatigue loading sessions. The data were measured over multiple frequency ranges using a variety of acquisition equipment, including off-the-shelf systems and specially designed hardware developed by the authors. Modal response, diffuse wave-field transfer functions, and ultrasonic guided wave methods were applied to assess the condition of the wind turbine blade. The piezoelectric sensors themselves were also monitored using a sensor diagnostics procedure. This paper summarizes experimental procedures and results, focusing particularly on fatigue crack detection, and concludes with considerations for implementing such damage identification systems, which will be used as a guideline for future SHM system development for operating wind turbine blades.

Taylor, Stuart G. [Los Alamos National Laboratory; Farinholt, Kevin M. [Los Alamos National Laboratory; Jeong, Hyomi [Chonbuk National University, Korea; Jang, JaeKyung [Chonbuk National University, Korea; Park, Gyu Hae [Los Alamos National Laboratory; Todd, Michael D. [Los Alamos National Laboratory; Farrar, Charles R. [Los Alamos National Laboratory; Ammerman, Curtt N. [Los Alamos National Laboratory

2012-06-28T23:59:59.000Z

86

Design of a 3 kW wind turbine generator with thin airfoil blades  

SciTech Connect

Three blades of a 3 kW prototype wind turbine generator were designed with thin airfoil and a tip speed ratio of 3. The wind turbine has been controlled via two control methods: the variable pitch angle and by regulation of the field current of the generator and examined under real wind conditions. The characteristics of the thin airfoil, called ''Seven arcs thin airfoil'' named so because the airfoil is composed of seven circular arcs, are analyzed with the airfoil design and analysis program XFOIL. The thin airfoil blade is designed and calculated by blade element and momentum theory. The performance characteristics of the machine such as rotational speed, generator output as well as stability for wind speed changes are described. In the case of average wind speeds of 10 m/s and a maximum of 19 m/s, the automatically controlled wind turbine ran safely through rough wind conditions and showed an average generator output of 1105 W and a power coefficient 0.14. (author)

Ameku, Kazumasa; Nagai, Baku M.; Roy, Jitendro Nath [Faculty of Mechanical Engineering, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Okinawa 903-0213 (Japan)

2008-09-15T23:59:59.000Z

87

Wind turbine  

DOE Patents (OSTI)

A wind turbine of the type having an airfoil blade (15) mounted on a flexible beam (20) and a pitch governor (55) which selectively, torsionally twists the flexible beam in response to wind turbine speed thereby setting blade pitch, is provided with a limiter (85) which restricts unwanted pitch change at operating speeds due to torsional creep of the flexible beam. The limiter allows twisting of the beam by the governor under excessive wind velocity conditions to orient the blades in stall pitch positions, thereby preventing overspeed operation of the turbine. In the preferred embodiment, the pitch governor comprises a pendulum (65,70) which responds to changing rotor speed by pivotal movement, the limiter comprising a resilient member (90) which engages an end of the pendulum to restrict further movement thereof, and in turn restrict beam creep and unwanted blade pitch misadjustment.

Cheney, Jr., Marvin C. (Glastonbury, CT)

1982-01-01T23:59:59.000Z

88

Application of piezoelectric active-sensors for SHM of wind turbine blades  

DOE Green Energy (OSTI)

The goal of this study is to characterize the dynamic response of a CX-100 wind blade and the design parameters of SHM techniques as they apply to wind turbine blades, and to investigate the performance of high-frequency active-sensing SHM techniques, including lamb wave and frequency response functions, as a way to monitor the health of a wind turbine blade. The results of the dynamic characterization will be used to validate a numerical model and understand the effect of structural damage on the performance of the blades. The focus of SHM study is to assess and compare the performance of each method in identifying incipient damage, with a special consideration given to field deployability. For experiments, a 9-m CX-100 blade was used. Overall, the methods yielded sufficient damage detection to warrant further investigation into field deployment. This paper also summarizes the SHM results of a full-scale fatigue test of 9-m CX-100 blade using piezoelectric active-sensors.

Park, Gyuhae [Los Alamos National Laboratory; Taylor, Stuart G. [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Farrar, Charles R [Los Alamos National Laboratory

2010-10-04T23:59:59.000Z

89

Fatigue Testing of 9 m Carbon Fiber Wind Turbine Research Blades  

SciTech Connect

Fatigue testing was conducted on Carbon Experimental and Twist-Bend Experimental (CX-100 and TX-100) 9-m wind turbine research blades. The CX-100 blade was designed to investigate the use of a carbon spar cap to reduce weight and increase stiffness while being incorporated using conventional manufacturing techniques. The TX-100 blade used carbon in the outboard portion of the skin to produce twist-bend coupling to passively alleviate aerodynamic loads. In the fatigue tests, the CX-100 blade was loaded by a single hydraulic cylinder while the TX-100 blade was loaded via a hydraulically-actuated resonant loading system called the Universal Resonant Exciter. The blades were outfitted with approximately 30 strain gages as well as displacement and load sensors. Both blades survived to cycle counts sufficient to demonstrate a 20-year operational life. The CX-100 blade failed at approximately 1.6 million cycles because of a buckle and crack that formed and grew just outboard of max-chord. The TX-100 blade failed because of a crack that grew from the termination point of the spar cap at the midspan of the blade. This paper covers the results of the fatigue tests.

Paquette, J.; van Dam, J.; Hughes, S.; Johnson, J.

2008-01-01T23:59:59.000Z

90

ADVANCED COMPOSITE WIND TURBINE BLADE DESIGN BASED ON DURABILITY AND DAMAGE TOLERANCE  

Science Conference Proceedings (OSTI)

The objective of the program was to demonstrate and verify Certification-by-Analysis (CBA) capability for wind turbine blades made from advanced lightweight composite materials. The approach integrated durability and damage tolerance analysis with robust design and virtual testing capabilities to deliver superior, durable, low weight, low cost, long life, and reliable wind blade design. The GENOA durability and life prediction software suite was be used as the primary simulation tool. First, a micromechanics-based computational approach was used to assess the durability of composite laminates with ply drop features commonly used in wind turbine applications. Ply drops occur in composite joints and closures of wind turbine blades to reduce skin thicknesses along the blade span. They increase localized stress concentration, which may cause premature delamination failure in composite and reduced fatigue service life. Durability and damage tolerance (D&DT) were evaluated utilizing a multi-scale micro-macro progressive failure analysis (PFA) technique. PFA is finite element based and is capable of detecting all stages of material damage including initiation and propagation of delamination. It assesses multiple failure criteria and includes the effects of manufacturing anomalies (i.e., void, fiber waviness). Two different approaches have been used within PFA. The first approach is Virtual Crack Closure Technique (VCCT) PFA while the second one is strength-based. Constituent stiffness and strength properties for glass and carbon based material systems were reverse engineered for use in D&DT evaluation of coupons with ply drops under static loading. Lamina and laminate properties calculated using manufacturing and composite architecture details matched closely published test data. Similarly, resin properties were determined for fatigue life calculation. The simulation not only reproduced static strength and fatigue life as observed in the test, it also showed composite damage and fracture modes that resemble those reported in the tests. The results show that computational simulation can be relied on to enhance the design of tapered composite structures such as the ones used in turbine wind blades. A computational simulation for durability, damage tolerance (D&DT) and reliability of composite wind turbine blade structures in presence of uncertainties in material properties was performed. A composite turbine blade was first assessed with finite element based multi-scale progressive failure analysis to determine failure modes and locations as well as the fracture load. D&DT analyses were then validated with static test performed at Sandia National Laboratories. The work was followed by detailed weight analysis to identify contribution of various materials to the overall weight of the blade. The methodology ensured that certain types of failure modes, such as delamination progression, are contained to reduce risk to the structure. Probabilistic analysis indicated that composite shear strength has a great influence on the blade ultimate load under static loading. Weight was reduced by 12% with robust design without loss in reliability or D&DT. Structural benefits obtained with the use of enhanced matrix properties through nanoparticles infusion were also assessed. Thin unidirectional fiberglass layers enriched with silica nanoparticles were applied to the outer surfaces of a wind blade to improve its overall structural performance and durability. The wind blade was a 9-meter prototype structure manufactured and tested subject to three saddle static loading at Sandia National Laboratory (SNL). The blade manufacturing did not include the use of any nano-material. With silica nanoparticles in glass composite applied to the exterior surfaces of the blade, the durability and damage tolerance (D&DT) results from multi-scale PFA showed an increase in ultimate load of the blade by 9.2% as compared to baseline structural performance (without nano). The use of nanoparticles lead to a delay in the onset of delamination. Load-displacement relati

Galib Abumeri; Frank Abdi (PhD)

2012-02-16T23:59:59.000Z

91

Fluid flow modeling of resin transfer molding for composite material wind turbine blade structures.  

SciTech Connect

Resin transfer molding (RTM) is a closed mold process for making composite materials. It has the potential to produce parts more cost effectively than hand lay-up or other methods. However, fluid flow tends to be unpredictable and parts the size of a wind turbine blade are difficult to engineer without some predictive method for resin flow. There were five goals of this study. The first was to determine permeabilities for three fabrics commonly used for RTM over a useful range of fiber volume fractions. Next, relations to estimate permeabilities in mixed fabric lay-ups were evaluated. Flow in blade substructures was analyzed and compared to predictions. Flow in a full-scale blade was predicted and substructure results were used to validate the accuracy of a full-scale blade prediction.

Cairns, Douglas S. (Montana State University, Bozeman, MT); Rossel, Scott M. (Montana State University, Bozeman, MT)

2004-06-01T23:59:59.000Z

92

Evaluation of Hand Lay-Up and Resin Transfer Molding in Composite Wind Turbine Blade Manufacturing  

DOE Green Energy (OSTI)

The majority of the wind turbine blade industry currently uses low cost hand lay-up manufacturing techniques to process composite blades. While there are benefits to the hand lay-up process, drawbacks inherent to this process along with advantages of other techniques suggest that better manufacturing alternatives may be available. Resin Transfer Molding (RTM) was identified as a processing alternative and shows promise in addressing the shortcomings of hand lay-up. This report details a comparison of the RTM process to hand lay-up of composite wind turbine blade structures. Several lay-up schedules and critical turbine blade structures were chosen for comparison of their properties resulting from RTM and hand lay-up processing. The geometries investigated were flat plate, thin and thick flanged T-stiffener, I-beam, and root connection joint. It was found that the manufacturing process played an important role in laminate thickness, fiber volume, and weight for the geometries investigated. RTM was found to reduce thickness and weight and increase fiber volumes for all substructures. RTM resulted in tighter material transition radii and eliminated the need for most secondary bonding operations. These results would significantly reduce the weight of wind turbine blades. Hand lay-up was consistently slower in fabrication times for the structures investigated. A comparison of mechanical properties showed no significant differences after employing fiber volume normalization techniques to account for geometry differences resulting from varying fiber volumes. The current root specimen design does not show significant mechanical property differences according to process and exceeds all static and fatigue requirements.

CAIRNS,DOUGLAS S.; SHRAMSTAD,JON D.

2000-06-01T23:59:59.000Z

93

Lidar measurement of wind velocity turbulence spectra encountered by a rotating turbine blade  

DOE Green Energy (OSTI)

A homodyne CO/sub 2/ lidar system beam was conically scanned around a horizontal axis to measure the wind speed and turbulence characteristics encountered by a rotating turbine blade. Turbulence spectra obtained from the scanning lidar differed considerably from those calculated from fixed-point anemometer measurements, showing a redistribution of energy from lower to higher frequencies. The differences appeared more pronounced during periods when the atmosphere was stable.

Hardesty, R.M.; Korrell, J.A.; Hall, F.F. Jr.

1982-01-01T23:59:59.000Z

94

Energy Basics: Wind Turbines  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Photo of a crane lifting the blades onto a wind turbine that reads 'U.S. Department of Energy, NREL.' You can learn more about horizontal axis turbines from the EERE Wind Program's...

95

The application of nondestructive techniques to the testing of a wind turbine blade  

DOE Green Energy (OSTI)

NonDestructive Testing (NDT) is commonly used to monitor structures before, during and after testing. This paper reports on the use of two NDT techniques to monitor the behavior of a typical wind turbine blade during a quasi-static test-to-failure. The test used a three-point spanwise load distribution to load a 7.9-m blade to failure. The two NDT techniques used were acoustic emission and coherent optical. The former monitors the acoustic energy produced by the blade as it is loaded. The latter uses electronic shearography to measure the differences in surface displacements between two load states with an accuracy of a few microns. Typical results are presented to demonstrate the ability of these two techniques to locate and monitor both high damage regions and flaws in the blade structure. Further, this experiment highlights the limitations in the techniques that must be addressed before one or both can be transferred, with a high probability of success, to the inspection and monitoring of turbine blades during the manufacturing process and under normal operating conditions.

Sutherland, H.J. [Sandia National Labs., Albuquerque, NM (US); Musial, W. [National Renewable Energy Lab., Golden, CO (US)

1993-07-01T23:59:59.000Z

96

Wind turbine rotor blade with in-plane sweep and devices using same, and methods for making same  

DOE Patents (OSTI)

A wind turbine includes a rotor having a hub and at least one blade having a torsionally rigid root, an inboard section, and an outboard section. The inboard section has a forward sweep relative to an elastic axis of the blade and the outboard section has an aft sweep.

Wetzel, Kyle Kristopher (Lawrence, KS)

2008-03-18T23:59:59.000Z

97

Pages that link to "Tianjin Dongqi Wind Turbine Blade Engineering...  

Open Energy Info (EERE)

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98

Pages that link to "Wuxi Bamboo Wind Turbine Blade Technology...  

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99

A Comparison of Two and Three Bladed Floating Wind Turbines.  

E-Print Network (OSTI)

??A possible solution to the limitations of current offshore wind technology would be the utilization of a floating platform. Floating platforms are not a new (more)

Andersen, Brett

2010-01-01T23:59:59.000Z

100

Wind Turbine Blade Flow Fields and Prospects for Active Aerodynamic Control: Preprint  

DOE Green Energy (OSTI)

This paper describes wind turbine flow fields that can cause adverse aerodynamic loading and can impact active aerodynamic control methodologies currently contemplated for wind turbine applications.

Schreck, S.; Robinson, M.

2007-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

CFD analysis of rotating two-bladed flatback wind turbine rotor.  

DOE Green Energy (OSTI)

The effects of modifying the inboard portion of the NREL Phase VI rotor using a thickened, flatback version of the S809 design airfoil are studied using a three-dimensional Reynolds-averaged Navier-Stokes method. A motivation for using such a thicker airfoil design coupled with a blunt trailing edge is to alleviate structural constraints while reducing blade weight and maintaining the power performance of the rotor. The calculated results for the baseline Phase VI rotor are benchmarked against wind tunnel results obtained at 10, 7, and 5 meters per second. The calculated results for the modified rotor are compared against those of the baseline rotor. The results of this study demonstrate that a thick, flatback blade profile is viable as a bridge to connect structural requirements with aerodynamic performance in designing future wind turbine rotors.

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

2008-04-01T23:59:59.000Z

102

Distrubance Tracking and Blade Load Control of Wind Turbines in Variable-Speed Operation: Preprint  

DOE Green Energy (OSTI)

A composite state-space controller was developed for a multi-objective problem in the variable-speed operation of wind turbines. Disturbance Tracking Control theory was applied to the design of a torque controller to optimize energy capture under the influence of persistent wind disturbances. A limitation in the theory for common multi-state models is described, which led to the design of a complementary pitch controller. The goal of the independent blade pitch design was to minimize blade root fatigue loads. Simulation results indicate an 11% reduction in fatigue damage using the proposed controllers, compared to a conventional torque-only design. Meanwhile, energy capture is almost identical, partly because of nonlinear effects.

Stol, K. A.

2003-01-01T23:59:59.000Z

103

Changes related to "Tianjin Dongqi Wind Turbine Blade Engineering...  

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104

Changes related to "Wuxi Bamboo Wind Turbine Blade Technology...  

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105

Tianjin Dongqi Wind Turbine Blade Engineering Co Ltd | Open Energy...  

Open Energy Info (EERE)

Policies International Clean Energy Analysis Low Emission Development Strategies Oil & Gas Smart Grid Solar U.S. OpenLabs Utilities Water Wind Page Actions View form View source...

106

WindPACT Turbine Design Scaling Studies Technical Area 1-Composite Blades for 80- to 120-Meter Rotor  

SciTech Connect

The United States Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL) implemented the Wind Partnership for Advanced Component Technologies (WindPACT) program. As part of the WindPACT program, Global Energy Concepts, LLC (GEC), was awarded contract number YAM-0-30203-01 to examine Technical Area 1-Blade Scaling, Technical Area 2-Turbine Rotor and Blade Logistics, and Technical Area 3-Self-Erecting Towers. This report documents the results of GEC's Technical Area 1-Blade Scaling. The primary objectives of the Blade-Scaling Study are to assess the scaling of current materials and manufacturing technologies for blades of 40 to 60 meters in length, and to develop scaling curves of estimated cost and mass for rotor blades in that size range.

Griffin, D.A.

2001-04-30T23:59:59.000Z

107

Necessity and Requirements of a Collaborative Effort to Develop a Large Wind Turbine Blade Test Facility in North America  

DOE Green Energy (OSTI)

The wind power industry in North America has an immediate need for larger blade test facilities to ensure the survival of the industry. Blade testing is necessary to meet certification and investor requirements and is critical to achieving the reliability and blade life needed for the wind turbine industry to succeed. The U.S. Department of Energy's (DOE's) Wind Program is exploring options for collaborating with government, private, or academic entities in a partnership to build larger blade test facilities in North America capable of testing blades up to at least 70 m in length. The National Renewable Energy Laboratory (NREL) prepared this report for DOE to describe the immediate need to pursue larger blade test facilities in North America, categorize the numerous prospective partners for a North American collaboration, and document the requirements for a North American test facility.

Cotrell, J.; Musial, W.; Hughes, S.

2006-05-01T23:59:59.000Z

108

Application of a wireless sensor node to health monitoring of operational wind turbine blades  

Science Conference Proceedings (OSTI)

Structural health monitoring (SHM) is a developing field of research with a variety of applications including civil structures, industrial equipment, and energy infrastructure. An SHM system requires an integrated process of sensing, data interrogation and statistical assessment. The first and most important stage of any SHM system is the sensing system, which is traditionally composed of transducers and data acquisition hardware. However, such hardware is often heavy, bulky, and difficult to install in situ. Furthermore, physical access to the structure being monitored may be limited or restricted, as is the case for rotating wind turbine blades or unmanned aerial vehicles, requiring wireless transmission of sensor readings. This study applies a previously developed compact wireless sensor node to structural health monitoring of rotating small-scale wind turbine blades. The compact sensor node collects low-frequency structural vibration measurements to estimate natural frequencies and operational deflection shapes. The sensor node also has the capability to perform high-frequency impedance measurements to detect changes in local material properties or other physical characteristics. Operational measurements were collected using the wireless sensing system for both healthy and damaged blade conditions. Damage sensitive features were extracted from the collected data, and those features were used to classify the structural condition as healthy or damaged.

Taylor, Stuart G [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Farrar, Charles R [Los Alamos National Laboratory; Todd, Michael D [UCSD

2009-01-01T23:59:59.000Z

109

Comparison of strength and load-based methods for testing wind turbine blades  

DOE Green Energy (OSTI)

The purpose of this paper is to compare two methods of blade test loading and show how they are applied in an actual blade test. Strength and load-based methods were examined to determine the test load for an Atlantic Orient Corporation (AOC) 15/50 wind turbine blade for fatigue and static testing. Fatigue load-based analysis was performed using measured field test loads extrapolated for extreme rare events and scaled to thirty-year spectra. An accelerated constant amplitude fatigue test that gives equivalent damage at critical locations was developed using Miner`s Rule and the material S-N curves. Test load factors were applied to adjust the test loads for uncertainties, and differences between the test and operating environment. Similar analyses were carried, out for the strength-based fatigue test using the strength of the blade and the material properties to determine the load level and number of constant amplitude cycles to failure. Static tests were also developed using load and strength criteria. The resulting test loads were compared and contrasted. The analysis shows that, for the AOC 15/50 blade, the strength-based test loads are higher than any of the static load-based cases considered but were exceeded in the fatigue analysis for a severe hot/wet environment.

Musial, W.D.; Clark, M.E.; Egging, N. [and others

1996-11-01T23:59:59.000Z

110

Base excitation testing system using spring elements to pivotally mount wind turbine blades  

DOE Patents (OSTI)

A system (1100) for fatigue testing wind turbine blades (1102) through forced or resonant excitation of the base (1104) of a blade (1102). The system (1100) includes a test stand (1112) and a restoring spring assembly (1120) mounted on the test stand (1112). The restoring spring assembly (1120) includes a primary spring element (1124) that extends outward from the test stand (1112) to a blade mounting plate (1130) configured to receive a base (1104) of blade (1102). During fatigue testing, a supported base (1104) of a blad (1102) may be pivotally mounted to the test stand (1112) via the restoring spring assembly (1120). The system (1100) may include an excitation input assembly (1140) that is interconnected with the blade mouting plate (1130) to selectively apply flapwise, edgewise, and/or pitch excitation forces. The restoring spring assemply (1120) may include at least one tuning spring member (1127) positioned adjacent to the primary spring element (1124) used to tune the spring constant or stiffness of the primary spring element (1124) in one of the excitation directions.

Cotrell, Jason; Hughes, Scott; Butterfield, Sandy; Lambert, Scott

2013-12-10T23:59:59.000Z

111

A wind turbine blade is ready to be lifted into place at the Windy Point Wind Farm in the Columbia River Gorge. Photo: C. Bruce Forster  

E-Print Network (OSTI)

A wind turbine blade is ready to be lifted into place at the Windy Point Wind Farm in the Columbia with juvenile bypass systems to keep the smolts out of the turbines. But given the gravity of the [salmon 1956 12 MW Chief Joseph Columbia, WA 1958 2,458 MW Cougar McKenzie, OR 1963 25 MW Detroit Santiam

112

An Experimental Investigation on the Control of Tip Vortices from Wind Turbine Blade.  

E-Print Network (OSTI)

??Wind turbine dynamics, wake effects and environmental impacts have been identified the most significant research topics needed for wind resource characterization and wind power generation. (more)

Ning, Zhe

2013-01-01T23:59:59.000Z

113

Effect of Load Phase Angle on Wind Turbine Blade Fatigue Damage: Preprint  

DOE Green Energy (OSTI)

This paper examines the importance of phase angle variations with respect to fatigue damage. The operating loads on a generic conventional three-bladed upwind 1.5-MW wind turbine blade were analyzed over a range of operating conditions, and an aggregate probability distribution for the actual phase angles between the in-plane (lead-lag) and out-of-plane (flap) loads was determined. Using a finite element model of a generic blade and Miner's Rule, the accumulated theoretical damage (based on axial strains) resulting from a fatigue test with variable phase angles was compared to the damage resulting from a fatigue test with a constant phase angle. The nodal damage distribution at specific blade cross-sections are compared for the constant and variable phase angle cases. The sequence effects of various phase angle progressions were also considered. For this analysis, the finite element results were processed using the nonlinear Marco-Starkey damage accumulation model. Each phase angle sequence was constrained to have the same overall phase angle distribution and the same total number of cycles but the order in which the phase angles were applied was varied.

White, D. L.; Musial, W. D.

2003-11-01T23:59:59.000Z

114

Task 4.1 Intelligent Manufacturing of Hybrid Carbon-Glass Fiber-Reinforced Composite Wind Turbine Blades  

DOE Green Energy (OSTI)

EXECUTIVE SUMARY In this subtask, the manufacturability of hybrid carbon-glass fiber-reinforced composite wind turbine blades using Vacuum-Assisted Resin Transfer Molding (VARTM) was investigated. The objective of this investigation was to study the VARTM process and its parameters to manufacture cost-effective wind turbine blades with no defects (mainly eliminate dry spots and reduce manufacturing time). A 2.5-dimensional model and a 3-dimensional model were developed to simulate mold filling and part curing under different conditions. These conditions included isothermal and non-isothermal filling, curing of the part during and after filling, and placement of injection gates at different locations. Results from this investigation reveal that the process can be simulated and also that manufacturing parameters can be optimized to eliminate dry spot formation and reduce the manufacturing time. Using computer-based models is a cost-effective way to simulate manufacturing of wind turbine blades. The approach taken herein allows the design of the wind blade manufacturing processes without physically running trial-and-error experiments that are expensive and time-consuming; especially for larger blades needed for more demanding environmental conditions. This will benefit the wind energy industry by reducing initial design and manufacturing costs which can later be passed down to consumers and consequently make the wind energy industry more competitive.

Janet M Twomey, PhD

2010-04-30T23:59:59.000Z

115

An Innovative Technique for Evaluating the Integrity and Durability of Wind Turbine Blade Composites - Final Project Report  

DOE Green Energy (OSTI)

To build increasingly larger, lightweight, and robust wind turbine blades for improved power output and cost efficiency, durability of the blade, largely resulting from its structural composites selection and aerodynamic shape design, is of paramount concern. The safe/reliable operation of structural components depends critically on the selection of materials that are resistant to damage and failure in the expected service environment. An effective surveillance program is also necessary to monitor the degradation of the materials in the course of service. Composite materials having high specific strength/stiffness are desirable for the construction of wind turbines. However, most high-strength materials tend to exhibit low fracture toughness. That is why the fracture toughness of the composite materials under consideration for the manufacture of the next generation of wind turbines deserves special attention. In order to achieve the above we have proposed to develop an innovative technology, based on spiral notch torsion test (SNTT) methodology, to effectively investigate the material performance of turbine blade composites. SNTT approach was successfully demonstrated and extended to both epoxy and glass fiber composite materials for wind turbine blades during the performance period. In addition to typical Mode I failure mechanism, the mixed-mode failure mechanism induced by the wind turbine service environments and/or the material mismatch of the composite materials was also effectively investigated using SNTT approach. The SNTT results indicate that the proposed protocol not only provides significant advance in understanding the composite failure mechanism, but also can be readily utilized to assist the development of new turbine blade composites.

Wang, Jy-An John [ORNL; Ren, Fei [ORNL; Tan, Ting [ORNL; Mandell, John [Montana State University; Agastra, Pancasatya [Montana State University

2011-11-01T23:59:59.000Z

116

Analysis of SNL/MSU/DOE fatigue database trends for wind turbine blade materials.  

DOE Green Energy (OSTI)

This report presents an analysis of trends in fatigue results from the Montana State University program on the fatigue of composite materials for wind turbine blades for the period 2005-2009. Test data can be found in the SNL/MSU/DOE Fatigue of Composite Materials Database which is updated annually. This is the fifth report in this series, which summarizes progress of the overall program since its inception in 1989. The primary thrust of this program has been research and testing of a broad range of structural laminate materials of interest to blade structures. The report is focused on current types of infused and prepreg blade materials, either processed in-house or by industry partners. Trends in static and fatigue performance are analyzed for a range of materials, geometries and loading conditions. Materials include: sixteen resins of three general types, five epoxy based paste adhesives, fifteen reinforcing fabrics including three fiber types, three prepregs, many laminate lay-ups and process variations. Significant differences in static and fatigue performance and delamination resistance are quantified for particular materials and process conditions. When blades do fail, the likely cause is fatigue in the structural detail areas or at major flaws. The program is focused strongly on these issues in addition to standard laminates. Structural detail tests allow evaluation of various blade materials options in the context of more realistic representations of blade structure than do the standard test methods. Types of structural details addressed in this report include ply drops used in thickness tapering, and adhesive joints, each tested over a range of fatigue loading conditions. Ply drop studies were in two areas: (1) a combined experimental and finite element study of basic ply drop delamination parameters for glass and carbon prepreg laminates, and (2) the development of a complex structured resin-infused coupon including ply drops, for comparison studies of various resins, fabrics and pry drop thicknesses. Adhesive joint tests using typical blade adhesives included both generic testing of materials parameters using a notched-lap-shear test geometry developed in this study, and also a series of simulated blade web joint geometries fabricated by an industry partner.

Mandell, John F. (Montana State University, Bozeman, MT); Ashwill, Thomas D.; Wilson, Timothy J. (Montana State University, Bozeman, MT); Sears, Aaron T. (Montana State University, Bozeman, MT); Agastra, Pancasatya (Montana State University, Bozeman, MT); Laird, Daniel L.; Samborsky, Daniel D. (Montana State University, Bozeman, MT)

2010-12-01T23:59:59.000Z

117

Measured and predicted rotor performance for the SERI advanced wind turbine blades  

DOE Green Energy (OSTI)

Measured and predicted rotor performance for the SERI advanced wind turbine blades were compared to assess the accuracy of predictions and to identify the sources of error affecting both predictions and measurements. An awareness of these sources of error contributes to improved prediction and measurement methods that will ultimately benefit future rotor design efforts. Propeller/vane anemometers were found to underestimate the wind speed in turbulent environments such as the San Gorgonio Pass wind farm area. Using sonic or cup anemometers, good agreement was achieved between predicted and measured power output for wind speeds up to 8 m/sec. At higher wind speeds an optimistic predicted power output and the occurrence of peak power at wind speeds lower than measurements resulted from the omission of turbulence and yaw error. In addition, accurate two-dimensional (2-D) airfoil data prior to stall and a post stall airfoil data synthesization method that reflects three-dimensional (3-D) effects were found to be essential for accurate performance prediction. 11 refs.

Tangler, J.; Smith, B.; Kelley, N.; Jager, D.

1992-02-01T23:59:59.000Z

118

Examination, evaluation, and repair of laminated wood blades after service on the Mod-OA wind turbine  

SciTech Connect

As a result of about 7 years of effort at the NASA Lewis Research Center, laminated wood blades were designed, fabricated, and installed on a 200-kW wind turbine (Mod-OA). The machine uses a two-blade rotor with a diameter of 38.1 m (125 ft). Each blade weighs less than 1361 kg (3000 lb). After operating in the field, two blade sets were returned for inspection. One set had been in Hawaii for 17 months (7844 h of operation) and the other had been at Block Island, Rhode Island, for 26 months (22 months operating - 7564 h). The Hawaii set was returned because one of the studs that holds the blade to the hub had failed. This was found to be caused by a combination of improper installation and inadequate corrosion protection. No other problems were found. The broken stud (along with four others that were badly corroded) was replaced and the blades are now in storage. The Block Island set of blades was returned at the completion of the test program, but one blade was found to have developed a crack in the leading edge along the entire span. This crack was found to be the result of a manufacturing process problem but was not structurally critical. When a load-deflection test was conducted on the cracked blade, the response was identical to that measured before installation. In general, the laminate quality of both blade sets was excellent. No significant internal delamination or structural defects were found in any blade. The stud bonding process requires close tolerance control and adequate corrosion protection, but studs can be removed and replaced without major problems. Moisture content stabilization does not appear to be a problem, and laminated wood blades are satisfactory for long-term operation on Mod-OA wind turbines.

Faddoul, J.R.

1983-01-01T23:59:59.000Z

119

An Innovative Technique for Evaluating the Integrity and Durability of Wind Turbine Blade Composites  

SciTech Connect

Wind turbine blades are subjected to complex multiaxial stress states during operation. A review of the literature suggests that mixed mode fracture toughness can be significantly less than that of the tensile opening mode (Mode I), implying that fracture failure can occur at a much lower load capacity if the structure is subject to mixed-mode loading. Thus, it will be necessary to identify the mechanisms that might lead to failure in blade materials under mixed-mode loading conditions. Meanwhile, wind turbine blades are typically fabricated from fiber reinforced polymeric materials, e.g. fiber glass composites. Due to the large degree of anisotropy in mechanical properties that is usually associated with laminates, the fracture behavior of these composite materials is likely to be strongly dependent on the loading conditions. This may further strengthen the need to study the effect of mixed-mode loading on the integrity and durability of the wind turbine blade composites. To quantify the fracture behavior of composite structures under mixed mode loading conditions, particularly under combined Mode I (flexural or normal tensile stress) and Mode III (torsional shear stress) loading, a new testing technique is proposed based on the spiral notch torsion test (SNTT). As a 2002 R&D 100 Award winner, SNTT is a novel fracture testing technology. SNTT has many advantages over conventional fracture toughness methods and has been used to determine fracture toughness values on a wide spectrum of materials. The current project is the first attempt to utilize SNTT on polymeric and polymer-based composite materials. It is expected that mixed-mode failure mechanisms of wind turbine blades induced by typical in-service loading conditions, such as delamination, matrix cracking, fiber pull-out and fracture, can be effectively and economically investigated by using this methodology. This project consists of two phases. The Phase I (FY2010) effort includes (1) preparation of testing material and testing equipment set-up, including calibration of associated instruments/sensors, (2) development of design protocols for the proposed SNTT samples for both polymer and composite materials, such as sample geometries and fabrication techniques, (3) manufacture of SNTT samples, and (4) fracture toughness testing using the SNTT method. The major milestone achieved in Phase I is the understanding of fracture behaviors of polymeric matrix materials from testing numerous epoxy SNTT samples. Totals of 30 epoxy SNTT samples were fabricated from two types of epoxy materials provided by our industrial partners Gougeon Brothers, Inc. and Molded Fiber Glass Companies. These samples were tested with SNTT in three groups: (1) fracture due to monotonic loading, (2) fracture due to fatigue cyclic loading, and (3) monotonic loading applied to fatigue-precracked samples. Brittle fractures were observed on all tested samples, implying linear elastic fracture mechanics analysis can be effectively used to estimate the fracture toughness of these materials with confidence. Appropriate fatigue precracking protocols were established to achieve controllable crack growth using the SNTT approach under pure torsion loading. These fatigue protocols provide the significant insights of the mechanical behavior of epoxy polymeric materials and their associated rate-dependent characteristics. Effects of mixed-mode loading on the fracture behavior of epoxy materials was studied. It was found that all epoxy samples failed in brittle tensile failure mode; the fracture surfaces always follow a 45o spiral plane that corresponded to Mode I tensile failure, even when the initial pitch angle of the machined spiral grooves was not at 45o. In addition, general observation from the fatigue experiments implied that loading rate played an important role determining the fracture behavior of epoxy materials, such that a higher loading rate resulted in a shorter fatigue life. A detailed study of loading rate effect will be continued in the Phase II. On the other hand, analytical finite element ana

Wang, Jy-An John [ORNL; Ren, Fei [ORNL

2010-09-01T23:59:59.000Z

120

Wind Turbines  

Energy.gov (U.S. Department of Energy (DOE))

Although all wind turbines operate on similar principles, several varieties are in use today. These include horizontal axis turbines and vertical axis turbines.

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

WindPACT Turbine Design Scaling Studies Technical Area 2: Turbine, Rotor, and Blade Logistics; March 27, 2000 to December 31, 2000  

NLE Websites -- All DOE Office Websites (Extended Search)

1 * NREL/SR-500-29439 1 * NREL/SR-500-29439 Kevin Smith Global Energy Concepts LLC Kirkland, Washington WindPACT Turbine Design Scaling Studies Technical Area 2: Turbine, Rotor, and Blade Logistics March 27, 2000 to December 31, 2000 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute * * * * Battelle * * * * Bechtel Contract No. DE-AC36-99-GO10337 June 2001 * NREL/SR-500-29439 WindPACT Turbine Design Scaling Studies Technical Area 2: Turbine, Rotor, and Blade Logistics March 27, 2000 to December 31, 2000 Kevin Smith Global Energy Concepts LLC Kirkland, Washington NREL Technical Monitor: Alan Laxson Prepared under Subcontract No. YAM-0-30203-01 National Renewable Energy Laboratory

122

Effect of Blade Torsion on Modeling Results for the Small Wind Research Turbine (SWRT): Preprint  

DOE Green Energy (OSTI)

This paper summarizes modeling results from both the FAST and ADAMS aeroelastic simulators characterizing small wind turbine loads and dynamic behavior.

Corbus, D.; Hansen, A. C.; Minnema, J.

2006-01-01T23:59:59.000Z

123

Airfoils for wind turbine  

DOE Patents (OSTI)

Airfoils for the blade of a wind turbine wherein each airfoil is characterized by a thickness in a range from 16%-24% and a maximum lift coefficient designed to be largely insensitive to roughness effects. The airfoils include a family of airfoils for a blade 15 to 25 meters in length, a family of airfoils for a blade 1 to 5 meters in length, and a family of airfoils for a blade 5 to 10 meters in length.

Tangler, James L. (Boulder, CO); Somers, Dan M. (State College, PA)

1996-01-01T23:59:59.000Z

124

Airfoils for wind turbine  

DOE Patents (OSTI)

Airfoils are disclosed for the blade of a wind turbine wherein each airfoil is characterized by a thickness in a range from 16%-24% and a maximum lift coefficient designed to be largely insensitive to roughness effects. The airfoils include a family of airfoils for a blade 15 to 25 meters in length, a family of airfoils for a blade 1 to 5 meters in length, and a family of airfoils for a blade 5 to 10 meters in length. 10 figs.

Tangler, J.L.; Somers, D.M.

1996-10-08T23:59:59.000Z

125

WindPACT Turbine Design Scaling Studies Technical Area 1ŒComposite Blades for 80- to 120-Meter Rotor  

NLE Websites -- All DOE Office Websites (Extended Search)

1 * NREL/SR-500-29492 1 * NREL/SR-500-29492 Dayton A. Griffin Global Energy Concepts Kirkland, Washington WindPACT Turbine Design Scaling Studies Technical Area 1-Composite Blades for 80- to 120-Meter Rotor March 21, 2000 - March 15, 2001 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute * * * * Battelle * * * * Bechtel Contract No. DE-AC36-99-GO10337 April 2001 * NREL/SR-500-29492 WindPACT Turbine Design Scaling Studies Technical Area 1-Composite Blades for 80- to 120-Meter Rotor March 21, 2000 - March 15, 2001 Dayton A. Griffin Global Energy Concepts Kirkland, Washington NREL Technical Monitor: Alan Laxson Prepared under Subcontract No. YAM-0-30203-01 National Renewable Energy Laboratory

126

Low-Order Modelling of Blade-Induced Turbulence for RANS Actuator Disk Computations of Wind and Tidal Turbines  

E-Print Network (OSTI)

Modelling of turbine blade-induced turbulence (BIT) is discussed within the framework of three-dimensional Reynolds-averaged Navier-Stokes (RANS) actuator disk computations. We first propose a generic (baseline) BIT model, which is applied only to the actuator disk surface, does not include any model coefficients (other than those used in the original RANS turbulence model) and is expected to be valid in the limiting case where BIT is fully isotropic and in energy equilibrium. The baseline model is then combined with correction functions applied to the region behind the disk to account for the effect of rotor tip vortices causing a mismatch of Reynolds shear stress between short- and long-time averaged flow fields. Results are compared with wake measurements of a two-bladed wind turbine model of Medici and Alfredsson [Wind Energy, Vol. 9, 2006, pp. 219-236] to demonstrate the capability of the new model.

Nishino, Takafumi

2012-01-01T23:59:59.000Z

127

Stress and Fracture Analysis of a Class of Bonded Joints in Wind Turbine Blades  

E-Print Network (OSTI)

A simplified model is proposed to investigate the stress fields and the strain energy release rate (SERR) associated with cracks in bonded joints in wind turbine blades. The proposed two-dimensional model consists of nonparallel upper and lower shells with adhesive between the shells at the tapered end. Nonlinear finite element analysis (FEA) is performed in a systematic parametric study of material and geo- metric properties. Two failure modes and their locations are predicted at different combinations of parameters: yielding at the outside end of the adhesive and interface cracking at the inside end of the bondline. Effect of the shell curvature on the stress fields is also considered. Based on the classic beam theory and the beam-on-elastic-foundation (BOEF) assumption, stress and displacement fields of the adhesively-bonded joint were determined by a new theoretical model to support the results from the numerical computation. The failure analysis is continued by studying the effects of manufacturing defects in the adhesive bond. Single and multiple voids are embedded to simulate air bubble trapped in the interface. The numerical and analytical studies are conducted to investigate SERR associated with the voids and results are provided to illustrate the effects of void position and void size.

Chen, Chang

2013-05-01T23:59:59.000Z

128

In-field use of laser Doppler vibrometer on a wind turbine blade  

DOE Green Energy (OSTI)

One of our primary goals was to determine how well a laser Doppler vibrometer (LDV) could measure the structural dynamic response of a wind turbine that was parked in the field. We performed a series of preliminary tests in the lab to determine the basic limitations of the LDV for this application. We then instrumented an installed parked horizontal axis wind turbine with accelerometers to determine the natural frequencies, damping, and mode shapes of the wind turbine and rotor as a baseline for the LDV and our other tests. We also wanted to determine if LDV modal information could be obtained from a naturally (wind) excited wind turbine. We compared concurrently obtained accelerometer and LDV data in an attempt to assess the quality of the LDV data. Our test results indicate the LDV can be successfully used in the field environment of an installed wind turbine, but with a few restrictions. We were successful in obtaining modal information from a naturally (wind) excited wind turbine in the field, but the data analysis requires a large number of averaged data sets to obtain reasonable results. An ultimate goal of this continuing project is to develop a technique that will monitor the health of a structure, detect damage, and hopefully predict an impending component failure.

Rumsey, M.; Hurtado, J.; Hansche, B. [and others

1998-12-31T23:59:59.000Z

129

Design of a self-regulating composite bearingless blade wind turbine. Final report, October 15, 1976-August 15, 1977  

DOE Green Energy (OSTI)

A study was undertaken to design a 40-ft diameter wind turbine employing the UTRC/ERDA Self-Regulating Composite Bearingless Rotor (CBR) concept. The CBR concept was developed at United Technologies for rotary wing applications and is now in use on Sikorsky helicopters. The concept was further developed for wind turbine applications at UTRC under an ERDA contract in 1975-76. Successful wind tunnel tests were conducted during that contract, which demonstrated the self-starting and self-regulating features. The latest contract was to design a 40-ft system in the 5 kW - 15 kW power range. This effort included performance tradeoff studies, stress analyses of the blade and tower structure, a stability investigation, and engineering drawings of the complete system. However an overall cost analysis was not performed in this study.

Spierings, P.A.M.; Cheney, M.C.

1978-01-01T23:59:59.000Z

130

Snubber Assembly for Turbine Blades - Energy Innovation Portal  

Wind Energy; Partners (27) Visual Patent Search; Success Stories; News; Events; Snubber Assembly for Turbine Blades United States Patent Application *** PATENT ...

131

COOLED SNUBBER STRUCTURE FOR TURBINE BLADES - Energy Innovation Portal  

Wind Energy; Partners (27) Visual Patent Search; Success Stories; News; Events; COOLED SNUBBER STRUCTURE FOR TURBINE BLADES United States Patent Application ...

132

Evaluation of the New B-REX Fatigue Testing System for Multi-Megawatt Wind Turbine Blades: Preprint  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory (NREL) recently developed a new hybrid fatigue testing system called the Blade Resonance Excitation (B-REX) test system. The new system uses 65% less energy to test large wind turbine blades in half the time of NREL's dual-axis forced-displacement test method with lower equipment and operating costs. The B-REX is a dual-axis test system that combines resonance excitation with forced hydraulic loading to reduce the total test time required while representing the operating strains on the critical inboard blade stations more accurately than a single-axis test system. The analysis and testing required to fully implement the B-REX was significant. To control unanticipated blade motion and vibrations caused by dynamic coupling between the flap, lead-lag, and torsional directions, we needed to incorporate additional test hardware and control software. We evaluated the B-REX test system under stable operating conditions using a combination of various sensors. We then compared our results with results from the same blade, tested previously using NREL's dual-axis forced-displacement test method. Experimental results indicate that strain levels produced by the B-REX system accurately replicated the forced-displacement method. This paper describes the challenges we encountered while developing the new blade fatigue test system and the experimental results that validate its accuracy.

White, D.; Musial, W.; Engberg, S.

2004-12-01T23:59:59.000Z

133

Snubber assembly for turbine blades  

DOE Patents (OSTI)

A snubber associated with a rotatable turbine blade in a turbine engine, the turbine blade including a pressure sidewall and a suction sidewall opposed from the pressure wall. The snubber assembly includes a first snubber structure associated with the pressure sidewall of the turbine blade, a second snubber structure associated with the suction sidewall of the turbine blade, and a support structure. The support structure extends through the blade and is rigidly coupled at a first end portion thereof to the first snubber structure and at a second end portion thereof to the second snubber structure. Centrifugal loads exerted by the first and second snubber structures caused by rotation thereof during operation of the engine are at least partially transferred to the support structure, such that centrifugal loads exerted on the pressure and suctions sidewalls of the turbine blade by the first and second snubber structures are reduced.

Marra, John J

2013-09-03T23:59:59.000Z

134

Lightning protection system for a wind turbine  

DOE Patents (OSTI)

In a wind turbine (104, 500, 704) having a plurality of blades (132, 404, 516, 744) and a blade rotor hub (120, 712), a lightning protection system (100, 504, 700) for conducting lightning strikes to any one of the blades and the region surrounding the blade hub along a path around the blade hub and critical components of the wind turbine, such as the generator (112, 716), gearbox (708) and main turbine bearings (176, 724).

Costin, Daniel P. (Chelsea, VT); Petter, Jeffrey K. (Williston, VT)

2008-05-27T23:59:59.000Z

135

Blade shape for a tropskien type of vertical-axis wind turbine  

SciTech Connect

The equations derived to define a troposkien (the shape a completely flexible cable assumes when it is spun at a constant angular velocity about a vertical axis to which its two ends are attached) are described. The implications of the solutions on the design of a vertical-axis wind turbine are discussed for cases where gravity is neglected.

Blackwell, B.F.; Reis, G.E.

1977-03-01T23:59:59.000Z

136

Sustainable Energy Solutions Task 4.1 Intelligent Manufacturing of Hybrid Carbon-Glass Fiber-Reinforced Composite Wind Turbine Blades  

SciTech Connect

EXECUTIVE SUMARY In this subtask, the manufacturability of hybrid carbon-glass fiber-reinforced composite wind turbine blades using Vacuum-Assisted Resin Transfer Molding (VARTM) was investigated. The objective of this investigation was to study the VARTM process and its parameters to manufacture cost-effective wind turbine blades with no defects (mainly eliminate dry spots and reduce manufacturing time). A 2.5-dimensional model and a 3-dimensional model were developed to simulate mold filling and part curing under different conditions. These conditions included isothermal and non-isothermal filling, curing of the part during and after filling, and placement of injection gates at different locations. Results from this investigation reveal that the process can be simulated and also that manufacturing parameters can be optimized to eliminate dry spot formation and reduce the manufacturing time. Using computer-based models is a cost-effective way to simulate manufacturing of wind turbine blades. The approach taken herein allows the design of the wind blade manufacturing processes without physically running trial-and-error experiments that are expensive and time-consuming; especially for larger blades needed for more demanding environmental conditions. This will benefit the wind energy industry by reducing initial design and manufacturing costs which can later be passed down to consumers and consequently make the wind energy industry more competitive.

Janet M Twomey, PhD

2010-04-30T23:59:59.000Z

137

Comprehensive testing of Nedwind 12-Meter wind turbine blades at NREL  

DOE Green Energy (OSTI)

This paper describes the structural testing of two NedWind 25 12-m blades at the National Renewable Energy Laboratory (NREL). The tests were conducted under the Standards, Measurement and Testing (SMT) Program in conjunction with tests conducted by four European laboratories to develop a common database of blade testing methods. All of the laboratories tested duplicate copies of blades taken from series production. Blade properties, including weight, center of gravity, natural frequencies, stiffness, and damping, were determined. Static load tests were performed at 110% of the extreme design load for strain verification. NREL performed single-axis and two-axis fatigue tests using business-as-usual testing practices. The single-axis test combined equivalent life loading for the edge and flap spectra into a single resultant load. The two-axis test applied the edge and flap components independently at a phase angle of 90{degree}. Damage areas were observed at (1) the trailing edge, which cracked near the maximum chord; (2) between the steel root collar and the composite, where circumferential cracking was noted; and (3) along the top of the spar between the 2,500-mm and 4,200-mm stations, where a notable increase in acoustic emissions was detected. NREL observed that the onset of damage occurred earlier in the single-axis test.

Larwood, S.; Musial, W.

2000-03-13T23:59:59.000Z

138

LIDAR Wind Speed Measurement Analysis and Feed-Forward Blade Pitch Control for Load Mitigation in Wind Turbines: January 2010--January 2011  

SciTech Connect

This report examines the accuracy of measurements that rely on Doppler LIDAR systems to determine their applicability to wind turbine feed-forward control systems and discusses feed-forward control system designs that use preview wind measurements. Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feed-forward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. The first half of this report examines the accuracy of different measurement scenarios that rely on coherent continuous-wave or pulsed Doppler LIDAR systems to determine their applicability to feed-forward control. In particular, the impacts of measurement range and angular offset from the wind direction are studied for various wind conditions. A realistic case involving a scanning LIDAR unit mounted in the spinner of a wind turbine is studied in depth with emphasis on choices for scan radius and preview distance. The effects of turbulence parameters on measurement accuracy are studied as well. Continuous-wave and pulsed LIDAR models based on typical commercially available units were used in the studies present in this report. The second half of this report discusses feed-forward control system designs that use preview wind measurements. Combined feedback/feed-forward blade pitch control is compared to industry standard feedback control when simulated in realistic turbulent above-rated winds. The feed-forward controllers are designed to reduce fatigue loads, increasing turbine lifetime and therefore reducing the cost of energy. Three feed-forward designs are studied: non-causal series expansion, Preview Control, and optimized FIR filter. The input to the feed-forward controller is a measurement of incoming wind speeds that could be provided by LIDAR. Non-causal series expansion and Preview Control methods reduce blade root loads but increase tower bending in simulation results. The optimized FIR filter reduces loads overall, keeps pitch rates low, and maintains rotor speed regulation and power capture, while using imperfect wind measurements provided by the spinning continuous-wave LIDAR model.

Dunne, F.; Simley, E.; Pao, L.Y.

2011-10-01T23:59:59.000Z

139

Wind Turbines and Health  

E-Print Network (OSTI)

Wind power has been gaining prominence as a viable sustainable alternative to other forms of energy production. Studies have found that there is increasing population demand for green energy 1,2. In Australia, this has been encouraged by the introduction of the Renewable Energy (Electricity) Act in 2000 and the Renewable Energy Target Scheme in 2009. As with any new technology, wind turbines are not without controversy. Those who oppose the development of wind farms contend that wind turbines can adversely impact the health of individuals living in close proximity. Do wind turbines impact on health? Concerns regarding the adverse health impacts of wind turbines focus on infrasound noise, electromagnetic interference, shadow flicker and blade glint produced

unknown authors

2010-01-01T23:59:59.000Z

140

Wind Turbines and Health  

E-Print Network (OSTI)

Wind power has been gaining prominence as a viable sustainable alternative to other forms of energy production. Studies have found that there is increasing population demand for green energy1,2. In Australia, this has been encouraged by the introduction of the Renewable Energy (Electricity) Act in 2000 and the Renewable Energy Target Scheme in 2009. As with any new technology, wind turbines are not without controversy. Those who oppose the development of wind farms contend that wind turbines can adversely impact the health of individuals living in close proximity. Do wind turbines impact on health? Concerns regarding the adverse health impacts of wind turbines focus on infrasound noise, electromagnetic interference, shadow flicker and blade glint produced

unknown authors

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Wind turbine spoiler  

DOE Patents (OSTI)

An aerodynamic spoiler system for a vertical axis wind turbine includes spoilers on the blades initially stored near the rotor axis to minimize drag. A solenoid latch adjacent the central support tower releases the spoilers and centrifugal force causes the spoilers to move up the turbine blades away from the rotor axis, thereby producing a braking effect and actual slowing of the associated wind turbine, if desired. The spoiler system can also be used as an infinitely variable power control by regulated movement of the spoilers on the blades over the range between the undeployed and fully deployed positions. This is done by the use of a suitable powered reel and cable located at the rotor tower to move the spoilers.

Sullivan, William N. (Albuquerque, NM)

1985-01-01T23:59:59.000Z

142

Multiple piece turbine blade  

Science Conference Proceedings (OSTI)

A turbine rotor blade with a spar and shell construction, the spar including an internal cooling supply channel extending from an inlet end on a root section and ending near the tip end, and a plurality of external cooling channels formed on both side of the spar, where a middle external cooling channel is connected to the internal cooling supply channels through a row of holes located at a middle section of the channels. The spar and the shell are held together by hooks that define serpentine flow passages for the cooling air and include an upper serpentine flow circuit and a lower serpentine flow circuit. the serpentine flow circuits all discharge into a leading edge passage or a trailing edge passage.

Kimmel, Keith D (Jupiter, FL)

2012-05-29T23:59:59.000Z

143

Turbine blade cooling  

DOE Patents (OSTI)

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

Staub, Fred Wolf (Schenectady, NY); Willett, Fred Thomas (Niskayuna, NY)

1999-07-20T23:59:59.000Z

144

Turbine blade cooling  

DOE Patents (OSTI)

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

Staub, Fred Wolf (Schenectady, NY); Willett, Fred Thomas (Niskayuna, NY)

2000-01-01T23:59:59.000Z

145

Turbine blade cooling  

DOE Patents (OSTI)

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number. 13 figs.

Staub, F.W.; Willett, F.T.

1999-07-20T23:59:59.000Z

146

Turbine Blade Shape Favorable for Fish Survival  

Science Conference Proceedings (OSTI)

Various mechanisms associated with turbine design and operation injure fish passing through hydro turbines. Pilot-scale tests with various fish species and sizes showed that most turbine passage injury and mortality are caused by blade strike. Leading edge blade strike is particularly important for turbines with numerous blades. Very little information and data are available on the mechanics of fish struck by turbine blades and the resulting injury and mortality rates. Determining what leading edge blade...

2008-05-29T23:59:59.000Z

147

Turbine blade tip gap reduction system  

DOE Patents (OSTI)

A turbine blade sealing system for reducing a gap between a tip of a turbine blade and a stationary shroud of a turbine engine. The sealing system includes a plurality of flexible seal strips extending from a pressure side of a turbine blade generally orthogonal to the turbine blade. During operation of the turbine engine, the flexible seal strips flex radially outward extending towards the stationary shroud of the turbine engine, thereby reducing the leakage of air past the turbine blades and increasing the efficiency of the turbine engine.

Diakunchak, Ihor S.

2012-09-11T23:59:59.000Z

148

Wind turbine ring/shroud drive system - Energy Innovation Portal  

A wind turbine capable of driving multiple electric generators having a ring or shroud structure for reducing blade root bending moments, hub loads, blade fastener ...

149

The Economic Optimization of Wind Turbine Design .  

E-Print Network (OSTI)

??This thesis studies the optimization of a variable speed, three blade, horizontal-axis wind turbine. The design parameters considered are the rotor diameter, hub height and (more)

Schmidt, Michael Frank

2007-01-01T23:59:59.000Z

150

A comparison of spanwise aerodynamic loads estimated from measured bending moments versus direct pressure measurements on horizontal axis wind turbine blades  

DOE Green Energy (OSTI)

Two methods can be used to determine aerodynamic loads on a rotating wind turbine blade. The first is to make direct pressure measurements on the blade surface. This is a difficult process requiring costly pressure instrumentation. The second method uses measured flap bending moments in conjunction with analytical techniques to estimate airloads. This method, called ALEST, was originally developed for use on helicopter rotors and was modified for use on horizontal axis wind turbine blades. Estimating airloads using flap bending moments in much simpler and less costly because measurements can be made with conventional strain gages and equipment. This paper presents results of airload estimates obtained using both methods under a variety of operating conditions. Insights on the limitations and usefulness of the ALEST bending moment technique are also included. 10 refs., 6 figs.

Simms, D A; Butterfield, C P

1991-10-01T23:59:59.000Z

151

Wind Turbine Basics | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Wind Turbine Basics Wind Turbine Basics Wind Turbine Basics July 30, 2013 - 2:58pm Addthis Energy 101: Wind Turbines Basics This video explains the basics of how wind turbines operate to produce clean power from an abundant, renewable resource-the wind. Text Version Wind turbine assembly Although all wind turbines operate on similar principles, several varieties are in use today. These include horizontal axis turbines and vertical axis turbines. Horizontal Axis Turbines Horizontal axis turbines are the most common turbine configuration used today. They consist of a tall tower, atop which sits a fan-like rotor that faces into or away from the wind, a generator, a controller, and other components. Most horizontal axis turbines built today are two- or three-bladed. Horizontal axis turbines sit high atop towers to take advantage of the

152

NREL: Learning - Wind Energy Basics: How Wind Turbines Work  

NLE Websites -- All DOE Office Websites (Extended Search)

Wind Energy Basics: How Wind Turbines Work Wind Energy Basics: How Wind Turbines Work We have been harnessing the wind's energy for hundreds of years. From old Holland to farms in the United States, windmills have been used for pumping water or grinding grain. Today, the windmill's modern equivalent-a wind turbine-can use the wind's energy to generate electricity. Wind turbines, like windmills, are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more aboveground, they can take advantage of the faster and less turbulent wind. Turbines catch the wind's energy with their propeller-like blades. Usually, two or three blades are mounted on a shaft to form a rotor. A blade acts much like an airplane wing. When the wind blows, a pocket of low-pressure air forms on the downwind side of the blade. The low-pressure

153

A Kind of Innovative Design Methodology of Wind Turbine Blade Based on Natural Structure  

Science Conference Proceedings (OSTI)

Based on the mid axis pattern configuration, the topology adaption of the plant leaf vein is discussed in the first place., Secondly, combined with the blade principal stress field distribution cases, the adaptive design is applied in the blade structure ... Keywords: adaptation, blade, hybrid composites, mid axis pattern, stress field

Wangyu Liu; Jiaxing Gong; Xifeng Liu; Xin Zhang

2009-05-01T23:59:59.000Z

154

Implementation of a Two-Axis Servo-Hydraulic System for Full-Scale Fatigue Testing of Wind Turbine Blades  

DOE Green Energy (OSTI)

Recently, the blade fatigue testing capabilities at NREL were upgraded from single-axis to two-axis loading. To implement this, several practical challenges were addressed, as hardware complexity increased dramatically with two actuators applying the loads at right angles to each other. A custom bellcrank was designed and implemented to minimize the load angle errors and to prevent actuator side loading. The control system was upgraded to accept load and displacement feedback from two actuators. The inherent long strokes uniquely associated with wind turbine blade-tests required substantial real-time corrections for both the control and data systems. A custom data acquisition and control system was developed using a National Instruments LabVIEW platform that interfaces with proprietary servo-hydraulic software developed by MTS Corporation. Before testing, the program is run under quasi-static (slow speed) conditions and iterates to determine the correct operational control parameters for the controller, taking into consideration geometry, test speed, and phase angle errors between the two actuators. Comparisons are made between single-axis and two-axis test loads using actual test load data and load uncertainties are qualitatively described. To date, two fatigue tests have been completed and another is currently ongoing using NREL's two-axis capability.

Hughes, S. D.; Musial, W. D. [National Renewable Energy Lab., Golden, CO (US); Stensland, T. [Stensland Technologies (US)

1999-09-09T23:59:59.000Z

155

Energy Basics: Wind Turbines  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Wind Wind Turbines Wind Resources Wind Turbines...

156

Baoding Tianwei Wind Power Blade Co Ltd | Open Energy Information  

Open Energy Info (EERE)

Tianwei Wind Power Blade Co Ltd Tianwei Wind Power Blade Co Ltd Jump to: navigation, search Name Baoding Tianwei Wind Power Blade Co Ltd Place Hebei Province, China Sector Wind energy Product Wind turbine blade maker. References Baoding Tianwei Wind Power Blade Co Ltd[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Baoding Tianwei Wind Power Blade Co Ltd is a company located in Hebei Province, China . References ↑ "Baoding Tianwei Wind Power Blade Co Ltd" Retrieved from "http://en.openei.org/w/index.php?title=Baoding_Tianwei_Wind_Power_Blade_Co_Ltd&oldid=342529" Categories: Clean Energy Organizations Companies Organizations Stubs What links here Related changes Special pages

157

Method and apparatus for wind turbine braking  

DOE Patents (OSTI)

A method for braking a wind turbine including at least one rotor blade coupled to a rotor. The method includes selectively controlling an angle of pitch of the at least one rotor blade with respect to a wind direction based on a design parameter of a component of the wind turbine to facilitate reducing a force induced into the wind turbine component as a result of braking.

Barbu, Corneliu (Laguna Hills, CA); Teichmann, Ralph (Nishkayuna, NY); Avagliano, Aaron (Houston, TX); Kammer, Leonardo Cesar (Niskayuna, NY); Pierce, Kirk Gee (Simpsonville, SC); Pesetsky, David Samuel (Greenville, SC); Gauchel, Peter (Muenster, DE)

2009-02-10T23:59:59.000Z

158

Simulation of the Manufacturing of Non-Crimp Fabric-Reinforced Composite Wind Turbine Blades to Predict the Formation of Wave Defects  

SciTech Connect

NCFs (Non-Crimp Fabrics) are commonly used in the design of wind turbine blades and other complex systems due to their ability to conform to complex shapes without the wrinkling that is typically experienced with woven fabrics or prepreg tapes. In the current research, a form of vacuum assisted resin transfer molding known as SCRIMP registered is used to manufacture wind turbine blades. Often, during the compacting of the fabric layers by the vacuum pressure, several plies may bunch together out-of-plane and form wave defects. When the resin is infused, the areas beneath the waves become resin rich and can compromise the structural integrity of the blade. A reliable simulation tool is valuable to help predict where waves and other defects may appear as a result of the manufacturing process. Forming simulations often focus on the in-plane shearing and tensile behavior of fabrics and do not necessarily consider the bending stiffness of the fabrics, which is important to predict the formation of wrinkles and/or waves. This study incorporates experimentally determined in-plane shearing, tensile, and bending stiffness information of NCFs into a finite element model (ABAQUS/Explicit) of a 9-meter wind turbine blade to investigate the mechanical behaviors that can lead to the formation of waves as a result of the manufacturing process.

Fetfatsidis, K. A.; Sherwood, J. A. [Department of Mechanical Engineering, University of Massachusetts, Lowell One University Ave., Lowell, MA 01854 (United States)

2011-05-04T23:59:59.000Z

159

Analysis and test results for a two-bladed, passive cycle pitch, horizontal-axis wind turbine in free and controlled yaw  

SciTech Connect

This report surveys the analysis and tests performed at Washington University in St. Louis, Missouri, on a horizontal-axis, two-laded wind turbine with teeter hub. The introduction is a brief account of results obtained during the 5-year period ending December 1985. The wind tunnel model and the test turbine (7.6 m [25 ft.] in diameter) at Washington University`s Tyson Research Center had a 67{degree} delta-three angle of the teeter axis. The introduction explains why this configuration was selected and named the passive cycle pitch (PCP) wind turbine. Through the analysis was not limited to the PCP rotor, all tests, including those done from 1986 to 1994, wee conducted with the same teetered wind rotor. The blades are rather stiff and have only a small elastic coning angle and no precone.

Holenemser, K.H. [Washington Univ., St. Louis, MO (United States)

1995-10-01T23:59:59.000Z

160

Determining effects of turbine blades on fluid motion  

DOE Patents (OSTI)

Disclosed is a technique for simulating wind interaction with wind turbines. A turbine blade is divided into radial sections. The effect that each of these radial sections has on the velocities in Eulerian computational cells they overlap is determined. The effect is determined using Lagrangian techniques such that the calculations need not include wind components in the radial direction. A force on each radial section of turbine blade is determined. This force depends on the axial and azimuthal components of the fluid flow in the computational cell and the geometric properties of the turbine blade. The force on the turbine blade is fed back to effect the fluid flow in the computational cell for the next time step.

Linn, Rodman Ray (Los Alamos, NM); Koo, Eunmo (Los Alamos, NM)

2011-05-31T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Determining effects of turbine blades on fluid motion  

DOE Patents (OSTI)

Disclosed is a technique for simulating wind interaction with wind turbines. A turbine blade is divided into radial sections. The effect that each of these radial sections has on the velocities in Eulerian computational cells they overlap is determined. The effect is determined using Lagrangian techniques such that the calculations need not include wind components in the radial direction. A force on each radial section of turbine blade is determined. This force depends on the axial and azimuthal components of the fluid flow in the computational cell and the geometric properties of the turbine blade. The force on the turbine blade is fed back to effect the fluid flow in the computational cell for the next time step.

Linn, Rodman Ray (Los Alamos, NM); Koo, Eunmo (Los Alamos, NM)

2012-05-01T23:59:59.000Z

162

Wind Turbine Basics | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Turbine Basics Turbine Basics Wind Turbine Basics July 30, 2013 - 2:58pm Addthis Energy 101: Wind Turbines Basics This video explains the basics of how wind turbines operate to produce clean power from an abundant, renewable resource-the wind. Text Version Wind turbine assembly Although all wind turbines operate on similar principles, several varieties are in use today. These include horizontal axis turbines and vertical axis turbines. Horizontal Axis Turbines Horizontal axis turbines are the most common turbine configuration used today. They consist of a tall tower, atop which sits a fan-like rotor that faces into or away from the wind, a generator, a controller, and other components. Most horizontal axis turbines built today are two- or three-bladed. Horizontal axis turbines sit high atop towers to take advantage of the

163

Aircraft Gas Turbine Blade and Vane Repair  

Science Conference Proceedings (OSTI)

Gas turbine blades experience dimensional .... platinum applied in separate gas phase or electroplating ..... surfaces are natural consequences of fluoride.

164

Application of Resin Transfer Molding to the Manufacture of Wind Turbine Blade Substructures. Final Report  

DOE Green Energy (OSTI)

The U.S. has generally lacked the capability for an iterative process of detailed structural design, manufacturing, and testing at the full blade level to achieve specific structural performance, cost, and weight targets. This project examined the effects that different composites processing methods had on the performance of representative blade substructures. In addition, the results of the testing of these substructures was used to validate NuMAD, the design tool developed at Sandia National Laboratories.

Hedley, C. W.; Ritter, W. J.; Ashwill, T.

2001-07-26T23:59:59.000Z

165

LQG control of horizontal wind turbines for blades and tower loads alleviation  

E-Print Network (OSTI)

a profoundly irregular primary source, the wind. The characteristics of the wind energy source are important in different aspects regarding wind energy exploitation. The energy available in the wind varies with the cube, by a continuous essay to significantly improve all aspects of a wind energy conversion system. Many research works

166

How Does a Wind Turbine Work?  

Energy.gov (U.S. Department of Energy (DOE))

Wind turbines operate on a simple principle. The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to...

167

Turbine blade vibration dampening  

DOE Patents (OSTI)

The present turbine wheel assembly increases component life and turbine engine longevity. The combination of the strap and the opening combined with the preestablished area of the outer surface of the opening and the preestablished area of the outer circumferential surface of the strap and the friction between the strap and the opening increases the life and longevity of the turbine wheel assembly. Furthermore, the mass ``M`` or combined mass ``CM`` of the strap or straps and the centrifugal force assist in controlling vibrations and damping characteristics. 5 figs.

Cornelius, C.C.; Pytanowski, G.P.; Vendituoli, J.S.

1997-07-08T23:59:59.000Z

168

Turbine blade vibration dampening  

DOE Patents (OSTI)

The present turbine wheel assembly increases component life and turbine engine longevity. The combination of the strap and the opening combined with the preestablished area of the outer surface of the opening and the preestablished area of the outer circumferential surface of the strap and the friction between the strap and the opening increases the life and longevity of the turbine wheel assembly. Furthermore, the mass "M" or combined mass "CM" of the strap or straps and the centrifugal force assist in controlling vibrations and damping characteristics.

Cornelius, Charles C. (San Diego, CA); Pytanowski, Gregory P. (San Diego, CA); Vendituoli, Jonathan S. (San Diego, CA)

1997-07-08T23:59:59.000Z

169

Blade for a gas turbine  

SciTech Connect

A blade is provided for a gas turbine. The blade comprises a main body comprising a cooling fluid entrance channel; a cooling fluid collector in communication with the cooling fluid entrance channel; a plurality of side channels extending through an outer wall of the main body and communicating with the cooling fluid collector and a cooling fluid cavity; a cooling fluid exit channel communicating with the cooling fluid cavity; and a plurality of exit bores extending from the cooling fluid exit channel through the main body outer wall.

Liang, George (Palm City, FL)

2010-10-26T23:59:59.000Z

170

Nondestructive evaluation (NDE) of composite-to-metal bond interface of a wind turbine blade using an acousto-ultrasonic technique  

Science Conference Proceedings (OSTI)

An acousto-ultrasonic inspection technique was developed to evaluate the structural integrity of the epoxy bond interface between a metal insert and the fiber glass epoxy composite of a wind turbine blade. Data was generated manually as well as with a PC based data acquisition and display system. C-scan imaging using a portable ultrasonic scanning system provided an area mapping of the delamination or disbond due to fatigue testing and normal field operation conditions of the turbine blade. Comparison of the inspection data with a destructive visual examination of the bond interface to determine the extent of the disbond showed good agreement between the acousto-ultrasonic inspection data and the visual data.

Gieske, J.H.; Rumsey, M.A.

1996-12-31T23:59:59.000Z

171

Wind Turbine Post-Stall Airfoil Performance Characteristics Guidelines for Blade-Element Momentum Methods: Preprint  

DOE Green Energy (OSTI)

The objective of this study was to provide post-stall airfoil data input guidelines for the prediction of peak and post-peak rotor power when using blade-element momentum theory. A steady-state data set from the Unsteady Aerodynamic Experiment (UAE) rotor test was used to provide guidelines for the development of a global post-stall method for the prediction of post-stall 3-D airfoil characteristics to be used with 2-D airfoil data. Based on these UAE data, methods to emulate the 3-D aerodynamics in the post-stall region were explored. Also suggested are experimental tests needed to better understand the 3-D flow physics and to quantify needed theory or empirical factors for a global post-stall approach to support blade-element momentum methods.

Tangler, J. L.; Kocurek, J. D.

2004-10-01T23:59:59.000Z

172

Computer subroutine for estimating aerodynamic blade loads on Darrieus vertical axis wind turbines. [FORCE code  

DOE Green Energy (OSTI)

An important aspect of structural design of the Darrieus rotor is the determination of aerodynamic blade loads. This report describes a load generator which has been used at Sandia for quasi-static and dynamic rotor analyses. The generator is based on the single streamtube aerodynamic flow model and is constructed as a FORTRAN IV subroutine to facilitate its use in finite element structural models. Input and output characteristics of the subroutine are described and a complete listing is attached as an appendix.

Sullivan, W. N.; Leonard, T. M.

1980-11-01T23:59:59.000Z

173

Wind Turbine Generator System Acoustic Noise Test Report for the Gaia Wind 11-kW Wind Turbine  

DOE Green Energy (OSTI)

This report details the acoustic noise test conducted on the Gaia-Wind 11-kW wind turbine at the National Wind Technology Center. The test turbine is a two- bladed, downwind wind turbine with a rated power of 11 kW. The test turbine was tested in accordance with the International Electrotechnical Commission standard, IEC 61400-11 Ed 2.1 2006-11 Wind Turbine Generator Systems -- Part 11 Acoustic Noise Measurement Techniques.

Huskey, A.

2011-11-01T23:59:59.000Z

174

Wind turbine rotor aileron  

DOE Patents (OSTI)

A wind turbine has a rotor with at least one blade which has an aileron which is adjusted by an actuator. A hinge has two portions, one for mounting a stationary hinge arm to the blade, the other for coupling to the aileron actuator. Several types of hinges can be used, along with different actuators. The aileron is designed so that it has a constant chord with a number of identical sub-assemblies. The leading edge of the aileron has at least one curved portion so that the aileron does not vent over a certain range of angles, but vents if the position is outside the range. A cyclic actuator can be mounted to the aileron to adjust the position periodically. Generally, the aileron will be adjusted over a range related to the rotational position of the blade. A method for operating the cyclic assembly is also described.

Coleman, Clint (Warren, VT); Kurth, William T. (Warren, VT)

1994-06-14T23:59:59.000Z

175

Rotationally Augmented Flow Structures and Time Varying Loads on Turbine Blades: Preprint  

DOE Green Energy (OSTI)

To better understand wind turbine flow physics, time dependent blade surface pressure data were acquired from the NREL Unsteady Aerodynamics Experiment.

Schreck, S. J.

2007-01-01T23:59:59.000Z

176

Angel wing seals for blades of a gas turbine and methods for ...  

Wind Energy; Partners (27) Visual Patent Search; Success Stories; News; Events; Angel wing seals for blades of a gas turbine and methods for determining angel wing ...

177

Modern, three-blade wind turbines are 50 to 90 meters in diameter...  

NLE Websites -- All DOE Office Websites (Extended Search)

of trained and qualified workers to manufacture, construct, operate, and maintain the wind energy facilities. In addition, the nation will continue to need skilled scientists...

178

Turbine blade tip flow discouragers  

SciTech Connect

A turbine assembly comprises a plurality of rotating blade portions in a spaced relation with a stationery shroud. The rotating blade portions comprise a root section, a tip portion and an airfoil. The tip portion has a pressure side wall and a suction side wall. A number of flow discouragers are disposed on the blade tip portion. In one embodiment, the flow discouragers extend circumferentially from the pressure side wall to the suction side wall so as to be aligned generally parallel to the direction of rotation. In an alternative embodiment, the flow discouragers extend circumferentially from the pressure side wall to the suction side wall so as to be aligned at an angle in the range between about 0.degree. to about 60.degree. with respect to a reference axis aligned generally parallel to the direction of rotation. The flow discouragers increase the flow resistance and thus reduce the flow of hot gas flow leakage for a given pressure differential across the blade tip portion so as to improve overall turbine efficiency.

Bunker, Ronald Scott (Niskayuna, NY)

2000-01-01T23:59:59.000Z

179

Probabilistic analysis of turbine blade durability  

E-Print Network (OSTI)

The effect of variability on turbine blade durability was assessed for seven design/operating parameters in three blade designs. The parameters included gas path and cooling convective parameters, metal and coating thermal ...

Kountras, Apostolos, 1970-

2004-01-01T23:59:59.000Z

180

Study on mechanical properties of cork composites in a sandwich panel for wind turbine blade material  

E-Print Network (OSTI)

Wind energy has become one of the most promising energy sources due to its environmentally friendliness, unlimited amounts. To become competitive energy source among other sustainable and clean energy, such as solar cell, ...

Kim, Sungmin, Mech. E. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Evaluation of Turbine Blades Using Computed Tomography  

E-Print Network (OSTI)

Turbine blades are high value castings having complex internal geometry. Computed Tomography has been employed on Turbine blades for finding out defects and internal details. The wall thickness, rib thickness and radius of curvature are measured from the CT slices. The discontinuities including blockages of cooling passages in the cast material can be detected. 3D visualization of the turbine blade provides in extracting its internal features including inaccessible areas nondestructively, which is not possible through conventional NDE methods. The salient features for evaluation of turbine blades using Tomography are brought out.

C. Muralidhar; S. N. Lukose; M. P. Subramanian

2006-01-01T23:59:59.000Z

182

Help Wanted at Kansas Wind Blade Company | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Help Wanted at Kansas Wind Blade Company Help Wanted at Kansas Wind Blade Company Help Wanted at Kansas Wind Blade Company July 12, 2010 - 12:00pm Addthis Stephen Graff Former Writer & editor for Energy Empowers, EERE Last year, Israel Sanchez, a 31-year-old Newton, Kan., resident, was painting the blades of wind turbines for Enertech, Inc., a small-scale wind manufacturer. Now he's assembling the entire system. "They promoted me," says Sanchez, taking a quick break from the assembly line in the 10,000 square-foot plant in Newton. "It's a new field for me, but I'm excited because it's all new experiences every day." Sanchez is assembling Enertech's new wind models using an innovative blade design licensed from the National Renewable Energy Laboratory (NREL) in Golden, Colo., on its 40 kW turbines.

183

Help Wanted at Kansas Wind Blade Company | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Wanted at Kansas Wind Blade Company Wanted at Kansas Wind Blade Company Help Wanted at Kansas Wind Blade Company July 12, 2010 - 12:00pm Addthis Stephen Graff Former Writer & editor for Energy Empowers, EERE Last year, Israel Sanchez, a 31-year-old Newton, Kan., resident, was painting the blades of wind turbines for Enertech, Inc., a small-scale wind manufacturer. Now he's assembling the entire system. "They promoted me," says Sanchez, taking a quick break from the assembly line in the 10,000 square-foot plant in Newton. "It's a new field for me, but I'm excited because it's all new experiences every day." Sanchez is assembling Enertech's new wind models using an innovative blade design licensed from the National Renewable Energy Laboratory (NREL) in Golden, Colo., on its 40 kW turbines.

184

PPG and MAG Team Up for Turbine Blade Research | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

PPG and MAG Team Up for Turbine Blade Research PPG and MAG Team Up for Turbine Blade Research PPG and MAG Team Up for Turbine Blade Research May 14, 2010 - 12:39pm Addthis Lindsay Gsell For more than 15 years, PPG Industries has been supplying fiberglass to the wind turbine production industry. Now, with more than $700,000 in Recovery Act funds, PPG and partner MAG Industrial Automation Systems are researching materials and processes that could result in stronger and more reliable wind blades. "Current materials need to be optimized to meet the demanding performance needs of today's largest wind blade designs," said Cheryl Richards, PPG global marketing manager in wind energy. According to Cheryl, wind turbine blades are produced by combining dry fiber glass fabrics with a strong resin to form a composite. This method is widely used in production,

185

On the Fatigue Analysis of Wind Turbines  

DOE Green Energy (OSTI)

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.

Sutherland, Herbert J.

1999-06-01T23:59:59.000Z

186

Applications: Operational wind turbines  

E-Print Network (OSTI)

Capability Applications: Operational wind turbines Benefits: Optimize wind turbine performance Summary: Researchers at the Los Alamos National Laboratory (LANL) Intelligent Wind Turbine Program are developing a multi-physics modeling approach for the analysis of wind turbines in the presence of realistic

187

Multiple piece turbine rotor blade  

DOE Patents (OSTI)

A multiple piece turbine rotor blade with a shell having an airfoil shape and secured between a spar and a platform with the spar including a tip end piece. a snap ring fits around the spar and abuts against the spar tip end piece on a top side and abuts against a shell on the bottom side so that the centrifugal loads from the shell is passed through the snap ring and into the spar and not through a tip cap dovetail slot and projection structure.

Jones, Russell B; Fedock, John A

2013-05-21T23:59:59.000Z

188

Department of Energy to Invest up to $4 Million for Wind Turbine...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Department of Energy to Invest up to 4 Million for Wind Turbine Blade Testing Facilities Department of Energy to Invest up to 4 Million for Wind Turbine Blade Testing Facilities...

189

Airfoils for wind turbine - Energy Innovation Portal  

Airfoils for the tip and mid-span regions of a wind turbine blade have upper surface and lower surface shapes and contours between a leading edge and a trailing edge ...

190

Jet spoiler arrangement for wind turbine  

DOE Patents (OSTI)

An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the ends thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby inducing stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

Cyrus, Jack D. (Corrales, NM); Kadlec, Emil G. (Albuquerque, NM); Klimas, Paul C. (Albuquerque, NM)

1985-01-01T23:59:59.000Z

191

Jet spoiler arrangement for wind turbine  

DOE Patents (OSTI)

An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the end thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby including stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

Cyrus, J.D.; Kadlec, E.G.; Klimas, P.C.

1983-09-15T23:59:59.000Z

192

Passive load control for large wind turbines.  

DOE Green Energy (OSTI)

Wind energy research activities at Sandia National Laboratories focus on developing large rotors that are lighter and more cost-effective than those designed with current technologies. Because gravity scales as the cube of the blade length, gravity loads become a constraining design factor for very large blades. Efforts to passively reduce turbulent loading has shown significant potential to reduce blade weight and capture more energy. Research in passive load reduction for wind turbines began at Sandia in the late 1990's and has moved from analytical studies to blade applications. This paper discusses the test results of two Sandia prototype research blades that incorporate load reduction techniques. The TX-100 is a 9-m long blade that induces bend-twist coupling with the use of off-axis carbon in the skin. The STAR blade is a 27-m long blade that induces bend-twist coupling by sweeping the blade in a geometric fashion.

Ashwill, Thomas D.

2010-05-01T23:59:59.000Z

193

A multi-scale approach to statistical and model-based structural health monitoring with application to embedded sensing for wind energy  

E-Print Network (OSTI)

in a composite wind turbine rotor blade," Structural Healthdetection in composite wind turbine blades," Journal offor structural monitoring of wind turbine rotor blades," in

Taylor, Stuart Glynn

2013-01-01T23:59:59.000Z

194

A multi-scale approach to statistical and model-based structural health monitoring with application to embedded sensing for wind energy  

E-Print Network (OSTI)

in a composite wind turbine rotor blade," Structural Healthmonitoring of wind turbine rotor blades," in progress 2013.in a composite wind turbine rotor blade." The dissertation

Taylor, Stuart Glynn

2013-01-01T23:59:59.000Z

195

AIAA-2003-0694 QUANTIFICATION OF PROCESSING PARAMETERS FOR WIND TURBINE  

E-Print Network (OSTI)

AIAA-2003-0694 QUANTIFICATION OF PROCESSING PARAMETERS FOR WIND TURBINE BLADES Douglas Cairns, John of processing techniques and can be useful to wind turbine blade manufacturers to prepare processing conditions-3]. This is a consequence of the typical material architectures that are used in wind turbine blades. Figure 1

196

Structural health and prognostics management for offshore wind turbines : case studies of rotor fault and blade damage with initial O&M cost modeling.  

SciTech Connect

Operations and maintenance costs for offshore wind plants are significantly higher than the current costs for land-based (onshore) wind plants. One way to reduce these costs would be to implement a structural health and prognostic management (SHPM) system as part of a condition based maintenance paradigm with smart load management and utilize a state-based cost model to assess the economics associated with use of the SHPM system. To facilitate the development of such a system a multi-scale modeling approach developed in prior work is used to identify how the underlying physics of the system are affected by the presence of damage and faults, and how these changes manifest themselves in the operational response of a full turbine. This methodology was used to investigate two case studies: (1) the effects of rotor imbalance due to pitch error (aerodynamic imbalance) and mass imbalance and (2) disbond of the shear web; both on a 5-MW offshore wind turbine in the present report. Based on simulations of damage in the turbine model, the operational measurements that demonstrated the highest sensitivity to the damage/faults were the blade tip accelerations and local pitching moments for both imbalance and shear web disbond. The initial cost model provided a great deal of insight into the estimated savings in operations and maintenance costs due to the implementation of an effective SHPM system. The integration of the health monitoring information and O&M cost versus damage/fault severity information provides the initial steps to identify processes to reduce operations and maintenance costs for an offshore wind farm while increasing turbine availability, revenue, and overall profit.

Myrent, Noah J. [Purdue Center for Systems Integrity, Lafayette, IN; Kusnick, Joshua F. [Purdue Center for Systems Integrity, Lafayette, IN; Barrett, Natalie C. [Purdue Center for Systems Integrity, Lafayette, IN; Adams, Douglas E. [Purdue Center for Systems Integrity, Lafayette, IN; Griffith, Daniel Todd

2013-04-01T23:59:59.000Z

197

Turbine blade tip with offset squealer  

DOE Patents (OSTI)

An industrial turbine assembly comprises a plurality of rotating blade portions in a spaced relation with a stationary shroud. The rotating blade includes a root section, an airfoil having a pressure sidewall and a suction sidewall defining an outer periphery and a tip portion having a tip cap. An offset squealer is disposed on the tip cap. The offset squealer is positioned inward from the outer periphery of the rotating blade. The offset squealer increases the flow resistance and reduces the flow of hot gas flow leakage for a given pressure differential across the blade tip portion so as to improve overall turbine efficiency.

Bunker, Ronald Scott (Niskayuna, NY)

2001-01-01T23:59:59.000Z

198

Aero-Structural Optimization of a 5 MW Wind Turbine Rotor.  

E-Print Network (OSTI)

??A 5 MW wind turbine rotor blade based on the NREL 5 MW Reference Turbine is optimized for maximum efficiency and minimum flapwise hub bending (more)

Vesel, Richard W., Jr.

2012-01-01T23:59:59.000Z

199

Rotationally sampled wind characteristics and correlations with MOD-OA wind turbine response  

SciTech Connect

This report presents results of a comprehensive wind and wind turbine measurement program: the Clayton, New Mexico, vertical plane array/MOD-OA project. In this experiment, the turbulent wind was measured for a large array of fixed anemometers located two blade diameters upwind of a 200-kW horizontal-axis wind turbine (HAWT). Simultaneously, key wind turbine response parameters were also measured. The first of two major objectives of this experiment was to determine the turbulent wind, rotationally sampled to emulate the motion of the wind turbine blade, for the range of different wind speeds and stability classes actually experienced by the wind turbine. The second major objective was to correlate this rotationally sampled wind with the wind turbine blade stress and power, in order to assess the usefulness of the wind measurements for wind turbine loads testing a prediction. Time series of rotationally sampled winds and wind turbine blade bending moments and power were converted to frequency spectra using Fourier transform techniques. These spectra were used as the basis for both qualitative and quantitative comparisons among the various cases. A quantitative comparison between the rotationally sampled wind input and blade bending response was made, using the Fourier spectra to estimate the blade transfer function. These transfer functions were then used to calculate an approximate damping coefficient for the MOD-OA fiberglass blade.

George, R.L.; Connell, J.R.

1984-09-01T23:59:59.000Z

200

Wind Turbine Maintenance Guide  

Science Conference Proceedings (OSTI)

This guideline provides component-level information regarding the maintenance of major components associated with a wind turbine. It combines recommendations offered by major equipment manufacturers with lessons learned from owner/operators of wind turbine facilities.

2012-06-29T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Cooling arrangement for a tapered turbine blade  

SciTech Connect

A cooling arrangement (11) for a highly tapered gas turbine blade (10). The cooling arrangement (11) includes a pair of parallel triple-pass serpentine cooling circuits (80,82) formed in an inner radial portion (50) of the blade, and a respective pair of single radial channel cooling circuits (84,86) formed in an outer radial portion (52) of the blade (10), with each single radial channel receiving the cooling fluid discharged from a respective one of the triple-pass serpentine cooling circuit. The cooling arrangement advantageously provides a higher degree of cooling to the most highly stressed radially inner portion of the blade, while providing a lower degree of cooling to the less highly stressed radially outer portion of the blade. The cooling arrangement can be implemented with known casting techniques, thereby facilitating its use on highly tapered, highly twisted Row 4 industrial gas turbine blades that could not be cooled with prior art cooling arrangements.

Liang, George (Palm City, FL)

2010-07-27T23:59:59.000Z

202

Fast Verification of Wind Turbine Power Summary of Project Results  

E-Print Network (OSTI)

a wind turbine's design phase, the power curve can be predicted using analytical techniques such as Blade using a single cup anemometer at the wind turbine's hub height and it is assumed that this measurementFast Verification of Wind Turbine Power Curves: Summary of Project Results by: Cameron Brown ­ s

203

Stochastic Analysis of Wind Turbine Power Curves Edgar Anahua  

E-Print Network (OSTI)

procedure (IEC 61400-12) for power performance charac- terization of a single wind turbines is shown by the standard IEC 61400-12 3 [12]. In this standard procedure the power curve of a single wind turbine of the blade pitch angle system of a wind turbine [9]. The phase averaged P(t,t ) function depends on the time

Peinke, Joachim

204

Wind Turbines | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Turbines Wind Turbines July 30, 2013 - 2:58pm Addthis Energy 101: Wind Turbines Basics This video explains the basics of how wind turbines operate to produce clean power from an...

205

Wind Turbine Design Using A Free-wake Vortex Method With Winglet Application.  

E-Print Network (OSTI)

??Wind turbine blades are traditionally designed with blade element momentum theory (BEMT). This method is incapable of accurately analyzing non-conventional or non-planar blade planforms. Modern (more)

Maniaci, David

2013-01-01T23:59:59.000Z

206

The wind turbine  

Science Conference Proceedings (OSTI)

In this paper we present the modeling of a wing turbine, using the Euler Lagrange method and circuits theory. We get the mathematical equation (modeling) that describes the wind turbine and we simulate it using the mathlab program. Keywords: modeling, simulation, wind turbine

Jos De Jess Rubio Avila; Andrs Ferreira Ramrez; Genaro Deloera Flores; Martn Salazar Pereyra; Fernando Baruch Santillanes Posada

2008-07-01T23:59:59.000Z

207

NREL: Wind Research - SWIFT Wind Turbine Testing and Results  

NLE Websites -- All DOE Office Websites (Extended Search)

SWIFT Wind Turbine Testing and Results SWIFT Wind Turbine Testing and Results The SWIFT wind turbine. Text Version As part of the National Renewable Energy Laboratory and U.S. Department of Energy (NREL/DOE) Independent Testing project, NREL is testing the SWIFT small wind turbine at the National Wind Technology Center (NWTC). The competitive grant was awarded to Cascade Engineering. The SWIFT is a 1-kilowatt (kW), five-bladed with outer ring, horizontal-axis upwind small wind turbine. The turbine's rotor diameter is 2 meters, and its hub height is 13.72 meters. The SWIFT uses a single-phase permanent-magnet generator rated at 1 kW grid connected through an inverter at 240 volts AC. Testing Summary Supporting data and explanations for data provided in this table will be provided in the final reports. Data presented are preliminary and subject

208

Huayi Wind Blade Research Center | Open Energy Information  

Open Energy Info (EERE)

Huayi Wind Blade Research Center Huayi Wind Blade Research Center Jump to: navigation, search Name Huayi Wind Blade Research Center Place Baoding, Hebei Province, China Zip 71051 Sector Wind energy Product China's first research center for wind turbine blade. Coordinates 38.855011°, 115.480217° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.855011,"lon":115.480217,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

209

innovati nNREL Innovations Contribute to an Award-Winning Small Wind Turbine  

E-Print Network (OSTI)

innovati nNREL Innovations Contribute to an Award-Winning Small Wind Turbine The Skystream 3.7 wind (NREL) and Southwest Windpower, a commercially successful small wind turbine manufacturer. NREL drew blade design that makes the wind turbine more efficient and quieter than most. Small wind turbines

210

Rejuvenation of Service-Exposed in 738 Turbine Blades  

Science Conference Proceedings (OSTI)

are used as investment cast turbine blades in many aircraft gas turbine engines. In their conventionally cast polycrystalline equiaxed forms, these alloys derive...

211

Deformation Prediction of a Heavy Hydro Turbine Blade During ...  

Science Conference Proceedings (OSTI)

Presentation Title, Deformation Prediction of a Heavy Hydro Turbine Blade During ... Abstract Scope, Heavy hydro turbine castings are made of martensitic...

212

2010 Tests Examining Survival of Fish Struck By Turbine Blades  

Science Conference Proceedings (OSTI)

As part of ongoing efforts to develop environmentally enhanced hydro turbines, EPRI has been conducting studies to assess turbine blade design parameters that affect fish mortality. This report describes the third year of EPRI-funded hydro turbine blade strike testing. The goal of these studies has been to improve industry understanding of blade strike injury and mortality, primarily with respect to fish length, leading edge blade thickness, and strike velocity (relative speed of fish to blade).

2011-12-15T23:59:59.000Z

213

NREL: Wind Research - Abundant Renewable Energy's ARE 442 Wind Turbine  

NLE Websites -- All DOE Office Websites (Extended Search)

Abundant Renewable Energy's ARE 442 Wind Turbine Testing and Results Abundant Renewable Energy's ARE 442 Wind Turbine Testing and Results Get the Adobe Flash Player to see this video. A video of Abundant Renewable Energy's ARE 442 wind turbine. Text Version As part of the National Renewable Energy Laboratory and U.S. Department of Energy (NREL/DOE) Independent Testing project, NREL tested Abundant Renewable Energy's ARE 442 turbine at the National Wind Technology Center (NWTC). The ARE 442 is a 10-kilowatt (kW), three-bladed, horizontal-axis upwind small wind turbine. It has a hub height of 30.9 meters and a rotor diameter of 7.2 meters. The turbine has a single-phase permanent-magnet generator that operates at variable voltages up to 410 volts AC. Testing Summary The summary of the tests is below with the final reports.

214

NREL: Wind Research - Gaia-Wind's 11 Kilowatt Wind Turbine Testing and  

NLE Websites -- All DOE Office Websites (Extended Search)

Gaia-Wind's 11 Kilowatt Wind Turbine Testing and Results Gaia-Wind's 11 Kilowatt Wind Turbine Testing and Results A video of Gaia-Wind's 11-kW wind turbine. Text Version As part of the National Renewable Energy Laboratory and U.S. Department of Energy (NREL/DOE) Independent Testing project, NREL tested Gaia-Wind's 11-kilowatt (kW) small wind turbine at the National Wind Technology Center (NWTC). Gaia-Wind's turbine is a three-phase induction generator that operates at 480 volts. The turbine's downwind rotor has a 13-meter diameter, and its tower is 18 meters tall. The two-bladed, oversized rotor is designed for low to moderate wind speeds. Testing Summary The summary of the tests is below with the final reports. Cumulative Energy Production 6/11/2008: 210; 6/13/2008: 528; 6/16/2008: 716; 6/18/2008: 731; 6/19/2008:

215

Definition of a 5-MW Reference Wind Turbine for Offshore System Development  

SciTech Connect

This report describes a three-bladed, upwind, variable-speed, variable blade-pitch-to-feather-controlled multimegawatt wind turbine model developed by NREL to support concept studies aimed at assessing offshore wind technology.

Jonkman, J.; Butterfield, S.; Musial, W.; Scott, G.

2009-02-01T23:59:59.000Z

216

Aerodynamic interference between two Darrieus wind turbines  

DOE Green Energy (OSTI)

The effect of aerodynamic interference on the performance of two curved bladed Darrieus-type vertical axis wind turbines has been calculated using a vortex/lifting line aerodynamic model. The turbines have a tower-to-tower separation distance of 1.5 turbine diameters, with the line of turbine centers varying with respect to the ambient wind direction. The effects of freestream turbulence were neglected. For the cases examined, the calculations showed that the downwind turbine power decrement (1) was significant only when the line of turbine centers was coincident with the ambient wind direction, (2) increased with increasing tipspeed ratio, and (3) is due more to induced flow angularities downstream than to speed deficits near the downstream turbine.

Schatzle, P.R.; Klimas, P.C.; Spahr, H.R.

1981-04-01T23:59:59.000Z

217

Volumetric Geometry Reconstruction of Turbine Blades for Aircraft Engines  

E-Print Network (OSTI)

Volumetric Geometry Reconstruction of Turbine Blades for Aircraft Engines David Gro?mann1 and Bert-spline parametrization of turbine blades from measurement data generated by optical scanners. This new representation elements. We focus on the industrial applicability of the framework, by using standard turbine blade

Jüttler, Bert

218

Innovative wind turbines. Circulation controlled vertical axis wind turbine. Progress report, March 1-December 31, 1976  

DOE Green Energy (OSTI)

Theoretical and experimental research efforts in evaluating an innovative concept for vertical axis wind turbines (VAWT) are described. The concept is that of using straight blades composed of circulation controlled airfoil sections. The theoretical analysis has been developed to determine the unsteady lift and moment characteristics of multiple-blade cross-flow wind turbines. To determine the drag data needed as input to the theoretical analysis, an outdoor test model VAWT has been constructed; design details, instrumentation, and calibration results are reported. Initial testing is with fixed pitch blades having cross-sections of conventional symmetrical airfoils. Costs of building the test model are included, as well as estimates for blades constructed with composite materials. These costs are compared with those of other types of wind turbines.

Walters, R. E.; Fanucci, J. B.; Hill, P. W.; Migliore, P. G.; Squire, W.; Waltz, T. L.

1978-10-01T23:59:59.000Z

219

NREL: Wind Research - Small Wind Turbine Development  

NLE Websites -- All DOE Office Websites (Extended Search)

Small Wind Turbine Development Small Wind Turbine Development A photo of Southwest Windpower's Skystream wind turbine in front of a home. PIX14936 Southwest Windpower's Skystream wind turbine. A photo of the Endurance wind turbine. PIX15006 The Endurance wind turbine. A photo of the Atlantic Orient Corporation 15/50 wind turbine at the National Wind Technology Center. PIX07301 The Atlantic Orient Corporation 15/50 wind turbine at the National Wind Technology Center. NREL supports continued market expansion of small wind turbines by funding manufacturers through competitive solicitations (i.e., subcontracts and/or grants) to refine prototype systems leading to commercialization. Learn more about the turbine development projects below. Skystream NREL installed and tested an early prototype of this turbine at the

220

Helicoidal vortex model for wind turbine aeroelastic simulation  

Science Conference Proceedings (OSTI)

The vortex method has been extended to account for blade flexibility, which is a potential source of unsteadiness in the flow past a wind turbine rotor. The code has been validated previously under the assumption of rigid blades. The aerodynamics method ... Keywords: Blade flexibility, Steady and unsteady flows, Tower interference, Vortex model

Jean-Jacques Chattot

2007-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Real time wind turbine simulator.  

E-Print Network (OSTI)

??A novel dynamic real-time wind turbine simulator (WTS) is developed in this thesis, which is capable of reproducing dynamic behavior of real wind turbine. The (more)

Gong, Bing

2007-01-01T23:59:59.000Z

222

Wind shear for large wind turbine generators at selected tall tower sites  

DOE Green Energy (OSTI)

The objective of the study described in this report is to examine the nature of wind shear profiles and their variability over the height of large horizontal-axis wind turbines and to provide information on wind shear relevant to the design and opertion of large wind turbines. Wind turbine fatigue life and power quality are related through the forcing functions on the blade to the shapes of the wind shear profiles and their fluctuations over the disk of rotation.

Elliott, D.L.

1984-04-01T23:59:59.000Z

223

A surface definition code for turbine blade surfaces  

DOE Green Energy (OSTI)

A numerical interpolation scheme has been developed for generating the three-dimensional geometry of wind turbine blades. The numerical scheme consists of (1) creating the frame of the blade through the input of two or more airfoils at some specific spanwise stations and then scaling and twisting them according to the prescribed distributions of chord, thickness, and twist along the span of the blade; (2) transforming the physical coordinates of the blade frame into a computational domain that complies with the interpolation requirements; and finally (3) applying the bi-tension spline interpolation method, in the computational domain, to determine the coordinates of any point on the blade surface. Detailed descriptions of the overall approach to and philosophy of the code development are given along with the operation of the code. To show the usefulness of the bi-tension spline interpolation code developed, two examples are given, namely CARTER and MICON blade surface generation. Numerical results are presented in both graphic data forms. The solutions obtained in this work show that the computer code developed can be a powerful tool for generating the surface coordinates for any three-dimensional blade.

Yang, S.L. [Michigan Technological Univ., Houghton, MI (United States); Oryang, D.; Ho, M.J. [Tuskegee Univ., AL (United States)

1992-05-01T23:59:59.000Z

224

Wind shear climatology for large wind turbine generators  

DOE Green Energy (OSTI)

Climatological wind shear analyses relevant to the design and operation of multimegawatt wind turbines are provided. Insight is provided for relating the wind experienced by a rotating blade in a shear flow to the analysis results. A simple analysis of the wind experienced by a rotating blade for three types of wind shear profiles under steady-state conditions is presented in graphical form. Comparisons of the magnitude and frequency of the variations in 1) the wind sensed by a single blade element, 2) the sum, and 3) the difference of the winds sensed by opposite blade elements show strong sensitivity to profile shape. These three items represent forcing functions that can be related to 1) flatwise bending moment, 2) torque on the shaft, and 3) teeter angle. A computer model was constructed to simulate rotational sampling of 10-s sampled winds from a tall tower for three different types of large wind turbines. Time series produced by the model indicated that the forcing functions on a rotating blade vary according to the shear profile encountered during each revolution as opposed to a profile derived from average wind conditions, e.g., hourly average winds. An analysis scheme was developed to establish a climatology of wind shear profiles derived from 10-s sampled winds and hourly average winds measured over a one-year period at several levels on a tall tower. Because of the sensitivity of the forcing function variability to profile shape, the analyses performed and presented are in the form of joint frequency distributions of velocity differences of the the top-to-hub versus the hub-to-bottom portion of disks of rotation for the three turbine configurations.

Elliott, D.L.; Wendell, L.L.; Heflick, S.K.

1982-10-01T23:59:59.000Z

225

Vertical axis wind turbine development. Executive summary. Final report, March 1, 1976-June 30, 1977  

DOE Green Energy (OSTI)

Information is presented concerning the numerical solution of the aerodynamics of cross-flow wind turbines; boundary layer considerations for a vertical axis wind turbine; WVU VAWT outdoor test model; low solidity blade tests; high solidity blade design; cost analysis of the WVU VAWT test model; structural parametric analysis of VAWT blades; and cost study of current WECS.

Walters, R. E.; Fanucci, J. B.; Hill, P. W.; Migliore, P. G.

1979-07-01T23:59:59.000Z

226

Blades of Glory: Wind Technology Bringing Us Closer To a Clean Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Blades of Glory: Wind Technology Bringing Us Closer To a Clean Blades of Glory: Wind Technology Bringing Us Closer To a Clean Energy Future Blades of Glory: Wind Technology Bringing Us Closer To a Clean Energy Future July 17, 2012 - 2:14pm Addthis Niketa Kumar Niketa Kumar Public Affairs Specialist, Office of Public Affairs What does this project do? The Energy Department is supporting the validation of newly developed technologies at wind testing facilities across America. There's a simple truth in wind energy -- the bigger the blade, the more watts generated. 

In the 1980s, blades were typically 65 feet long. Today, as the wind industry continues to grow, blades measure over 150 feet. Looking down the road, the next generation of wind turbine blades is expected to span beyond the length of a football field.



227

Wind turbine | Open Energy Information  

Open Energy Info (EERE)

turbine turbine Jump to: navigation, search Dictionary.png Wind turbine: A machine that converts wind energy to mechanical energy; typically connected to a generator to produce electricity. Other definitions:Wikipedia Reegle Contents 1 Types of Wind Turbines 1.1 Vertical Axis Wind Turbines 1.2 Horizontal Axis Wind Turbines 2 Wind Turbine Sizes 3 Components of a Wind Turbine 4 References Types of Wind Turbines There are two basic wind turbine designs: those with a vertical axis (sometimes referred to as VAWTs) and those with a horizontal axis (sometimes referred to as HAWTs). There are several manufacturers of vertical axis turbines, but they have not penetrated the "utility scale" (100 kW capacity and larger) market to the same degree as horizontal axis turbines.[1]

228

Wind Turbine Manufacturing Process Monitoring  

SciTech Connect

To develop a practical inline inspection that could be used in combination with automated composite material placement equipment to economically manufacture high performance and reliable carbon composite wind turbine blade spar caps. The approach technical feasibility and cost benefit will be assessed to provide a solid basis for further development and implementation in the wind turbine industry. The program is focused on the following technology development: (1) Develop in-line monitoring methods, using optical metrology and ultrasound inspection, and perform a demonstration in the lab. This includes development of the approach and performing appropriate demonstration in the lab; (2) Develop methods to predict composite strength reduction due to defects; and (3) Develop process models to predict defects from leading indicators found in the uncured composites.

Waseem Faidi; Chris Nafis; Shatil Sinha; Chandra Yerramalli; Anthony Waas; Suresh Advani; John Gangloff; Pavel Simacek

2012-04-26T23:59:59.000Z

229

Influence of refraction on wind turbine noise  

E-Print Network (OSTI)

A semi-empirical method is applied to calculate the time-average sound level of wind turbine noise generation and propagation. Both are affected by wind shear refraction. Under upwind conditions the partially ensonified zone separates the fully ensonified zone (close to the turbine) and the shadow zone (far away from the turbine). Refraction is described in terms of the wind speed linear profile fitted to the power law profile. The rotating blades are treated as a two-dimensional circular source in the vertical plane. Inside the partially ensonified zone the effective A-weighted sound power decreases to zero when the receiver moves from the turbine toward the shadow zone. The presented results would be useful in practical applications to give a quick estimate of the effect of refraction on wind turbine noise.

Makarewicz, Rufin

2013-01-01T23:59:59.000Z

230

Influence of Control on the Pitch Damping of a Floating Wind Turbine  

SciTech Connect

This paper presents the influence of conventional wind turbine blade-pitch control actions on the pitch damping of a wind turbine supported by an offshore floating barge with catenary moorings.

Jonkman, J. M.

2008-03-01T23:59:59.000Z

231

Blade Testing at NREL's National Wind Technology Center (NWTC) (Presentation)  

DOE Green Energy (OSTI)

Presentation of Blade Testing at NREL's National Wind Technology Center for the 2010 Sandia National Laboratories Blade Testing Workshop.

Hughes, S.

2010-07-20T23:59:59.000Z

232

NREL: Wind Research - Large Wind Turbine Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Wind Research Search More Search Options Site Map Printable Version Large Wind Turbine Research NREL's utility scale wind system research addresses performance and...

233

Wind turbine rotor hub and teeter joint  

DOE Patents (OSTI)

A rotor hub is provided for coupling a wind turbine rotor blade and a shaft. The hub has a yoke with a body which is connected to the shaft, and extension portions which are connected to teeter bearing blocks, each of which has an aperture. The blocks are connected to a saddle which envelops the rotor blade by one or two shafts which pass through the apertures in the bearing blocks. The saddle and blade are separated by a rubber interface which provides for distribution of stress over a larger portion of the blade. Two teeter control mechanisms, which may include hydraulic pistons and springs, are connected to the rotor blade and to the yoke at extension portions. These control mechanisms provide end-of-stroke damping, braking, and stiffness based on the teeter angle and speed of the blade.

Coleman, Clint (Warren, VT); Kurth, William T. (Warren, VT); Jankowski, Joseph (Stowe, VT)

1994-10-11T23:59:59.000Z

234

Fatigue of Wind Blade Laminates:Fatigue of Wind Blade Laminates: Effects of Resin and Fabric Structure  

E-Print Network (OSTI)

Fatigue of Wind Blade Laminates:Fatigue of Wind Blade Laminates: Effects of Resin and Fabric University MCARE 2012 #12;Outline · Overview of MSU Fatigue Program on Wind Blade MaterialsWind Blade Wind Blade Component Materials Acknowledgements: Sandia National Laboratories/DOE (Joshua Paquette

235

Airfoils for wind turbine  

DOE Patents (OSTI)

Airfoils for the tip and mid-span regions of a wind turbine blade have upper surface and lower surface shapes and contours between a leading edge and a trailing edge that minimize roughness effects of the airfoil and provide maximum lift coefficients that are largely insensitive to roughness effects. The airfoil in one embodiment is shaped and contoured to have a thickness in a range of about fourteen to seventeen percent, a Reynolds number in a range of about 1,500,000 to 2,000,000, and a maximum lift coefficient in a range of about 1.4 to 1.5. In another embodiment, the airfoil is shaped and contoured to have a thickness in a range of about fourteen percent to sixteen percent, a Reynolds number in a range of about 1,500,000 to 3,000,000, and a maximum lift coefficient in a range of about 0.7 to 1.5. Another embodiment of the airfoil is shaped and contoured to have a Reynolds in a range of about 1,500,000 to 4,000,000, and a maximum lift coefficient in a range of about 1.0 to 1.5.

Tangler, James L. (Boulder, CO); Somers, Dan M. (State College, PA)

2000-01-01T23:59:59.000Z

236

Active load control techniques for wind turbines.  

DOE Green Energy (OSTI)

This report provides an overview on the current state of wind turbine control and introduces a number of active techniques that could be potentially used for control of wind turbine blades. The focus is on research regarding active flow control (AFC) as it applies to wind turbine performance and loads. The techniques and concepts described here are often described as 'smart structures' or 'smart rotor control'. This field is rapidly growing and there are numerous concepts currently being investigated around the world; some concepts already are focused on the wind energy industry and others are intended for use in other fields, but have the potential for wind turbine control. An AFC system can be broken into three categories: controls and sensors, actuators and devices, and the flow phenomena. This report focuses on the research involved with the actuators and devices and the generated flow phenomena caused by each device.

van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.; Johnson, Scott J. (University of California, Davis, CA)

2008-07-01T23:59:59.000Z

237

NREL: Wind Research - Small Wind Turbine Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Small Wind Turbine Research Small Wind Turbine Research The National Renewable Energy Laboratory and U.S. Department of Energy (NREL/DOE) Small Wind Project's objectives are to reduce barriers to wind energy expansion, stabilize the market, and expand the number of small wind turbine systems installed in the United States. "Small wind turbine" refers to a turbine smaller than or equal to 100 kilowatts (kW). "Distributed wind" includes small and midsize turbines (100 kW through 1 megawatt [MW]). Since 1996, NREL's small wind turbine research has provided turbine testing, turbine development, and prototype refinement leading to more commercially available small wind turbines. Work is conducted under the following areas. You can also learn more about state and federal policies

238

Rotor blades for turbine engines  

DOE Patents (OSTI)

A tip shroud that includes a plurality of damping fins, each damping fin including a substantially non-radially-aligned surface that is configured to make contact with a tip shroud of a neighboring rotor blade. At least one damping fin may include a leading edge damping fin and at least one damping fin may include a trailing edge damping fin. The leading edge damping fin may be configured to correspond to the trailing edge damping fin.

Piersall, Matthew R; Potter, Brian D

2013-02-12T23:59:59.000Z

239

Operation of a third generation wind turbine  

SciTech Connect

A modern wind turbine was installed on May 26, 1982, at the USDA Conservation and Production Research Laboratory, Bushland, Texas. This wind machine was used to provide electrical energy for irrigation pumping and other agricultural loads. The wind turbine purchased for this research is an Enertech Model 44, manufactured by Enertech Corporation, Norwich, Vermont. The horizontal-axis wind turbine has a 13.4 m diameter, three-bladed, fixed-pitch rotor on a 24.4-m tower. The blades are laminated epoxy-wood, and are attached to a steel hub. A 25-kW induction generator provides 240 V, 60 Hz, single-phase electrical power. The wind turbine operated 64 percent of the time, while being available to operate over 94 percent of the time. The unit had a net energy production of over 80,000 kWh in an average windspeed of 5.9 m/s at a height of 10 m in a 16-month period. The blade pitch was originally offset two degrees from design to maintain power production within the limitations of the gearbox, generator, and brakes. A maximum output of 23.2 kW averaged over a 15-second period indicated that with a new brake, the system was capable of handling more power. After a new brake was installed, the blade pitch was changed to one degree from design. The maximum power output measured after the pitch change was 29.3 kW. Modified blade tip brakes were installed on the wind turbine on July 7, 1983. These tip brakes increased power production at lower windspeeds while reducing power at higher windspeeds.

Vosper, F.C.; Clark, R.N.

1983-12-01T23:59:59.000Z

240

Root region airfoil for wind turbine  

DOE Patents (OSTI)

A thick airfoil for the root region of the blade of a wind turbine. The airfoil has a thickness in a range from 24%-26% and a Reynolds number in a range from 1,000,000 to 1,800,000. The airfoil has a maximum lift coefficient of 1.4-1.6 that has minimum sensitivity to roughness effects.

Tangler, James L. (Boulder, CO); Somers, Dan M. (State College, PA)

1995-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Reconstruction of steam turbine blade twisted based on NURBS surface  

Science Conference Proceedings (OSTI)

NURBS (Non-Uniform Rational B-Spline) is the most popular mathematical descriptor for surface modeling. To construct steam turbine blade efficiently and accurately, 23 NURBS was obtained to fitted blade surface as its cross-section is different tangent ... Keywords: steam turbine blade, surface modeling, NURBS surfac, reconstruction

Yue Ying; Wang Zhangqi; Han Qingyao

2010-06-01T23:59:59.000Z

242

UNSTEADY SIMULATION OF FLOW IN MICRO VERTICAL AXIS WIND TURBINE  

E-Print Network (OSTI)

Though wind turbines and windmills have been used for centuries, the application of aerodynamics technology to improve reliability and reduce costs of wind-generated energy has only been pursued in earnest for the past 40 years. Today, wind energy is mainly used to generate electricity. Wind is a renewable energy source. Power production from wind turbines is affected by certain conditions: wind speed, turbine speed, turbulence and the changes of wind direction. These conditions are not always optimal and have negative effects on most turbines. The present turbine is supposed to be less affected by these conditions because the blades combine a rotating movement around each own axis and around the nacelles one. Due to this combination of movements, flow around this turbine can be more highly unsteady, because of great blade stagger angles. The turbine has a rotor with three straight blades of symmetrical airfoil. Paper presents unsteady simulations that have been performed for one wind velocity, and different initial blades stagger angles. The influence of interaction of blades is studied for one specific constant rotational speed among the four rotational speeds that have been studied.

A. C. Bayeul-lain; G. Bois

2013-01-01T23:59:59.000Z

243

NREL: Wind Research - Midsize Wind Turbine Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Midsize Wind Turbine Research Midsize Wind Turbine Research To facilitate the development and commercialization of midsize wind turbines (turbines with a capacity rating of more than 100 kW up to 1 MW), the U.S. Department of Energy (DOE) and NREL launched the Midsize Wind Turbine Development Project. In its latest study, NREL determined that there is a substantial market for midsize wind turbines. One of the most significant barriers to the midsize turbine market is the lack of turbines available for deployment; there are few midsize turbines on the market today. The objectives of the Midsize Wind Turbine Development Project are to reduce the barriers to wind energy expansion by filling an existing domestic technology gap; facilitate partnerships; accelerate maturation of existing U.S. wind energy businesses; and incorporate process improvement

244

Wind turbine rotor hub and teeter joint - Energy Innovation Portal  

A rotor hub is provided for coupling a wind turbine rotor blade and a shaft. The hub has a yoke with a body which is connected to the shaft, and extension portions ...

245

Modelling the aerodynamics of vertical-axis wind turbines.  

E-Print Network (OSTI)

??The current generation of wind turbines that are being deployed around the world features, almost exclusively, a three-bladed rotor with a horizontal-axis configuration. In recent (more)

Scheurich, Frank

2011-01-01T23:59:59.000Z

246

Experimental Investigation of Film Cooling Effectiveness on Gas Turbine Blades  

E-Print Network (OSTI)

High turbine inlet temperature becomes necessary for increasing thermal efficiency of modern gas turbines. To prevent failure of turbine components, advance cooling technologies have been applied to different portions of turbine blades. The detailed film cooling effectiveness distributions along a rotor blade has been studied under combined effects of upstream trailing edge unsteady wake with coolant ejection by the pressure sensitive paint (PSP). The experiment is conducted in a low speed wind tunnel with a five blade linear cascade and exit Reynolds number is 370,000. The density ratios for both blade and trailing edge coolant ejection range from 1.5 to 2.0. Blade blowing ratios are 0.5 and 1.0 on suction surface and 1.0 and 2.0 on pressure surface. Trailing edge jet blowing ratio and Strouhal number are 1.0 and 0.12, respectively. Results show the unsteady wake reduces overall effectiveness. However, the unsteady wake with trailing edge coolant ejection enhances overall effectiveness. Results also show that the overall effectiveness increases by using heavier coolant for ejection and blade film cooling. Leading edge film cooling has been investigated using PSP. There are two test models: seven and three-row of film holes for simulating vane and blade, respectively. Four film holes configurations are used for both models: radial angle cylindrical holes, compound angle cylindrical holes, radial angle shaped holes, and compound angle shaped holes. Density ratios are 1.0 to 2.0 while blowing ratios are 0.5 to 1.5. Experiments were conducted in a low speed wind tunnel with Reynolds number 100,900. The turbulence intensity near test model is about 7%. The results show the shaped holes have overall higher effectiveness than cylindrical holes for both designs. As increasing density ratio, density effect on shaped holes becomes evident. Radial angle holes perform better than compound angle holes as increasing blowing and density ratios. Increasing density ratio generally increases overall effectiveness for all configurations and blowing ratios. One exception occurs for compound angle and radial angle shaped hole of three-row design at lower blowing ratio. Effectiveness along stagnation row reduces as increasing density ratio due to coolant jet with insufficient momentum caused by heavier density coolant, shaped hole, and stagnation row.

Li, Shiou-Jiuan

2012-12-01T23:59:59.000Z

247

Effects of blade configuration on flow distribution and power output of a zephyr vertical axis wind turbine.  

E-Print Network (OSTI)

??Worldwide interest in renewable energy systems has increased dramatically, due to environmental concerns like climate change and other factors. Wind power is a major source (more)

Ajedegba, John Oviemuno

2008-01-01T23:59:59.000Z

248

Vertical axis wind turbines  

DOE Patents (OSTI)

A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

Krivcov, Vladimir (Miass, RU); Krivospitski, Vladimir (Miass, RU); Maksimov, Vasili (Miass, RU); Halstead, Richard (Rohnert Park, CA); Grahov, Jurij (Miass, RU)

2011-03-08T23:59:59.000Z

249

Multiblade Coordinate Transformation and Its Application to Wind Turbine Analysis: Preprint  

SciTech Connect

This paper describes the mulitblade coordinate transformation (MBC) modeling process that integrates the dynamics of individual wind turbine blades and expresses them as fixed frames.

Bir, G.

2008-01-01T23:59:59.000Z

250

Wind Turbine Acoustic Noise A white paper  

E-Print Network (OSTI)

Wind Turbine Acoustic Noise A white paper Prepared by the Renewable Energy Research Laboratory...................................................................... 8 Sound from Wind Turbines .............................................................................................. 10 Sources of Wind Turbine Sound

Massachusetts at Amherst, University of

251

Multiscale Modelling of Single Crystal Superalloys for Gas Turbine Blades  

E-Print Network (OSTI)

Multiscale Modelling of Single Crystal Superalloys for Gas Turbine Blades PROEFSCHRIFT ter Multiscale Modelling of Single Crystal Superalloys for Gas Turbine Blades / by Tiedo Tinga. ­ Eindhoven accumulation 120 5.5 Application 121 5.6 Summary and conclusions 128 6. Application to gas turbine parts 131 6

252

Advanced Airfoils for Wind Turbines: Office of Power Technologies (OPT) Success Stories Series Fact Sheet  

NLE Websites -- All DOE Office Websites (Extended Search)

Program Program Office of Geothermal and Wind Technologies Blades are where the turbine meets the wind. Turbine blades take advantage of aero- dynamics to extract the wind's energy, which can then be converted to useful electricity. Airfoils-the cross-sectional shape of the blades-determine the aerodynamic forces on blades. They are key to blade design. In the seventies, the young and fast-growing U.S. wind industry used airfoil designs from airplane wings to design turbine blades because those airfoil designs were widely available, and engineers understood how they performed on aircraft. Airfoils specifically designed for wind turbines did not yet exist. The industry quickly learned, however, how harsh the operating environment is for wind turbines as compared to that for airplanes.

253

Infrared Probe for Application to Steam Turbine Blade Vibration Detection  

Science Conference Proceedings (OSTI)

Technology for non-contacting steam turbine blade tip vibration measurement has advanced to the point of being a viable tool for risk management in situations where turbine blade high-cycle vibration occurs as a result of operating parameters or blade condition. This report describes the development and prototype testing of a new type of blade tip time-of-arrival sensing system for use with commercial signal processing systems.

2004-12-16T23:59:59.000Z

254

Effects of Materials Parameters and Design Details on the Fatigue of Composite Materials for Wind Turbine Blades  

DOE Green Energy (OSTI)

This paper presents an analysis of the results of nine years of fatigue testing represented in the USDOE/Montana State University (DOE/MSU) Composite Materials Fatigue Database. The focus of the program has been to explore a broad range of glass-fiber-based materials parameters encompassing over 4500 data points for 130 materials systems. Significant trends and transitions in fatigue resistance are shown as the fiber content and fabric architecture are varied. The effects of structural details including ply drops, bonded stiffeners, and other geometries that produce local variations in fiber packing and geometry are also described. Fatigue tests on composite beam structures are then discussed; these show generally good correlation with coupon fatigue data in the database. Goodman diagrams for fatigue design are presented, and their application to predicting the service lifetime of blades is described.

Mandell, J.F.; Samborsky, D.D.; Sutherland, H.J.

1999-03-04T23:59:59.000Z

255

The Development of Single Crystal Superalloy Turbine Blades  

Science Conference Proceedings (OSTI)

Airbus Industries A310 aircraft. Engine certification and initial production shipments are planned for July of 1980. Alloy 454 turbine blades have also been ...

256

3D Modeling of Dendritic Grain Structures in Turbine Blade ...  

Science Conference Proceedings (OSTI)

modern aircraft engines and land-based power-plants. .... Figure 2 illustrates the grid generation for a close-up detail of a turbine blade geometry. (junction...

257

Radar-cross-section reduction of wind turbines. part 1.  

SciTech Connect

In recent years, increasing deployment of large wind-turbine farms has become an issue of growing concern for the radar community. The large radar cross section (RCS) presented by wind turbines interferes with radar operation, and the Doppler shift caused by blade rotation causes problems identifying and tracking moving targets. Each new wind-turbine farm installation must be carefully evaluated for potential disruption of radar operation for air defense, air traffic control, weather sensing, and other applications. Several approaches currently exist to minimize conflict between wind-turbine farms and radar installations, including procedural adjustments, radar upgrades, and proper choice of low-impact wind-farm sites, but each has problems with limited effectiveness or prohibitive cost. An alternative approach, heretofore not technically feasible, is to reduce the RCS of wind turbines to the extent that they can be installed near existing radar installations. This report summarizes efforts to reduce wind-turbine RCS, with a particular emphasis on the blades. The report begins with a survey of the wind-turbine RCS-reduction literature to establish a baseline for comparison. The following topics are then addressed: electromagnetic model development and validation, novel material development, integration into wind-turbine fabrication processes, integrated-absorber design, and wind-turbine RCS modeling. Related topics of interest, including alternative mitigation techniques (procedural, at-the-radar, etc.), an introduction to RCS and electromagnetic scattering, and RCS-reduction modeling techniques, can be found in a previous report.

Brock, Billy C.; Loui, Hung; McDonald, Jacob J.; Paquette, Joshua A.; Calkins, David A.; Miller, William K.; Allen, Steven E.; Clem, Paul Gilbert; Patitz, Ward E.

2012-03-05T23:59:59.000Z

258

Streamlining blade production would reduce turbine costs  

SciTech Connect

Gas turbine technology's overall future will see continuing increases in both size and higher operating temperatures, each contributing to improved energy conversion efficiency and reduced comparative capital outlay. Manufacturing technology will become even more relevant as blades acquire more sophisticated cooling or adopt the use of exotic refractory material such as crystal fibers and ceramics or both. The trend towards rising temperatures will continue. The incentives are high when it is realized that for every 100/sup 0/C increase in firing temperature there is a gain of approximately 18 percent in machine output and 2.7 percent increase in thermal efficiency.

Graham-Bryce, A.

1976-03-01T23:59:59.000Z

259

Airborne Wind Turbine  

Science Conference Proceedings (OSTI)

Broad Funding Opportunity Announcement Project: Makani Power is developing an Airborne Wind Turbine (AWT) that eliminates 90% of the mass of a conventional wind turbine and accesses a stronger, more consistent wind at altitudes of near 1,000 feet. At these altitudes, 85% of the country can offer viable wind resources compared to only 15% accessible with current technology. Additionally, the Makani Power wing can be economically deployed in deep offshore waters, opening up a resource which is 4 times greater than the entire U.S. electrical generation capacity. Makani Power has demonstrated the core technology, including autonomous launch, land, and power generation with an 8 meter wingspan, 20 kW prototype. At commercial scale, Makani Power aims to develop a 600 kW, 28 meter wingspan product capable of delivering energy at an unsubsidized cost competitive with coal, the current benchmark for low-cost power.

None

2010-09-01T23:59:59.000Z

260

Steam Turbine Blade Failure Root Cause Analysis Guide  

Science Conference Proceedings (OSTI)

Steam Turbine Blade Failure Root Cause Analysis Guide is a concise reference written for operators to plan and conduct an investigation into the most probable causes of a steam turbine blade (bucket) failure. The report provides both an overview and step-by-step approach to identifying the damage mechanisms most common to turbine blade failures. It proceeds to show how damage mechanisms are related to the operating history prior to the blades failure and how they are evaluated to establish their role as ...

2008-03-31T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Preliminary design and viability consideration of external, shroud-based stators in wind turbine generators  

E-Print Network (OSTI)

Horizontal-axis wind turbine designs often included gearboxes or large direct-drive generators to compensate for the low peripheral speeds of the turbine hub. To take advantage of high blade tip speeds, an alternative ...

Shoemaker-Trejo, Nathaniel (Nathaniel Joseph)

2012-01-01T23:59:59.000Z

262

Resonant Vibrations Resulting from the Re-Engineering of a Constant-Speed 2-Bladed Turbine to a Variable-Speed 3-Bladed Turbine  

SciTech Connect

The CART3 (Controls Advanced Research Turbine, 3-bladed) at the National Wind Technology Center has recently been converted from a 2-bladed constant speed machine to a 3-bladed variable speed machine designed specically for controls research. The purpose of this conversion was to develop an advanced controls field-testing platform which has the more typical 3-bladed configuration. A result of this conversion was the emergence of several resonant vibrations, some of which initially prevented operation of the turbine until they could be explained and resolved. In this paper, the investigations into these vibrations are presented as 'lessons-learned'. Additionally, a frequency-domain technique called waterfall plotting is discussed and its usefulness in this research is illustrated.

Fleming, P.; Wright, A. D.; Finersh, L. J.

2010-12-01T23:59:59.000Z

263

Resonant Vibrations Resulting from the Re-Engineering of a Constant-Speed 2-Bladed Turbine to a Variable-Speed 3-Bladed Turbine  

DOE Green Energy (OSTI)

The CART3 (Controls Advanced Research Turbine, 3-bladed) at the National Wind Technology Center has recently been converted from a 2-bladed constant speed machine to a 3-bladed variable speed machine designed specically for controls research. The purpose of this conversion was to develop an advanced controls field-testing platform which has the more typical 3-bladed configuration. A result of this conversion was the emergence of several resonant vibrations, some of which initially prevented operation of the turbine until they could be explained and resolved. In this paper, the investigations into these vibrations are presented as 'lessons-learned'. Additionally, a frequency-domain technique called waterfall plotting is discussed and its usefulness in this research is illustrated.

Fleming, P.; Wright, A. D.; Finersh, L. J.

2010-12-01T23:59:59.000Z

264

Tornado type wind turbines  

DOE Patents (OSTI)

A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

Hsu, Cheng-Ting (Ames, IA)

1984-01-01T23:59:59.000Z

265

Study on Aerodynamic Design of Horizontal Axis Wind Turbine Generator System  

Science Conference Proceedings (OSTI)

In this paper the choosing principles of design parameters and multi-airfoils in horizontal axis wind turbine (HAWT) generator system aerodynamic design are introduced. On the basis of the comparison analysis of wind turbine aerodynamic design method ... Keywords: Schmitz, airfoil, partial load, horizontal axis wind turbine (HAWT), blade tip speed ratio (BTSR)

Li Dong; Mingfu Liao; Yingfeng Li; Xiaoping Song; Ke Xu

2009-10-01T23:59:59.000Z

266

A neural network control strategy for improved energy capture on a variable-speed wind turbine  

Science Conference Proceedings (OSTI)

Pitch control has so far been the dominating method for power control in modern variable speed wind turbines. This paper proposes an improved control technique for pitching the blades of a variable speed wind turbine, using Artificial Neural Networks ... Keywords: artificial neural networks, control trajectories, pitch control, variable-speed wind turbines

Antnio F. Silva; Fernando A. Castro; Jos N. Fidalgo

2005-06-01T23:59:59.000Z

267

Turbine blade having a constant thickness airfoil skin  

SciTech Connect

A turbine blade is provided for a gas turbine comprising: a support structure comprising a base defining a root of the blade and a framework extending radially outwardly from the base, and an outer skin coupled to the support structure framework. The skin has a generally constant thickness along substantially the entire radial extent thereof. The framework and the skin define an airfoil of the blade.

Marra, John J; McNamee, Sara

2012-10-23T23:59:59.000Z

268

NREL: Awards and Honors - North Wind 100/20 Wind Turbine  

NLE Websites -- All DOE Office Websites (Extended Search)

North Wind 100/20 Wind Turbine North Wind 100/20 Wind Turbine Developers: Gerry Nix and Brian Smith, National Renewable Energy Laboratory; Johnathan Lynch, Clint Coleman, Garrett Bywaters, and Rob Roland, Norhtern Power Systems; Dr. David Bubenheim and Michael Flynn, NASA Ames Research Center; and John Rand, National Science Foundation. The North Wind 100/20 Wind Turbine is a state-of-the-art wind turbine that is ideal for extreme cold conditions perfect for remote locations that may be off-grid or local-grid. The numeric designations represent the North Wind's capacity, 100-kilowatts (which is enough energy for 25-50 homes), and 20-meter diameter blades. The size of the North Wind 100/20 is unique, fitting an important market niche between large and small turbines. Large turbines (400-kilowatts and

269

Identification of Wind Turbine Response to Turbulent Inflow Structures: Preprint  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory conducted an experiment to obtain detailed wind measurements and corresponding wind turbine measurements in order to establish a causal relationship between coherent turbulent structures and wind turbine blade fatigue loads. Data were collected for one entire wind season from October 2000 to May 2001. During this period, the wind turbine operated under atmospheric conditions that support the formation of coherent turbulent structures 31% of the time. Using the equivalent fatigue load parameter as a measure of wind turbine blade fatigue and using statistical measures of the turbulent fluctuations of the wind, general correlation between the turbulence and the wind turbine response is shown. Direct correlation cannot be resolved with 10-minute statistics for several reasons. Multiple turbulent structures can exist within a 10-minute record, and the equivalent fatigue load parameter is essentially a 10-minute statistic that cannot estimate turbine response to individual turbulent structures. Large-magnitude turbulent fluctuations in the form of instantaneous Reynolds stresses do not necessarily correspond directly to large-magnitude blade root moment amplitudes. Thus, additional work must be done to quantify the negative turbine response and to correlate this response to turbulent inflow parameters over time scales less than 10 minutes.

Hand, M. M.; Kelley, N. D.; Balas, M. J.

2003-06-01T23:59:59.000Z

270

Airfoil treatments for vertical axis wind turbines  

SciTech Connect

Sandia National Laboratories (SNL) has taken three airfoil related approaches to decreasing the cost of energy of vertical axis wind turbine (VAWT) systems; airfoil sections designed specifically for VAWTs, vortex generators (VGs), and ''pumped spoiling.'' SNL's blade element airfoil section design effort has led to three promising natural laminar flow (NLF) sections. One section is presently being run on the SNL 17-m turbine. Increases in peak efficiency and more desirable dynamic stall regulation characteristics have been observed. Vane-type VGs were fitted on one DOE/Alcoa 100 kW VAWT. With approximately 12% of span having VGs, annual energy production increased by 5%. Pumped spoiling utilizes the centrifugal pumping capabilities of hollow blades. With the addition of small perforations in the surface of the blades and valves controlled by windspeed at the ends of each blade, lift spoiling jets may be generated inducing premature stall and permitting lower capacity, lower cost drivetrain components. SNL has demonstrated this concept on its 5-m turbine and has wind tunnel tested perforation geometries on one NLF section.

Klimas, P.C.

1985-01-01T23:59:59.000Z

271

Wind Turbine Asset Management Technology Assessment  

Science Conference Proceedings (OSTI)

Wind power is one of the fastest growing generation resources in the United States and elsewhere in the world. As of December 2009, the installed wind capacity was more than 35 GW in the United States and more than 160 GW worldwide, and it is forecast to nearly triple to 100 GW and 450 GW, respectively, by 2014. The industry considers the major wind turbine components to be mature commercial technology. However, failures of gearboxes, blades, electrical controls, and other components continue to reduce t...

2010-12-31T23:59:59.000Z

272

Westwind Wind Turbines | Open Energy Information  

Open Energy Info (EERE)

Westwind Wind Turbines Jump to: navigation, search Name Westwind Wind Turbines Place Northern Ireland, United Kingdom Zip BT29 4TF Sector Wind energy Product Northern Ireland based...

273

Root region airfoil for wind turbine  

DOE Patents (OSTI)

A thick airfoil is described for the root region of the blade of a wind turbine. The airfoil has a thickness in a range from 24%--26% and a Reynolds number in a range from 1,000,000 to 1,800,000. The airfoil has a maximum lift coefficient of 1.4--1.6 that has minimum sensitivity to roughness effects. 3 Figs.

Tangler, J.L.; Somers, D.M.

1995-05-23T23:59:59.000Z

274

Howden Wind Turbines Ltd | Open Energy Information  

Open Energy Info (EERE)

Howden Wind Turbines Ltd Jump to: navigation, search Name Howden Wind Turbines Ltd Place United Kingdom Sector Wind energy Product Howden was a manufacturer of wind turbines in the...

275

Using a new characterization of turbulent wind for accurate correlation of wind turbine response with wind speed  

SciTech Connect

The turbulence encountered by a point on a rotating wind turbine blade has characteristics that in some important respects are different from those measured by a stationary anemometer. The conventional one-peaked continuous spectrum becomes, broadly, a two-peaked spectrum that in addition contains a set of narrow-band spikes of turbulence energy, one centered on the frequency of rotor rotation and the others centered on multiples of that frequency. The rotational sampling effect on wind spectra is quantified using measurements of wind velocity by anemometers on stationary crosswind circular arrays. Characteristics of fluctuating wind are compared to measured fluctuations of bending moments of the rotor blades and power output fluctuations of a horizontal-axis wind turbine at the same site. The wind characteristics and the correlations between wind fluctuations and wind turbine fluctuations provide a basis for improving turbine design, siting, and control. 6 refs., 11 figs., 1 tab.

Connell, J.R.; George, R.L.

1987-09-01T23:59:59.000Z

276

Millville Wind Turbine Generator: failure analysis and corrective design modification  

DOE Green Energy (OSTI)

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.

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

1979-07-01T23:59:59.000Z

277

First Hybrid Turbulence Modeling for Turbine Blade Cooling Sagar Kapadia*  

E-Print Network (OSTI)

First Hybrid Turbulence Modeling for Turbine Blade Cooling Sagar Kapadia* and Subrata Roy turbines require proper cooling mechanism to protect the airfoils from thermal stresses generated by exposure to hot combustion gases. The problem becomes aggravated by the growing trend to use higher turbine

Roy, Subrata

278

PowerJet Wind Turbine Project  

SciTech Connect

PROJECT OBJECTIVE The PowerJet wind turbine overcomes problems characteristic of the small wind turbines that are on the market today by providing reliable output at a wide range of wind speeds, durability, silent operation at all wind speeds, and bird-safe operation. Prime Energyâ??s objective for this project was to design and integrate a generator with an electrical controller and mechanical controls to maximize the generation of electricity by its wind turbine. The scope of this project was to design, construct and test a mechanical back plate to control rotational speed in high winds, and an electronic controller to maximize power output and to assist the base plate in controlling rotational speed in high winds. The test model will continue to operate beyond the time frame of the project, with the ultimate goal of manufacturing and marketing the PowerJet worldwide. Increased Understanding of Electronic & Mechanical Controls Integrated With Electricity Generator The PowerJet back plate begins to open as wind speed exceeds 13.5 mps. The pressure inside the turbine and the turbine rotational speed are held constant. Once the back plate has fully opened at approximately 29 mps, the controller begins pulsing back to the generator to limit the rotational speed of the turbine. At a wind speed in excess of 29 mps, the controller shorts the generator and brings the turbine to a complete stop. As the wind speed subsides, the controller releases the turbine and it resumes producing electricity. Data collection and instrumentation problems prevented identification of the exact speeds at which these events occur. However, the turbine, controller and generator survived winds in excess of 36 mps, confirming that the two over-speed controls accomplished their purpose. Technical Effectiveness & Economic Feasibility Maximum Electrical Output The output of electricity is maximized by the integration of an electronic controller and mechanical over-speed controls designed and tested during the course of this project. The output exceeds that of the PowerJetâ??s 3-bladed counterparts (see Appendix). Durability All components of the PowerJet turbine assemblyâ??including the electronic and mechanical controls designed, manufactured and field tested during the course of this projectâ??proved to be durable through severe weather conditions, with constant operation and no interruption in energy production. Low Cost Materials for the turbine, generator, tower, charge controllers and ancillary parts are available at reasonable prices. Fabrication of these parts is also readily available worldwide. The cost of assembling and installing the turbine is reduced because it has fewer parts and requires less labor to manufacture and assemble, making it competitively priced compared with turbines of similar output manufactured in the U.S. and Europe. The electronic controller is the unique part to be included in the turbine package. The controllers can be manufactured in reasonably-sized production runs to keep the cost below $250 each. The data logger and 24 sensors are for research only and will be unnecessary for the commercial product. Benefit To Public The PowerJet wind-electric system is designed for distributed wind generation in 3 and 4 class winds. This wind turbine meets DOEâ??s requirements for a quiet, durable, bird-safe turbine that eventually can be deployed as a grid-connected generator in urban and suburban settings. Results As described more fully below and illustrated in the Appendices, the goals and objectives outlined in 2060 SOPO were fully met. Electronic and mechanical controls were successfully designed, manufactured and integrated with the generator. The turbine, tower, controllers and generators operated without incident throughout the test period, surviving severe winter and summer weather conditions such as extreme temperatures, ice and sustained high winds. The electronic controls were contained in weather-proof electrical boxes and the elec

Bartlett, Raymond J

2008-11-30T23:59:59.000Z

279

NREL: Wind Research - Small Wind Turbine Webinars  

NLE Websites -- All DOE Office Websites (Extended Search)

Small Wind Turbine Webinars Small Wind Turbine Webinars Here you will find webinars about small wind turbines that NREL hosted. Introducing WindLease(tm): Making Wind Energy Affordable NREL and the American Solar Energy Society (ASES) Wind Division co-hosted this webinar. (Text Version.) Date: August 1, 2013 Run Time: 40 minutes Joe Hess, VP of Business Development at United Wind, described United Wind's WindQuote and WindLease Program and explained the process from the dealer's and consumer's perspective. Texas Renewable Energy Industries Association NREL and the American Solar Energy Society (ASES) Wind Division co-hosted this webinar. (Text Version). Date: March 7, 2013 Run Time: 1 hour Russel Smith, Texas Renewable Energy Industries Association executive director and co-founder, provided an overview of the trade association

280

Abstract--Pitch angle control is the most common means for adjusting the aerodynamic torque of the wind turbine when wind  

E-Print Network (OSTI)

of the wind turbine when wind speed is above rated speed and various controlling variables may be chosen Terms--Blade aerodynamic, Fatigue load, Fuzzy logic control, Pitch angle, Wind turbine I. INTRODUCTION of 40 GW. Pitch-adjusting variable-speed wind turbines have become the dominating type of yearly

Hansen, René Rydhof

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281

NREL: Wind Research - Entegrity Wind Systems's EW50 Turbine Testing and  

NLE Websites -- All DOE Office Websites (Extended Search)

Entegrity Wind Systems's EW50 Turbine Testing and Results Entegrity Wind Systems's EW50 Turbine Testing and Results Entegrity Wind Systems' EW50 wind turbine. Text Version As part of the National Renewable Energy Laboratory and U.S. Department of Energy (NREL/DOE) Independent Testing project, NREL tested Entegrity Wind Systems' EW50 turbine at the National Wind Technology Center (NWTC). The EW50 is a 50-kilowatt (kW), three-bladed, horizontal-axis downwind small wind turbine. The turbine's rotor diameter is 15 meters, and its hub height is 30.5 meters. It has a three-phase induction generator that operates at 480 volts AC. Testing Summary The summary of the tests is listed below, along with the final reports. Cumulative Energy Production 3/11/2009: 17; 3/12/2009: 17; 3/13/2009: 17; 3/14/2009: 17; 3/15/2009: 17;

282

Quiet airfoils for small and large wind turbines  

DOE Patents (OSTI)

Thick airfoil families with desirable aerodynamic performance with minimal airfoil induced noise. The airfoil families are suitable for a variety of wind turbine designs and are particularly well-suited for use with horizontal axis wind turbines (HAWTs) with constant or variable speed using pitch and/or stall control. In exemplary embodiments, a first family of three thick airfoils is provided for use with small wind turbines and second family of three thick airfoils is provided for use with very large machines, e.g., an airfoil defined for each of three blade radial stations or blade portions defined along the length of a blade. Each of the families is designed to provide a high maximum lift coefficient or high lift, to exhibit docile stalls, to be relatively insensitive to roughness, and to achieve a low profile drag.

Tangler, James L. (Boulder, CO); Somers, Dan L. (Port Matilda, PA)

2012-06-12T23:59:59.000Z

283

Wind turbine with automatic pitch and yaw control  

DOE Patents (OSTI)

A wind turbine having a flexible central beam member supporting aerodynamic blades at opposite ends thereof and fabricated of uni-directional high tensile strength material bonded together into beam form so that the beam is lightweight, and has high tensile strength to carry the blade centrifugal loads, low shear modulus to permit torsional twisting thereof for turbine speed control purposes, and adequate bending stiffness to permit out-of-plane deflection thereof for turbine yard control purposes. A selectively off-set weighted pendulum member is pivotally connected to the turbine and connected to the beam or blade so as to cause torsional twisting thereof in response to centrifugal loading of the pendulum member for turbine speed control purposes.

Cheney, Jr., Marvin Chapin (Glastonbury, CT); Spierings, Petrus A. M. (Middletown, CT)

1978-01-01T23:59:59.000Z

284

Control of Wind Turbines: Past, Present, and Future  

Science Conference Proceedings (OSTI)

We review the objectives and techniques used in the control of horizontal axis wind turbines at the individual turbine level, where controls are applied to the turbine blade pitch and generator. The turbine system is modeled as a flexible structure operating in the presence of turbulent wind disturbances. Some overview of the various stages of turbine operation and control strategies used to maximize energy capture in below rated wind speeds is given, but emphasis is on control to alleviate loads when the turbine is operating at maximum power. After reviewing basic turbine control objectives, we provide an overview of the common basic linear control approaches and then describe more advanced control architectures and why they may provide significant advantages.

Laks, J. H.; Pao, L. Y.; Wright, A. D.

2009-01-01T23:59:59.000Z

285

Aeroelastic analysis of the troposkien-type wind turbine  

SciTech Connect

The testing of troposkien-type wind turbines has indicated that under certain conditions serious vibrations of the blades can occur, involving flatwise bending, torsion, and chordwise bending. It is the purpose of this report to perform an aeroelastic analysis of the stability of the coupled bending and torsional motion of such blades with a view to determining the cause of these vibrations as a means of suppressing them. The emphasis of the analysis is on obtaining physical understanding rather than exact numerical results. The effect of extreme variation of the chordwise location of the section center of gravity of troposkien-type rotor blades was found to be negligible with regard to blade flutter. This conclusion implies that chordwise mass balancing of the blades is not required, with consequent large reductions in blade design and manufacturing requirements, and therefore in blade cost.

Ham, N.D.

1977-04-01T23:59:59.000Z

286

Turbine blade squealer tip rail with fence members  

Science Conference Proceedings (OSTI)

A turbine blade includes an airfoil, a blade tip section, a squealer tip rail, and a plurality of chordally spaced fence members. The blade tip section includes a blade tip floor located at an end of the airfoil distal from the root. The blade tip floor includes a pressure side and a suction side joined together at chordally spaced apart leading and trailing edges of the airfoil. The squealer tip rail extends radially outwardly from the blade tip floor adjacent to the suction side and extends from a first location adjacent to the airfoil trailing edge to a second location adjacent to the airfoil leading edge. The fence members are located between the airfoil leading and trailing edges and extend radially outwardly from the blade tip floor and axially from the squealer tip rail toward the pressure side.

Little, David A

2012-11-20T23:59:59.000Z

287

Wind turbine generator with improved operating subassemblies  

DOE Patents (OSTI)

A wind turbine includes a yaw spring return assembly to return the nacelle from a position to which it has been rotated by yawing forces, thus preventing excessive twisting of the power cables and control cables. It also includes negative coning restrainers to limit the bending of the flexible arms of the rotor towards the tower, and stop means on the rotor shaft to orient the blades in a vertical position during periods when the unit is upwind when the wind commences. A pendulum pitch control mechanism is improved by orienting the pivot axis for the pendulum arm at an angle to the longitudinal axis of its support arm, and excessive creep is of the synthetic resin flexible beam support for the blades is prevented by a restraining cable which limits the extent of pivoting of the pendulum during normal operation but which will permit further pivoting under abnormal conditions to cause the rotor to stall.

Cheney, Jr., Marvin C. (24 Stonepost Rd., Glastonbury, CT 06033)

1985-01-01T23:59:59.000Z

288

(Construction of a wind turbine). Final report  

Science Conference Proceedings (OSTI)

A wind powered electrical generator was built by industrial arts students working in electricity, woodworking, and metal technology facilities. The blades were originally aluminum frames covered with sailcloth. These were replaced with hand-carved laminated basswood blades. Original plans called for a bullet and downwind propeller, but this was replaced with an upwind propeller and an aft-mounted tailfin. A V-belt and pulley drive transmits power from the turbine and a motorcycle brake stops the machine during high winds and/or for safe servicing. The original 13 volt, 105 amp alternator was replaced by a 12 volt, 100 amp dc generator. Publicity and dissemination events are listed as well as expenditures. (LEW)

Devine, L.E.

1982-03-22T23:59:59.000Z

289

Mitigation of Wind Turbine/Vortex Interaction Using Disturbance Accommodating Control  

DOE Green Energy (OSTI)

Wind turbines, a competitive source of emission-free electricity, are being designed with diameters and hub heights approaching 100 m, to further reduce the cost of the energy they produce. At this height above the ground, the wind turbine is exposed to atmospheric phenomena such as low-level jets, gravity waves, and Kelvin-Helmholtz instabilities, which are not currently modeled in wind turbine design codes. These atmospheric phenomena can generate coherent turbulence that causes high cyclic loads on wind turbine blades. These fluctuating loads lead to fatigue damage accumulation and blade lifetime reduction. Advanced control was used to mitigate vortex-induced blade cyclic loading. A full-state feedback controller that incorporates more detailed vortex inputs achieved significantly greater blade load reduction. Blade loads attributed to vortex passage, then, can be reduced through advanced control, and further reductions appear feasible.

Hand, M. M.

2003-12-01T23:59:59.000Z

290

Applications: Wind turbine structural health  

E-Print Network (OSTI)

of turbine system management. The data obtained from this multi-scale sensing capability will be fullyCapability Applications: Wind turbine structural health monitoring Individual turbine maintenance for active control in the field Limit damage propagation and maintenance costs Maximize return

291

Blade-Vortex Interactions in High Pressure Steam Turbines  

E-Print Network (OSTI)

A detailed experimental and numerical investigation of the transport of streamwise (passage) vortices in high-pressure axial turbines and their interaction with the downstream blade rows was performed. The results indicate large variations in the downstream flow field, notably the development of the secondary flows. The mechanism of passage vortex transport was studied in two differently configured high-pressure turbine stages. In the first configuration, the blades are radially stacked while the second configuration features three-dimensionally stacked high-pressure steam turbine blading. The stator hub passage vortex is chopped by the downstream blade row in a similar way to the wake. The bowed vortex tube near the inlet to the rotor appeared to develop two counter-rotating legs extending back to the leading edges of the adjacent blades. These were termed the suction side leg and the pressure side leg. The two legs of the incoming passage vortex then convect with the respective velocities on the blade surfaces. The results are discussed for the radially stacked turbine and the 3-D turbine separately.

Venkata Siva Prasad Chaluvadi

2000-01-01T23:59:59.000Z

292

Operating Modes of a Teeter-Rotor Wind Turbine  

DOE Green Energy (OSTI)

We examine the operating modes of a two-bladed teetered wind turbine. Because of the gyroscopic asymmetry of its rotor, this turbine's dynamics can be quite distinct from those of a turbine with three or more blades. This asymmetry leads to system equations with periodic coefficients that are solved using the Floquet approach to extract the correct modal parameters. The system equations are derived using a simple analytical model with four degrees of freedom: cacelle yaw, rotor teeter, and flapping associated with each blade. Results confirm that the turbine modes become more dominated by the centrifugal and gyroscopic effects as the rotor speed increases. They gyroscopic effect may also cause dynamic instability. Under certain design conditions, yaw and teeter modal frequencies may coalesce.

Bir, G. S. (National Renewable Energy Laboratory); Stol, K. (University of Colorado at Boulder)

1999-02-25T23:59:59.000Z

293

Wind blade spar cap and method of making  

DOE Patents (OSTI)

A wind blade spar cap for strengthening a wind blade including an integral, unitary three-dimensional woven material having a first end and a second end, corresponding to a root end of the blade and a tip end of the blade, wherein the material tapers in width from the first to the second end while maintaining a constant thickness and decreasing weight therebetween, the cap being capable of being affixed to the blade for providing increased strength with controlled variation in weight from the root end to the tip end based upon the tapered width of the material thereof. The present inventions also include the method of making the wind blade spar cap and a wind blade including the wind blade spar cap.

Mohamed, Mansour H. (Raleigh, NC)

2008-05-27T23:59:59.000Z

294

Flow Integrating Section for a Gas Turbine Engine in Which Turbine Blades are Cooled by Full Compressor Flow  

SciTech Connect

Routing of full compressor flow through hollow turbine blades achieves unusually effective blade cooling and allows a significant increase in turbine inlet gas temperature and, hence, engine efficiency. The invention, ''flow integrating section'' alleviates the turbine dissipation of kinetic energy of air jets leaving the hollow blades as they enter the compressor diffuser.

Steward, W. Gene

1999-11-14T23:59:59.000Z

295

Flow Integrating Section for a Gas Turbine Engine in Which Turbine Blades are Cooled by Full Compressor Flow  

DOE Green Energy (OSTI)

Routing of full compressor flow through hollow turbine blades achieves unusually effective blade cooling and allows a significant increase in turbine inlet gas temperature and, hence, engine efficiency. The invention, ''flow integrating section'' alleviates the turbine dissipation of kinetic energy of air jets leaving the hollow blades as they enter the compressor diffuser.

Steward, W. Gene

1999-11-14T23:59:59.000Z

296

Real-time wind turbine emulator suitable for power quality and dynamic control studies, MASc Thesis  

E-Print Network (OSTI)

Abstract Wind turbines are increasingly becoming significant components of power systems. To evaluate competing wind energy conversion technologies, a real-time Wind Turbine Emulator, which emulates the dynamic torque produced by an actual turbine has been developed. This is necessary since the real world performance of a wind turbine, subjected to variable wind conditions is more difficult to evaluate than a standard turbine generator system operating in near steady state. This emulator is capable of reproducing both the static and dynamic torque of an actual wind turbine. It models the torque oscillations caused by wind shear, tower shadow, and the obvious pulsations caused by variable wind speed. Also included are the dynamic effects of a large turbine inertia. This emulator will allow testing without the costly construction of the actual turbine blades and tower to determine the strengths and weaknesses of competing energy conversion and control technologies.

Dale S. L. Dolan; Student Member; P. W. Lehn; Member Ieee

2005-01-01T23:59:59.000Z

297

NREL: Wind Research - National Wind Technology Center Blade Testing Video  

NLE Websites -- All DOE Office Websites (Extended Search)

Center Blade Testing Video (Text Version) Center Blade Testing Video (Text Version) Below is the text version for the National Wind Technology Center Blade Testing Video. The video opens with the NREL and NWTC logos, surrounded by black screen and including the title: "NWTC Test Facility Introduction, Dr. Fort Felker, Director of the National Wind Technology Center, TRT 1:42, May 29, 2013." Fort Felker is in a yellow helmet and vest, standing in the NWTC's testing facility. There is a railing to his left, construction cones behind him, and a ladder to his right. Fort Felker: "I'm Fort Felker, I'm the director at the Department of Energy's National Wind Technology Center." Fort's name and title cut in on the right. Fort walks toward the camera while talking. Fort Felker: "Here at the NWTC, we have been conducting structural testing

298

Basic Integrative Models for Offshore Wind Turbine Systems  

E-Print Network (OSTI)

This research study developed basic dynamic models that can be used to accurately predict the response behavior of a near-shore wind turbine structure with monopile, suction caisson, or gravity-based foundation systems. The marine soil conditions were modeled using apparent fixity level, Randolph elastic continuum, and modified cone models. The offshore wind turbine structures were developed using a finite element formulation. A two-bladed 3.0 megawatt (MW) and a three-bladed 1.5 MW capacity wind turbine were studied using a variety of design load, and soil conditions scenarios. Aerodynamic thrust loads were estimated using the FAST Software developed by the U.S Department of Energys National Renewable Energy Laboratory (NREL). Hydrodynamic loads were estimated using Morisons equation and the more recent Faltinsen Newman Vinje (FNV) theory. This research study addressed two of the important design constraints, specifically, the angle of the support structure at seafloor and the horizontal displacement at the hub elevation during dynamic loading. The simulation results show that the modified cone model is stiffer than the apparent fixity level and Randolph elastic continuum models. The effect of the blade pitch failure on the offshore wind turbine structure decreases with increasing water depth, but increases with increasing hub height of the offshore wind turbine structure.

Aljeeran, Fares

2011-05-01T23:59:59.000Z

299

Plasma Aerodynamic Control Effectors for Improved Wind Turbine Performance  

DOE Green Energy (OSTI)

Orbital Research Inc is developing an innovative Plasma Aerodynamic Control Effectors (PACE) technology for improved performance of wind turbines. The PACE system is aimed towards the design of "smart" rotor blades to enhance energy capture and reduce aerodynamic loading and noise using flow-control. The PACE system will provide ability to change aerodynamic loads and pitch distribution across the wind turbine blade without any moving surfaces. Additional benefits of the PACE system include reduced blade structure weight and complexity that should translate into a substantially reduced initial cost. During the Phase I program, the ORI-UND Team demonstrated (proof-of-concept) performance improvements on select rotor blade designs using PACE concepts. Control of both 2-D and 3-D flows were demonstrated. An analytical study was conducted to estimate control requirements for the PACE system to maintain control during wind gusts. Finally, independent laboratory experiments were conducted to identify promising dielectric materials for the plasma actuator, and to examine environmental effects (water and dust) on the plasma actuator operation. The proposed PACE system will be capable of capturing additional energy, and reducing aerodynamic loading and noise on wind turbines. Supplementary benefits from the PACE system include reduced blade structure weight and complexity that translates into reduced initial capital costs.

Mehul P. Patel; Srikanth Vasudevan; Robert C. Nelson; Thomas C. Corke

2008-08-01T23:59:59.000Z

300

On the impact of variability and assembly on turbine blade cooling flow and oxidation life  

E-Print Network (OSTI)

The life of a turbine blade is dependent on the quantity and temperature of the cooling flow sup- plied to the blade. The focus of this thesis is the impact of variability on blade cooling flow and, subsequently, its impact ...

Sidwell, Carroll Vincent, 1972-

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Evolution of Turbine Blade Deposits in an Accelerated Deposition Facility: Roughness and Thermal Analysis.  

E-Print Network (OSTI)

??During the operation of a gas turbine, ingested contaminants present in the air form deposits on the surfaces of the turbine blades. These deposits grow (more)

Wammack, James Edward 1979-

2005-01-01T23:59:59.000Z

302

The Production of Advanced Turbine Blades from P/M Superalloy ...  

Science Conference Proceedings (OSTI)

Introduction. The continual increase in the severity of gas turbine operating conditions has led to a progressive replacement of forged turbine blades from the first.

303

Experimental evaluation and modeling of a turbine blade with potassium evaporative cooling  

E-Print Network (OSTI)

A new method of turbine blade cooling, the Return Flow Cascade, has been developed in which vaporization of a liquid metal such as potassium is used to maintain the blade surface at a nearly uniform temperature. Turbine ...

Townsend, Jessica Lee

2004-01-01T23:59:59.000Z

304

Impact of aerothermal modeling on the estimation of turbine blade life  

E-Print Network (OSTI)

The impact of aerothermal modeling on estimates of turbine blade heat transfer and life was assessed for three high pressure turbine blades. The work was conducted as part of a project aimed at the evaluation of the effect ...

Collin, Jean E., 1978-

2004-01-01T23:59:59.000Z

305

Adaptive pitch control for variable speed wind turbines  

DOE Patents (OSTI)

An adaptive method for adjusting blade pitch angle, and controllers implementing such a method, for achieving higher power coefficients. Average power coefficients are determined for first and second periods of operation for the wind turbine. When the average power coefficient for the second time period is larger than for the first, a pitch increment, which may be generated based on the power coefficients, is added (or the sign is retained) to the nominal pitch angle value for the wind turbine. When the average power coefficient for the second time period is less than for the first, the pitch increment is subtracted (or the sign is changed). A control signal is generated based on the adapted pitch angle value and sent to blade pitch actuators that act to change the pitch angle of the wind turbine to the new or modified pitch angle setting, and this process is iteratively performed.

Johnson, Kathryn E. (Boulder, CO); Fingersh, Lee Jay (Westminster, CO)

2012-05-08T23:59:59.000Z

306

Probabilistic fatigue methodology and wind turbine reliability  

DOE Green Energy (OSTI)

Wind turbines subjected to highly irregular loadings due to wind, gravity, and gyroscopic effects are especially vulnerable to fatigue damage. The objective of this study is to develop and illustrate methods for the probabilistic analysis and design of fatigue-sensitive wind turbine components. A computer program (CYCLES) that estimates fatigue reliability of structural and mechanical components has been developed. A FORM/SORM analysis is used to compute failure probabilities and importance factors of the random variables. The limit state equation includes uncertainty in environmental loading, gross structural response, and local fatigue properties. Several techniques are shown to better study fatigue loads data. Common one-parameter models, such as the Rayleigh and exponential models are shown to produce dramatically different estimates of load distributions and fatigue damage. Improved fits may be achieved with the two-parameter Weibull model. High b values require better modeling of relatively large stress ranges; this is effectively done by matching at least two moments (Weibull) and better by matching still higher moments. For this purpose, a new, four-moment {open_quotes}generalized Weibull{close_quotes} model is introduced. Load and resistance factor design (LRFD) methodology for design against fatigue is proposed and demonstrated using data from two horizontal-axis wind turbines. To estimate fatigue damage, wind turbine blade loads have been represented by their first three statistical moments across a range of wind conditions. Based on the moments {mu}{sub 1}{hor_ellipsis}{mu}{sub 3}, new {open_quotes}quadratic Weibull{close_quotes} load distribution models are introduced. The fatigue reliability is found to be notably affected by the choice of load distribution model.

Lange, C.H. [Stanford Univ., CA (United States)

1996-05-01T23:59:59.000Z

307

Parametric design of floating wind turbines  

E-Print Network (OSTI)

As the price of energy increases and wind turbine technology matures, it is evident that cost effective designs for floating wind turbines are needed. The next frontier for wind power is the ocean, yet development in near ...

Tracy, Christopher (Christopher Henry)

2007-01-01T23:59:59.000Z

308

SMI 2012: Full Paper: Medial design of blades for hydroelectric turbines and ship propellers  

Science Conference Proceedings (OSTI)

We present a method for constructing blades of hydroelectric turbines and ship propellers based on design parameters that possess a clear hydraulic meaning. The design process corresponds to the classical construction of a blade using the medial surface ... Keywords: B-spline representation, CAD-model, Hydroelectric turbine blade, Medial axis-based design, Propeller blade

M. Rossgatterer; B. Jttler; M. Kapl; G. Della Vecchia

2012-08-01T23:59:59.000Z

309

Development of a Wave Energy -Responsive Self-Actuated Blade Articulation Mechanism for an OWC Turbine  

SciTech Connect

The Phase I SBIR effort completed the feasibility design, fabrication, and wind tunnel testing of a self-actuated blade articulation mechanism that uses a torsion bar and a lightweight airfoil to affect the articulation of the Wells airfoil. The articulation is affected only by the air stream incident on the airfoil. The self-actuating blade eliminates the complex and costly linkage mechanism that is now needed to perform this function on either a variable pitch Wells-type or Dennis-Auld air turbine. Using the results reported by independent researchers, the projected improvement in the Wells-type turbine efficiency is 20-40%, in addition to an increase in the operating air flow range by 50-100%, therefore enabling a smaller or slower single turbine to be used.

Francis A. Di Bella

2010-06-01T23:59:59.000Z

310

Advanced multistage turbine blade aerodynamics, performance, cooling, and heat transfer  

DOE Green Energy (OSTI)

The gas turbine has the potential for power production at the highest possible efficiency. The challenge is to ensure that gas turbines operate at the optimum efficiency so as to use the least fuel and produce minimum emissions. A key component to meeting this challenge is the turbine. Turbine performance, both aerodynamics and heat transfer, is one of the barrier advanced gas turbine development technologies. This is a result of the complex, highly three-dimensional and unsteady flow phenomena in the turbine. Improved turbine aerodynamic performance has been achieved with three-dimensional highly-loaded airfoil designs, accomplished utilizing Euler or Navier-Stokes Computational Fluid Dynamics (CFD) codes. These design codes consider steady flow through isolated blade rows. Thus they do not account for unsteady flow effects. However, unsteady flow effects have a significant impact on performance. Also, CFD codes predict the complete flow field. The experimental verification of these codes has traditionally been accomplished with point data - not corresponding plane field measurements. Thus, although advanced CFD predictions of the highly complex and three-dimensional turbine flow fields are available, corresponding data are not. To improve the design capability for high temperature turbines, a detailed understanding of the highly unsteady and three-dimensional flow through multi-stage turbines is necessary. Thus, unique data are required which quantify the unsteady three-dimensional flow through multi-stage turbine blade rows, including the effect of the film coolant flow. Also, as design CFD codes do not account for unsteady flow effects, the next logical challenge and the current thrust in CFD code development is multiple-stage analyses that account for the interactions between neighboring blade rows. Again, to verify and or direct the development of these advanced codes, complete three-dimensional unsteady flow field data are needed.

Fleeter, S.; Lawless, P.B. [Purdue Univ., West Lafayette, IN (United States). School of Mechanical Engineering

1995-12-31T23:59:59.000Z

311

Onshore Wind Turbines Life Extension  

Science Conference Proceedings (OSTI)

Wind turbines are currently type-certified for nominal 20-year design lives, but many wind industry stakeholders are considering the possibility of extending the operating lives of their projects by 5, 10, or 15 years. Life extensionthe operation of an asset beyond the nominal design lifeis just one option to maximize the financial return of these expensive assets. Other options include repowering, upgrading, or uprating a turbine.In order to make informed decisions ...

2012-10-01T23:59:59.000Z

312

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network (OSTI)

3.2.1 Description of Test Wind Turbine . . . . . .Figure 1.2: Components of a modern wind turbine . . . . . .Wind Turbine . . . . . . . . . . . . . . . . . . . . . . .

Prowell, I.

2011-01-01T23:59:59.000Z

313

Gamesa Wind Turbines Pvt Ltd | Open Energy Information  

Open Energy Info (EERE)

Turbines Pvt Ltd Jump to: navigation, search Name Gamesa Wind Turbines Pvt. Ltd. Place Chennai, Tamil Nadu, India Sector Wind energy Product Chennai-based wind turbine...

314

NREL Innovations Contribute to an Award-Winning Small Wind Turbine (Fact Sheet)  

DOE Green Energy (OSTI)

The Skystream 3.7 wind turbine is the result of a decade-long collaboration between the National Renewable Energy Laboratory (NREL) and Southwest Windpower, a commercially successful small wind turbine manufacturer. NREL drew heavily on its research experience to incorporate innovations into the Skystream 3.7, including a unique blade design that makes the wind turbine more efficient and quieter than most.

Not Available

2010-12-01T23:59:59.000Z

315

Addendum to a proposal to NSF to sponsor a vertical-axis wind turbine research program  

SciTech Connect

Information is presented concerning the performance evaluation of a 15 foot-diameter test bed Darrieus rotor, Darrieus rotor wind tunnel tests, Savonius rotor wind tunnel tests, blade manufacturing techniques for 15 foot-diameter and 35 foot-diameter wind turbines, static and dynamic structural analysis, production prototype design of a 15 foot-diameter turbine, production prototype design of 35 foot-diameter turbine, and aerodynamic performance studies.

Blackwell, B.F.; Feltz, L.V.; Rightley, E.C.

1974-11-01T23:59:59.000Z

316

Wind turbine aerodynamics using ALE---VMS: validation and the role of weakly enforced boundary conditions  

Science Conference Proceedings (OSTI)

In this article we present a validation study involving the full-scale NREL Phase VI two-bladed wind turbine rotor. The ALE---VMS formulation of aerodynamics, based on the Navier---Stokes equations of incompressible flows, is employed in conjunction ... Keywords: ALE---VMS, Finite elements, NREL 5MW offshore, NREL Phase VI, Weakly enforced essential boundary conditions, Wind turbine aerodynamics

Ming-Chen Hsu; Ido Akkerman; Yuri Bazilevs

2012-10-01T23:59:59.000Z

317

High Temperature Capabililty and Innovative Cooling with a Spar and Shell Turbine Blade - Florida Turbine Technologies  

NLE Websites -- All DOE Office Websites (Extended Search)

Temperature Capability and Temperature Capability and Innovative Cooling with a Spar and Shell Turbine Blade-Florida Turbine Technologies Background Florida Turbine Technologies, Inc. (FTT) is currently developing advanced aerothermal technologies centered on spar and shell airfoil concepts meant to provide highly durable turbine components that require the lowest cooling flow possible. The spar-shell system represents a unique opportunity for the use of advanced, high-temperature materials

318

NREL: Wind Research - Small Wind Turbine Independent Testing  

NLE Websites -- All DOE Office Websites (Extended Search)

Wind Research Search More Search Options Site Map Printable Version Small Wind Turbine Independent Testing One of the barriers for the small wind market has been the lack...

319

Gas Turbine Superalloy Material Property Handbook for Blades  

Science Conference Proceedings (OSTI)

Published material property data on superalloy bucket (blade) materials used in land-based combustion turbines is meager and widely scattered in literature. This handbook provides a comprehensive resource of material property data for superalloys used in combustion turbine buckets. Such data are critical for use in remaining life assessment calculations, failure analysis, comparison of various alloys, and alloy selection. The material data presented in this handbook were developed from experimental alloy...

2003-07-18T23:59:59.000Z

320

Energy 101: Wind Turbines | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Wind Turbines Wind Turbines Energy 101: Wind Turbines Addthis Description See how wind turbines generate clean electricity from the power of the wind. Highlighted are the various parts and mechanisms of a modern wind turbine. Duration 2:16 Topic Tax Credits, Rebates, Savings Wind Energy Economy Credit Energy Department Video MR. : We've all seen those creaky old windmills on farms, and although they may seem about as low-tech as you can get, those old windmills are the predecessors for new modern wind turbines that generate electricity. The same wind that used to pump water for cattle is now turning giant wind turbines to power cities and homes. OK, have a look at this wind farm in the California desert, a hot desert next to tall mountains - an ideal place for a lot of wind.

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES  

E-Print Network (OSTI)

APPENDIX A MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES #12;A-1 APPENDIX A MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES 1.0 INTRODUCTION Differential composition of wind turbines at wind energy used is the number of fatalities per wind turbine per year (Anderson et al. 1999). This metric has

322

A Dynamic Wind Turbine Simulator of the Wind Turbine Generator System  

Science Conference Proceedings (OSTI)

To study dynamic performances of wind turbine generator system (WTGS), and to determine the control structures in laboratory. The dynamic torque generated by wind turbine (WT) must be simulated. In there paper, a dynamic wind turbine emulator (WTE) is ... Keywords: dynamic wind turbine emulation, wind shear, tower shadow, torque compensation

Lei Lu; Zhen Xie; Xing Zhang; Shuying Yang; Renxian Cao

2012-01-01T23:59:59.000Z

323

Vertical axis wind turbine power regulation through centrifugally pumped lift spoiling  

Science Conference Proceedings (OSTI)

This paper describes an approach for lowering the rated windspeeds of Darrieus-type vertical axis wind turbines (VAWTs) whose blades are hollow aluminum extrusions. The blades, which when rotating act as centrifugal pumps, are fitted with a series of small perforations distributed along a portion of the blades' span. By valving the ends of the hollow blades, flow into the blade ends and out of the perforations may be controlled. This flow can induce premature aerodynamic stall on the blade elements, thereby reducing both the rated power of the turbine and its cost-of-energy. The concept has been proven on the Sandia National Laboratories 5-m diameter research VAWT and force balance and flow visualization wind tunnel tests have been conducted using a blade section designed for the VAWT application.

Klimas, P.C.; Sladky, J.F. Jr.

1985-01-01T23:59:59.000Z

324

Offshore Wind Turbines and Their Installation  

Science Conference Proceedings (OSTI)

Offshore winds tend to be higher, more constant and not disturbed by rough terrain, so there is a large potential for utilizing wind energy near to the sea. Compared with the wind energy converters onland, wind turbine components offshore will subject ... Keywords: renewable energy, wind power generation, offshore wind turbines, offshore installation

Liwei Li; Jianxing Ren

2010-01-01T23:59:59.000Z

325

Wind Turbines Electrical and Mechanical Engineering  

E-Print Network (OSTI)

Wind Turbines Electrical and Mechanical Engineering Objective · Introduce students to the concept of alternative energy. · Explain the math and scientific principles behind engineering wind turbines. Standards and how it applies to wind energy · About how surface area and shape effects wind turbine efficiency

Provancher, William

326

Energy 101: Wind Turbines | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Wind Turbines Wind Turbines Energy 101: Wind Turbines Addthis Below is the text version for the Energy 101: Wind Turbines video. The video opens with "Energy 101: Wind Turbines." This is followed by wooden windmills on farms. We've all seen those creaky, old windmills on farms. And although they may seem about as low-tech as you can get, those old windmills are the predecessors for new, modern wind turbines that generat electricity. The video pans through shots of large windmills and wind farms of different sizes, situated on cultivated plains and hills. The same wind that used to pump water for cattle is now turning giant wind turbines to power cities and homes. OK, have a look at this wind farm in the California desert. A hot desert, next to tall mountains. An ideal place for a lot of wind.

327

Maglev Wind Turbine Technologies | Open Energy Information  

Open Energy Info (EERE)

Maglev Wind Turbine Technologies Maglev Wind Turbine Technologies Jump to: navigation, search Name Maglev Wind Turbine Technologies Place Sierra Vista, Arizona Zip 85635 Sector Wind energy Product The new company employs magnetic levitation (Maglev) technology in its wind turbines, which it says will have a longer life span, be cheaper to build, and produce 1GW of energy each. References Maglev Wind Turbine Technologies[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Maglev Wind Turbine Technologies is a company located in Sierra Vista, Arizona . References ↑ "Maglev Wind Turbine Technologies" Retrieved from "http://en.openei.org/w/index.php?title=Maglev_Wind_Turbine_Technologies&oldid=348578"

328

Review of wind simulation methods for horizontal-axis wind turbine analysis  

DOE Green Energy (OSTI)

This report reviews three reports on simulation of winds for use in wind turbine fatigue analysis. The three reports are presumed to represent the state of the art. The Purdue and Sandia methods simulate correlated wind data at two points rotating as on the rotor of a horizontal-axis wind turbine. The PNL method at present simulates only one point, which rotates either as on a horizontal-axis wind turbine blade or as on a vertical-axis wind turbine blade. The spectra of simulated data are presented from the Sandia and PNL models under comparable input conditions, and the energy calculated in the rotational spikes in the spectra by the two models is compared. Although agreement between the two methods is not impressive at this time, improvement of the Sandia and PNL methods is recommended as the best way to advance the state of the art. Physical deficiencies of the models are cited in the report and technical recommendations are made for improvement. The report also reviews two general methods for simulating single-point data, called the harmonic method and the white noise method. The harmonic method, which is the basis of all three specific methods reviewed, is recommended over the white noise method in simulating winds for wind turbine analysis.

Powell, D.C.; Connell, J.R.

1986-06-01T23:59:59.000Z

329

Virtual Wind Speed Sensor for Wind Turbines Andrew Kusiak1  

E-Print Network (OSTI)

Virtual Wind Speed Sensor for Wind Turbines Andrew Kusiak1 ; Haiyang Zheng2 ; and Zijun Zhang3 Abstract: A data-driven approach for development of a virtual wind-speed sensor for wind turbines is presented. The virtual wind-speed sensor is built from historical wind-farm data by data-mining algorithms

Kusiak, Andrew

330

NREL: Wind Research - Advanced Research Turbines  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Turbines Two 440 foot meteorological towers are upwind of two research wind turbines. Two 600-kW Westinghouse turbines at the NWTC are used to test new control...

331

Wind and solar powered turbine  

SciTech Connect

A power generating station having a generator driven by solar heat assisted ambient wind is disclosed. A first plurality of radially extending air passages direct ambient wind to a radial flow wind turbine disposed in a centrally located opening in a substantially disc-shaped structure. A solar radiation collecting surface having black bodies is disposed above the first plurality of air passages and in communication with a second plurality of radial air passages. A cover plate enclosing the second plurality of radial air passages is transparent so as to permit solar radiation to effectively reach the black bodies. The second plurality of air passages direct ambient wind and thermal updrafts generated by the black bodies to an axial flow turbine which also derives additional motive power from the air mass exhausted by the radial flow turbine. The rotating shaft of the turbines drive the generator. The solar and wind driven power generating system operates in electrical cogeneration mode with a fuel powered prime mover. The system is particularly adapted to satisfy the power requirements of a relatively small community located in a geographic area having favorable climatic conditions for wind and solar powered power generation.

Wells, I.D.; Holmes, M.; Kohn, J.L.

1984-02-28T23:59:59.000Z

332

Vertical axis wind turbine airfoil  

DOE Patents (OSTI)

A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

2012-12-18T23:59:59.000Z

333

Coupled Dynamic Analysis of Multiple Unit Floating Offshore Wind Turbine  

E-Print Network (OSTI)

In the present study, a numerical simulation tool has been developed for the rotor-floater-tether coupled dynamic analysis of Multiple Unit Floating Offshore Wind Turbine (MUFOWT) in the time domain including aero-blade-tower dynamics and control, mooring dynamics and platform motion. In particular, the numerical tool developed in this study is based on the single turbine analysis tool FAST, which was developed by National Renewable Energy Laboratory (NREL). For linear or nonlinear hydrodynamics of floating platform and generalized-coordinate-based FEM mooring line dynamics, CHARM3D program, hull-riser-mooring coupled dynamics program developed by Prof. M.H. Kims research group during the past two decades, is incorporated. So, the entire dynamic behavior of floating offshore wind turbine can be obtained by coupled FAST-CHARM3D in the time domain. During the coupling procedure, FAST calculates all the dynamics and control of tower and wind turbine including the platform itself, and CHARM3D feeds all the relevant forces on the platform into FAST. Then FAST computes the whole dynamics of wind turbine using the forces from CHARM3D and return the updated displacements and velocities of the platform to CHARM3D. To analyze the dynamics of MUFOWT, the coupled FAST-CHARM3D is expanded more and re-designed. The global matrix that includes one floating platform and a number of turbines is built at each time step of the simulation, and solved to obtain the entire degrees of freedom of the system. The developed MUFOWT analysis tool is able to compute any type of floating platform with various kinds of horizontal axis wind turbines (HAWT). Individual control of each turbine is also available and the different structural properties of tower and blades can be applied. The coupled dynamic analysis for the three-turbine MUFOWT and five-turbine MUFOWT are carried out and the performances of each turbine and floating platform in normal operational condition are assessed. To investigate the coupling effect between platform and each turbine, one turbine failure event is simulated and checked. The analysis shows that some of the mal-function of one turbine in MUFOWT may induce significant changes in the performance of other turbines or floating platform. The present approach can directly be applied to the development of the remote structural health monitoring system of MUFOWT in detecting partial turbine failure by measuring tower or platform responses in the future.

Bae, Yoon Hyeok

2013-05-01T23:59:59.000Z

334

A Summary of the Fatigue Properties of Wind Turbine Materials  

DOE Green Energy (OSTI)

Modern wind turbines are fatigue critical machines that are typically used to produce electrical power from the wind. The materials used to construct these machines are subjected to a unique loading spectrum that contains several orders of magnitude more cycles than other fatigue critical structures, e.g., an airplane. To facilitate fatigue designs, a large database of material properties has been generated over the past several years that is specialized to materials typically used in wind turbines. In this paper, I review these fatigue data. Major sections are devoted to the properties developed for wood, metals (primarily aluminum) and fiberglass. Special emphasis is placed on the fiberglass discussion because this material is current the material of choice for wind turbine blades. The paper focuses on the data developed in the U.S., but cites European references that provide important insights.

SUTHERLAND, HERBERT J.

1999-10-07T23:59:59.000Z

335

Wind Turbine Productivity Improvement and Procurement Guidelines  

Science Conference Proceedings (OSTI)

Proper selection of equipment specifications during wind turbine procurement and careful operation and maintenance procedures are keys to maximizing wind project availability and annual energy generation and revenues.

2002-03-28T23:59:59.000Z

336

SUSTAINABLE CONCRETE FOR WIND TURBINE FOUNDATIONS.  

SciTech Connect

The use of wind power to generate electricity continues to grow, especially given commitments by various countries throughout the world to ensure that a significant percentage of energy comes from renewable sources. In order to meet such objectives, increasingly larger turbines with higher capacity are being developed. The engineering aspects of larger turbine development tend to focus on design and materials for blades and towers. However, foundations are also a critical component of large wind turbines and represent a significant cost of wind energy projects. Ongoing wind research at BNL is examining two areas: (a) structural response analysis of wind turbine-tower-foundation systems and (b) materials engineering of foundations. This work is investigating the dynamic interactions in wind turbine systems, which in turn assists the wind industry in achieving improved reliability and more cost efficient foundation designs. The results reported herein cover initial studies of concrete mix designs for large wind turbine foundations and how these may be tailored to reduce cost and incorporate sustainability and life cycle concepts. The approach taken was to investigate material substitutions so that the environmental, energy and CO{sub 2}-impact of concrete could be reduced. The use of high volumes of ''waste'' materials in concrete was examined. These materials included fly ash, blast furnace slag and recycled concrete aggregate. In addition, the use of steel fiber reinforcement as a means to improve mechanical properties and potentially reduce the amount of bar reinforcement in concrete foundations was studied. Four basic mixes were considered. These were: (1) conventional mix with no material substitutions, (2) 50% replacement of cement with fly ash, (3) 50% replacement of cement with blast furnace slag and (4) 25% replacement of cement with fly ash and 25% replacement with blast furnace slag. Variations on these mixes included the addition of 1% by volume steel fibers. The use of recycled concrete aggregate in the conventional and 50% slag mixes was also studied. Properties investigated included compressive and tensile strengths, elastic modulus, coefficient of permeability, thermal conductivity and durability in seawater and sulfate solutions. It was determined that the mixes containing 50% slag gave the best overall performance. Slag was particularly beneficial for concrete that used recycled aggregate and could reduce strength losses. Initial durability results indicated that corrosion of fibers in the different concrete mixes when exposed to seawater was minimal. Future research needs to include more detailed studies of mix design and properties of concrete for wind turbine foundations. Emphasis on slag-modified mixes with natural and recycled concrete aggregate is recommended. The proportion of slag that can be incorporated in the concrete needs to be optimized, as does the grading of recycled aggregate. The potential for using silica fume in conjunction with slag is worth exploring as this may further enhance strength and durability. Longer-term durability studies are necessary and other pertinent properties of concrete that require investigation include damping characteristics, pullout strength, fatigue strength and risk of thermal cracking. The properties of sustainable concrete mixes need to be integrated with studies on the structural behavior of wind turbine foundations in order to determine the optimal mix design and to examine means of reducing conservatism and cost of foundations.

BERNDT,M.L.

2004-06-01T23:59:59.000Z

337

Verification of creep performance of a ceramic gas turbine blade  

SciTech Connect

Tensile creep tests were carried out on a Norton NT164 silicon nitride ceramic turbine blade containing 4 wt. % Y{sub 2}O{sub 3} sintering additive at 1,370 C in air under selected stress levels. The objective of this study was to measure the creep properties of test specimens extracted from a complex shaped ceramic gas turbine blade to verify the response of actual components. The creep results indicated that specimens from both the airfoil and dovetail sections exhibited creep rates that were about 4 to 100 times higher than those obtained from both the buttonhead and dogbone creep specimens machined from the developmental billets fabricated with the same composition and processing procedures. Electron microscopy analyses suggested that high creep rates and short lifetimes observed in specimens extracted from the turbine blade resulted from a higher glassy phase(s) content and smaller number density of elongated grain microstructure. Silicon nitride ceramics with an in-situ reinforced elongated microstructure have been the primary candidates for both advanced automotive and land-based gas turbine engine applications.

Lin, H.T.; Becher, P.F.; Ferber, M.K. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Parthasarathy, V. [Solar Turbines Inc., San Diego, CA (United States)

1998-03-01T23:59:59.000Z

338

Offshore Wind Turbines: Some Technical Challenges  

E-Print Network (OSTI)

1 Offshore Wind Turbines: Some Technical Challenges Prof. Guy Houlsby FREng Oxford University House engineers concerned with installation of offshore wind turbines. The author is Professor of Civil solved, a DTI and EPSRC-sponsored research programme on foundations for wind turbines will be briefly

Houlsby, Guy T.

339

AWEA Small Wind Turbine Global Market Study  

E-Print Network (OSTI)

wind turbines ­ those with rated capacities of 100 kilowatts (kW)1 and less ­ grew 15% in 2009 with 20 small wind turbines, 95 of which-- more than one-third--are based in the u.S. An estimated 100,000 unitsAWEA Small Wind Turbine Global Market Study YEAR ENDING 2009 #12;Summary 3 Survey Findings

Leu, Tzong-Shyng "Jeremy"

340

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network (OSTI)

the passing wind. The blade pitch is continuously adjustedconditions as it has a ?xed blade pitch and is designed todue to the variation in the blade pitch. As the wind speed

Prowell, I.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Condition Monitoring of Wind Turbines  

Science Conference Proceedings (OSTI)

Based on industry experience, after four years of operation, failures of wind turbine gearboxes, generators, and other major components become common, and each failure typically requires major repairs and/or component replacement. Wind project owners and operators who apply lube oil monitoring, vibration-signature analysis, and other condition monitoring technology can expect to detect subtle changes in machine condition that often lead to major failures if left unrepaired. The estimated cost savings of ...

2006-03-27T23:59:59.000Z

342

NREL: Wind Research - Case Study: Burke Mountain Wind Turbine...  

NLE Websites -- All DOE Office Websites (Extended Search)

composting program, and encouraging visitors to recycle whenever possible. Wind Powering America verified the following wind turbine project facts with Hannah Collins from...

343

Vertical axis wind turbine development. Final report, March 1, 1976-June 30, 1977  

DOE Green Energy (OSTI)

Theoretical and experimental research accomplished in evaluating an innovative concept for vertical axis wind turbines (VAWT) is described. The concept is that of using straight blades composed of circulation controlled airfoil sections. The theoretical analysis has been developed to determine the unsteady lift and moment characteristics of multiple-blade cross-flow wind turbines. To determine the drag data needed as input to the theoretical analysis, an outdoor test model VAWT has been constructed; design details, instrumentation, calibration results, and initial test results are reported. Initial testing was with fixed pitch blades having cross-sections of conventional symmetrical airfoils. Costs of building the test model are included, as well as cost estimates for blades constructed with composite materials. These costs are compared with those of other types of wind turbines.

Walters, R. E.; Fanucci, J. B.; Hill, P. W.; Migliore, P. G.

1979-07-01T23:59:59.000Z

344

Blade Manufacturing Improvement Project: Final Report  

SciTech Connect

The Blade Manufacturing Improvement Project explores new, unique and improved materials integrated with innovative manufacturing techniques that promise substantial economic enhancements for the fabrication of wind turbine blades. The primary objectives promote the development of advanced wind turbine blade manufacturing in ways that lower blade costs, cut rotor weight, reduce turbine maintenance costs, improve overall turbine quality and increase ongoing production reliability. Foam Matrix (FMI) has developed a wind turbine blade with an engineered foam core, incorporating advanced composite materials and using Resin Transfer Molding (RTM) processes to form a monolithic blade structure incorporating a single molding tool. Patented techniques are employed to increase blade load bearing capability and insure the uniform quality of the manufactured blade. In production quantities, FMI manufacturing innovations may return a sizable per blade cost reduction when compared to the cost of producing comparable blades with conventional methods.

SHERWOOD, KENT

2002-10-01T23:59:59.000Z

345

Small Wind Turbine Testing and Applications Development  

Science Conference Proceedings (OSTI)

Small wind turbines offer a promising alternative for many remote electrical uses where there is a good wind resource. The National Wind Technology Center (NWTC) of the National Renewable Energy Laboratory helps further the role that small turbines can play in supplying remote power needs. The NWTC tests and develops new applications for small turbines. The NWTC also develops components used in conjunction with wind turbines for various applications. This paper describes wind energy research at the NWTC for applications including battery charging stations, water desalination/purification, and health clinics. Development of data acquisition systems and tests on small turbines are also described.

Corbus, D.; Baring-Gould, I.; Drouilhet, S.; Gevorgian, V.; Jimenez, T.; Newcomb, C.; Flowers, L.

1999-09-14T23:59:59.000Z

346

Steam as turbine blade coolant: Experimental data generation  

DOE Green Energy (OSTI)

Steam as a coolant is a possible option to cool blades in high temperature gas turbines; however there is practically no experimental data. This work deals with an attempt to generate such data and with the design of an experimental setup used for the purpose. Initially, in order to guide the direction of experiments, a preliminary theoretical and empirical prediction of the expected experimental data is performed and is presented here. This initial analysis also compares the coolant properties of steam and air.

Wilmsen, B.; Engeda, A.; Lloyd, J.R. [Michigan State Univ., East Lansing, MI (United States). Dept. of Mechanical Engineering

1995-12-31T23:59:59.000Z

347

Isogeometric Simulation of Turbine Blades for Aircraft Engines David Gromann1  

E-Print Network (OSTI)

Isogeometric Simulation of Turbine Blades for Aircraft Engines David Gro?mann1 , Bert Jüttler2, in the challenging field of aircraft engines. We study the deformation of turbine blades under the assumption, manufacturing and repairing turbine engines for aircrafts. A challenging task in this field is the efficient

Jüttler, Bert

348

Alternative Design Study Report: WindPACT Advanced Wind Turbine Drive Train Designs Study; November 1, 2000 -- February 28, 2002  

DOE Green Energy (OSTI)

This report presents the Phase I results of the National Renewable Energy Laboratory's (NREL's) WindPACT (Wind Partnership for Advanced Component Technologies) Advanced Wind Turbine Drive Train Designs Study. Global Energy Concepts, LLC performed this work under a subcontract with NREL. The purpose of the WindPACT project is to identify technology improvements that will enable the cost of energy (COE) from wind turbines to be reduced. Other parts of the WindPACT project have examined blade and logistics scaling, balance-of-station costs, and rotor design. This study was designed to investigate innovative drive train designs.

Poore, R.; Lettenmaier, T.

2003-08-01T23:59:59.000Z

349

Full-scale wind turbine rotor aerodynamics research  

DOE Green Energy (OSTI)

The United States Department of Energy and the National Renewable Energy Laboratory (NREL) are conducting research to improve wind turbine technology at the NREL National Wind Technology Center (NWTC). One program, the Combined Experiment, has focused on making measurements needed to understand aerodynamic and structural responses of horizontal-axis wind turbines (HAWT). A new phase of this program, the Unsteady Aerodynamics Experiment, will focus on quantifying unsteady aerodynamic phenomena prevalent in stall-controlled HAWTs. Optimally twisted blades and innovative instrumentation and data acquisition systems will be used in these tests. Data can now be acquired and viewed interactively during turbine operations. This paper describes the NREL Unsteady Aerodynamics Experiment and highlights planned future research activities.

Simms, D A; Butterfield, C P

1994-11-01T23:59:59.000Z

350

Fatigue reliability of wind turbine components  

DOE Green Energy (OSTI)

Fatigue life estimates for wind turbine components can be extremely variable due to both inherently random and uncertain parameters. A structural reliability analysis is used to qualify the probability that the fatigue life will fall short of a selected target. Reliability analysis also produces measures of the relative importance of the various sources of uncertainty and the sensitivity of the reliability to each input parameter. The process of obtaining reliability estimates is briefly outlined. An example fatigue reliability calculation for a blade joint is formulated; reliability estimates, importance factors, and sensitivities are produced. Guidance in selecting distribution functions for the random variables used to model the random and uncertain parameters is also provided. 5 refs., 9 figs., 1 tab.

Veers, P.S.

1990-01-01T23:59:59.000Z

351

Stakeholder Engagement and Outreach: Siting Wind Turbines  

Wind Powering America (EERE)

Resources & Tools Resources & Tools Siting Wind Turbines Wind Powering America works to increase deployment of wind energy. This page provides resources about wind turbine siting. American Wind Wildlife Institute The American Wind Wildlife Institute (AWWI) facilitates timely and responsible development of wind energy, while protecting wildlife and wildlife habitat. AWWI was created and is sustained by a unique collaboration of environmentalists, conservationists, state wildlife agencies, and wind industry leaders. Its purpose is to help lay the scientific groundwork and best practices for wind farm siting and operations, through targeted initiatives: wind-wildlife research, landscape assessment, mitigation, and education. Ordinances Regulating Development of Commercial Wind Energy Facilities

352

Model for simulating rotational data for wind turbine applications  

DOE Green Energy (OSTI)

This document describes a wind simulation model to be used in relation to wind turbine operations. The model is a computer code written in FORTRAN 77. The model simulates turbulence and mean wind effects as they are experienced at a rotating point on the blade of either a horizontal-axis wind turbine (HAWT) or a vertical-axis wind turbine (VAWT). The model is fast, requiring 15 to 120 seconds of VAX execution time to produce a simulation and related statistics. The model allows the user to set a number of wind parameters so that he may evaluate the uncertainty of model results as well as their typical values. When this capability is combined with short execution time, the user can quickly produce a number of simulations based on reasonable variation of input parameters and can use these simulations to obtain a range of wind turbine responses to the turbulence. This ability is important because some of the wind parameters that cannot be precisely evaluated should be prescribed over a range of values. This document is essentially a user's guide. Its features include theoretical derivations, samples of output, comparisons of measured and modeled results, a listing of the FORTRAN code, a glossary for the code, and the input and output of a sample run.

Powell, D.C.; Connell, J.R.

1986-04-01T23:59:59.000Z

353

Further investigations of diffuser augmented wind turbines. Part 2. Technical report. Final report  

DOE Green Energy (OSTI)

A multiphased investigation is described which involves three test facilities of several compact diffuser approaches. Screens, to simulate a wind turbine, and a three-bladed, fixed-pitch turbine have been with the diffuser models. A candidate baseline design is described and some of the key issues are discussed that can lead to future full scale implementation.

Foreman, K.M.; Gilbert, B.L.

1979-07-01T23:59:59.000Z

354

Definition: Wind turbine | Open Energy Information  

Open Energy Info (EERE)

turbine turbine Jump to: navigation, search Dictionary.png Wind turbine A machine that converts wind energy to mechanical energy; typically connected to a generator to produce electricity.[1][2] View on Wikipedia Wikipedia Definition A wind turbine is a device that converts kinetic energy from the wind, also called wind energy, into mechanical energy in a process known as wind power. If the mechanical energy is used to produce electricity, the device may be called a wind turbine or wind power plant. If the mechanical energy is used to drive machinery, such as for grinding grain or pumping water, the device is called a windmill or wind pump. Similarly, it may be referred to as a wind charger when used for charging batteries. The result of over a millennium of windmill development and modern engineering,

355

Method and apparatus for wind turbine air gap control - Energy ...  

Methods and apparatus for assembling a wind turbine generator are provided. The wind turbine generator includes a core and a plurality of stator windings ...

356

Fish Passage Assessment of an Advanced Hydropower Turbine and Conventional Turbine Using Blade-strike Modeling  

Science Conference Proceedings (OSTI)

In the Columbia and Snake River basins, several species of Pacific salmon were listed under the Endangered Species Act of 1973 due to significant declines of fish population. Dam operators and design engineers are thus faced with the task of making those hydroelectric facilities more ecologically friendly through changes in hydro-turbine design and operation. Public Utility District No. 2 of Grant County, Washington, applied for re-licensing from the U.S. Federal Energy Regulatory Commission to replace the 10 turbines at Wanapum Dam with advanced hydropower turbines that were designed to increase power generation and improve fish passage conditions. We applied both deterministic and stochastic blade-strike models to the newly installed turbine and an existing turbine. Modeled probabilities were compared to the results of a large-scale live fish survival study and a sensor fish study under the same operational parameters. Overall, injury rates predicted by the deterministic model were higher than experimental rates of injury while those predicted by the stochastic model were in close agreement with experiment results. Fish orientation at the time of entry into the plane of the leading edges of the turbine runner blades was an important factor contributing to uncertainty in modeled results. The advanced design turbine had slightly higher modeled injury rates than the existing turbine design; however, there was no statistical evidence that suggested significant differences in blade-strike injuries between the two turbines and the hypothesis that direct fish survival rate through the advanced hydropower turbine is equal or better than that through the conventional turbine could not be rejected.

Deng, Zhiqun; Carlson, Thomas J.; Dauble, Dennis D.; Ploskey, Gene R.

2011-01-04T23:59:59.000Z

357

Pitch Angle Control of Variable Low Rated Speed Wind Turbine Using Fuzzy Logic Control  

E-Print Network (OSTI)

Abstract Pitch angle control of wind turbine has been used widely to reduce torque and output power variation in high rated wind speed areas. It is a challenge to maximize available energy in the low rated wind speed areas. In this paper, a wind turbine prototype with a pitch angle control based on fuzzy logic to maximize the output power is built and demonstrated. In the varying low rated wind speed of 4-6 m/s, the use of fuzzy logic controller can maximize the average output power of 14.5 watt compared to 14.0 watt at a fixed pitch angle of the blade. Implementation of pitch angle fuzzy logic-based control to the wind turbine is suitable for the low rated wind speed areas. Index Terms low rated wind speed areas, pitch angle control, fuzzy logic, wind turbine. T I.

A. Musyafa; A. Harika; I. M. Y. Negara; I. Rob

2010-01-01T23:59:59.000Z

358

Parametric Study of Turbine Blade Internal Cooling and Film Cooling  

E-Print Network (OSTI)

Gas turbine engines are extensively used in the aviation and power generation industries. They are used as topping cycles in combined cycle power plants, or as stand alone power generation units. Gains in thermodynamic efficiency can be realized by increasing the turbine inlet temperatures. Since modern turbine inlet temperatures exceed the melting point of the constituent superalloys, it is necessary to provide an aggressive cooling system. Relatively cool air, ducted from the compressor of the engine is used to remove heat from the hot turbine blade. This air flows through passages in the hollow blade (internal cooling), and is also ejected onto the surface of the blade to form an insulating film (film cooling). Modern land-based gas turbine engines use high Reynolds number internal flow to cool their internal passages. The first part of this study focuses on experiments pertaining to passages with Reynolds numbers of up to 400,000. Common turbulator designs (45degree parallel sharp-edged and round-edged) ribs are studied. Older correlations are found to require corrections in order to be valid in the high Reynolds number parameter space. The effect of rotation on heat transfer in a typical three-pass serpentine channel is studied using a computational model with near-wall refinement. Results from this computational study indicate that the hub experiences abnormally high heat transfer under rotation. An experimental study is conducted at Buoyancy numbers similar to an actual engine on a wedge shaped model trailing edge, roughened with pin-fins and equipped with slot ejection. Results show an asymmetery between the leading and trailing surfaces due to rotation - a difference which is subdued due to the provision of pin-fins. Film cooling effectiveness is measured by the PSP mass transfer analogy technique in two different configurations: a flat plate and a typical high pressure turbine blade. Parameters studied include a step immediately upstream of a row of holes; the Strouhal number (quantifying rotor-stator interaction) and coolant to mainstream density ratio. Results show a deterioration in film cooling effectiveness with on increasing the Strouhal number. Using a coolant with a higher density results in higher film cooling effectiveness.

Rallabandi, Akhilesh P.

2010-08-01T23:59:59.000Z

359

Smart Sensor System for Structural Condition Monitoring of Wind Turbines: 30 May 2002--30 April 2006  

DOE Green Energy (OSTI)

This report describes the efforts of the University of Cincinnati, North Carolina A&T State University, and NREL to develop a structural neural system for structural health monitoring of wind turbine blades.

Schulz, M. J.; Sundaresan, M. J.

2006-08-01T23:59:59.000Z

360

Chapter 14: Wind Turbine Control Systems  

DOE Green Energy (OSTI)

Wind turbines are complex, nonlinear, dynamic systems forced by gravity, stochastic wind disturbances, and gravitational, centrifugal, and gyroscopic loads. The aerodynamic behavior of wind turbines is nonlinear, unsteady, and complex. Turbine rotors are subjected to a complicated three-dimensional turbulent wind inflow field that drives fatigue loading. Wind turbine modeling is also complex and challenging. Accurate models must contain many degrees of freedom (DOF) to capture the most important dynamic effects. The rotation of the rotor adds complexity to the dynamics modeling. Designs of control algorithms for wind turbines must account for these complexities. Algorithms must capture the most important turbine dynamics without being too complex and unwieldy. Off-the-shelf commercial soft ware is seldom adequate for wind turbine dynamics modeling. Instead, specialized dynamic simulation codes are usually required to model all the important nonlinear effects. As illustrated in Figure 14-1, a wind turbine control system consists of sensors, actuators and a system that ties these elements together. A hardware or software system processes input signals from the sensors and generates output signals for actuators. The main goal of the controller is to modify the operating states of the turbine to maintain safe turbine operation, maximize power, mitigate damaging fatigue loads, and detect fault conditions. A supervisory control system starts and stops the machine, yaws the turbine when there is a significant yaw misalignment, detects fault conditions, and performs emergency shut-downs. Other parts of the controller are intended to maximize power and reduce loads during normal turbine operation.

Wright, A. D.

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Evaluation of the Distortion of a Hydro Turbine Blade during Heat ...  

Science Conference Proceedings (OSTI)

Presentation Title, Evaluation of the Distortion of a Hydro Turbine Blade during Heat Treatment Process. Author(s), Jinwu Kang. On-Site Speaker (Planned)...

362

Wind turbine generators having wind assisted cooling systems and cooling methods  

DOE Patents (OSTI)

A wind generator includes: a nacelle; a hub carried by the nacelle and including at least a pair of wind turbine blades; and an electricity producing generator including a stator and a rotor carried by the nacelle. The rotor is connected to the hub and rotatable in response to wind acting on the blades to rotate the rotor relative to the stator to generate electricity. A cooling system is carried by the nacelle and includes at least one ambient air inlet port opening through a surface of the nacelle downstream of the hub and blades, and a duct for flowing air from the inlet port in a generally upstream direction toward the hub and in cooling relation to the stator.

Bagepalli, Bharat (Niskayuna, NY); Barnes, Gary R. (Delanson, NY); Gadre, Aniruddha D. (Rexford, NY); Jansen, Patrick L. (Scotia, NY); Bouchard, Jr., Charles G. (Schenectady, NY); Jarczynski, Emil D. (Scotia, NY); Garg, Jivtesh (Cambridge, MA)

2008-09-23T23:59:59.000Z

363

Energy 101: Wind Turbines | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Wind Turbines Wind Turbines Energy 101: Wind Turbines July 30, 2010 - 10:47am Addthis John Schueler John Schueler Former New Media Specialist, Office of Public Affairs On Tuesday, the Department announced a $117 million loan guarantee through for the Kahuku Wind Power Project in Hawaii. That's a major step forward for clean energy in the region, as it's expected to supply clean electricity to roughly 7,700 households per year, and it also invites a deceptively simple question: how exactly do wind turbines generate electricity? One thing you might not realize is that wind is actually a form of solar energy. This is because wind is produced by the sun heating Earth's atmosphere, the rotation of the earth, and the earth's surface irregularities. Wind turbines are the rotary devices that convert the

364

Offshore Wind Turbine Wakes Measured by Sodar  

Science Conference Proceedings (OSTI)

A ship-mounted sodar was used to measure wind turbine wakes in an offshore wind farm in Denmark. The wake magnitude and vertical extent were determined by measuring the wind speed profile behind an operating turbine, then shutting down the ...

R. J. Barthelmie; L. Folkerts; F. T. Ormel; P. Sanderhoff; P. J. Eecen; O. Stobbe; N. M. Nielsen

2003-04-01T23:59:59.000Z

365

NREL: Wind Research - Mariah Power's Windspire Wind Turbine Testing and  

NLE Websites -- All DOE Office Websites (Extended Search)

Mariah Power's Windspire Wind Turbine Testing and Results Mariah Power's Windspire Wind Turbine Testing and Results A video of Mariah Power's Windspire wind turbine. Text Version As part of the National Renewable Energy Laboratory and U.S. Department of Energy (NREL/DOE) Independent Testing project, NREL tested Mariah Power's Windspire Giromill small wind turbine at the National Wind Technology Center (NWTC) through January 14, 2009 when NREL terminated its testing. Read a chronology of events and letter from Mariah Power to NREL. The Windspire is a 1.2-kilowatt (kW) vertical-axis small wind turbine. The turbine tower is 9.1 meters tall, and its rotor area is 1.2 by 6.1 meters. The turbine has a permanent-magnet generator with a single-phase output at 120 volts AC. Testing Summary Testing was terminated January 14, 2009. Published test reports include

366

Assessment of research needs for wind turbine rotor materials technology  

DOE Green Energy (OSTI)

Wind-driven power systems is a renewable energy technology that is still in the early stages of development. Wind power plants installed in early 1980s suffered structural failures chiefly because of incomplete understanding of wind forces (turbulent), in some cases because of poor product quality. Failures of rotor blades are now somewhat better understood. This committee has examined the experience base accumulated by wind turbines and the R and D programs sponsored by DOE. It is concluded that a wind energy system such as is described is within the capability of engineering practice; however because of certain gaps in knowledge, and the presence of only one major integrated manufacturer of wind power machines in the USA, a DOE R and D investment is still required.

Not Available

1991-01-01T23:59:59.000Z

367

Segmented and self-adjusting wind turbine rotors. Final report  

DOE Green Energy (OSTI)

An investigation was carried out to examine the use of blade aeroelastic properties for providing rotational speed control for a wind turbine generator (WTG). The study was specifically directed at obtaining a rotor configuration that has the capability for maintaining nearly constant torque at constant RPM in the presence of varying wind conditions and is aimed at eliminating the current requirement for mechanical pitch change devices. The approach considered is one in which rotor twist due to aerodynamic loading is used to adjust the blade's pitch as the wind speed changes. The preliminary design concept that has evolved is a flexible rotor blade formed from a series of individual, light, rigid segments that are arranged along the blade spar. Each segment can rotate around the spar but is restricted in pitch by a nonlinear mechanical spring. The results of performance calculations as well as vibration and flutter analyses are presented. Based on these results, the concept appears to provide an attractive solution to the problem of WTG operation in a varying wind field.

Jordan, P.F.; Goldman, R.L.

1976-04-01T23:59:59.000Z

368

Offshore Wind Turbines Estimated Noise from Offshore Wind Turbine, Monhegan Island, Maine Addendum 2  

SciTech Connect

Additional modeling for offshore wind turbines, for proposed floating wind platforms to be deployed by University of Maine/DeepCwind.

Aker, Pamela M.; Jones, Anthony M.; Copping, Andrea E.

2011-03-01T23:59:59.000Z

369

Small Wind Research Turbine: Final Report  

DOE Green Energy (OSTI)

The Small Wind Research Turbine (SWRT) project was initiated to provide reliable test data for model validation of furling wind turbines and to help understand small wind turbine loads. This report will familiarize the user with the scope of the SWRT test and support the use of these data. In addition to describing all the testing details and results, the report presents an analysis of the test data and compares the SWRT test data to simulation results from the FAST aeroelastic simulation model.

Corbus, D.; Meadors, M.

2005-10-01T23:59:59.000Z

370

Stakeholder Engagement and Outreach: Wind Turbine Ordinances  

Wind Powering America (EERE)

Information Information Resources Printable Version Bookmark and Share Publications Success Stories Webinars Podcasts Videos Stakeholder Interviews Lessons Learned Wind Working Groups Economic Impact Studies Wind Turbine Ordinances Wind Turbine Ordinances This page lists 135 state and local wind turbine ordinances. State and local governments and policymakers can use this collection of example wind turbine ordinances when drafting a new wind energy ordinance in a town or county without existing ordinances. Due to increasing energy demands in the United States and more installed wind projects, rural communities and local governments with limited or no experience with wind energy now have the opportunity to become involved in this industry. Communities with good wind resources may be approached by

371

Blade Testing at NREL's National Wind Technology Center (NWTC) (Presentation)  

SciTech Connect

Presentation of Blade Testing at NREL's National Wind Technology Center for the 2010 Sandia National Laboratories Blade Testing Workshop.

Hughes, S.

2010-07-20T23:59:59.000Z

372

Wind Turbine Design Innovations Drive Industry Transformation...  

NLE Websites -- All DOE Office Websites (Extended Search)

Wind Turbine Design Innovations Drive Industry Transformation For more than 20 years, the National Renewable Energy Laboratory (NREL) has helped GE and its predecessors achieve...

373

Improving Wind Turbine Gearbox Reliability: Preprint  

DOE Green Energy (OSTI)

This paper describes a new research and development initiative to improve gearbox reliability in wind turbines begun at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, USA.

Musial, W.; Butterfield, S.; McNiff, B.

2007-06-01T23:59:59.000Z

374

THE ENERGY BALANCE OF MODERN WIND TURBINES  

E-Print Network (OSTI)

A modern Danish 600 kW wind turbine will recover all the energy spent in its manufacture, maintenance, and scrapping within some three months of its commissioning.

unknown authors

1997-01-01T23:59:59.000Z

375

Modelling and control of large wind turbine.  

E-Print Network (OSTI)

?? In order to make the wind energy an economical alternative for energy production, upscaling of turbine to 10 - 15MW may be necessary to (more)

zafar, syed hammad

2013-01-01T23:59:59.000Z

376

Wind Turbine Generator System Safety and Function Test Report for the Entegrity EW50 Wind Turbine  

DOE Green Energy (OSTI)

This report summarizes the results of a safety and function test that NREL conducted on the Entegrity EW50 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

Smith, J.; Huskey, A.; Jager, D.; Hur, J.

2012-11-01T23:59:59.000Z

377

Wind Turbine Generator System Safety and Function Test Report for the Ventera VT10 Wind Turbine  

DOE Green Energy (OSTI)

This report summarizes the results of a safety and function test that NREL conducted on the Ventera VT10 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

Smith, J.; Huskey, A.; Jager, D.; Hur, J.

2012-11-01T23:59:59.000Z

378

Stability analysis of a variable-speed wind turbine  

DOE Green Energy (OSTI)

This paper examines the elastomechanical stability of a four-bladed wind turbine over a specific rotor speed range. Stability modes, frequencies, and dampings are extracted using a specialized modal processor developed at NREL that post-processes the response data generated by the ADAMS simulation code. The processor can analyze a turbine with an arbitrary number of rotor blades and offers a novel capability of isolating stability modes that become locked at a single frequency. Results indicate that over a certain rotor speed range, the tower lateral mode and the rotor regressive in-plane mode coalesce, resulting in a self-excited instability. Additional results show the effect of tower and nacelle parameters on the stability boundaries.

Bir, G.S.; Wright, A.D.; Butterfield, C.P.

1996-10-01T23:59:59.000Z

379

Deposition of Graded Thermal Barrier Coatings for Gas Turbine ...  

Wind Energy Industrial Technologies Advanced Materials Deposition of Graded Thermal Barrier Coatings for Gas Turbine Blades Sandia National ...

380

NREL: Technology Transfer - CRADA Opportunity for Blade ...  

... seeks one or more CRADA partners to develop testing technologies and equipment for static and fatigue testing of wind turbine blades up to ...

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network (OSTI)

Utility Scale Wind Turbine, with a preliminary author lista Utility Scale Wind Turbine with a preliminary author listUtility Scale Wind Turbine Including Operational E?ects with a preliminary author list

Prowell, I.

2011-01-01T23:59:59.000Z

382

Dynamic analysis of a 5 megawatt offshore floating wind turbine  

E-Print Network (OSTI)

1985. 23. Hau, E. Wind Turbines: Fundamentals, Technologies,for Floating Offshore Wind Turbines. Tech. no. NREL/CP-500-Full-scale Floating Wind Turbine." Statoil, 14 Oct. 2009.

Harriger, Evan Michael

2011-01-01T23:59:59.000Z

383

Understanding Trends in Wind Turbine Prices Over the Past Decade  

E-Print Network (OSTI)

Bloomberg NEF). 2011c. Wind Turbine Price Index, Issue V.Hand, A. Laxson. 2006. Wind Turbine Design Cost and Scalingof a Multi-MegaWatt Wind Turbine. Renewable Energy, vol.

Bolinger, Mark

2012-01-01T23:59:59.000Z

384

Wind turbine trailing-edge aerodynamic brake design  

DOE Green Energy (OSTI)

This report describes the design of a centrifugally actuated aerodynamic-overspeed device for a horizontal-axis wind turbine. The device will meet the following criteria; (1) It will be effective for airfoil angles of attack 0{degrees} to 45{degrees}. (2) It will be stowed inside the blade profile prior to deployment. (3) It will be capable of offsetting the positive torque produced by the overall blade. (4) Hinge moments will be minimized to lower actuator loads and cost. (5) It will be evaluated as a potential power modulating active rotor-control system. A literature review of aerodynamic braking devices was conducted. Information from the literature review was used to conceptualize the most effective devices for subsequent testing and design. Wind-tunnel test data for several braking devices are presented in this report. Using the data for the most promising configuration, a preliminary design was developed for a MICON 65/13 wind turbine with Phoenix 7.9-m rotor blades.

Quandt, G.

1996-01-01T23:59:59.000Z

385

NREL: Wind Research - Testing  

NLE Websites -- All DOE Office Websites (Extended Search)

Testing Photo of a large wind turbine blade sticking out of the structural testing laboratory; it is perpendicular to a building at the National Wind Technology Center. A...

386

Siting technologies for large wind turbine clusters  

DOE Green Energy (OSTI)

Site selection for large wind turbine clusters requires thorough documentation of the wind characteristics at the site, because of the influence these characteristics will have on the economics, operations, and service life of the wind turbines. The wind prospecting strategy can be used by a utility to determine specific locations for each wind turbine in a cluster of 10 to 50 or more machines. The key to site selection is knowing what and where to measure. Siting techniques to be used at the various stages of the wind-prospecting strategy are discussed. These techniques help determine where to measure. What to measure at a site is still a moot question. Suggestions are made on what data are needed at what sampling rates. These are based on the assumption that until further experience in siting large clusters of wind turbines is in hand, thorough documentation of wind characteristics affecting machine and cluster output characteristics, operation strategies, and service life are necessary.

Hiester, T.R.; Pennell, W.T.

1979-11-01T23:59:59.000Z

387

Ceramic blade attachment system  

SciTech Connect

A retainer ring is arranged to mount turbine blades to a turbine disk so that aerodynamic forces produced by a gas turbine engine are transferred from the turbine blades to the turbine disk to cause the turbine blades and turbine disk to rotate, but so that centrifugal forces of the turbine blades resulting from the rotation of the turbine blades and turbine disk are not transferred from the turbine blades to the turbine disk.

Boyd, Gary L. (Alpine, CA)

1995-01-01T23:59:59.000Z

388

Ceramic blade attachment system  

DOE Patents (OSTI)

A retainer ring is arranged to mount turbine blades to a turbine disk so that aerodynamic forces produced by a gas turbine engine are transferred from the turbine blades to the turbine disk to cause the turbine blades and turbine disk to rotate, but so that centrifugal forces of the turbine blades resulting from the rotation of the turbine blades and turbine disk are not transferred from the turbine blades to the turbine disk. 6 figures.

Boyd, G.L.

1995-04-11T23:59:59.000Z

389

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network (OSTI)

2.2.1 Turbine Description . . . . . . . . . . . . . . . . .112 4.2 Description of Turbine . . . . . . . . . . . . . . .3.2.1 Description of Test Wind Turbine . . . . . .

Prowell, I.

2011-01-01T23:59:59.000Z

390

Proceedings: Workshop on Corrosion of Steam Turbine Blading and Disks in the Phase Transition Zone  

Science Conference Proceedings (OSTI)

Most outage hours for steam turbines are due to corrosion of low pressure (LP) blades and disks in the phase transition zone (PTZ). EPRI's Workshop on Corrosion of Steam Turbine Blading and Disks in the PTZ critically reviewed the state of knowledge of corrosion fatigue and stress corrosion cracking of LP blade and disk materials, with particular emphasis on the influence of the local environment.

1998-12-17T23:59:59.000Z

391

IC-EpsMsO NUMERICAL SIMULATION IN VERTICAL WIND AXIS TURBINE WITH PITCH  

E-Print Network (OSTI)

energy, pitch controlled blades Abstract: Wind energy is more and more used as a renewable energy source character. The present wind turbine is a small one which allows to be used on roofs or in gardens to light small areas like publicity boards, parking, roads or for water pumping, heating... The present turbine has a vertical axis. Each turbine blade combines a rotating movement around its own axis and around the main rotor axis. Due to this combination of movements, flow around this turbine is highly unsteady and needs to be modeled by unsteady calculation. One of the main problems of such geometry is to simulate the two combined movements. The present work is an extended study of ones made in 2009. In the previous study, some results like contours of pressure and velocity fields were presented for elliptic blades for one specific constant rotational speed and benefits of combined rotating blades was shown. The present paper points up the influence of two different blades geometries for different rotational speeds, different blade stagger angles and different Reynolds numbers related to a wider range of wind speeds. 1

Controlled Blades; Bayeul-lain Annie-claude; Dockter Aurore; Bois Grard; Simonet Sophie

2013-01-01T23:59:59.000Z

392

An examination of loads and responses of a wind turbine undergoing variable-speed operation  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory has recently developed the ability to predict turbine loads and responses for machines undergoing variable-speed operation. The wind industry has debated the potential benefits of operating wind turbine sat variable speeds for some time. Turbine system dynamic responses (structural response, resonance, and component interactions) are an important consideration for variable-speed operation of wind turbines. The authors have implemented simple, variable-speed control algorithms for both the FAST and ADAMS dynamics codes. The control algorithm is a simple one, allowing the turbine to track the optimum power coefficient (C{sub p}). The objective of this paper is to show turbine loads and responses for a particular two-bladed, teetering-hub, downwind turbine undergoing variable-speed operation. The authors examined the response of the machine to various turbulent wind inflow conditions. In addition, they compare the structural responses under fixed-speed and variable-speed operation. For this paper, they restrict their comparisons to those wind-speed ranges for which limiting power by some additional control strategy (blade pitch or aileron control, for example) is not necessary. The objective here is to develop a basic understanding of the differences in loads and responses between the fixed-speed and variable-speed operation of this wind turbine configuration.

Wright, A.D.; Buhl, M.L. Jr.; Bir, G.S.

1996-11-01T23:59:59.000Z

393

DEVELOPMENT OF PROTECTIVE COATINGS FOR SINGLE CRYSTAL TURBINE BLADES  

DOE Green Energy (OSTI)

Turbine blades in coal derived syngas systems are subject to oxidation and corrosion due to high steam temperature and pressure. Thermal barrier coatings (TBCs) are developed to address these problems. The emphasis is on prime-reliant design and a better coating architecture, having high temperature and corrosion resistance properties for turbine blades. In Phase I, UES Inc. proposed to develop, characterize and optimize a prime reliant TBC system, having smooth and defect-free NiCoCrAlY bond layer and a defect free oxide sublayer, using a filtered arc technology. Phase I work demonstrated the deposition of highly dense, smooth and defect free NiCoCrAlY bond coat on a single crystal CMSX-4 substrate and the deposition of alpha-alumina and yttrium aluminum garnet (YAG) sublayer on top of the bond coat. Isothermal and cyclic oxidation test and pre- and post-characterization of these layers, in Phase I work, (with and without top TBC layer of commercial EB PVD YSZ) revealed significant performance enhancement.

Amarendra K. Rai

2006-12-04T23:59:59.000Z

394

Experimental investigation of film cooling effectiveness on gas turbine blades  

E-Print Network (OSTI)

The hot gas temperature in gas turbine engines is far above the permissible metal temperatures. Advanced cooling technologies must be applied to cool the blades, so they can withstand the extreme conditions. Film cooling is widely used in modern high temperature and high pressure blades as an active cooling scheme. In this study, the film cooling effectiveness in different regions of gas turbine blades was investigated with various film hole/slot configurations and mainstream flow conditions. The study consisted of four parts: 1) effect of upstream wake on blade surface film cooling, 2) effect of upstream vortex on platform purge flow cooling, 3) influence of hole shape and angle on leading edge film cooling and 4) slot film cooling on trailing edge. Pressure sensitive paint (PSP) technique was used to get the conduction-free film cooling effectiveness distribution. For the blade surface film cooling, the effectiveness from axial shaped holes and compound angle shaped holes were examined. Results showed that the compound angle shaped holes offer better film effectiveness than the axial shaped holes. The upstream stationary wakes have detrimental effect on film effectiveness in certain wake rod phase positions. For platform purge flow cooling, the stator-rotor gap was simulated by a typical labyrinth-like seal. Delta wings were used to generate vortex and modeled the passage vortex generated by the upstream vanes. Results showed that the upstream vortex reduces the film cooling effectiveness on the platform. For the leading edge film cooling, two film cooling designs, each with four film cooling hole configurations, were investigated. Results showed that the shaped holes provide higher film cooling effectiveness than the cylindrical holes at higher average blowing ratios. In the same range of average blowing ratio, the radial angle holes produce better effectiveness than the compound angle holes. The seven-row design results in much higher effectiveness than the three-row design. For the trailing edge slot cooling, the effect of slot lip thickness on film effectiveness under the two mainstream conditions was investigated. Results showed thinner lips offer higher effectiveness. The film effectiveness on the slots reduces when the incoming mainstream boundary layer thickness decreases.

Gao, Zhihong

2007-08-01T23:59:59.000Z

395

Experiences with titanium next-to-last LP blades in a 1300 MW turbine  

SciTech Connect

The use of titanium as a material for the end blades of LP turbines has already been investigated twenty years ago by Brown Boveri. Next-to-last LP blades in the past have several times been the cause of turbine damage, because these blades work in the zone of the first condensation and thus are subjected to mechanical stress in corrosive environment. Favorable corrosion properties of titanium provided a reason for developing and manufacturing two next-to-last titanium low pressure blade rows in 1980 and to use them in a 1300 MW plant. On the occasion of an overhaul, a visual check was carried out of the titanium blades and chemical analysis of the blade surface deposits were made. From the distribution of the deposits conclusions can be drawn, retroactively, as to why steel blades might have failed. The titanium blades are undergoing a further operation period.

Meyer, H.W.

1982-01-01T23:59:59.000Z

396

Wind Turbine Generator System Power Performance Test Report for the ARE442 Wind Turbine  

DOE Green Energy (OSTI)

This report summarizes the results of a power performance test that NREL conducted on the ARE 442 wind turbine. This test was conducted in accordance with the International Electrotechnical Commission's (IEC) standard, Wind Turbine Generator Systems Part 12: Power Performance Measurements of Electricity Producing Wind Turbines, IEC 61400-12-1 Ed.1.0, 2005-12. However, because the ARE 442 is a small turbine as defined by IEC, NREL also followed Annex H that applies to small wind turbines. In these summary results, wind speed is normalized to sea-level air density.

van Dam, J.; Jager, D.

2010-02-01T23:59:59.000Z

397

Mixer-Ejector Wind Turbine: Breakthrough High Efficiency Shrouded Wind Turbine  

SciTech Connect

Broad Funding Opportunity Announcement Project: FloDesign Wind Turbines innovative wind turbine, inspired by the design of jet engines, could deliver 300% more power than existing wind turbines of the same rotor diameter by extracting more energy over a larger area. FloDesign Wind Turbines unique shrouded design expands the wind capture area, and the mixing vortex downstream allows more energy to flow through the rotor without stalling the turbine. The unique rotor and shrouded design also provide significant opportunity for mass production and simplified assembly, enabling mid-scale turbines (approximately 100 kW) to produce power at a cost that is comparable to larger-scale conventional turbines.

None

2010-02-22T23:59:59.000Z

398

NREL: Wind Research - Small Wind Turbine Tests and Testing Approach  

NLE Websites -- All DOE Office Websites (Extended Search)

Association of Laboratory Accreditation (A2LA). The suite of tests conducted on small wind turbines includes acoustic noise emissions, duration, power performance, power...

399

EA-1923: Green Energy School Wind Turbine Project on Saipan,...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3: Green Energy School Wind Turbine Project on Saipan, Commonwealth of the Northern Mariana Islands EA-1923: Green Energy School Wind Turbine Project on Saipan, Commonwealth of the...

400

Lattice Tower Design of Offshore Wind Turbine Support Structures.  

E-Print Network (OSTI)

??Optimal design of support structure including foundation and turbine tower is among the most critical challenges for offshore wind turbine. With development of offshore wind (more)

Gong, W.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Use of SCADA Data for Failure Detection in Wind Turbines  

SciTech Connect

This paper discusses the use of existing wind turbine SCADA data for development of fault detection and diagnostic techniques for wind turbines.

Kim, K.; Parthasarathy, G.; Uluyol, O.; Foslien, W.; Sheng, S.; Fleming, P.

2011-10-01T23:59:59.000Z

402

Wind Turbine Generator Condition Monitoring via the Generator Control Loop.  

E-Print Network (OSTI)

??This thesis focuses on the development of condition monitoring techniques for application in wind turbines, particularly for offshore wind turbine driven doubly fed induction generators. (more)

ZAGGOUT, MAHMOUD,NOUH

2013-01-01T23:59:59.000Z

403

UMore Park Wind Turbine Project Loggerhead Shrike Survey, DOE...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

UMore Park Wind Turbine Project Loggerhead Shrike Survey, DOEEA-1791 (June 2010) UMore Park Wind Turbine Project Loggerhead Shrike Survey, DOEEA-1791 (June 2010) The project area...

404

Combined Experiment Phase 1. [Horizontal axis wind turbines: wind tunnel testing versus field testing  

DOE Green Energy (OSTI)

How does wind tunnel airfoil data differ from the airfoil performance on an operating horizontal axis wind turbine (HAWT) The National Renewable Energy laboratory has been conducting a comprehensive test program focused on answering this question and understanding the basic fluid mechanics of rotating HAWT stall aerodynamics. The basic approach was to instrument a wind rotor, using an airfoil that was well documented by wind tunnel tests, and measure operating pressure distributions on the rotating blade. Based an the integrated values of the pressure data, airfoil performance coefficients were obtained, and comparisons were made between the rotating data and the wind tunnel data. Care was taken to the aerodynamic and geometric differences between the rotating and the wind tunnel models. This is the first of two reports describing the Combined Experiment Program and its results. This Phase I report covers background information such as test setup and instrumentation. It also includes wind tunnel test results and roughness testing.

Butterfield, C.P.; Musial, W.P.; Simms, D.A.

1992-10-01T23:59:59.000Z

405

Data Analytics Methods in Wind Turbine Design and Operations  

E-Print Network (OSTI)

This dissertation develops sophisticated data analytic methods to analyze structural loads on, and power generation of, wind turbines. Wind turbines, which convert the kinetic energy in wind into electrical power, are operated within stochastic environments. To account for the influence of environmental factors, we employ a conditional approach by modeling the expectation or distribution of response of interest, be it the structural load or power output, conditional on a set of environmental factors. Because of the different nature associated with the two types of responses, our methods also come in different forms, conducted through two studies. The first study presents a Bayesian parametric model for the purpose of estimating the extreme load on a wind turbine. The extreme load is the highest stress level that the turbine structure would experience during its service lifetime. A wind turbine should be designed to resist such a high load to avoid catastrophic structural failures. To assess the extreme load, turbine structural responses are evaluated by conducting field measurement campaigns or performing aeroelastic simulation studies. In general, data obtained in either case are not sufficient to represent various loading responses under all possible weather conditions. An appropriate extrapolation is necessary to characterize the structural loads in a turbines service life. This study devises a Bayesian spline method for this extrapolation purpose and applies the method to three sets of load response data to estimate the corresponding extreme loads at the roots of the turbine blades. In the second study, we propose an additive multivariate kernel method as a new power curve model, which is able to incorporate a variety of environmental factors in addition to merely the wind speed. In the wind industry, a power curve refers to the functional relationship between the power output generated by a wind turbine and the wind speed at the time of power generation. Power curves are used in practice for a number of important tasks including predicting wind power production and assessing a turbines energy production efficiency. Nevertheless, actual wind power data indicate that the power output is affected by more than just wind speed. Several other environmental factors, such as wind direction, air density, humidity, turbulence intensity, and wind shears, have potential impact. Yet, in industry practice, as well as in the literature, current power curve models primarily consider wind speed and, with comparatively less frequency, wind speed and direction. Our model provides, conditional on a given environmental condition, both the point estimation and density estimation of the power output. It is able to capture the nonlinear relationships between environmental factors and wind power output, as well as the high-order inter- action effects among some of the environmental factors. To illustrate the application of the new power curve model, we conduct case studies that demonstrate how the new method can help with quantifying the benefit of vortex generator installation, advising pitch control adjustment, and facilitating the diagnosis of faults.

Lee, Giwhyun

2013-08-01T23:59:59.000Z

406

Theoretical analysis of acceleration measurements in a model of an operating wind turbine.  

Science Conference Proceedings (OSTI)

Wind loading from turbulence and gusts can cause damage in horizontal axis wind turbines. These unsteady loads and the resulting damage initiation and propagation are difficult to predict. Unsteady loads enter at the rotor and are transmitted to the drivetrain. The current generation of wind turbine has drivetrain-mounted vibration and bearing temperature sensors, a nacelle-mounted inertial measurement unit, and a nacelle-mounted anemometer and wind vane. Some advanced wind turbines are also equipped with strain measurements at the root of the rotor. This paper analyzes additional measurements in a rotor blade to investigate the complexity of these unsteady loads. By identifying the spatial distribution, amplitude, and frequency bandwidth of these loads, design improvements could be facilitated to reduce uncertainties in reliability predictions. In addition, dynamic load estimates could be used in the future to control high-bandwidth aerodynamic actuators distributed along the rotor blade to reduce the saturation of slower pitch actuators currently used for wind turbine blades. Local acceleration measurements are made along a rotor blade to infer operational rotor states including deflection and dynamic modal contributions. Previous work has demonstrated that acceleration measurements can be experimentally acquired on an operating wind turbine. Simulations on simplified rotor blades have also been used to demonstrate that mean blade loading can be estimated based on deflection estimates. To successfully apply accelerometers in wind turbine applications for load identification, the spectral and spatial characteristics of each excitation source must be understood so that the total acceleration measurement can be decomposed into contributions from each source. To demonstrate the decomposition of acceleration measurements in conjunction with load estimation methods, a flexible body model has been created with MSC.ADAMS{copyright} The benefit of using a simulation model as opposed to a physical experiment to examine the merits of acceleration-based load identification methods is that models of the structural dynamics and aerodynamics enable one to compare estimates of the deflection and loading with actual values. Realistic wind conditions are applied to the wind turbine and used to estimate the operational displacement and acceleration of the rotor. The per-revolution harmonics dominate the displacement and acceleration response. Turbulent wind produces broadband excitation that includes both the harmonics and modal vibrations, such as the tower modes. Power Spectral Density estimates of the acceleration along the span of the rotor blades indicate that the edge modes may be coupled to the second harmonic.

Adams, Douglas E. (Purdue University, Lafayette, IN); Rumsey, Mark Allen; White, Jonathan Randall

2010-04-01T23:59:59.000Z

407

Luther College Wind Turbine | Open Energy Information  

Open Energy Info (EERE)

Luther College Wind Turbine Luther College Wind Turbine Jump to: navigation, search Name Luther College Wind Turbine Facility Luther College Wind Turbine Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Luther College Wind Energy Project LLC Developer Luther College Energy Purchaser Alliant Energy Location Decorah IA Coordinates 43.30919891°, -91.81617737° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":43.30919891,"lon":-91.81617737,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

408

Power control of a wind farm with active stall wind turbines and AC grid connection  

E-Print Network (OSTI)

turbines with AC connection. The control of other wind farm concepts such as wind farms with DFIG wind

409

NREL: Wind Research - Ventera's VT 10 Turbine Testing and Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Ventera's VT 10 Turbine Testing and Results Ventera's VT 10 Turbine Testing and Results Ventera's VT10 wind turbine. Text Version As part of the National Renewable Energy Laboratory and U.S. Department of Energy (NREL/DOE) Independent Testing project, NREL is testing Ventera's VT10 small wind turbine at the National Wind Technology Center (NWTC). The VT10 is a horizontal-axis downwind, three-bladed turbine rated at 10 kilowatts (kW). Its diameter is 6.7 meters, and it is mounted on a lattice tower with a hub height of 21.7 meters. The VT10 uses a single-phase, grid-connected, permanent-magnet generator that operates at 240 volts AC. Testing Summary The summary of the tests is listed below, along with the final reports. Cumulative Energy Production 3/22/2010: 0; 3/29/2010: 26; 3/31/2010: 74; 4/1/2010: 75; 4/2/2010: 174;

410

Responses of floating wind turbines to wind and wave excitation  

E-Print Network (OSTI)

The use of wind power has recently emerged as a promising alternative to conventional electricity generation. However, space requirements and public pressure to place unsightly wind turbines out of visual range make it ...

Lee, Kwang Hyun

2005-01-01T23:59:59.000Z

411

Certification testing for small wind turbines  

DOE Green Energy (OSTI)

This paper describes the testing procedures for obtaining type certification for a small wind turbine. Southwest Windpower (SWWP) is seeking type certification from Underwriters Laboratory (UL) for the AIR 403 wind turbine. UL is the certification body and the National Renewable Energy Laboratory (NREL) is providing technical assistance including conducting the certification testing. This is the first small turbine to be certified in the US, therefore standards must be interpreted and test procedures developed.

Corbus, D.; Link, H.; Butterfield, S.; Stork, C.; Newcomb, C.

1999-10-20T23:59:59.000Z

412

Towards a Wind Energy Climatology at Advanced Turbine Hub-Heights: Preprint  

DOE Green Energy (OSTI)

Measurements of wind characteristics over a wide range of heights up to and above 100 m are useful to: (1) characterize the local and regional wind climate; (2) validate wind resource estimates derived from numerical models; and (3) evaluate changes in wind characteristics and wind shear over the area swept by the blades. Developing wind climatology at advanced turbine hub heights for the United States benefits wind energy development. Tall tower data from Kansas, Indiana, and Minnesota (which have the greatest number of tall towers with measurement data) will be the focus of this paper. Analyses of data from the tall towers will start the process of developing a comprehensive climatology.

Schwartz, M.; Elliott, D.

2005-05-01T23:59:59.000Z

413

Wind Turbine Towers Establish New Height Standards and Reduce...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Wind Turbine Towers Establish New Height Standards and Reduce Cost of Wind Energy Wind Turbine Towers Establish New Height Standards and Reduce Cost of Wind Energy Case study that...

414

Materials Issues in Innovative Turbine Blade Designs - Oak Ridge National Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Issues in Innovative Turbine Materials Issues in Innovative Turbine Blade Designs-Oak Ridge National Laboratory Background Gas turbine efficiency and service life are strongly affected by the turbine expansion process, where the working fluid's high thermal energy gas is converted into mechanical energy to drive the compressor and the electric generator. The most effective way to increase the efficiency of the expansion process is to raise the temperature of the turbine's working fluid.

415

Meteorological aspects of siting large wind turbines  

DOE Green Energy (OSTI)

This report, which focuses on the meteorological aspects of siting large wind turbines (turbines with a rated output exceeding 100 kW), has four main goals. The first is to outline the elements of a siting strategy that will identify the most favorable wind energy sites in a region and that will provide sufficient wind data to make responsible economic evaluations of the site wind resource possible. The second is to critique and summarize siting techniques that were studied in the Department of Energy (DOE) Wind Energy Program. The third goal is to educate utility technical personnel, engineering consultants, and meteorological consultants (who may have not yet undertaken wind energy consulting) on meteorological phenomena relevant to wind turbine siting in order to enhance dialogues between these groups. The fourth goal is to minimize the chances of failure of early siting programs due to insufficient understanding of wind behavior.

Hiester, T.R.; Pennell, W.T.

1981-01-01T23:59:59.000Z

416

Charlestown Wind Turbine | Open Energy Information  

Open Energy Info (EERE)

Charlestown Wind Turbine Charlestown Wind Turbine Jump to: navigation, search Name Charlestown Wind Turbine Facility Charlestown Wind Turbine Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner MWRA Developer MWRA Energy Purchaser Distributed generation - net metered Location Boston MA Coordinates 42.39094522°, -71.07094288° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":42.39094522,"lon":-71.07094288,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

417

Nature's Classroom Wind Turbine | Open Energy Information  

Open Energy Info (EERE)

Nature's Classroom Wind Turbine Nature's Classroom Wind Turbine Jump to: navigation, search Name Nature's Classroom Wind Turbine Facility Nature's Classroom Wind Turbine Sector Wind energy Facility Type Small Scale Wind Facility Status In Service Owner Nature's Classroom Energy Purchaser Nature's Classroom Location Charlton MA Coordinates 42.113685°, -72.008475° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":42.113685,"lon":-72.008475,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

418

Williams Stone Wind Turbine | Open Energy Information  

Open Energy Info (EERE)

Wind Turbine Wind Turbine Jump to: navigation, search Name Williams Stone Wind Turbine Facility Williams Stone Wind Turbine Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Williams Stone Developer Sustainable Energy Developments Energy Purchaser Williams Stone Location Otis MA Coordinates 42.232526°, -73.070952° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":42.232526,"lon":-73.070952,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

419

Value Capture in the Global Wind Energy Industry  

E-Print Network (OSTI)

of large wind turbine (REpower MM92) Tower Rotor blades GearLiberty turbine, 2008 Component Tower Rotor blades/hub/turbine, 2008 Component Supplier Supplier HQ Tower Gamesa Spain Rotor

Dedrick, Jason; Kraemer, Kenneth L.

2011-01-01T23:59:59.000Z

420

An approach to the development and analysis of wind turbine control algorithms  

DOE Green Energy (OSTI)

The objective of this project is to develop the capability of symbolically generating an analytical model of a wind turbine for studies of control systems. This report focuses on a theoretical formulation of the symbolic equations of motion (EOMs) modeler for horizontal axis wind turbines. In addition to the power train dynamics, a generic 7-axis rotor assembly is used as the base model from which the EOMs of various turbine configurations can be derived. A systematic approach to generate the EOMs is presented using d`Alembert`s principle and Lagrangian dynamics. A Matlab M file was implemented to generate the EOMs of a two-bladed, free yaw wind turbine. The EOMs will be compared in the future to those of a similar wind turbine modeled with the YawDyn code for verification. This project was sponsored by Sandia National Laboratories as part of the Adaptive Structures and Control Task. This is the final report of Sandia Contract AS-0985.

Wu, K.C.

1998-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "wind turbine blades" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

A low order model for vertical axis wind turbines  

E-Print Network (OSTI)

A new computational model for initial sizing and performance prediction of vertical axis wind turbines

Drela, Mark

422

Advanced Wind Turbine Controls Reduce Loads (Fact Sheet)  

DOE Green Energy (OSTI)

NREL's National Wind Technology Center provides the world's only dedicated turbine controls testing platforms.

Not Available

2012-03-01T23:59:59.000Z

423

Loads Analysis of Several Offshore Floating Wind Turbine Concepts  

SciTech Connect

This paper presents a comprehensive dynamic-response analysis of six offshore floating wind turbine concepts.

Robertson, A. N.; Jonkman, J. M.

2011-10-01T23:59:59.000Z

424

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network (OSTI)

of Turbine Rotor . . . . . . . . . . . . . . 3.9 Results ofA. C. (2006). WindPACT turbine rotor design study. ReportA. C. (2006). WindPACT turbine rotor design study. Report

Prowell, I.

2011-01-01T23:59:59.000Z

425

Automatic Detection of Wind Turbine Clutter for Weather Radars  

Science Conference Proceedings (OSTI)

Wind turbines cause contamination of weather radar signals that is often detrimental and difficult to distinguish from cloud returns. Because the turbines are always at the same location, it would seem simple to identify where wind turbine ...

Kenta Hood; Sebastin Torres; Robert Palmer

2010-11-01T23:59:59.000Z

426

Wind Turbine Productivity and Development in Iran  

Science Conference Proceedings (OSTI)

This paper presents an overview of the status of wind energy productivity and development issues in Iran. It also presents a summary of the present global work on offshore energy, including the most recent works as well as potential offshore wind energy ... Keywords: Iran, development, offshore, turbine, wind

Ali Mostafaeipour; Saeid Abesi

2010-03-01T23:59:59.000Z

427

Structural health and prognostics management for offshore wind turbines : an initial roadmap.  

Science Conference Proceedings (OSTI)

Operations and maintenance costs for offshore wind plants are expected to be significantly higher than the current costs for onshore plants. One way in which these costs may be able to be reduced is through the use of a structural health and prognostic management system as part of a condition based maintenance paradigm with smart load management. To facilitate the creation of such a system a multiscale modeling approach has been developed to identify how the underlying physics of the system are affected by the presence of damage and how these changes manifest themselves in the operational response of a full turbine. The developed methodology was used to investigate the effects of a candidate blade damage feature, a trailing edge disbond, on a 5-MW offshore wind turbine and the measurements that demonstrated the highest sensitivity to the damage were the local pitching moments around the disbond. The multiscale method demonstrated that these changes were caused by a local decrease in the blade's torsional stiffness due to the disbond, which also resulted in changes in the blade's local strain field. Full turbine simulations were also used to demonstrate that derating the turbine power by as little as 5% could extend the fatigue life of a blade by as much as a factor of 3. The integration of the health monitoring information, conceptual repair cost versus damage size information, and this load management methodology provides an initial roadmap for reducing operations and maintenance costs for offshore wind farms while increasing turbine availability and overall profit.

Griffith, Daniel Todd; Resor, Brian Ray; White, Jonathan Randall; Paquette, Joshua A.; Yoder, Nathanael C. [ATA Engineering, San Diego, CA

2012-12-01T23:59:59.000Z

428

Investigation of aerodynamic braking devices for wind turbine applications  

DOE Green Energy (OSTI)

This report documents the selection and preliminary design of a new aerodynamic braking system for use on the stall-regulated AWT-26/27 wind turbines. The goal was to identify and design a configuration that offered improvements over the existing tip brake used by Advanced Wind Turbines, Inc. (AWT). Although the design objectives and approach of this report are specific to aerodynamic braking of AWT-26/27 turbines, many of the issues addressed in this work are applicable to a wider class of turbines. The performance trends and design choices presented in this report should be of general use to wind turbine designers who are considering alternative aerodynamic braking methods. A literature search was combined with preliminary work on device sizing, loads and mechanical design. Candidate configurations were assessed on their potential for benefits in the areas of cost, weight, aerodynamic noise, reliability and performance under icing conditions. As a result, two configurations were identified for further study: the {open_quotes}spoiler-flap{close_quotes} and the {open_quotes}flip-tip.{close_quotes} Wind tunnel experiments were conducted at Wichita State University to evaluate the performance of the candidate aerodynamic brakes on an airfoil section representative of the AWT-26/27 blades. The wind tunnel data were used to predict the braking effectiveness and deployment characteristics of the candidate devices for a wide range of design parameters. The evaluation was iterative, with mechanical design and structural analysis being conducted in parallel with the braking performance studies. The preliminary estimate of the spoiler-flap system cost was $150 less than the production AWT-26/27 tip vanes. This represents a reduction of approximately 5 % in the cost of the aerodynamic braking system. In view of the preliminary nature of the design, it would be prudent to plan for contingencies in both cost and weight.

Griffin, D.A. [R. Lynette & Associates, Seattle, WA (United States)

1997-04-01T23:59:59.000Z

429

Acoustic ranging technique with application to assessment of low-frequency acoustic noise of wind turbines  

DOE Green Energy (OSTI)

Impulsive low-frequency noise from wind turbines can cause annoyance particularly when a residential structure is involved. Such noise is typically generated in some spatially restricted region of a turbine rotor swept area. Low-frequency impulsive noise of the MOD-1 turbine was generated when the rotor blades passed downwind of the tower legs encountering the complex unsteady flows there. An acoustic ranging technique that aids assessment of the degree of concentration of acoustic generation within the turbine swept area and which determines the time-average spatial source region of such concentration is described. Practical applications and limitations of the process are discussed.

Hemphill, R.

1983-05-01T23:59:59.000Z

430

Dynamic analysis of a 5 megawatt offshore floating wind turbine  

E-Print Network (OSTI)

Enabling New Markets for Offshore Wind Energy." Proc. ofMary, and Laura Parsons. Offshore Wind Energy. Washingto,Challenges for Floating Offshore Wind Turbines. Tech. no.

Harriger, Evan Michael

2011-01-01T23:59:59.000Z

431

Solving Wind Turbine Tribological Issues with Materials Science  

Science Conference Proceedings (OSTI)

Abstract Scope, Wind energy is becoming more important to society as we are ... Large wind turbines convert the mechanical energy harnessed from the wind...

432

Wind turbine having a direct-drive drivetrain - Energy Innovation ...  

A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor ...

433

Methods and apparatus for reducing peak wind turbine loads ...  

A method for reducing peak loads of wind turbines in a changing wind environment includes measuring or estimating an instantaneous wind speed and direction at the ...

434

Dynamic analysis of a 5 megawatt offshore floating wind turbine  

E-Print Network (OSTI)

Enabling New Markets for Offshore Wind Energy." Proc. ofand Laura Parsons. Offshore Wind Energy. Washingto, DC:Challenges for Floating Offshore Wind Turbines. Tech. no.

Harriger, Evan Michael

2011-01-01T23:59:59.000Z

435

Theoretical and experimental power from large horizontal-axis wind turbines  

SciTech Connect

A method for calculating the output power from large horizontal-axis wind turbines is presented. Modifications to the airfoil characteristics and the momentum portion of classical blade element-momentum theory are given that improve correlation with measured data. Improvement is particularly evident at low tip speed ratios where aerodynamic stall can occur as the blade experiences high angles of attack. Output power calculated using the modified theory is compared with measured data for several large wind turbines. These wind turbines range in size from the DOE/NASA 100 kW Mod-O (38 m rotor diameter) to the 2000 kW Mod-1 (61 m rotor diameter). The calculated results are in good agreement with measured data from these machines.

Viterna, L A; Janetzke, D C

1982-09-01T23:59:59.000Z

436

Advanced Control Design and Field Testing for Wind Turbines at the National Renewable Energy Laboratory: Preprint  

DOE Green Energy (OSTI)

Utility-scale wind turbines require active control systems to operate at variable rotational speeds. As turbines become larger and more flexible, advanced control algorithms become necessary to meet multiple objectives such as speed regulation, blade load mitigation, and mode stabilization. At the same time, they must maximize energy capture. The National Renewable Energy Laboratory has developed control design and testing capabilities to meet these growing challenges.

Hand, M. M.; Johnson, K. E.; Fingersh, L. J.; Wright, A. D.

2004-05-01T23:59:59.000Z

437

Improving the manufacturing yield of investment cast turbine blades through robust design  

E-Print Network (OSTI)

The manufacturing of turbine blades is often outsourced to investment casting foundries by aerospace companies that design and build jet engines. Aerospace companies have found that casting defects are an important cost ...

Margetts, David (David Lawrence)

2008-01-01T23:59:59.000Z

438

Nonlinear Control of a Wind Turbine Sven Creutz Thomsen  

E-Print Network (OSTI)

. This quantity is denoted the point wind. However, the turbine is not subject to a single wind speed, but ratherNonlinear Control of a Wind Turbine Sven Creutz Thomsen Kongens Lyngby 2006 #12;Technical describes analysis of various nonlinear control methods for controlling a wind turbine. High speed wind

439

Dual-speed wind turbine generation  

SciTech Connect

Induction generator has been used since the early development of utility-scale wind turbine generation. An induction generator is the generator of choice because of its ruggedness and low cost. With an induction generator, the operating speed of the wind turbine is limited to a narrow range (almost constant speed). Dual- speed operation can be accomplished by using an induction generator with two different sets of winding configurations or by using a dual output drive train to drive two induction generators with two different rated speeds. With single-speed operation, the wind turbine operates at different power coefficients (Cp) as the wind speed varies. Operation at maximum Cp can occur only at a single wind speed. However, if the wind speed.varies across a wider range, the operating Cp will vary significantly. Dual-speed operation has the advantage of enabling the wind turbine to operate at near maximum Cp over a wider range of wind speeds. Thus, annual energy production can be increased. The dual-speed mode may generate less energy than a variable-speed mode; nevertheless, it offers an alternative which captures more energy than single-speed operation. In this paper, dual-speed operation of a wind turbine is investigated. Annual energy production is compared between single-speed and dual-speed operation. One type of control algorithm for dual-speed operation is proposed. Some results from a dynamic simulation will be presented to show how the control algorithm works as the wind turbine is exposed to varying wind speeds.

Muljadi, E.; Butterfield, C.P. [National Renewable Energy Lab., Golden, CO (United States); Handman, D. [Flowind Corp., San Rafael, CA (United States)

1996-10-01T23:59:59.000Z

440

A Study on Vibration Isolation in a Wind Turbine Subjected to Wind and Seismic Loading.  

E-Print Network (OSTI)

??The primary loading on wind turbines is in the lateral direction and is of a stochastic nature, due to wind and seismic forces. As turbines (more)

Van der Woude, Chad

2011-01-01T23:59:59.000Z