Sample records for maximum blade height

  1. Parameterization of Maximum Wave Heights Forced by Hurricanes: Application to Corpus Christi, Texas

    E-Print Network [OSTI]

    Taylor, Sym 1978-

    2012-12-07T23:59:59.000Z

    sensitivity based on the investigation of several hurricane parameters. Also presented is the development of parameterized maximum significant wave height models. These are determined by incorporating three forms of an equivalent fetch into (1) dimensionless...

  2. Ceramic blade attachment system

    DOE Patents [OSTI]

    Boyd, G.L.

    1995-04-11T23:59:59.000Z

    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.

  3. Ceramic blade attachment system

    DOE Patents [OSTI]

    Boyd, Gary L. (Alpine, CA)

    1995-01-01T23:59:59.000Z

    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.

  4. Sparkr Blade Test Centre Fatigue tests of wind turbine blades

    E-Print Network [OSTI]

    Sparkær Blade Test Centre Fatigue tests of wind turbine blades Flapwise fatigue tests of 3 blades wind load. By turning and oscillating the blade in the horzontal direction, an R-ratio of ­1 running at the Sparkær Centre Blade Test Facilities. Fatigue blade tests are performed in order

  5. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, J.E.

    1995-07-11T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figs.

  6. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, James E. (Maitland, FL)

    1995-01-01T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.

  7. An experimental investigation of turbine blade heat transfer and turbine blade trailing edge cooling

    E-Print Network [OSTI]

    Choi, Jungho

    2005-02-17T23:59:59.000Z

    and turbulence intensity, respectively. The cascade inlet Reynolds number based on blade chord length was varied from 15,700 to 105,000, and the Strouhal number was varied from 0 to 2.96 by changing the rotating wake passing frequency (rod speed) and cascade... on the trailing edge (m) d rotating rod diameter e rib height h local heat transfer coefficient ( K2 ) k thermal conductivity of air at C (0.02598 mKW /) M Blowing ratio ( m c V V ) N RPM of rotating rod Nu local Nusselt number based on blade...

  8. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, J.E.

    1995-01-10T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figures.

  9. Turbine blade platform seal

    DOE Patents [OSTI]

    Zagar, Thomas W. (Winter Springs, FL); Schiavo, Anthony L. (Oviedo, FL)

    2001-01-01T23:59:59.000Z

    A rotating blade group 90 for a turbo-machine having an improved device for sealing the gap 110 between the edges 112,114 of adjacent blade platforms 96,104. The gap 110 between adjacent blades 92,100 is sealed by a seal pin 20 its central portion 110 and by a seal plate 58,60 at each of the front 54 and rear 56 portions. The seal plates 58,60 are inserted into corresponding grooves 62,64 formed in the adjacent edges 112,114 of adjoining blades 92,100 and held in place by end plates 40,42. The end of the seal plates 58,60 may be chamfered 78,80 to improve the seal against the end plate 40,42. The seal pin 20 provides the required damping between the blades 92,100 and the seal plates 58,60 provide improved sealing effectiveness.

  10. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, James E. (Maitland, FL)

    1995-01-01T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.

  11. Sparkr Blade Test Centre Modal Analysis of Wind Turbine Blades

    E-Print Network [OSTI]

    Sparkær Blade Test Centre Modal Analysis of Wind Turbine Blades Modal analysis is the process the modes constitute a complete dynamic description of the wind turbine blade. The modes of vibration represent the inherent dynamic properties of the wind turbine blade. The range of applications for modal

  12. Sparkr Blade Test Centre Static tests of wind turbine blades

    E-Print Network [OSTI]

    Sparkær Blade Test Centre Static tests of wind turbine blades Static blade tests are performed down- and up-wind direction, and in the rotor thrust direction and opposite to that, respectively-4000 Roskilde Denmark www.risoe.dk Wind Energy Department Sparkær Blade test Centre vea@risoe.dk Tel

  13. Ceramic blade attachment system

    DOE Patents [OSTI]

    Boyd, G.L.

    1994-12-13T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a pair of recessed portions thereon. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings have a pair of grooves therein in which are positioned a pair of pins having a generally rectangular cross-section and a reaction surface thereon. A pair of cylindrical rollers interposed respective ones of the pair of reaction surfaces and the pair of recessed portions. The attachment system or turbine assembly provides an economical, reliable and effective attachment of a component having a preestablished rate of thermal expansion to a component having a greater preestablished rate of thermal expansion. 3 figures.

  14. Ceramic blade attachment system

    DOE Patents [OSTI]

    Boyd, Gary L. (Alpine, CA)

    1994-01-01T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a pair of recessed portions thereon. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings have a pair of grooves therein in which are positioned a pair of pins having a generally rectangular cross-section and a reaction surface thereon. A pair of cylindrical rollers interposed respective ones of the pair of reaction surfaces and the pair of recessed portions. The attachment system or turbine assembly provides an economical, reliable and effective attachment of a component having a preestablished rate of thermal expansion to a component having a greater preestablished rate of thermal expansion.

  15. Blade Testing Trends (Presentation)

    SciTech Connect (OSTI)

    Desmond, M.

    2014-08-01T23:59:59.000Z

    As an invited guest speaker, Michael Desmond presented on NREL's NWTC structural testing methods and capabilities at the 2014 Sandia Blade Workshop held on August 26-28, 2014 in Albuquerque, NM. Although dynamometer and field testing capabilities were mentioned, the presentation focused primarily on wind turbine blade testing, including descriptions and capabilities for accredited certification testing, historical methodology and technology deployment, and current research and development activities.

  16. Ceramic blade attachment system

    DOE Patents [OSTI]

    Frey, G.A.; Jimenez, O.D.

    1996-12-03T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed between them. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. A pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade. 4 figs.

  17. Ceramic blade attachment system

    DOE Patents [OSTI]

    Frey, deceased, Gary A. (late of Poway, CA); Jimenez, Oscar D. (Escondia, CA)

    1996-01-01T23:59:59.000Z

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed therebetween. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. And, a pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade.

  18. Fluid blade disablement tool

    DOE Patents [OSTI]

    Jakaboski, Juan-Carlos (Albuquerque, NM); Hughs, Chance G. (Albuquerque, NM); Todd, Steven N. (Rio Rancho, NM)

    2012-01-10T23:59:59.000Z

    A fluid blade disablement (FBD) tool that forms both a focused fluid projectile that resembles a blade, which can provide precision penetration of a barrier wall, and a broad fluid projectile that functions substantially like a hammer, which can produce general disruption of structures behind the barrier wall. Embodiments of the FBD tool comprise a container capable of holding fluid, an explosive assembly which is positioned within the container and which comprises an explosive holder and explosive, and a means for detonating. The container has a concavity on the side adjacent to the exposed surface of the explosive. The position of the concavity relative to the explosive and its construction of materials with thicknesses that facilitate inversion and/or rupture of the concavity wall enable the formation of a sharp and coherent blade of fluid advancing ahead of the detonation gases.

  19. Cooled snubber structure for turbine blades

    DOE Patents [OSTI]

    Mayer, Clinton A; Campbell, Christian X; Whalley, Andrew; Marra, John J

    2014-04-01T23:59:59.000Z

    A turbine blade assembly in a turbine engine. The turbine blade assembly includes a turbine blade and a first snubber structure. The turbine blade includes an internal cooling passage containing cooling air. The first snubber structure extends outwardly from a sidewall of the turbine blade and includes a hollow interior portion that receives cooling air from the internal cooling passage of the turbine blade.

  20. heap height (ft) box height (ft)

    E-Print Network [OSTI]

    heap height (ft) box height (ft) width (ft) length (ft) Best Environmental Management Practices it analyzed to determine the nutrient content of each sample; and 4. Calculate the amount of manure rates and patterns, depending on speed and/or power take-off (PTO) speed, gearbox settings, gate

  1. Snubber assembly for turbine blades

    DOE Patents [OSTI]

    Marra, John J

    2013-09-03T23:59:59.000Z

    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.

  2. Sandia National Laboratories: flexible blades

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    blades Sandia Vertical-Axis Wind-Turbine Research Presented at Science of Making Torque from Wind Conference On July 8, 2014, in Computational Modeling & Simulation, Energy, News,...

  3. Ceramic blade with tip seal

    DOE Patents [OSTI]

    Glezer, B.; Bhardwaj, N.K.; Jones, R.B.

    1997-08-05T23:59:59.000Z

    The present gas turbine engine includes a disc assembly defining a disc having a plurality of blades attached thereto. The disc has a preestablished rate of thermal expansion and the plurality of blades have a preestablished rate of thermal expansion being less than the preestablished rate of thermal expansion of the disc. A shroud assembly is attached to the gas turbine engine and is spaced from the plurality of blades a preestablished distance forming an interface there between. Positioned in the interface is a seal having a preestablished rate of thermal expansion being generally equal to the rate of thermal expansion of the plurality of blades. 4 figs.

  4. Driver eye height measurement

    E-Print Network [OSTI]

    Abrahamson, Anthony Daniel

    1978-01-01T23:59:59.000Z

    DRIVER EYF HEIGHT MFASHRFMENT A Thesis by ANTHONY DANIEL ABRAHAMSON Submitted to the Graduate College of Texas A&M Hniversity in partial fulfillment oi the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subje"t: Civil... Engineering DRIVER EYE HEIGHT MEASUREMENT A Thesis by ANTHONY DANIEL ABRAHAMSON Approved as to style and content by: I (C irman of Committee) (Member) (Memb er ) Head of Department) December 1978 ABSTRACT Driver. Eye Height Neasurement. (December...

  5. Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition

    SciTech Connect (OSTI)

    Li, Ye; Karri, Naveen K.; Wang, Qi

    2014-04-30T23:59:59.000Z

    Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its advantages over the wind and other renewal energy sources. The technology used to harvest energy from tidal current is called a tidal current turbine. Though some of the principles of wind turbine design are applicable to tidal current turbines, the design of latter ones need additional considerations like cavitation damage, corrosion etc. for the long-term reliability of such turbines. Depending up on the orientation of axis, tidal current turbines can be classified as vertical axis turbines or horizontal axis turbines. Existing studies on the vertical axis tidal current turbine focus more on the hydrodynamic aspects of the turbine rather than the structural aspects. This paper summarizes our recent efforts to study the integrated hydrodynamic and structural aspects of the vertical axis tidal current turbines. After reviewing existing methods in modeling tidal current turbines, we developed a hybrid approach that combines discrete vortex method -finite element method that can simulate the integrated hydrodynamic and structural response of a vertical axis turbine. This hybrid method was initially employed to analyze a typical three-blade vertical axis turbine. The power coefficient was used to evaluate the hydrodynamic performance, and critical deflection was considered to evaluate the structural reliability. A sensitivity analysis was also conducted with various turbine height-to-radius ratios. The results indicate that both the power output and failure probability increase with the turbine height, suggesting a necessity for optimal design. An attempt to optimize a 3-blade vertical axis turbine design with hybrid method yielded a ratio of turbine height to radius (H/R) about 3.0 for reliable maximum power output.

  6. Advanced Manufacturing Initiative Improves Turbine Blade Productivity...

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

    Advanced Manufacturing Initiative Improves Turbine Blade Productivity Advanced Manufacturing Initiative Improves Turbine Blade Productivity May 20, 2011 - 2:56pm Addthis This is an...

  7. Sandia National Laboratories: utility-scale blade

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    blade Fabrication of AMI Demonstration Blade Begun On September 10, 2013, in Energy, News, News & Events, Partnership, Renewable Energy, Wind Energy The Advanced Manufacturing...

  8. Sandia National Laboratories: Radar Friendly Blades

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    MitigationRadar Friendly Blades Radar Friendly Blades Some wind farms have the potential to cause interference with the normal operation of radar systems used for security, weather...

  9. SERI advanced wind turbine blades

    SciTech Connect (OSTI)

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

    1992-02-01T23:59:59.000Z

    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.

  10. SERI advanced wind turbine blades

    SciTech Connect (OSTI)

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

    1992-02-01T23:59:59.000Z

    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.

  11. Property:Maximum Wave Height(m) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid JumpEligSysSize JumpTechDsc Jump to:

  12. Wooden wind turbine blade manufacturing process

    DOE Patents [OSTI]

    Coleman, Clint (Warren, VT)

    1986-01-01T23:59:59.000Z

    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.

  13. Turbine blade cooling

    DOE Patents [OSTI]

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

    2000-01-01T23:59:59.000Z

    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.

  14. Turbine blade cooling

    DOE Patents [OSTI]

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

    1999-07-20T23:59:59.000Z

    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.

  15. Turbine blade cooling

    DOE Patents [OSTI]

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

    1999-07-20T23:59:59.000Z

    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.

  16. Multiple piece turbine blade

    DOE Patents [OSTI]

    Kimmel, Keith D (Jupiter, FL)

    2012-05-29T23:59:59.000Z

    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.

  17. Ceramic blade with tip seal

    DOE Patents [OSTI]

    Glezer, Boris (Del Mar, CA); Bhardwaj, Narender K. (San Diego, CA); Jones, Russell B. (San Diego, CA)

    1997-01-01T23:59:59.000Z

    The present gas turbine engine (10) includes a disc assembly (64) defining a disc (66) having a plurality of blades (70) attached thereto. The disc (66) has a preestablished rate of thermal expansion and the plurality of blades have a preestablished rate of thermal expansion being less than the preestablished rate of thermal expansion of the disc (66). A shroud assembly (100) is attached to the gas turbine engine (10) and is spaced from the plurality of blades (70) a preestablished distance forming an interface (108) therebetween. Positioned in the interface is a seal (110) having a preestablished rate of thermal expansion being generally equal to the rate of thermal expansion of the plurality of blades (70).

  18. 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...

  19. Paramedian forehead flap thinning using a flexible razor blade

    E-Print Network [OSTI]

    Justiniano, Hilda; Edwards, Julia; Eisen, Daniel B

    2009-01-01T23:59:59.000Z

    et al. , The use of a flexible razor blade in skin graftflap thinning using a flexible razor blade Hilda Justinianoforehead flap using a flexible razor blade, the Dermablade.

  20. Probabilistic analysis of turbine blade durability

    E-Print Network [OSTI]

    Kountras, Apostolos, 1970-

    2004-01-01T23:59:59.000Z

    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 ...

  1. Blade for a gas turbine

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-10-26T23:59:59.000Z

    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.

  2. Articulated limiter blade for a tokamak fusion reactor

    DOE Patents [OSTI]

    Doll, D.W.

    1982-10-21T23:59:59.000Z

    A limiter blade for a large tokomak fusion reactor includes three articulated blade sections for enabling the limiter blade to be adjusted for plasmas of different sizes. Each blade section is formed of a rigid backing plate carrying graphite tiles coated with titanium carbide, and the limiter blade forms a generally elliptic contour in both the poloidal and toroidal directions to uniformly distribute the heat flow to the blade. The limiter blade includes a central blade section movable along the major radius of the vacuum vessel, and upper and lower pivotal blade sections which may be pivoted by linear actuators having rollers held to the back surface of the pivotal blade sections.

  3. Articulated limiter blade for a tokamak fusion reactor

    DOE Patents [OSTI]

    Doll, David W. (San Diego, CA)

    1985-01-01T23:59:59.000Z

    A limiter blade for a large tokomak fusion reactor includes three articulated blade sections for enabling the limiter blade to be adjusted for plasmas of different sizes. Each blade section is formed of a rigid backing plate carrying graphite tiles coated with titanium carbide, and the limiter blade forms a generally elliptic contour in both the poloidal and toroidal directions to uniformly distribute the heat flow to the blade. The limiter blade includes a central blade section movable along the major radius of the vacuum vessel, and upper and lower pivotal blade sections which may be pivoted by linear actuators having rollers held to the back surface of the pivotal blade sections.

  4. Turbine blade tip gap reduction system

    DOE Patents [OSTI]

    Diakunchak, Ihor S.

    2012-09-11T23:59:59.000Z

    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.

  5. Rotor blades for turbine engines

    DOE Patents [OSTI]

    Piersall, Matthew R; Potter, Brian D

    2013-02-12T23:59:59.000Z

    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.

  6. Blade dynamics and flux measurements for model seagrass blades in waves and currents

    E-Print Network [OSTI]

    Connor, Erin Grace

    2014-01-01T23:59:59.000Z

    Complex interactions between flow conditions, blade posture, and mass transport processes, represent a challenge to fully understanding the influence of hydrodynamic conditions on the flux of nutrients to the blade surface ...

  7. Load attenuating passively adaptive wind turbine blade

    DOE Patents [OSTI]

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

    2003-01-01T23:59:59.000Z

    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.

  8. Load attenuating passively adaptive wind turbine blade

    DOE Patents [OSTI]

    Veers, Paul S.; Lobitz, Donald W.

    2003-01-07T23:59:59.000Z

    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.

  9. Cooling arrangement for a tapered turbine blade

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-07-27T23:59:59.000Z

    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.

  10. 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

  11. Sandia National Laboratories: Blade Reliability Collaborative

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Generator Modeling Radar Friendly Blades Special Programs Techno-Economic Modeling, Analysis, and Support Analysis, Modeling, Cost of Energy, and Policy Impact: Wind Vision 2014...

  12. Sandia National Laboratories: Wind Turbine Blade Design

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Wind Turbine Blade Design National Rotor Testbed Functional Scaling Presented at American Institute of Aeronautics and Astronautics 2014 Scitech On April 15, 2014, in Energy,...

  13. Evaluation of Turbine Blades Using Computed Tomography

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

    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.

  14. Sandia National Laboratories: wind turbine blade materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    materials Wind-Turbine Blade Materials and Reliability Progress On May 21, 2014, in Energy, Materials Science, News, News & Events, Partnership, Renewable Energy, Research &...

  15. The motion of kelp blades and the surface renewal model

    E-Print Network [OSTI]

    Huang, Ivy

    2011-01-01T23:59:59.000Z

    We consider how the flapping of kelp blades may enhance the flux of nutrients to a blade, by stripping away the diffusive sub-layer and renewing the fluid at the blade surface. The surface renewal model explains the degree ...

  16. Adaptor assembly for coupling turbine blades to rotor disks

    DOE Patents [OSTI]

    Garcia-Crespo, Andres Jose; Delvaux, John McConnell

    2014-09-23T23:59:59.000Z

    An adaptor assembly for coupling a blade root of a turbine blade to a root slot of a rotor disk is described. The adaptor assembly includes a turbine blade having a blade root and an adaptor body having an adaptor root. The adaptor body defines a slot having an open end configured to receive the blade root of the turbine blade such that the adaptor root of the adaptor body and the blade root of the turbine blade are adjacent to one another when the blade root of the turbine blade is positioned within the slot. Both the adaptor root of the adaptor body and the blade root of the turbine blade are configured to be received within the root slot of the rotor disk.

  17. Multiple piece turbine rotor blade

    DOE Patents [OSTI]

    Jones, Russell B; Fedock, John A

    2013-05-21T23:59:59.000Z

    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.

  18. Sandia National Laboratories: larger and heavier turbine blades...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    larger and heavier turbine blades experience increased edgewise fatigue loading New Material Tests Show Biaxial Laminate Creep Is Important for Large Wind-Turbine Blades On April...

  19. Sandia National Laboratories: test wind turbine blade structures...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    wind turbine blade structures at an intermediate scale Wind-Turbine Blade Materials and Reliability Progress On May 21, 2014, in Energy, Materials Science, News, News & Events,...

  20. Massachusetts Large Blade Test Facility Final Report

    SciTech Connect (OSTI)

    Rahul Yarala; Rob Priore

    2011-09-02T23:59:59.000Z

    Project Objective: The Massachusetts Clean Energy Center (CEC) will design, construct, and ultimately have responsibility for the operation of the Large Wind Turbine Blade Test Facility, which is an advanced blade testing facility capable of testing wind turbine blades up to at least 90 meters in length on three test stands. Background: Wind turbine blade testing is required to meet international design standards, and is a critical factor in maintaining high levels of reliability and mitigating the technical and financial risk of deploying massproduced wind turbine models. Testing is also needed to identify specific blade design issues that may contribute to reduced wind turbine reliability and performance. Testing is also required to optimize aerodynamics, structural performance, encourage new technologies and materials development making wind even more competitive. The objective of this project is to accelerate the design and construction of a large wind blade testing facility capable of testing blades with minimum queue times at a reasonable cost. This testing facility will encourage and provide the opportunity for the U.S wind industry to conduct more rigorous testing of blades to improve wind turbine reliability.

  1. Advanced Blade Manufacturing Project - Final Report

    SciTech Connect (OSTI)

    POORE, ROBERT Z.

    1999-08-01T23:59:59.000Z

    The original scope of the project was to research improvements to the processes and materials used in the manufacture of wood-epoxy blades, conduct tests to qualify any new material or processes for use in blade design and subsequently build and test six blades using the improved processes and materials. In particular, ABM was interested in reducing blade cost and improving quality. In addition, ABM needed to find a replacement material for the mature Douglas fir used in the manufacturing process. The use of mature Douglas fir is commercially unacceptable because of its limited supply and environmental concerns associated with the use of mature timber. Unfortunately, the bankruptcy of FloWind in June 1997 and a dramatic reduction in AWT sales made it impossible for ABM to complete the full scope of work. However, sufficient research and testing were completed to identify several promising changes in the blade manufacturing process and develop a preliminary design incorporating these changes.

  2. Turbine blade damping device with controlled loading

    DOE Patents [OSTI]

    Marra, John J

    2013-09-24T23:59:59.000Z

    A damping structure for a turbomachine rotor. The damping structure including an elongated snubber element including a first snubber end rigidly attached to a first blade and extending toward an adjacent second blade, and an opposite second snubber end positioned adjacent to a cooperating surface associated with the second blade. The snubber element has a centerline extending radially inwardly in a direction from the first blade toward the second blade along at least a portion of the snubber element between the first and second snubber ends. Rotational movement of the rotor effects relative movement between the second snubber end and the cooperating surface to position the second snubber end in frictional engagement with the cooperating surface with a predetermined damping force determined by a centrifugal force on the snubber element.

  3. Method of making a wooden wind turbine blade

    DOE Patents [OSTI]

    Coleman, C.

    1984-08-14T23:59:59.000Z

    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.

  4. Method of making a wooden wind turbine blade

    DOE Patents [OSTI]

    Coleman, Clint (Warren, VT)

    1984-01-01T23:59:59.000Z

    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.

  5. A Simplified Morphing Blade for Horizontal Axis Wind Turbines

    E-Print Network [OSTI]

    Boyer, Edmond

    A Simplified Morphing Blade for Horizontal Axis Wind Turbines Weijun WANG , St´ephane CARO, Fouad salinas@hotmail.com The aim of designing wind turbine blades is to improve the power capture ability by adjusting the twist of the blade's root and tip. To evaluate the performance of wind turbine blades

  6. Variable diameter wind turbine rotor blades

    DOE Patents [OSTI]

    Jamieson, Peter McKeich; Hornzee-Jones, Chris; Moroz, Emilian M.; Blakemore, Ralph W.

    2005-12-06T23:59:59.000Z

    A system and method for changing wind turbine rotor diameters to meet changing wind speeds and control system loads is disclosed. The rotor blades on the wind turbine are able to adjust length by extensions nested within or containing the base blade. The blades can have more than one extension in a variety of configurations. A cable winching system, a hydraulic system, a pneumatic system, inflatable or elastic extensions, and a spring-loaded jack knife deployment are some of the methods of adjustment. The extension is also protected from lightning by a grounding system.

  7. Pin and roller attachment system for ceramic blades

    DOE Patents [OSTI]

    Shaffer, James E. (Maitland, FL)

    1995-01-01T23:59:59.000Z

    In a turbine, a plurality of blades are attached to a turbine wheel by way of a plurality of joints which form a rolling contact between the blades and the turbine wheel. Each joint includes a pin and a pair of rollers to provide rolling contact between the pin and an adjacent pair of blades. Because of this rolling contact, high stress scuffing between the blades and the turbine wheel reduced, thereby inhibiting catastrophic failure of the blade joints.

  8. Pin and roller attachment system for ceramic blades

    DOE Patents [OSTI]

    Shaffer, J.E.

    1995-07-25T23:59:59.000Z

    In a turbine, a plurality of blades are attached to a turbine wheel by way of a plurality of joints which form a rolling contact between the blades and the turbine wheel. Each joint includes a pin and a pair of rollers to provide rolling contact between the pin and an adjacent pair of blades. Because of this rolling contact, high stress scuffing between the blades and the turbine wheel reduced, thereby inhibiting catastrophic failure of the blade joints. 3 figs.

  9. PREDICTION OF CUTTINGS BED HEIGHT WITH COMPUTATIONAL FLUID DYNAMICS IN DRILLING HORIZONTAL AND HIGHLY DEVIATED WELLS

    E-Print Network [OSTI]

    Ullmer, Brygg

    PREDICTION OF CUTTINGS BED HEIGHT WITH COMPUTATIONAL FLUID DYNAMICS IN DRILLING HORIZONTAL parameters such as wellbore geometry, pump rate, drilling fluid rheology and density, and maximum drilling Computational Fluid Dynamics methods. Movement, concentration and accumulation of drilled cuttings in non

  10. 2014 Sandia Wind Turbine Blade Workshop

    Broader source: Energy.gov [DOE]

    The U.S. Energy Department's Sandia National Laboratories will host its 2014 Sandia Wind Turbine Blade Workshop at the Marriott Pyramid North in Albuquerque, New Mexico. The workshop provides a unique, blade focused collaborative forum that will bring together wind energy leaders from industry, academia, and government. Stay tuned for updates. Information regarding past Wind Workshops can be found at: http://windworkshops.sandia.gov/.

  11. Performance of twist-coupled blades on variable speed rotors

    SciTech Connect (OSTI)

    Lobitz, D.W.; Veers, P.S.; Laino, D.J.

    1999-12-07T23:59:59.000Z

    The load mitigation and energy capture characteristics of twist-coupled HAWT blades that are mounted on a variable speed rotor are investigated in this paper. These blades are designed to twist toward feather as they bend with pretwist set to achieve a desirable twist distribution at rated power. For this investigation, the ADAMS-WT software has been modified to include blade models with bending-twist coupling. Using twist-coupled and uncoupled models, the ADAMS software is exercised for steady wind environments to generate C{sub p} curves at a number of operating speeds to compare the efficiencies of the two models. The ADAMS software is also used to generate the response of a twist-coupled variable speed rotor to a spectrum of stochastic wind time series. This spectrum contains time series with two mean wind speeds at two turbulence levels. Power control is achieved by imposing a reactive torque on the low speed shaft proportional to the RPM squared with the coefficient specified so that the rotor operates at peak efficiency in the linear aerodynamic range, and by limiting the maximum RPM to take advantage of the stall controlled nature of the rotor. Fatigue calculations are done for the generated load histories using a range of material exponents that represent materials from welded steel to aluminum to composites, and results are compared with the damage computed for the rotor without twist-coupling. Results indicate that significant reductions in damage are achieved across the spectrum of applied wind loading without any degradation in power production.

  12. High efficiency turbine blade coatings.

    SciTech Connect (OSTI)

    Youchison, Dennis L.; Gallis, Michail A.

    2014-06-01T23:59:59.000Z

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600 oC and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the production of layered periodic microstructures in the coating, the Direct Simulation Monte Carlo (DSMC) modeling of particle transport in the PVD plume, functional graded layer development, the deposition of all layers to form a complete coating, and materials characterization including thermal testing. Ion beam-assisted deposition, beam sharing through advanced digital rastering, substrate pivoting, hearth calorimetry, infrared imaging, fiber optic-enabled optical emission spectroscopy and careful thermal management were used to achieve all the milestones outlined in the FY02 LDRD proposal.

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

    SciTech Connect (OSTI)

    Bir, G. S.

    2010-09-01T23:59:59.000Z

    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.

  14. The SNL100-01 blade : carbon design studies for the Sandia 100-meter blade.

    SciTech Connect (OSTI)

    Griffith, Daniel Todd

    2013-02-01T23:59:59.000Z

    A series of design studies to investigate the effect of carbon on blade weight and performance for large blades was performed using the Sandia 100-meter All-glass Baseline Blade design as a starting point. This document provides a description of the final carbon blade design, which is termed as SNL100-01. This report includes a summary of the design modifications applied to the baseline all-glass 100-meter design and a description of the NuMAD model files that are made publicly available. This document is intended primarily to be a companion document to the distribution of the NuMAD blade model files for SNL100-01.

  15. 3X-100 blade field test.

    SciTech Connect (OSTI)

    Zayas, Jose R.; Johnson, Wesley D.

    2008-03-01T23:59:59.000Z

    In support of a Work-For-Other (WFO) agreement between the Wind Energy Technology Department at Sandia National Laboratories and 3TEX, one of the three Micon 65/13M wind turbines at the USDA Agriculture Research Service (ARS) center in Bushland, Texas, has been used to test a set of 9 meter wind turbine blades, manufactured by TPI composites using the 3TEX carbon material for the spar cap. Data collected from the test has been analyzed to evaluate both the aerodynamic performance and the structural response from the blades. The blades aerodynamic and structural performance, the meteorological inflow and the wind turbine structural response has been monitored with an array of 57 instruments: 15 to characterize the blades, 13 to characterize inflow, and 15 to characterize the time-varying state of the turbine. For the test, data was sampled at a rate of 40 Hz using the ATLAS II (Accurate GPS Time-Linked Data Acquisition System) data acquisition system. The system features a time-synchronized continuous data stream and telemetered data from the turbine rotor. This paper documents the instruments and infrastructure that have been developed to monitor these blades, turbines and inflow, as well as both modeling and field testing results.

  16. Height fluctuations in interacting dimers

    E-Print Network [OSTI]

    Alessandro Giuliani; Vieri Mastropietro; Fabio Lucio Toninelli

    2015-05-05T23:59:59.000Z

    We consider a non-integrable model for interacting dimers on the two-dimensional square lattice. Configurations are perfect matchings of $\\mathbb Z^2$, i.e. subsets of edges such that each vertex is covered exactly once ("close-packing" condition). Dimer configurations are in bijection with discrete height functions, defined on faces $\\boldsymbol{\\xi}$ of $\\mathbb Z^2$. The non-interacting model is "integrable" and solvable via Kasteleyn theory; it is known that all the moments of the height difference $h_{\\boldsymbol{\\xi}}-h_{\\boldsymbol{\\eta}}$ converge to those of the massless Gaussian Free Field (GFF), asymptotically as $|{\\boldsymbol{\\xi}}-{\\boldsymbol{\\eta}}|\\to \\infty$. We prove that the same holds for small non-zero interactions, as was conjectured in the theoretical physics literature. Remarkably, dimer-dimer correlation functions are instead not universal and decay with a critical exponent that depends on the interaction strength. Our proof is based on an exact representation of the model in terms of lattice interacting fermions, which are studied by constructive field theory methods. In the fermionic language, the height difference $h_{\\boldsymbol{\\xi}}-h_{\\boldsymbol{\\eta}}$ takes the form of a non-local operator, consisting of a sum of monomials along an {\\it arbitrary} path connecting $\\boldsymbol{\\xi}$ and $\\boldsymbol{\\eta}$. As in the non-interacting case, this path-independence plays a crucial role in the proof.

  17. Methods of making wind turbine rotor blades

    DOE Patents [OSTI]

    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

    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.

  18. Wind blade spar cap and method of making

    DOE Patents [OSTI]

    Mohamed, Mansour H. (Raleigh, NC)

    2008-05-27T23:59:59.000Z

    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.

  19. SNL Researchers Assess Wind Turbine Blade Inspection and Repair...

    Office of Environmental Management (EM)

    Researchers Assess Wind Turbine Blade Inspection and Repair Methods SNL Researchers Assess Wind Turbine Blade Inspection and Repair Methods May 18, 2015 - 5:32pm Addthis A picture...

  20. Methods and apparatus for rotor blade ice detection

    DOE Patents [OSTI]

    LeMieux, David Lawrence

    2006-08-08T23:59:59.000Z

    A method for detecting ice on a wind turbine having a rotor and one or more rotor blades each having blade roots includes monitoring meteorological conditions relating to icing conditions and monitoring one or more physical characteristics of the wind turbine in operation that vary in accordance with at least one of the mass of the one or more rotor blades or a mass imbalance between the rotor blades. The method also includes using the one or more monitored physical characteristics to determine whether a blade mass anomaly exists, determining whether the monitored meteorological conditions are consistent with blade icing; and signaling an icing-related blade mass anomaly when a blade mass anomaly is determined to exist and the monitored meteorological conditions are determined to be consistent with icing.

  1. Reduced Order Structural Modeling of Wind Turbine Blades

    E-Print Network [OSTI]

    Jonnalagadda, Yellavenkatasunil

    2011-10-21T23:59:59.000Z

    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...

  2. Wind Technology Testing Center Acquires New Blade Fatigue Test...

    Broader source: Energy.gov (indexed) [DOE]

    the American Recovery and Reinvestment Act, the WTTC is one of the largest blade test facilities in the world, testing some of the longest blades made today for the...

  3. Business expansion and lean transformation for helicopter blade shop

    E-Print Network [OSTI]

    Bar, S. Neil (Saumen Neil)

    2006-01-01T23:59:59.000Z

    Sikorsky Aircraft is undergoing a lean transformation as its helicopter blade line is relocated from Stratford to Site B. Value Stream Mapping is a vital tool to eliminate sources of waste in the existing blade shop and ...

  4. Vertical axis wind turbine with continuous blade angle adjustment

    E-Print Network [OSTI]

    Weiss, Samuel Bruce

    2010-01-01T23:59:59.000Z

    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 ...

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

    SciTech Connect (OSTI)

    Larwood, S.; Musial, W.

    2000-03-13T23:59:59.000Z

    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.

  6. Remote Monitoring of the Structural Health of Hydrokinetic Composite Turbine Blades

    SciTech Connect (OSTI)

    J.L. Rovey

    2012-09-21T23:59:59.000Z

    A health monitoring approach is investigated for hydrokinetic turbine blade applications. In-service monitoring is critical due to the difficult environment for blade inspection and the cost of inspection downtime. Composite blade designs have advantages that include long life in marine environments and great control over mechanical properties. Experimental strain characteristics are determined for static loads and free-vibration loads. These experiments are designed to simulate the dynamic characteristics of hydrokinetic turbine blades. Carbon/epoxy symmetric composite laminates are manufactured using an autoclave process. Four-layer composite beams, eight-layer composite beams, and two-dimensional eight-layer composite blades are instrumented for strain. Experimental results for strain measurements from electrical resistance gages are validated with theoretical characteristics obtained from in-house finite-element analysis for all sample cases. These preliminary tests on the composite samples show good correlation between experimental and finite-element strain results. A health monitoring system is proposed in which damage to a composite structure, e.g. delamination and fiber breakage, causes changes in the strain signature behavior. The system is based on embedded strain sensors and embedded motes in which strain information is demodulated for wireless transmission. In-service monitoring is critical due to the difficult environment for blade inspection and the cost of inspection downtime. Composite blade designs provide a medium for embedding sensors into the blades for in-situ health monitoring. The major challenge with in-situ health monitoring is transmission of sensor signals from the remote rotating reference frame of the blade to the system monitoring station. In the presented work, a novel system for relaying in-situ blade health measurements in hydrokinetic systems is described and demonstrated. An ultrasonic communication system is used to transmit sensor data underwater from the rotating frame of the blade to a fixed relay station. Data are then broadcast via radio waves to a remote monitoring station. Results indicate that the assembled system can transmit simulated sensor data with an accuracy of ±5% at a maximum sampling rate of 500 samples/sec. A power investigation of the transmitter within the blade shows that continuous max-sampling operation is only possible for short durations (~days), and is limited due to the capacity of the battery power source. However, intermittent sampling, with long periods between samples, allows for the system to last for very long durations (~years). Finally, because the data transmission system can operate at a high sampling rate for short durations or at a lower sampling rate/higher duty cycle for long durations, it is well-suited for short-term prototype and environmental testing, as well as long-term commercially-deployed hydrokinetic machines.

  7. Dual-Axis Resonance Testing of Wind Turbine Blades

    Energy Innovation Portal (Marketing Summaries) [EERE]

    2014-07-28T23:59:59.000Z

    Wind turbine blades must undergo strength and fatigue testing in order to be rated and marketed appropriately. Presently, wind turbine blades are fatigue-tested in the flapwise direction and in the edgewise direction independently. This testing involves placing the blades through 1 to 10 million or more load or fatigue cycles, which may take 3 to 12 months or more to complete for each tested direction. There is a need for blade testing techniques that are less expensive to use and require...

  8. Method and apparatus for reducing cleaning blade wear

    DOE Patents [OSTI]

    Grannes, Steven G. (St. Paul, MN); Rhoades, Charles A. (St. Paul, MN); Hebbie, Terry L. (Bloomington, MN)

    1992-01-01T23:59:59.000Z

    An improved cleaning blade construction (10) for eliminating erosion troughs (6) in the upper surface (15) of a cleaning blade member (14) by introducing pressurized fluid through a pressure manifold chamber (16) formed in the upper surface (15) of the cleaning blade member (14). The pressurized fluid will prevent carryback material (7) from passing through a wear groove (6) formed in the cleaning blade member.

  9. 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

  10. Selection of Wind Turbine Blade Materials for Fatigue Resistance

    E-Print Network [OSTI]

    Selection of Wind Turbine Blade Materials for Fatigue Resistance John Mandell Montana State center to center26 inch center to center #12;Blade Infusion L Lab InfusionLab Infusion #12;Schematic blade laminates Complex structured coupons with ply drops­ Complex structured coupons with ply drops

  11. AIAA980057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS

    E-Print Network [OSTI]

    Sweetman, Bert

    AIAA­98­0057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS: PARAMETRIC STUDY WITH MULTIPLE that is most useful in estimating fatigue loads on wind turbine blades. The histograms of rainflow counted turbulence measures---can be used to estimate fatigue loads on wind turbine blades. We first de­ scribe

  12. Ris-R-Report Load Consequences when Sweeping Blades -

    E-Print Network [OSTI]

    reference wind turbine model is used to investigate the influence of different blade sweep curves studies regarding swept wind turbine blades for pitch controlled turbines have indicated that a flapRisø-R-Report Load Consequences when Sweeping Blades - A Case Study of a 5 MW Pitch Controlled Wind

  13. Ultimate strength of a large wind turbine blade

    E-Print Network [OSTI]

    Ultimate strength of a large wind turbine blade Find Mølholt Jensen Risø-PhD-34(EN) ISBN 978 2008 #12;#12;Author: Find Mølholt Jensen Title: Ultimate strength of a large wind turbine blade contains a study of the structural static strength of wind turbine blades loaded in flap-wise direction

  14. Parametric Study of Turbine Blade Internal Cooling and Film Cooling

    E-Print Network [OSTI]

    Rallabandi, Akhilesh P.

    2010-10-12T23:59:59.000Z

    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...

  15. Design of heterogeneous turbine blade Xiaoping Qian, Deba Dutta*

    E-Print Network [OSTI]

    Qian, Xiaoping

    Design of heterogeneous turbine blade Xiaoping Qian, Deba Dutta* Department of Mechanical in turbine drivers push the material capabilities of turbine blades to the limit. The recent development of heterogeneous objects by layered manufacturing offers new potentials for the turbine blades. In heterogeneous

  16. 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

  17. MELE: Maximum Entropy Leuven Estimators

    E-Print Network [OSTI]

    Paris, Quirino

    2001-01-01T23:59:59.000Z

    of the Generalized Maximum Entropy Estimator of the Generaland Douglas Miller, Maximum Entropy Econometrics, Wiley andCalifornia Davis MELE: Maximum Entropy Leuven Estimators by

  18. Maximum Parsimony and Maximum Likelihood Methods Comparisons and Bootstrap Tests

    E-Print Network [OSTI]

    Qiu, Weigang

    Maximum Parsimony and Maximum Likelihood Methods Comparisons and Bootstrap Tests Character Likelihood Methods Comparisons and Bootstrap Tests Character Reconstruction PHYLIP and T-REX Exercises Outline 1 Maximum Parsimony and Maximum Likelihood 2 Methods Comparisons and Bootstrap Tests 3 Character

  19. Maximum Entropy Correlated Equilibria

    E-Print Network [OSTI]

    Ortiz, Luis E.

    2006-03-20T23:59:59.000Z

    We study maximum entropy correlated equilibria in (multi-player)games and provide two gradient-based algorithms that are guaranteedto converge to such equilibria. Although we do not provideconvergence rates for these ...

  20. Blade reliability collaborative : collection of defect, damage and repair data.

    SciTech Connect (OSTI)

    Ashwill, Thomas D.; Ogilvie, Alistair B.; Paquette, Joshua A.

    2013-04-01T23:59:59.000Z

    The Blade Reliability Collaborative (BRC) was started by the Wind Energy Technologies Department of Sandia National Laboratories and DOE in 2010 with the goal of gaining insight into planned and unplanned O&M issues associated with wind turbine blades. A significant part of BRC is the Blade Defect, Damage and Repair Survey task, which will gather data from blade manufacturers, service companies, operators and prior studies to determine details about the largest sources of blade unreliability. This report summarizes the initial findings from this work.

  1. Turbine blade squealer tip rail with fence members

    DOE Patents [OSTI]

    Little, David A

    2012-11-20T23:59:59.000Z

    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.

  2. Estimating vehicle height using homographic projections

    DOE Patents [OSTI]

    Cunningham, Mark F; Fabris, Lorenzo; Gee, Timothy F; Ghebretati, Jr., Frezghi H; Goddard, James S; Karnowski, Thomas P; Ziock, Klaus-peter

    2013-07-16T23:59:59.000Z

    Multiple homography transformations corresponding to different heights are generated in the field of view. A group of salient points within a common estimated height range is identified in a time series of video images of a moving object. Inter-salient point distances are measured for the group of salient points under the multiple homography transformations corresponding to the different heights. Variations in the inter-salient point distances under the multiple homography transformations are compared. The height of the group of salient points is estimated to be the height corresponding to the homography transformation that minimizes the variations.

  3. Maximum output at minimum cost

    E-Print Network [OSTI]

    Firestone, Jeremy

    University) + FFA-W3 Material Preimpregnated epoxy glass fiber + carbon fiber Total blade weight 5,800 kg.0 MW wind turbine generator uses the "total lightning protection" system, in accordance with standard working life of the turbine. Gamesa WindNet® The new generation SCADA System (a wind farm control system

  4. Tip cap for a turbine rotor blade

    DOE Patents [OSTI]

    Kimmel, Keith D

    2014-03-25T23:59:59.000Z

    A turbine rotor blade with a spar and shell construction, and a tip cap that includes a row of lugs extending from a bottom side that form dovetail grooves that engage with similar shaped lugs and grooves on a tip end of the spar to secure the tip cap to the spar against radial displacement. The lug on the trailing edge end of the tip cap is aligned perpendicular to a chordwise line of the blade in the trailing edge region in order to minimize stress due to the lugs wanting to bend under high centrifugal loads. A two piece tip cap with lugs at different angles will reduce the bending stress even more.

  5. Turbine blade with contoured chamfered squealer tip

    DOE Patents [OSTI]

    Lee, Ching-Pang

    2014-12-30T23:59:59.000Z

    A squealer tip formed from a pressure side tip wall and a suction side tip wall extending radially outward from a tip of the turbine blade is disclosed. The pressure and suction side tip walls may be positioned along the pressure sidewall and the suction sidewall of the turbine blade, respectively. The pressure side tip wall may include a chamfered leading edge with film cooling holes having exhaust outlets positioned therein. An axially extending tip wall may be formed from at least two outer linear surfaces joined together at an intersection forming a concave axially extending tip wall. The axially extending tip wall may include a convex inner surface forming a radially outer end to an inner cavity forming a cooling system. The cooling system may include one or more film cooling holes in the axially extending tip wall proximate to the suction sidewall, which promotes increased cooling at the pressure and suction sidewalls.

  6. Prediction of stochastic blade loads for three-bladed, rigid-hub rotors

    SciTech Connect (OSTI)

    Wright, A.D.; Weber, T.L.; Thresher, R.W.; Butterfield, C.P.

    1989-11-01T23:59:59.000Z

    Accurately predicting wind turbine blade loads and response is important for the design of future wind turbines. The need to include turbulent wind inputs in structural dynamics models is widely recognized. In this paper, the Force and Loads Analysis Program (FLAP) code will be used to predict turbulence-induced bending moments for the SERI Combined Experiment rotor blade and the Howden 330-kW blade. FLAP code predictions will be compared to the power spectra of measured blade-bending moments. Two methods will be used to generate turbulent wind inputs to FLAP: a theoretical simulation: the Pacific Northwest Laboratories (PNL) simulation theory; and measured wind-speed data taken from an array of anemometers upwind of the turbine. Turbulent wind-speed time series are input to FLAP for both methods outlined above. Power spectra of predicted flap-bending moments are compared to measured results for different wind conditions. Conclusions are also drawn as to the ability of the turbulence simulation models to provide accurate wind input to FLAP and to FLAP's ability to accurately simulate blade response to turbulence. Finally, suggestions are made as to needed improvements in the theoretical model. 11 refs., 8 figs.

  7. Comparison of Blade-Strike Modeling Results with Empirical Data

    SciTech Connect (OSTI)

    Carlson, Thomas J.; Ploskey, Gene R.

    2004-05-06T23:59:59.000Z

    This study is the initial stage of further investigation into the dynamics of injury to fish during passage through a turbine runner. As part of the study, Pacific Northwest National Laboratory (PNNL) estimated the probability of blade strike, and associated injury, as a function of fish length and turbine operating geometry at two adjacent turbines in Powerhouse 1 of Bonneville Dam. Units 5 and 6 had identical intakes, stay vanes, wicket gates, and draft tubes, but Unit 6 had a new runner and curved discharge ring to minimize gaps between the runner hub and blades and between the blade tips and discharge ring. We used a mathematical model to predict blade strike associated with two Kaplan turbines and compared results with empirical data from biological tests conducted in 1999 and 2000. Blade-strike models take into consideration the geometry of the turbine blades and discharges as well as fish length, orientation, and distribution along the runner.

  8. Micromachined cutting blade formed from {211}-oriented silicon

    DOE Patents [OSTI]

    Fleming, James G. (Albuquerque, NM); Fleming, legal representative, Carol (Burbank, CA); Sniegowski, Jeffry J. (Tijeras, NM); Montague, Stephen (Albuquerque, NM)

    2011-08-09T23:59:59.000Z

    A cutting blade is disclosed fabricated of micromachined silicon. The cutting blade utilizes a monocrystalline silicon substrate having a {211} crystalline orientation to form one or more cutting edges that are defined by the intersection of {211} crystalline planes of silicon with {111} crystalline planes of silicon. This results in a cutting blade which has a shallow cutting-edge angle .theta. of 19.5.degree.. The micromachined cutting blade can be formed using an anisotropic wet etching process which substantially terminates etching upon reaching the {111} crystalline planes of silicon. This allows multiple blades to be batch fabricated on a common substrate and separated for packaging and use. The micromachined cutting blade, which can be mounted to a handle in tension and optionally coated for increased wear resistance and biocompatibility, has multiple applications including eye surgery (LASIK procedure).

  9. Sweep-twist adaptive rotor blade : final project report.

    SciTech Connect (OSTI)

    Ashwill, Thomas D.

    2010-02-01T23:59:59.000Z

    Knight & Carver was contracted by Sandia National Laboratories to develop a Sweep Twist Adaptive Rotor (STAR) blade that reduced operating loads, thereby allowing a larger, more productive rotor. The blade design used outer blade sweep to create twist coupling without angled fiber. Knight & Carver successfully designed, fabricated, tested and evaluated STAR prototype blades. Through laboratory and field tests, Knight & Carver showed the STAR blade met the engineering design criteria and economic goals for the program. A STAR prototype was successfully tested in Tehachapi during 2008 and a large data set was collected to support engineering and commercial development of the technology. This report documents the methodology used to develop the STAR blade design and reviews the approach used for laboratory and field testing. The effort demonstrated that STAR technology can provide significantly greater energy capture without higher operating loads on the turbine.

  10. Predicting Maximum Tree Heights and Other Traits from Allometric Scaling and Resource Limitations

    E-Print Network [OSTI]

    Kempes, Chris Poling

    Terrestrial vegetation plays a central role in regulating the carbon and water cycles, and adjusting planetary albedo. As such, a clear understanding and accurate characterization of vegetation dynamics is critical to ...

  11. Property:Maximum Wave Height(m) at Wave Period(s) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid JumpEligSysSize JumpTechDsc Jump to: navigation,

  12. Turbine blade having a constant thickness airfoil skin

    DOE Patents [OSTI]

    Marra, John J

    2012-10-23T23:59:59.000Z

    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.

  13. Evaluation of the stepped blade using the pressuremeter

    E-Print Network [OSTI]

    Gan, Kuat Chin

    1987-01-01T23:59:59.000Z

    contribute to the fact that the soil pressure versus blade thickness curve exhibits a peak in certain soils Steppe d blade tests, preboring pressur?ineter tests and self-boring pr&ssiirem?- ter tests w& re performed at two overconsolidated clay sites arid... two san&i sites In th?clay, the stepped blade values of It, w& re on the av& rage 3 to 4 tim?s larger than tlie prebonng pressuremeter and the self-boring pressuremeter values ol' Ir In the sand, the st& pped blade values of Iv?compared well...

  14. Utilization of localized panel resonant behavior in wind turbine blades.

    SciTech Connect (OSTI)

    Griffith, Daniel Todd

    2010-11-01T23:59:59.000Z

    The shear webs and laminates of core panels of wind turbine blades must be designed to avoid panel buckling while minimizing blade weight. Typically, buckling resistance is evaluated by consideration of the load-deflection behavior of a blade using finite element analysis (FEA) or full-scale static loading of a blade to failure under a simulated extreme loading condition. This paper examines an alternative means for evaluating blade buckling resistance using non-destructive modal tests or FEA. In addition, panel resonances can be utilized for structural health monitoring by observing changes in the modal parameters of these panel resonances, which are only active in a portion of the blade that is susceptible to failure. Additionally, panel resonances are considered for updating of panel laminate model parameters by correlation with test data. During blade modal tests conducted at Sandia Labs, a series of panel modes with increasing complexity was observed. This paper reports on the findings of these tests, describes potential ways to utilize panel resonances for blade evaluation, health monitoring, and design, and reports recent numerical results to evaluate panel resonances for use in blade structural health assessment.

  15. Sandia National Laboratories: blade NDI reference sample library

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NDI reference sample library Sandia Participated in AMII to Support American-Made Wind-Turbine Blades On December 3, 2014, in Computational Modeling & Simulation, Energy, Materials...

  16. Sandia National Laboratories: wind-turbine blade construction

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    wind-turbine blade construction Composite-Materials Fatigue Database Updated On January 22, 2014, in Energy, Materials Science, News, News & Events, Partnership, Renewable Energy,...

  17. SciTech Connect: Blade Testing Trends (Presentation)

    Office of Scientific and Technical Information (OSTI)

    Org: Other Non-EERE Country of Publication: United States Language: English Subject: 17 WIND ENERGY BLADE TESTING; TRENDS; BIAXIAL TESTING; NATIONAL WIND TECHNOLOGY CENTER; NWTC;...

  18. aerodynamic blade optimisation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The aerodynamic performance of an existing wind turbine blade optimised for low wind speed conditions (more) Pierce, Warrick Taite 2009-01-01 4 Aerodynamic optimisation of a...

  19. Sandia National Laboratories: functional wind-turbine blade scaling

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    wind-turbine blade scaling National Rotor Testbed Functional Scaling Presented at American Institute of Aeronautics and Astronautics 2014 Scitech On April 15, 2014, in Energy,...

  20. DOE's New Large Blade Test Facility in Massachusetts Completes...

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

    (WTTC), in Boston, Massachusetts, has come up to full speed testing the long wind turbine blades produced for today's larger wind turbines. Constructed with a combination of...

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

    E-Print Network [OSTI]

    Sidwell, Carroll Vincent, 1972-

    2004-01-01T23:59:59.000Z

    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 ...

  2. A RIGOROUS, ENGINEER-FRIENDLY APPROACH FOR MODELING REALISTIC, COMPOSITE ROTOR BLADES

    E-Print Network [OSTI]

    Yu, Wenbin

    structures of the type encountered in wind turbine blades, helicopter rotor blades, and the like such as wind turbine blades lead to a splitting of the problem into a (usually) linear, two-dimensional cross

  3. DAMAGE DETECTION METHODS ON WIND TURBINE BLADE TESTING WITH WIRED AND WIRELESS ACCELEROMETER SENSORS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    DAMAGE DETECTION METHODS ON WIND TURBINE BLADE TESTING WITH WIRED AND WIRELESS ACCELEROMETER turbine blade. We compare the data collected from the wireless sensors against wired sensors for nonstationary blade excitations. KEYWORDS : Structural Health Monitoring, Damage Detection, Wind Turbine

  4. The SNL100-03 Blade: Design Studies with Flatback Airfoils for the Sandia 100-meter Blade.

    SciTech Connect (OSTI)

    Griffith, Daniel; Richards, Phillip William

    2014-09-01T23:59:59.000Z

    A series of design studies were performed to inv estigate the effects of flatback airfoils on blade performance and weight for large blades using the Sandi a 100-meter blade designs as a starting point. As part of the study, the effects of varying the blade slenderness on blade structural performance was investigated. The advantages and disadvantages of blad e slenderness with respect to tip deflection, flap- wise & edge-wise fatigue resistance, panel buckling capacity, flutter speed, manufacturing labor content, blade total weight, and aerodynamic design load magn itude are quantified. Following these design studies, a final blade design (SNL100-03) was prod uced, which was based on a highly slender design using flatback airfoils. The SNL100-03 design with flatback airfoils has weight of 49 tons, which is about 16% decrease from its SNL100-02 predecessor that used conventional sharp trailing edge airfoils. Although not systematically optimized, the SNL100 -03 design study provides an assessment of and insight into the benefits of flatback airfoils for la rge blades as well as insights into the limits or negative consequences of high blade slenderness resulting from a highly slender SNL100-03 planform as was chosen in the final design definition. This docum ent also provides a description of the final SNL100-03 design definition and is intended to be a companion document to the distribution of the NuMAD blade model files for SNL100-03, which are made publicly available. A summary of the major findings of the Sandia 100-meter blade development program, from the initial SNL100-00 baseline blade through the fourth SNL100-03 blade study, is provided. This summary includes the major findings and outcomes of blade d esign studies, pathways to mitigate the identified large blade design drivers, and tool development that were produced over the course of this five-year research program. A summary of large blade tec hnology needs and research opportunities is also presented.

  5. Raman lidar/AERI PBL Height Product

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Ferrare, Richard

    Planetary Boundary Layer (PBL) heights have been computed using potential temperature profiles derived from Raman lidar and AERI measurements. Raman lidar measurements of the rotational Raman scattering from nitrogen and oxygen are used to derive vertical profiles of potential temperature. AERI measurements of downwelling radiance are used in a physical retrieval approach (Smith et al. 1999, Feltz et al. 1998) to derive profiles of temperature and water vapor. The Raman lidar and AERI potential temperature profiles are merged to create a single potential temperature profile for computing PBL heights. PBL heights were derived from these merged potential temperature profiles using a modified Heffter (1980) technique that was tailored to the SGP site (Della Monache et al., 2004). PBL heights were computed on an hourly basis for the period January 1, 2009 through December 31, 2011. These heights are provided as meters above ground level.

  6. university-logo Maximum likelihood

    E-Print Network [OSTI]

    McCullagh, Peter

    university-logo Maximum likelihood Applications and examples REML and residual likelihood Peter McCullagh REML #12;university-logo Maximum likelihood Applications and examples JAN: Some personal remarks... IC #12;university-logo Maximum likelihood Applications and examples Outline 1 Maximum likelihood REML

  7. Dynamic stall on wind turbine blades

    SciTech Connect (OSTI)

    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

    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.

  8. Multiple piece turbine blade/vane

    DOE Patents [OSTI]

    Kimmel, Keith D

    2013-02-05T23:59:59.000Z

    An air cooled turbine blade or vane of a spar and shell construction with the shell made from a high temperature resistant material that must be formed from an EDM process. The shell and the spar both have a number of hooks extending in a spanwise direction and forming a contact surface that is slanted such that a contact force increases as the engaging hooks move away from one another. The slanted contact surfaces on the hooks provides for an better seal and allows for twisting between the shell and the spar while maintaining a tight fit.

  9. Sandia Energy - Rotor Blade Sensors and Instrumentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol Home Distribution GridDocuments Home Stationary PowerResearchRisk andBlade

  10. EVALUATION OF HAND LAY-UP AND RESIN TRANSFER MOLDING IN COMPOSITE WIND TURBINE BLADE MANUFACTURING

    E-Print Network [OSTI]

    EVALUATION OF HAND LAY-UP AND RESIN TRANSFER MOLDING IN COMPOSITE WIND TURBINE BLADE MANUFACTURING..........................................................................................................1 Hand Lay-up in Turbine Blade Fabrication

  11. Load Alleviation on Wind Turbine Blades using Variable Airfoil Geometry

    E-Print Network [OSTI]

    Load Alleviation on Wind Turbine Blades using Variable Airfoil Geometry Peter Bjørn Andersen, Mac Loads, Trailing Edge Flaps, PID control, Signal Noise. 1 Introduction Wind turbine blades are subject to 40% when signal noise is added to the control. Keywords: Wind Turbine, Load Alleviation, Fatigue

  12. Vortex Lattice Modelling of Winglets on Wind Turbine Blades

    E-Print Network [OSTI]

    Vortex Lattice Modelling of Winglets on Wind Turbine Blades Mads Døssing Risø-R-1621(EN) Risø Title: Vortex Lattice Modelling of Winglets on Wind Turbine Blades Departments: Wind Energy Department turbines can be increased by the use of winglets without increasing the swept area. This makes them

  13. Height modification in grain sorghum lines homozygous for four major height genes

    E-Print Network [OSTI]

    Thompson, Tommy Earl

    1970-01-01T23:59:59.000Z

    HEIGHT MODIFICATION IN GRAIN SORGHUM LINES HOMOZYGOUS FOR FOUR MAJOR HEIGHT GENES A Thesis by TOMMY EARL THOMPSON Approved as to style and content by: (Chairman of~Gommittge) ead o Department) c~~' (Member) r/ ?. cl + ' r EM '7Z' (Member...) January 1970 95Z941 111 AB S T RA C T Height "!odification i i Grain Sorghum Lines Homozygous for Four Flajor Height Genes. (January, 1970) Tommy E. I'hompson, B. S. , Te;&as ASFI University Directed by: Dr. K. F. Schertz Height in grain sorghum...

  14. Wind turbine blade testing system using base excitation

    DOE Patents [OSTI]

    Cotrell, Jason; Thresher, Robert; Lambert, Scott; Hughes, Scott; Johnson, Jay

    2014-03-25T23:59:59.000Z

    An apparatus (500) for fatigue testing elongate test articles (404) including wind turbine blades through forced or resonant excitation of the base (406) of the test articles (404). The apparatus (500) includes a testing platform or foundation (402). A blade support (410) is provided for retaining or supporting a base (406) of an elongate test article (404), and the blade support (410) is pivotally mounted on the testing platform (402) with at least two degrees of freedom of motion relative to the testing platform (402). An excitation input assembly (540) is interconnected with the blade support (410) and includes first and second actuators (444, 446, 541) that act to concurrently apply forces or loads to the blade support (410). The actuator forces are cyclically applied in first and second transverse directions. The test article (404) responds to shaking of its base (406) by oscillating in two, transverse directions (505, 507).

  15. Definition of a 5MW/61.5m wind turbine blade reference model.

    SciTech Connect (OSTI)

    Resor, Brian Ray

    2013-04-01T23:59:59.000Z

    A basic structural concept of the blade design that is associated with the frequently utilized %E2%80%9CNREL offshore 5-MW baseline wind turbine%E2%80%9D is needed for studies involving blade structural design and blade structural design tools. The blade structural design documented in this report represents a concept that meets basic design criteria set forth by IEC standards for the onshore turbine. The design documented in this report is not a fully vetted blade design which is ready for manufacture. The intent of the structural concept described by this report is to provide a good starting point for more detailed and targeted investigations such as blade design optimization, blade design tool verification, blade materials and structures investigations, and blade design standards evaluation. This report documents the information used to create the current model as well as the analyses used to verify that the blade structural performance meets reasonable blade design criteria.

  16. Aeroelastic tailoring in wind-turbine blade applications

    SciTech Connect (OSTI)

    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

    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.

  17. A surface definition code for turbine blade surfaces

    SciTech Connect (OSTI)

    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

    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.

  18. ACTIVE CONTROL OF FLOW SEPARATION AND STRUCTURAL VIBRATIONS OF WIND TURBINE BLADES

    E-Print Network [OSTI]

    Salama, Khaled

    ACTIVE CONTROL OF FLOW SEPARATION AND STRUCTURAL VIBRATIONS OF WIND TURBINE BLADES Sponsor: Ney actuators embedded inside the wind turbine blade to provide an efficient, rapid and compact means to alter the ability to shed excess wind loads off the blade. 3. Reduce vibration in the turbine blades by selectively

  19. User scripting on Android using BladeDroid Ravi Bhoraskar , Dominic Langenegger

    E-Print Network [OSTI]

    Ernst, Michael

    . In this paper, we introduce BladeDroid, a system that supports custom user scripts, which we call "BladesUser scripting on Android using BladeDroid Ravi Bhoraskar , Dominic Langenegger , Pingyang He. This paper presents BladeDroid, a system enabling user customization of mobile applications, using a novel

  20. Medial design of blades for hydroelectric turbines and ship propellers M. Rossgatterera

    E-Print Network [OSTI]

    Jüttler, Bert

    Medial design of blades for hydroelectric turbines and ship propellers M. Rossgatterera , B. J Abstract We present a method for constructing blades of hydroelectric turbines and ship propellers based. Keywords: CAD-model, B-spline representation, hydroelectric turbine blade, propeller blade, medial axis

  1. Turbine blade with spar and shell

    DOE Patents [OSTI]

    Davies, Daniel O. (Palm City, FL); Peterson, Ross H. (Loxahatchee, FL)

    2012-04-24T23:59:59.000Z

    A turbine blade with a spar and shell construction in which the spar and the shell are both secured within two platform halves. The spar and the shell each include outward extending ledges on the bottom ends that fit within grooves formed on the inner sides of the platform halves to secure the spar and the shell against radial movement when the two platform halves are joined. The shell is also secured to the spar by hooks extending from the shell that slide into grooves formed on the outer surface of the spar. The hooks form a serpentine flow cooling passage between the shell and the spar. The spar includes cooling holes on the lower end in the leading edge region to discharge cooling air supplied through the platform root and into the leading edge cooling channel.

  2. Gas turbine blade with intra-span snubber

    DOE Patents [OSTI]

    Merrill, Gary B.; Mayer, Clinton

    2014-07-29T23:59:59.000Z

    A gas turbine blade (10) including a hollow mid-span snubber (16). The snubber is affixed to the airfoil portion (14) of the blade by a fastener (20) passing through an opening (24) cast into the surface (22) of the blade. The opening is defined during an investment casting process by a ceramic pedestal (38) which is positioned between a ceramic core (32) and a surrounding ceramic casting shell (48). The pedestal provides mechanical support for the ceramic core during both wax and molten metal injection steps of the investment casting process.

  3. PSR J0737-3039B: A PROBE OF RADIO PULSAR EMISSION HEIGHTS

    SciTech Connect (OSTI)

    Perera, B. B. P.; McLaughlin, M. A. [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Lomiashvili, D.; Gourgouliatos, K. N.; Lyutikov, M. [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States)

    2012-05-10T23:59:59.000Z

    In the double pulsar system PSR J0737-3039A/B, the strong wind produced by pulsar A distorts the magnetosphere of pulsar B. The influence of these distortions on the orbital-dependent emission properties of pulsar B can be used to determine the location of the coherent radio emission generation region in the pulsar magnetosphere. Using a model of the wind-distorted magnetosphere of pulsar B and the well-defined geometrical parameters of the system, we determine the minimum emission height to be {approx}20R{sub NS} in the two bright orbital longitude regions. We can determine the maximum emission height by accounting for the amount of deflection of the polar field line with respect to the magnetic axis using the analytical magnetic reconnection model of Dungey and the semi-empirical numerical model of Tsyganenko. Both of these models estimate the maximum emission height to be {approx}2500R{sub NS}. The minimum and maximum emission heights we calculate are consistent with those estimated for normal isolated pulsars.

  4. The height of watermelons with wall

    E-Print Network [OSTI]

    Thomas Feierl

    2012-04-11T23:59:59.000Z

    We derive asymptotics for the moments as well as the weak limit of the height distribution of watermelons with p branches with wall. This generalises a famous result of de Bruijn, Knuth and Rice on the average height of planted plane trees, and results by Fulmek and Katori et al. on the expected value, respectively the higher moments, of the height distribution of watermelons with two branches. The asymptotics for the moments depend on the analytic behaviour of certain multidimensional Dirichlet series. In order to obtain this information we prove a reciprocity relation satisfied by the derivatives of one of Jacobi's theta functions, which generalises the well known reciprocity law for Jacobi's theta functions.

  5. Active Aerodynamic Blade Distributed Flap Control Design Procedure

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Active Aerodynamic Blade Distributed Flap Control Design Procedure for Load Reduction on the UpWind 5MW Wind Turbine David G. Wilson , Brian R. Resor , Dale E. Berg ...

  6. Development of Glassy Carbon Blade for LHC Fast Vacuum Valve

    E-Print Network [OSTI]

    Coly, P

    2012-01-01T23:59:59.000Z

    An unexpected gas inrush in a vacuum chamber leads to the development of a fast pressure wave. It carries small particles that can compromise functionality of sensitive machine systems such as the RF cavities or kickers. In the LHC machine, it has been proposed to protect this sensitive equipment by the installation of fast vacuum valves. The main requirements for the fast valves and in particular for the blade are: fast closure in the 20 ms range, high transparency and melting temperature in case of closure with beam in, dust free material to not contaminate sensitive adjacent elements, and last but not least vacuum compatibility and adequate leak tightness across the blade. In this paper, different designs based on a vitreous carbon blade are presented and a solution is proposed. The main reasons for this material choice are given. The mechanical study of the blade behaviour under dynamic forces is shown.

  7. Lean implementation across value stream in main rotor blade area

    E-Print Network [OSTI]

    Phoenix, Casey J. (Casey John)

    2007-01-01T23:59:59.000Z

    The primary goal for this project was to help expand the existing capability of Sikorsky's main rotor blade business from raw material (titanium) through final assembly. The project helped to facilitate the ongoing lean ...

  8. Aerodynamic testing of a rotating wind turbine blade

    SciTech Connect (OSTI)

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

    1990-01-01T23:59:59.000Z

    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.

  9. SHM of wind turbine blades using piezoelectric active-sensors

    SciTech Connect (OSTI)

    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

    2010-01-01T23:59:59.000Z

    This paper presents a variety of structural health monitoring (SHM) techniques, based on the use of piezoelectric active-sensors, used to determine the structural integrity of wind turbine blades. Specifically, Lamb wave propagations, frequency response functions, and time series based methods are utilized to estimate the condition of wind turbine blades. For experiments, a 1m section of a 9m CX100 blade is used. Overall, these three methods yielded a sufficient damage detection capability to warrant further investigation into field deployment. A full-scale fatigue test of a CX-100 wind turbine blade is also conducted. This paper summarizes considerations needed to design such SHM systems, experimental procedures and results, and practical implementation issues that can be used as guidelines for future investigations.

  10. Propeller blade stress estimates using lifting line theory

    E-Print Network [OSTI]

    Epps, Brenden P.

    OpenProp, an open-source computational tool for the design and analysis of propellers and horizontal-axis turbines, is extended to provide estimates of normal stresses in the blades for both on- and off-design operating ...

  11. CX-100 and TX-100 blade field tests.

    SciTech Connect (OSTI)

    Holman, Adam (USDA-Agriculture Research Service, Bushland, TX); Jones, Perry L.; Zayas, Jose R.

    2005-12-01T23:59:59.000Z

    In support of the DOE Low Wind Speed Turbine (LWST) program two of the three Micon 65/13M wind turbines at the USDA Agricultural Research Service (ARS) center in Bushland, Texas will be used to test two sets of experimental blades, the CX-100 and TX-100. The blade aerodynamic and structural characterization, meteorological inflow and wind turbine structural response will be monitored with an array of 75 instruments: 33 to characterize the blades, 15 to characterize the inflow, and 27 to characterize the time-varying state of the turbine. For both tests, data will be sampled at a rate of 30 Hz using the ATLAS II (Accurate GPS Time-Linked Data Acquisition System) data acquisition system. The system features a time-synchronized continuous data stream and telemetered data from the turbine rotor. This paper documents the instruments and infrastructure that have been developed to monitor these blades, turbines and inflow.

  12. Blade Energy Partners STW Water Process & Technologies SMU Cox...

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

    Blade Energy Partners STW Water Process & Technologies SMU Cox Executive Education AltaRock Energy, Inc. SedHeat Tranter, Inc. Registration and event details: http:smu.edu...

  13. Development of a morphing helicopter blade with electrochemical actuators

    E-Print Network [OSTI]

    Tubilla Kuri, Fernando

    2007-01-01T23:59:59.000Z

    The use of the expansion of electrochemical cells, upon ion intercalation, for the development of a morphing helicopter blade is explored. Using commercially available lithium-ion batteries as demostrators of the technology, ...

  14. Experimental Investigation of Film Cooling Effectiveness on Gas Turbine Blades

    E-Print Network [OSTI]

    Li, Shiou-Jiuan

    2012-12-07T23:59:59.000Z

    . 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...

  15. Passive aeroelastic tailoring of wind turbine blades : a numerical analysis

    E-Print Network [OSTI]

    Deilmann, Christian

    2009-01-01T23:59:59.000Z

    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 ...

  16. Determining effects of turbine blades on fluid motion

    DOE Patents [OSTI]

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

    2011-05-31T23:59:59.000Z

    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.

  17. Determining effects of turbine blades on fluid motion

    DOE Patents [OSTI]

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

    2012-05-01T23:59:59.000Z

    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.

  18. Height and width of superatomic Boolean algebras

    E-Print Network [OSTI]

    Roitman, Judith A.

    1985-05-02T23:59:59.000Z

    PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY Volume 94, Number 1, May 1985 HEIGHT AND WIDTH OF SUPERATOMIC BOOLEAN ALGEBRAS JUDY ROITMAN1 Abstract. Cantor-Bendixson height and width of superatomic Boolean algebras is investigated and it is shown.../Ja), and define the Cantor- Bendixson width of X, wd^), to be the supremum of all wda( X). An sBa X is (a) K-thin iff wd( X) = k. (Note: thin = w-thin.) (b) K-thin-thick iff wda(A') = k for a < k and wdK(X) = k+. (Note: thin-thick = to,-thin-thick + Just's thin...

  19. Architecture TAKING ARCHITECTURE TO NEW HEIGHTS

    E-Print Network [OSTI]

    McConnell, Terry

    School of Architecture #12;TAKING ARCHITECTURE TO NEW HEIGHTS This is a time of tremendous momentum at the School of Architecture. Looking ahead, we have the unique opportunity to build on our strengths immediate and long term, and enable us to stake our ground as one of the country's premier architecture

  20. Achieve maximum application availability and

    E-Print Network [OSTI]

    Bernstein, Phil

    Highlights Achieve maximum application availability and data protection using SQL Server AlwaysOn and other high availability features Reduce planned downtime significantly with SQL Server on Windows and management of high availability and disaster recovery using integrated tools Achieve maximum application

  1. Original article Restricted maximum likelihood

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Original article Restricted maximum likelihood estimation of covariances in sparse linear models on the simplex algorithm of Nelder and Mead [40]. Kovac [29] made modifications that turned it into a stable

  2. Blade platform seal for ceramic/metal rotor assembly

    DOE Patents [OSTI]

    Wertz, John L. (Indianapolis, IN)

    1982-01-01T23:59:59.000Z

    A combination ceramic and metal turbine rotor for use in high temperature gas turbine engines includes a metal rotor disc having a rim with a plurality of circumferentially spaced blade root retention slots therein to receive a plurality of ceramic blades, each including side platform segments thereon and a dovetail configured root slidably received in one of the slots. Adjacent ones of the platform segments including edge portions thereon closely spaced when the blades are assembled to form expansion gaps in an annular flow surface for gas passage through the blades and wherein the assembly further includes a plurality of unitary seal members on the rotor connected to its rim and each including a plurality of spaced, axially extending, flexible fingers that underlie and conform to the edge portions of the platform segments and which are operative at turbine operating temperatures and speeds to distribute loading on the platform segments as the fingers are seated against the underside of the blade platforms to seal the gaps without undesirably stressing thin web ceramic sections of the platform.

  3. Incipient Crack Detection in Composite Wind Turbine Blades

    SciTech Connect (OSTI)

    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

    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.

  4. Near wall cooling for a highly tapered turbine blade

    SciTech Connect (OSTI)

    Liang, George (Palm City, FL)

    2011-03-08T23:59:59.000Z

    A turbine blade having a pressure sidewall and a suction sidewall connected at chordally spaced leading and trailing edges to define a cooling cavity. Pressure and suction side inner walls extend radially within the cooling cavity and define pressure and suction side near wall chambers. A plurality of mid-chord channels extend radially from a radially intermediate location on the blade to a tip passage at the blade tip for connecting the pressure side and suction side near wall chambers in fluid communication with the tip passage. In addition, radially extending leading edge and trailing edge flow channels are located adjacent to the leading and trailing edges, respectively, and cooling fluid flows in a triple-pass serpentine path as it flows through the leading edge flow channel, the near wall chambers and the trailing edge flow channel.

  5. Photoelastic stress analysis on a Phoenix 7. 9-meter blade

    SciTech Connect (OSTI)

    Musial, W.D.; Jenks, M.D.; Osgood, R.M.; Johnson, J.A.

    1991-10-01T23:59:59.000Z

    Photoelastic tests were conducted on the Phoenix 7.9-meter blade to develop the basic methodology for locating critical strain areas on full-scale composite structures. Under relatively low elastic loading the strain fields over various regions on the blade planform were documented with 35mm photographs under different loading conditions at the Solar Energy Research Institute (SERI) Structural Test Facility (STF). Strain concentrations were easily located and quantified. Principal strain magnitudes and directions were determined at the highest strain areas using separator gages. Results were compared to measured operating loads. This experiment demonstrated the value of experimental stress analysis using the photoelastic technique for the evaluation of composite blade designs. 9 refs., 6 figs., 3 tabs.

  6. Adaptor assembly for coupling turbine blades to rotor disks

    SciTech Connect (OSTI)

    Delvaux, John McConnel; Garcia-Crespo, Andres Jose; Joyce, Kilmer Joseph; Tindell, Allan Randall

    2014-06-03T23:59:59.000Z

    An adaptor assembly for coupling a blade root of a turbine blade to a root slot of a rotor disk is disclosed. The adaptor assembly may generally include an adaptor body having a root configured to be received within the root slot. The adaptor body may also define a slot having an open end configured to receive the blade root. The adaptor body may further define a channel. The adaptor assembly may also include a plate having an outwardly extending foot. The foot may be configured to be received within the channel. Additionally, the plate may be configured to cover at least a portion of the open end of the slot when the foot is received within the channel.

  7. Dual-axis resonance testing of wind turbine blades

    DOE Patents [OSTI]

    Hughes, Scott; Musial, Walter; White, Darris

    2014-01-07T23:59:59.000Z

    An apparatus (100) for fatigue testing test articles (104) including wind turbine blades. The apparatus (100) includes a test stand (110) that rigidly supports an end (106) of the test article (104). An actuator assembly (120) is attached to the test article (104) and is adapted for substantially concurrently imparting first and second forcing functions in first and second directions on the test article (104), with the first and second directions being perpendicular to a longitudinal axis. A controller (130) transmits first and second sets of displacement signals (160, 164) to the actuator assembly (120) at two resonant frequencies of the test system (104). The displacement signals (160, 164) initiate the actuator assembly (120) to impart the forcing loads to concurrently oscillate the test article (104) in the first and second directions. With turbine blades, the blades (104) are resonant tested concurrently for fatigue in the flapwise and edgewise directions.

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

    E-Print Network [OSTI]

    Townsend, Jessica Lee

    2004-01-01T23:59:59.000Z

    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 ...

  9. Investigations of flow and film cooling on turbine blade edge regions

    E-Print Network [OSTI]

    Yang, Huitao

    2006-10-30T23:59:59.000Z

    The inlet temperature of modern gas turbine engines has been increased to achieve higher thermal efficiency and increased output. The blade edge regions, including the blade tip, the leading edge, and the platform, are exposed to the most extreme...

  10. Impact of aerothermal modeling on the estimation of turbine blade life

    E-Print Network [OSTI]

    Collin, Jean E., 1978-

    2004-01-01T23:59:59.000Z

    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 ...

  11. Ris-R-1492(EN) KNOW-BLADE Task-4 report; Navier-

    E-Print Network [OSTI]

    of the aeroelastic stability of wind turbine blades is addressed in this report by advancing the aerodynamic, Navier-Stokes solvers. In this project, structural models for the full wind turbine blade have been

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

    SciTech Connect (OSTI)

    Bir, G.S.; Oyague, F.

    2007-11-01T23:59:59.000Z

    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.

  13. Vibration and crack detection in gas turbine engine compressor blades using Eddy current sensors

    E-Print Network [OSTI]

    Lackner, Matthew, 1980-

    2004-01-01T23:59:59.000Z

    (cont.) in the ECS signal, no definitive method for sensing blade vibration using an ECS has yet been developed.

  14. Methods and apparatus for twist bend coupled (TCB) wind turbine blades

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw; LeMieux, David Lawrence; Pierce, Kirk Gee

    2006-10-10T23:59:59.000Z

    A method for controlling a wind turbine having twist bend coupled rotor blades on a rotor mechanically coupled to a generator includes determining a speed of a rotor blade tip of the wind turbine, measuring a current twist distribution and current blade loading, and adjusting a torque of a generator to change the speed of the rotor blade tip to thereby increase an energy capture power coefficient of the wind turbine.

  15. FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES

    E-Print Network [OSTI]

    FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES.............................................................................................................7 Composite Materials...................................................................................................7 Material Properties

  16. Blades: A New Class of Geometric Primitives for Feeding 3D Parts on Vibratory Tracks

    E-Print Network [OSTI]

    Goldberg, Ken

    of mechanical devices such as wiper blades, grooves and traps. Most of these devices are filters that serve

  17. An investigation of axial-flow compressor blade treatments

    E-Print Network [OSTI]

    Sangerhausen, Charles Roger

    1974-01-01T23:59:59.000Z

    of axial-flow compressor [5] . According to Schlicting [1], the basic methods of controlling the boundary layer on a body are (1) relative motion of the body surface w1th the flow, (2) acceleration of the boundary layer by blowing, (3) suction, (0) in...c methods. The literature survey revealed that three d1fferent techn1ques of boundary layer oontrol have been investigated for applicat1on to axial- flow compressor bladingi these are (1) the slotted blade, (2) the blade shape designed for a...

  18. Providence Heights Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag Jump to:ID8/OrganizationTechProbSolutions JumpInformation forProtiumHeights

  19. Property:Height (m) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid Jump to:DocketFlowGpmGrossGen JumpRating JumpHeight (m)

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

    E-Print Network [OSTI]

    materials structures such as wind turbine blades. Design methodologies to prevent such failures have static and fatigue loading. INTRODUCTION Composite material structures such as wind turbine blades1 PREDICTION OF DELAM INATION IN WIND TURBINE BLADE STRUCTURAL DETAILS John F. Mandell, Douglas S

  1. Ris-R-Report Improved design for large wind turbine blades

    E-Print Network [OSTI]

    for large wind turbine blades of fibre composites (Phase 4) - Summary report Division: 1 Materials Research of wind turbine blade involving geometric and material instabilities 30 5.2 Simulation of crack growthRisø-R-Report Improved design for large wind turbine blades of fibre composites (Phase 4) - Summary

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    LQG control of horizontal wind turbines for blades and tower loads alleviation A. Pintea*, N of power produced by two bladed horizontal variable speed wind turbines. The proposed controller ensures not only an optimal operation of turbines but also enables a compromise with the minimization of the blade

  3. Vibration Analysis of a Vertical Axis Wind Turbine Blade , S.Tullis 2

    E-Print Network [OSTI]

    Tullis, Stephen

    Vibration Analysis of a Vertical Axis Wind Turbine Blade K. Mc Laren 1 , S.Tullis 2 and S.Ziada 3 1 vibration source of a small-scale vertical axis wind turbine currently undergoing field-testing. The turbine at a blade-tip speed ratio (the ratio of the blade rotational velocity to the ambient wind velocity) of 1

  4. LOSS OF ROTOR ISOTROPY AS A BLADE DAMAGE INDICATOR FOR WIND TURBINE STRUCTURE HEALTH MONITORING SYSTEMS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    LOSS OF ROTOR ISOTROPY AS A BLADE DAMAGE INDICATOR FOR WIND TURBINE STRUCTURE HEALTH MONITORING to simulated vibrations of a rotating rotor. KEYWORDS : wind turbine blade, rotor anisotropy, Floquet analysis, OMA INTRODUCTION Blades of modern wind turbines are complex high-tech structures, and their cost

  5. A feasibility study of wind turbine blade surface crack detection using an optical inspection method

    E-Print Network [OSTI]

    McCalley, James D.

    A feasibility study of wind turbine blade surface crack detection using an optical inspection technique was investigated to assess its ability to detect surface flaws on an on-tower wind turbine blade and investors. Rotor blades are one of the largest mechanical components of a wind turbine and cannot

  6. Sparkr Blade Test Centre Wind turbines with a rotor diameter exceed-

    E-Print Network [OSTI]

    Sparkær Blade Test Centre Wind turbines with a rotor diameter exceed- ing 2 metres must have a type of a wind turbine. Failure of a rotor blade in service often involves damage of the entire turbine operating type cer- tification systems for wind turbines. Reg. no. 427 The Sparkær Blade Test Centre became

  7. Numerical Analysis of Winglets on Wind Turbine Blades using CFD Jeppe Johansen

    E-Print Network [OSTI]

    Numerical Analysis of Winglets on Wind Turbine Blades using CFD Jeppe Johansen and Niels N of adding a winglet to a wind turbine rotor is to decrease the total drag from the blades and thereby increase. The resulting pressure difference on an operating wind turbine blade causes inward spanwise flow

  8. QUANTITATIVE DAMAGE ASSESSMENT OF HYBRID COMPOSITE WIND TURBINE BLADES BY ENERGY BASED ACOUSTIC EMISSION SOURCE

    E-Print Network [OSTI]

    Boyer, Edmond

    QUANTITATIVE DAMAGE ASSESSMENT OF HYBRID COMPOSITE WIND TURBINE BLADES BY ENERGY BASED ACOUSTIC in the wind turbine blade. It was tried to apply a new source location method, which has a developed algorithm assessment, source location, wind turbine blade, hybrid composites INTRODUCTION Structural health management

  9. DETECTION OF IMPULSE-LIKE AIRBORNE SOUND FOR DAMAGE IDENTIFICATION IN ROTOR BLADES OF WIND TURBINES

    E-Print Network [OSTI]

    Boyer, Edmond

    DETECTION OF IMPULSE-LIKE AIRBORNE SOUND FOR DAMAGE IDENTIFICATION IN ROTOR BLADES OF WIND TURBINES burdens of wind turbines. To detect damage of rotor blades, several research projects focus on an acoustic, rotor blade, wind turbine INTRODUCTION There are several publications of non destructive damage

  10. Ris-R-1392(EN) Full scale testing of wind turbine blade

    E-Print Network [OSTI]

    Risø-R-1392(EN) Full scale testing of wind turbine blade to failure - flapwise loading Erik R F. Sørensen Risø National Laboratory, Roskilde June 2004 #12;Abstract A 25m wind turbine blade test of a 25m Vestas wind turbine blade. The major results of the entire project can be found

  11. AIAA-98-0057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS

    E-Print Network [OSTI]

    Sweetman, Bert

    AIAA-98-0057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS: PARAMETRIC STUDY WITH MULTIPLE that is most useful in estimating fatigue loads on wind turbine blades. The histograms of rain ow counted measures|can be used to estimate fatigue loads on wind turbine blades. We rst de- scribe a general approach

  12. Effects of Glass Fabric and Laminate Construction on the Fatigue of Resin Infused Blade Materials

    E-Print Network [OSTI]

    Effects of Glass Fabric and Laminate Construction on the Fatigue of Resin Infused Blade Materials. Introduction Wind turbine blades experience very high numbers of fatigue cycles varying between tension and wind conditions. The fatigue of composite laminates appropriate for wind turbine blades has been

  13. PhD position: Numerical study on ice accretion on fan blades and compressor stages

    E-Print Network [OSTI]

    Twente, Universiteit

    PhD position: Numerical study on ice accretion on fan blades and compressor stages Within on fan blades and compressor stages. This research is carried out in the framework of the HAIC (High a computational tool to predict the ice accretion on fan blades and the first compressor stages of commercial jet

  14. Interactive planar multi-blade flows with a global angle of S.P. Kirbya,

    E-Print Network [OSTI]

    Purvis, Richard

    . There are many other applications, for example the flow around wind turbines, in domestic fans, food mixers successive blades and wakes is studied for locally non-symmetric blades aligned with a global angle of attack to the oncoming freestream. The typi- cal blade lies relatively near the centreline of the oncoming wake from

  15. DEVELOPMENT OF AN ULTRASONIC NDT SYSTEM FOR AUTOMATED IN-SITU INSPECTION OF WIND TURBINE BLADES

    E-Print Network [OSTI]

    Boyer, Edmond

    DEVELOPMENT OF AN ULTRASONIC NDT SYSTEM FOR AUTOMATED IN- SITU INSPECTION OF WIND TURBINE BLADES Abington, Cambridge, CB21 6AL, UK bic@brunel.ac.uk ABSTRACT It is crucial to maintain wind turbine blades. This work investigates using pulse-echo ultrasound to detect internal damages in wind turbine blades without

  16. Ducted Turbine Blade Optimization Using Numerical Simulation Michael Shives and Curran Crawford

    E-Print Network [OSTI]

    Pedersen, Tom

    Ducted Turbine Blade Optimization Using Numerical Simulation Michael Shives and Curran Crawford analysis and optimization of ducted turbines. The model is similar to standard blade element momentum. This eliminates many assumptions used in applying the typical blade element momentum (BEM) theory to a turbine

  17. OPERATIONAL MODAL ANALYSIS AND WAVELET TRANSFORMATION FOR DAMAGE IDENTIFICATION IN WIND TURBINE BLADES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    OPERATIONAL MODAL ANALYSIS AND WAVELET TRANSFORMATION FOR DAMAGE IDENTIFICATION IN WIND TURBINE turbine blade. A trail- ing edge debonding was introduced to a SSP 34 m blade mounted on a test rig. Op-frequency modes. KEYWORDS : Wind Turbine Blades, Debonding, Wavelet Transformation, Operational Modal Analysis

  18. On the Flame Height Definition for Upward Flame Spread 

    E-Print Network [OSTI]

    Consalvi, Jean L; Pizzo, Yannick; Porterie, Bernard; Torero, Jose L

    2007-01-01T23:59:59.000Z

    Flame height is defined by the experimentalists as the average position of the luminous flame and, consequently is not directly linked with a quantitative value of a physical parameter. To determine flame heights from ...

  19. Wind Turbine Towers Establish New Height Standards and Reduce...

    Office of Energy Efficiency and Renewable Energy (EERE) 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...

  20. Equivalent roughness height for plane bed under oscillatory flow

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , the bed roughness height of a flat and fixed bed is given in terms of the Nikuradse roughness height (ks may be several orders of magnitude larger than for a fixed bed. This is probably causedEquivalent roughness height for plane bed under oscillatory flow Beno^it Camenen , Magnus Larson

  1. LEVY PROCESS CONDITIONED BY ITS HEIGHT PROCESS January 30, 2012

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    L´EVY PROCESS CONDITIONED BY ITS HEIGHT PROCESS January 30, 2012 MATHIEU RICHARD Abstract. In the present work, we consider spectrally positive L´evy processes (Xt, t 0) not drifting to + and we are interested in conditioning these processes to reach arbitrarily large heights (in the sense of the height

  2. National Wind Tecnology Center Provides Dual Axis Resonant Blade Testing

    SciTech Connect (OSTI)

    Felker, Fort

    2013-11-13T23:59:59.000Z

    NREL's Structural Testing Laboratory at the National Wind Technology Center (NWTC) provides experimental laboratories, computer facilities for analytical work, space for assembling components and turbines for atmospheric testing as well as office space for industry researchers. Fort Felker, center director at the NWTC, discusses NREL's state-of-the-art structural testing capabilities and shows a flapwise and edgewise blade test in progress.

  3. STUDIES OF THE DYNAMICS OF DRY-FRICTION-DAMPED BLADE

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    STUDIES OF THE DYNAMICS OF DRY-FRICTION-DAMPED BLADE ASSEMBLIES by J er^ome Guillen A dissertation . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.3 Multi-DOF systems with a single friction damper . . . . . . . 20 2.3.1 System model with multiple friction dampers . . . . . . 31 2.5 Conclusion

  4. National Wind Tecnology Center Provides Dual Axis Resonant Blade Testing

    ScienceCinema (OSTI)

    Felker, Fort

    2014-06-10T23:59:59.000Z

    NREL's Structural Testing Laboratory at the National Wind Technology Center (NWTC) provides experimental laboratories, computer facilities for analytical work, space for assembling components and turbines for atmospheric testing as well as office space for industry researchers. Fort Felker, center director at the NWTC, discusses NREL's state-of-the-art structural testing capabilities and shows a flapwise and edgewise blade test in progress.

  5. Measurement and analysis of gas turbine blade endwall heat transfer

    E-Print Network [OSTI]

    Lee, Joon Ho

    2001-01-01T23:59:59.000Z

    the aerodynamic flow and external heat transfer distribution around the airfoils and end-wall surfaces. A stationary 5 vane linear cascade is designed and developed to investigate gas turbine blade endwall heat transfer and flow. The test cascade is instrumented...

  6. First Hybrid Turbulence Modeling for Turbine Blade Cooling Sagar Kapadia*

    E-Print Network [OSTI]

    Roy, Subrata

    crossflow. The penetration of cold jet into the main flow creates a complex flowfield. Systematic in the crossflow at an angle =35o . Figure also describes the boundary conditions applied at different faces. Even are the temperatures of crossflow, blade and jet respectively. Sinha et al. 1 carried out experimental work to study

  7. " *.--S, * b different of the turbine's blades in

    E-Print Network [OSTI]

    Ranganathan, Jai

    The Economist #12;" *.--S, * b different of the turbine's blades in unpre&&l$$ ,and confusing ways. The clutter tbi!3-ba,useson the screen is made worse whe+%e signalb bounced around between different turbines-scaleversion atthe siteof a singlewind turbine. It was ableto show a different

  8. Mixing blade system for high-resistance media

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-07-09T23:59:59.000Z

    A blade system is described for stirring and agitating a medium, comprising a shaft bearing a plurality of paddles, each having a different geometry and each having approximately the same rotational moment. The geometrically different paddles sweep through different volumes of the medium to minimize shear zone development and maximize the strength of the system with respect to medium-induced stress. 6 figures.

  9. Maximum likelihood estimation for cooperative sequential adsorption

    E-Print Network [OSTI]

    Burton, Geoffrey R.

    Maximum likelihood estimation for cooperative sequential adsorption Mathew D. Penrose and Vadim;Maximum likelihood estimation for cooperative sequential adsorption M.D. Penrose, Department of the region. Keywords: cooperative sequential adsorption, space-time point pro- cess, maximum likelihood

  10. Estimating a mixed strategy employing maximum entropy

    E-Print Network [OSTI]

    Golan, Amos; Karp, Larry; Perloff, Jeffrey M.

    1996-01-01T23:59:59.000Z

    MIXED STRATEGY EMPLOYING MAXIMUM ENTROPY by Amos Golan LarryMixed Strategy Employing Maximum Entropy Amos Golan Larry S.Abstract Generalized maximum entropy may be used to estimate

  11. Boiler Maximum Achievable Control Technology (MACT) Technical...

    Energy Savers [EERE]

    Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact Sheet, April 2015 Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact...

  12. Optimisation of NSLS-II Blade X-ray Beam Position Monitors: from Photoemission type to Diamond Detector

    SciTech Connect (OSTI)

    ILINSKI P.

    2012-07-10T23:59:59.000Z

    Optimisation of blade type x-ray beam position monitors (XBPM) was performed for NSLS-II undulator IVU20. Blade material, con and #64257;guration and operation principle was analysed in order to improve XBPM performance. Optimisation is based on calculation of the XBPM signal spatial distribution. Along with standard photoemission type XBPM a Diamond Detector Blades (DDB) were analysed as blades for XBPMs. DDB XBPMs can help to overcome drawbacks of the photoemission blade XBPMs.

  13. Fatigue Testing of 9 m Carbon Fiber Wind Turbine Research Blades

    SciTech Connect (OSTI)

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

    2008-01-01T23:59:59.000Z

    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.

  14. The number e^{(1/2)} is the ratio between the time of maximum value and the time of maximum growth rate for restricted growth phenomena?

    E-Print Network [OSTI]

    Zi-Niu Wu

    2013-10-02T23:59:59.000Z

    For many natural process of growth, with the growth rate independent of size due to Gibrat law and with the growth process following a log-normal distribution, the ratio between the time (D) for maximum value and the time (L) for maximum growth rate (inflexion point) is then equal to the square root of the base of the natural logarithm (e^{1/2}). On the logarithm scale this ratio becomes one half ((1/2)). It remains an open question, due to lack of complete data for various cases with restricted growth, whether this e^{1/2} ratio can be stated as e^{1/2}-Law. Two established examples already published, one for an epidemic spreading and one for droplet production, support however this ratio. Another example appears to be the height of humain body. For boys the maximum height occurs near 23 years old while the maximum growth rate is at the age near 14, and there ratio is close to e^{1/2}. The main theoretical base to obtain this conclusion is problem independent, provided the growth process is restricted, such as public intervention to control the spreading of communicable epidemics, so that an entropy is associated with the process and the role of dissipation, representing the mechanism of intervention, is maximized. Under this formulation the principle of maximum rate of entropy production is used to make the production process problem independent.

  15. Coatings for the protection of turbine blades from erosion

    SciTech Connect (OSTI)

    Walsh, P.N.; Quets, J.M.; Tucker, R.C. Jr. [Praxair Surface Technologies, Inc., Indianapolis, IN (United States)

    1995-01-01T23:59:59.000Z

    Many types of turbines, including aircraft gas turbines, steam turbines, and power recovery turbines, suffer from solid particle erosion caused by a variety of materials ingested into the machines. Utilization of various laboratory erosion tests tailored to the specific application by using various erodents, temperatures, velocities, and angles of impact, have been shown to be effective in the development and selection of coatings for the erosion protection of turbine blades and other components. Detonation gun coatings have demonstrated their efficacy in providing substantial protection in many situations. It has now been shown that several tungsten carbide and chromium carbide Super D-Gun{trademark} coatings not only have better erosion resistance than their D-Gun analogs, but cause little or no degradation of the fatigue properties of the blade alloys. Nonetheless, caution should be employed in the application of any laboratory data to a specific situation and additional testing done as warranted by the turbine designer.

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

    SciTech Connect (OSTI)

    Hughes, S.

    2012-05-01T23:59:59.000Z

    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.

  17. Preform spar cap for a wind turbine rotor blade

    DOE Patents [OSTI]

    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

    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.

  18. Heat transfer in a two-pass internally ribbed turbine blade coolant channel with cylindrical vortex generators

    SciTech Connect (OSTI)

    Hibbs, R.; Chen, Y.; Nikitopoulos, D. [Louisiana State Univ., Baton Rouge, LA (United States)] [and others

    1995-10-01T23:59:59.000Z

    The effect of vortex generators on the mass (heat) transfer from the ribbed passage of a two pass turbine blade coolant channel is investigated with the intent of optimizing the vortex generator geometry so that significant enhancements in mass/heat transfer can be achieved. In the experimental configuration considered, ribs are mounted on two opposite walls; all four walls along each pass are active and have mass transfer from their surfaces but the ribs are non-participating. Mass transfer measurements, in the form of Sherwood number ratios, are made along the centerline and in selected inter-rib modules. Results are presented for Reynolds number in the range of 5,000 to 40,000, pitch to rib height ratios of 10.5 and 21, and vortex generator-rib spacing to rib height ratios of 0.55, and 1.5. Centerline and spanwise averaged Sherwood number ratios are presented along with contours of the Sherwood number ratios. Results indicate that the vortex generators induce substantial increases in the local mass transfer rates, particularly along the side walls, and modest increases in the average mass transfer rates. The vortex generators have the effect of making the inter-rib profiles along the ribbed walls more uniform. Along the side walls, horse-shoe vortices that characterize the vortex generator wake are associated with significant mass transfer enhancements. The wake effects and the levels of enhancement decrease somewhat with increasing Reynolds number and decreasing pitch.

  19. Heat transfer in a two-pass internally ribbed turbine blade coolant channel with cylindrical vortex generators

    SciTech Connect (OSTI)

    Hibbs, R.; Acharya, S.; Chen, Y. [Louisiana State Univ., Baton Rouge, LA (United States)] [and others

    1995-12-31T23:59:59.000Z

    The effect of vortex generators on the mass (heat) transfer from the ribbed passage of a two pass turbine blade coolant channel is investigated with the intent of optimizing the vortex generator geometry so that significant enhancements in mass/heat transfer can be achieved. In the experimental configuration considered, ribs are mounted on two opposite walls; all four walls along each pass are active and have mass transfer from their surfaces but the ribs are non-participating. Mass transfer measurements, in the form of Sherwood number ratios, are made along the centerline and in selected inter-rib modules. Results are presented for Reynolds number in the range of 5,000 to 40,000, pitch to rib height ratios of 10.5 and 21, and vortex generator-rib spacing to rib height ratios of 0.55, and 1.5. Centerline and spanwise averaged Sherwood number ratios are presented along with contours of the Sherwood number ratios. Results indicate that the vortex generators induce substantial increases in the local mass transfer rates, particularly along the side walls, and modest increases in the average mass transfer rates. The vortex generators have the effect of making the inter-rib profiles along the ribbed walls more uniform. Along the side walls, horse-shoe vortices that characterize the vortex generator wake are associated with significant mass transfer enhancements. The wake effects and the levels of enhancement decrease somewhat with increasing Reynolds number and decreasing pitch.

  20. Heat transfer in a two-pass internally ribbed turbine blade coolant channel with cylindrical vortex generators

    SciTech Connect (OSTI)

    Hibbs, R.G.; Acharya, S.; Chen, Y.; Nikitopoulos, D.E.; Myrum, T.A. [Louisiana State Univ., Baton Rouge, LA (United States). Mechanical Engineering Dept.

    1998-07-01T23:59:59.000Z

    The effect of vortex generators on the mass (heat) transfer from the ribbed passage of a two-pass turbine blade coolant channel is investigated with the intent of optimizing the vortex generator geometry so that significant enhancements in mass/heat transfer can be achieved. In the experimental configuration considered, ribs are mounted on two opposite walls; all four walls along each pass are active and have mass transfer from their surfaces but the ribs are nonparticipating. Mass transfer measurements, in the form of Sherwood number ratios, are made along the centerline and in selected interrib modules. Results are presented for Reynolds number in the range of 5000 to 40,000 pitch to rib height ratios of 10.5 and 21, and vortex generator-rib spacing to rib height ratios of 0.55 and 1.5. Centerline and spanwise-averaged Sherwood number ratios are presented along with contours of the Sherwood number ratios. Results indicate that the vortex generators lead to substantial increases in the local mass transfer rates, particularly along the side walls, and modest increases in the average mass transfer rates. The vortex generators have the effect of making the interrib profiles along the ribbed walls more uniform. Along the side walls, vortices that characterize the vortex generator wake are associated with significant mass transfer enhancements. The wake effects and the levels of enhancement decrease somewhat with increasing Reynolds number and decreasing pitch.

  1. Energy harvesting to power sensing hardware onboard wind turbine blade

    SciTech Connect (OSTI)

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

    2009-10-05T23:59:59.000Z

    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.

  2. Space variations in axis height of the jet stream core 

    E-Print Network [OSTI]

    Leutwyler, Cooke Hearon

    1965-01-01T23:59:59.000Z

    height, of 55 mb be- tween Model I (troughs) and Model II (ridges). However, the present models of the jet stream do not adequately describe the way a jet stream axis varies in height at a given time. The average presented by Reiter (1958... the Ridge cases, the standard deviation was smaller upstream from the reference height than it was downstream. Therefore the mean curves are more representative and useful as models upstream than they are downstream. C HAP TER I I I HEIGHT VARIATIONS...

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

    SciTech Connect (OSTI)

    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

    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.

  4. Pitch Error and Shear Web Disbond Detection on Wind Turbine Blades...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    American Institute of Aeronautics and Astronautics 1 Pitch Error and Shear Web Disbond Detection on Wind Turbine Blades for Offshore Structural Health and Prognostics Management...

  5. Wind Technology Testing Center Earns A2LA Accreditation for Blade...

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

    by the American Association for Laboratory Accreditation (A2LA) to test wind turbine blades to International Electrotechnical Commission (IEC) standards. The facility is...

  6. SciTech Connect: Development and Validation of a New Blade Element...

    Office of Scientific and Technical Information (OSTI)

    Technologies Office Country of Publication: United States Language: English Subject: 17 WIND ENERGY BLADE ELEMENT MOMENTUM; SKEWED WAKE; FAST; AERODYN; UNSTEADY AERODYNAMICS...

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

    SciTech Connect (OSTI)

    Schreck, S. J.

    2007-01-01T23:59:59.000Z

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

  8. Mixed Mode Static and Fatigue Crack Growth in Wind Blade Paste Adhesives

    E-Print Network [OSTI]

    , static GIc and mixed mode fracture, and fatigue crack growth resistance. I. Introduction Wind turbine blades are large composite structures which are typically resin infusion molded in sections

  9. EFFECTS OF TOUGHENED MATRIX RESINS ON COMPOSITE MATERIALS FOR WIND TURBINE BLADES

    E-Print Network [OSTI]

    EFFECTS OF TOUGHENED MATRIX RESINS ON COMPOSITE MATERIALS FOR WIND TURBINE BLADES by Ricardo Orozco turbine energy project. #12;v TABLE OF CONTENTS LIST OF TABLES

  10. Equivalent Roughness Height for Plane Bed under Steady Flow

    E-Print Network [OSTI]

    US Army Corps of Engineers

    current conditions. In general, owing to dimensional reasons, the bed roughness height of a flat and fixed orders of magnitude larger than for a fixed bed. This is probably caused by the increased energyEquivalent Roughness Height for Plane Bed under Steady Flow Benoît Camenen, Ph.D.1 ; Atilla Bayram

  11. The height and range of watermelons without wall

    E-Print Network [OSTI]

    Thomas Feierl

    2009-04-03T23:59:59.000Z

    We determine the weak limit of the distribution of the random variables "height" and "range" on the set of p-watermelons without wall restriction as the number of steps tends to infinity. Additionally, we provide asymptotics for the moments of the random variable "height".

  12. Computing local p-adic height pairings on hyperelliptic curves

    E-Print Network [OSTI]

    Balakrishnan, Jennifer S

    2010-01-01T23:59:59.000Z

    We describe an algorithm to compute the local component at p of the Coleman-Gross p-adic height pairing on divisors on hyperelliptic curves. As the height pairing is given in terms of a Coleman integral, we also provide new techniques to evaluate Coleman integrals of meromorphic differentials and present our algorithms as implemented in Sage.

  13. Root responses of bermudagrass to mowing height and frequency

    E-Print Network [OSTI]

    Hall, Mark Holman

    1995-01-01T23:59:59.000Z

    of root zone to be studied separately. Common bermudagrass (Cynodon dactylon [L.] Pers.) was used in a mowing height by frequency study, with mowing height treatments of 2.5 and 5.1 cm, and mowing frequencies of 2, 7, and 14 days. Tifgreen bermudagrass (C...

  14. GLOBAL PATTERN OF MESOSCALE VARIABILITY IN SEA SURFACE HEIGHT

    E-Print Network [OSTI]

    Kaplan, Alexey

    GLOBAL PATTERN OF MESOSCALE VARIABILITY IN SEA SURFACE HEIGHT AND ITS DYNAMICAL CAUSES Alexey separate the mesoscale variability of sea surface heights into its spatial and temporal components of mesoscale variability in different areas to dynamical causes. Major portion of it can be explained

  15. LEVY PROCESS CONDITIONED BY ITS HEIGHT PROCESS June 11, 2011

    E-Print Network [OSTI]

    L´EVY PROCESS CONDITIONED BY ITS HEIGHT PROCESS June 11, 2011 MATHIEU RICHARD Abstract. In the present work, we consider spectrally positive L´evy processes (Xt, t 0) not drifting to + and we are interested in conditioning these processes to reach arbitrarily large heights before hitting 0. This way we

  16. Maximum entropy principal for transportation

    SciTech Connect (OSTI)

    Bilich, F. [University of Brasilia (Brazil); Da Silva, R. [National Research Council (Brazil)

    2008-11-06T23:59:59.000Z

    In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.

  17. Blade System Design Study. Part II, final project report (GEC).

    SciTech Connect (OSTI)

    Griffin, Dayton A. (DNV Global Energy Concepts Inc., Seattle, WA)

    2009-05-01T23:59:59.000Z

    As part of the U.S. Department of Energy's Low Wind Speed Turbine program, Global Energy Concepts LLC (GEC)1 has studied alternative composite materials for wind turbine blades in the multi-megawatt size range. This work in one of the Blade System Design Studies (BSDS) funded through Sandia National Laboratories. The BSDS program was conducted in two phases. In the Part I BSDS, GEC assessed candidate innovations in composite materials, manufacturing processes, and structural configurations. GEC also made recommendations for testing composite coupons, details, assemblies, and blade substructures to be carried out in the Part II study (BSDS-II). The BSDS-II contract period began in May 2003, and testing was initiated in June 2004. The current report summarizes the results from the BSDS-II test program. Composite materials evaluated include carbon fiber in both pre-impregnated and vacuum-assisted resin transfer molding (VARTM) forms. Initial thin-coupon static testing included a wide range of parameters, including variation in manufacturer, fiber tow size, fabric architecture, and resin type. A smaller set of these materials and process types was also evaluated in thin-coupon fatigue testing, and in ply-drop and ply-transition panels. The majority of materials used epoxy resin, with vinyl ester (VE) resin also used for selected cases. Late in the project, testing of unidirectional fiberglass was added to provide an updated baseline against which to evaluate the carbon material performance. Numerous unidirectional carbon fabrics were considered for evaluation with VARTM infusion. All but one fabric style considered suffered either from poor infusibility or waviness of fibers combined with poor compaction. The exception was a triaxial carbon-fiberglass fabric produced by SAERTEX. This fabric became the primary choice for infused articles throughout the test program. The generally positive results obtained in this program for the SAERTEX material have led to its being used in innovative prototype blades of 9-m and 30-m length, as well as other non-wind related structures.

  18. Sandia Energy - Wind-Turbine Blade Materials and Reliability Progress

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol Home DistributionTransportation Safety HomeWater PowerEnergyWind-Turbine Blade

  19. Suzhou Red Maple Wind Blade Mould Co | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2,AUDITCalifornia Sector:Shrenik IndustriesState of KuwaitSuper WindSurBlade

  20. 46th Aerospace Sciences Meeting, January 7-10, 2008, Reno, Nevada A Smart Wind Turbine Blade Using Distributed

    E-Print Network [OSTI]

    Nelson, Robert C.

    46th Aerospace Sciences Meeting, January 7-10, 2008, Reno, Nevada A Smart Wind Turbine Blade Using of "smart" wind turbine blades with integrated sensor-actuator-controller modules to im- prove

  1. Height Replacement of Selected Woody Plants Following Burning or Shredding.

    E-Print Network [OSTI]

    Hamilton, W.T.; Kitchen, L.M.; Scifres, C.J.

    1981-01-01T23:59:59.000Z

    periods. %e e ' riment was designed as a rm=trd cmnplete+bloCL deskgn with t a o repticatbms. T h g S i g h empioped 9 h e - 'hie -wewin bo:*iriny of the l&a ' dfded o P - the plots (Scifps 1ss81. i?w ~rmeYIt l~p-m~tr lLed ltjeIt'trcwMs, 3.T by...- tions accounted for 87 pecmt of the variation in height change of blackbrush acacia. Burning did -@t affect height increase based on comparison with unburned blackbrush acacia. Blackbrush acacia height replacement was slower than that of honey mes...

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

    SciTech Connect (OSTI)

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

    2010-12-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Hughes, S.

    2012-05-01T23:59:59.000Z

    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.

  4. EMBEDDED BLADE MICROSYSTEM AND EVENTS RECORDER FOR DRONE STRUCTURAL HEALTH MONITORING

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    EMBEDDED BLADE MICROSYSTEM AND EVENTS RECORDER FOR DRONE STRUCTURAL HEALTH MONITORING M. Lastapis1@laas.fr ABSTRACT Structural health monitoring is today growing challenge. A good health structure allows to assure, Blade, Embedded, Microsystem. 1) INTRODUCTION Structural health monitoring (SHM) is a recent domain

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

    E-Print Network [OSTI]

    uni-directional wind turbine fiber-reinforced composite material with an epoxy resin were utilized of wind turbine blades have essentially dictated the use of low cost fiberglass composite materials. Even1 Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects Jared W. Nelson

  6. Modelling and Analysis of Multi-Stage Systems of Mistuned Bladed Disks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    uncertainty may be due to numerous factors such as material inho- mogeneity, manufacturing processes of uncertainties in complex computational models. In turbine engines rotating components (bladed disks), one of mistuning phenomena in multi- stage systems of bladed disks. Indeed, in modern turbine engines, which

  7. Design optimization of a 2D blade by means of milling Christian Vessaza

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of turbine blades in order to ensure that the simulated machined surface produces the expected hydraulic, Laboratory for Hydraulic Machines, avenue de Cour 33 bis, 1007 Lausanne, Switzerland bLURPA, ENS Cachan, Switzerland Abstract In a conventional design and manufacturing process, turbine blades are modeled based

  8. Ris-R-1374(EN) Design of a 21 m Blade with Ris-A1

    E-Print Network [OSTI]

    , power curve and fatigue loads were derived on basis of the measurements. Most of the design criteria as the wind turbine with LM 21.0P blades but at the same time a 15% decrease in blade fatigue loads. However National Laboratory, made the power curve analysis. · Peter Fuglsang, Risø National Laboratory, responsible

  9. High Fidelity Modeling of Blade Row Interaction in a Transonic Compressor

    E-Print Network [OSTI]

    Cincinnati, University of

    High Fidelity Modeling of Blade Row Interaction in a Transonic Compressor Michael G. List in a transonic compressor, a time-accurate simulation of a transonic compressor rig was developed. Initially on the compressor. Three dierent axial spacings between the rotor and the upstream blade row have been simulated

  10. HIGH REYNOLDS NUMBER FLOW PAST MANY BLADES IN EXTREME GROUND EFFECT

    E-Print Network [OSTI]

    Purvis, Richard

    blades have much practical importance, such as helicopter aerodynamics, in fans, propellers, wind turbines, food mixers, hover mowers and so on (1­4). Many body interactions are also important effects, upstream influence and blade-wake interactions make the flow structures highly non

  11. Resonances of a Forced Mathieu Equation with Reference to Wind Turbine Blades

    E-Print Network [OSTI]

    Feeny, Brian

    Resonances of a Forced Mathieu Equation with Reference to Wind Turbine Blades Venkatanarayanan , a blade takes on cyclic transverse loading due to both gravity and aerodynamic forces with effects of wind Engineering Michigan State University East Lansing, Michigan 48824 Abstract A horizontal axis wind turbine

  12. How kelp produce blade shapes suited to different flow regimes: A new wrinkle

    E-Print Network [OSTI]

    Mahadevan, L.

    How kelp produce blade shapes suited to different flow regimes: A new wrinkle M. A. R. Koehl,1,Ã? W bull kelp, Nereocystis luetkeana, to investigate how these ecomorphological differences are produced, strap-like blades of kelp from habitats with rapid flow collapse into streamlined bundles and flutter

  13. Ris-R-Report Improved design for large wind turbine blades

    E-Print Network [OSTI]

    Risø-R-Report Improved design for large wind turbine blades of fibre composites (Phase 3) - Summary: Improved design for large wind turbine blades of fibre composites (Phase 3) - Summary report Division: 1 char.): An overview is given of the activities of the project "Improved design for large wind turbine

  14. Isogeometric Simulation of Turbine Blades for Aircraft Engines David Gromann1

    E-Print Network [OSTI]

    Jüttler, Bert

    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

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

    E-Print Network [OSTI]

    Tullis, Stephen

    Blade Offset and Pitch Effects on a High Solidity Vertical Axis Wind Turbine Andrzej J. Fiedler ABSTRACT A high solidity, small scale, 2.5m diameter by 3m high Vertical Axis Wind Turbine (VAWT in an open-air wind tunnel facility to investigate the effects of preset toe-in and toe-out turbine blade

  16. A Critical Assessment of Computer Tools for Calculating Composite Wind Turbine Blade Properties

    E-Print Network [OSTI]

    Yu, Wenbin

    A Critical Assessment of Computer Tools for Calculating Composite Wind Turbine Blade Properties Hui assess several computer tools for calculating the inertial and structural properties of wind turbine, and a realistic composite wind turbine blade are used to evaluate the performance of different tools

  17. CFD Simulation of Dynamic Thrust and Radial Forces on a Vertical Axis Wind Turbine Blade

    E-Print Network [OSTI]

    Tullis, Stephen

    CFD Simulation of Dynamic Thrust and Radial Forces on a Vertical Axis Wind Turbine Blade K. Mc vibration source of a small scale vertical axis wind turbine. The dynamic loading on the blades of the turbine, as they rotate about the central shaft and travel through a range of relative angles of attack

  18. Swept Blade Aero-Elastic Model for a Small Wind Turbine (Presentation)

    SciTech Connect (OSTI)

    Damiani, R.; Lee, S.; Larwood, S.

    2014-07-01T23:59:59.000Z

    A preprocessor for analyzing preswept wind turbines using the in-house aero-elastic tool coupled with a multibody dynamic simulator was developed. A baseline 10-kW small wind turbine with straight blades and various configurations that featured bend-torsion coupling via blade-tip sweep were investigated to study their impact on ultimate loads and fatigue damage equivalent loads.

  19. How hard can it be to pitch a wind turbine blade? Moment of inertia approximately

    E-Print Network [OSTI]

    How hard can it be to pitch a wind turbine blade? Moment of inertia approximately as a small car (1 ton) on 7 m arm Morten Hartvig Hansen Wind Energy Department Risø, DTU #12;How hard can it be to pitch a wind turbine blade? Hydraulic pitch actuator for the virtual NREL 5 MW turbine · Motivation · Actuator

  20. Proof-of-Concept Manufacturing and Testing of Composite Wind Generator Blades Made by HCBMP (High Compression Bladder Molded Prepreg)

    SciTech Connect (OSTI)

    William C. Leighty; DOE Project Officer - Keith Bennett

    2005-10-04T23:59:59.000Z

    Proof-of-Concept Manufacturing and Testing of Composite Wind Generator Blades Made by HCBMP (High Compression Bladder Molded Prepreg)

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

    SciTech Connect (OSTI)

    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

    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.

  2. User's Guide to PreComp (Pre-Processor for Computing Composite Blade Properties)

    SciTech Connect (OSTI)

    Bir, G. S.

    2006-01-01T23:59:59.000Z

    PreComp (Pre-processor for computing Composite blade structural properties) was developed to compute the stiffness and inertial properties of a composite blade. The code may also be used to compute the structural properties of a metallic blade by treating it as a special case of an isotropic composite material. This guide provides step-by-step instructions on how to prepare input files (specify blade external geometry and internal structural layup of composite laminates), how to execute the code, and how to interpret the output properties. PreComp performs extensive checks for completeness, range, and viability of input data; these are also discussed in this manual. The code runs fast, usually in a fraction of a second, and requires only a modest knowledge of the composites and laminates schedule typically used in blades.

  3. The Forming of AISI 409 sheets for fan blade manufacturing

    SciTech Connect (OSTI)

    Foroni, F. D.; Menezes, M. A.; Moreira Filho, L. A. [ITA - Aeronautic Technological Institute, IEM, Praca Mal. Eduardo Gomes, 50 - Vila das Acacias - S. J. Campos, Brasil - CEP 1228-900 (Brazil)

    2007-04-07T23:59:59.000Z

    The necessity of adapting the standardized fan models to conditions of higher temperature has emerged due to the growth of concern referring to the consequences of the gas expelling after the Mont Blanc tunnel accident in Italy and France, where even though, with 100 fans in operation, 41 people died. The objective of this work is to present an alternative to the market standard fans considering a new technology in constructing blades. This new technology introduces the use of the stainless steel AISI 409 due to its good to temperatures of gas exhaust from tunnels in fire situation. The innovation is centered in the process of a deep drawing of metallic sheets in order to keep the ideal aerodynamic superficies for the fan ideal performance. Through the impression of circles on the sheet plane it is shown, experimentally, that, during the pressing process, the more deformed regions on the sheet plane of the blade can not reach the deformation limits of the utilized sheet material.

  4. Heat transfer in leading and trailing edge cooling channels of the gas turbine blade under high rotation numbers

    E-Print Network [OSTI]

    Liu, Yao-Hsien

    2009-05-15T23:59:59.000Z

    The gas turbine blade/vane internal cooling is achieved by circulating the compressed air through the cooling passages inside the turbine blade. Leading edge and trailing edge of the turbine blade are two critical regions which need to be properly...

  5. Introduction Due to the demand for efficiency in turbomachinery, the clearance between the casing and the blades

    E-Print Network [OSTI]

    Barthelat, Francois

    Introduction Due to the demand for efficiency in turbomachinery, the clearance between the casing plastic ma- terial to prevent direct contact between the blade and the casing. However, blade to simulate the wear of abradable coating material on the casing due to blade/abradable con- tacts, a plastic

  6. 7,511,624 Wind Energy Overview: Device for monitoring the balance and integrity of wind turbine blades either in

    E-Print Network [OSTI]

    Maxwell, Bruce D.

    turbine blades either in service or as a quality control step in the manufacturing process Researchers oscillations (including imbalances and tracking variations) in wind turbine blades. This technology was tested covering the RPM rate of any wind turbine blade. This invention directly targets the operational monitoring

  7. 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

  8. Wind Turbine Inspection Technology Reaches New Heights | GE Global...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Wind Turbine Inspection Technology Reaches New Heights Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new...

  9. age body height: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the pth power of height h with 73 <83. Further arguments based on stability and heat loss suggest that p should be close to 83. The arguments are extended to suggest...

  10. Microprocessor-based ultrasonic height controller for sugarcane harvesters

    E-Print Network [OSTI]

    Coad, Craig Allan

    1980-01-01T23:59:59.000Z

    MICROPROCESSOR-BASED ULTRASONIC HEIGHT CONTROLLER FOR SUGARCANE HARVESTERS A Thesis by CRAIG ALLAN GOAD Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... May 1980 Major Subject: Electrical Engineering MICROPROCESSOR-BASED ULTRASONIC HEIGHT CONTROLLER FOR SUGARCANE HARVESTERS A Thesis by CRAIG ALLAN GOAD Approved as to style and content by: V. T. Rhyne (Chairman of Committee) Charlie G. Coble...

  11. Control of bed height in a fluidized bed gasification system

    DOE Patents [OSTI]

    Mehta, Gautam I. (Greensburg, PA); Rogers, Lynn M. (Export, PA)

    1983-12-20T23:59:59.000Z

    In a fluidized bed apparatus a method for controlling the height of the fdized bed, taking into account variations in the density of the bed. The method comprises taking simultaneous differential pressure measurements at different vertical elevations within the vessel, averaging the differential pressures, determining an average fluidized bed density, then periodically calculating a weighting factor. The weighting factor is used in the determination of the actual bed height which is used in controlling the fluidizing means.

  12. Incorporating Rigorous Height Determination into Unified Fracture Design

    E-Print Network [OSTI]

    Pitakbunkate, Termpan

    2010-10-12T23:59:59.000Z

    to find the maximum productivity index for a given proppant amount. Then, the dimensionless fracture conductivity index corresponding to the maximum productivity index can be computed. The penetration ration, the fracture length, and the propped fracture...

  13. Optimization Online - Efficient Heuristic Algorithms for Maximum ...

    E-Print Network [OSTI]

    T. G. J. Myklebust

    2012-11-19T23:59:59.000Z

    Nov 19, 2012 ... Efficient Heuristic Algorithms for Maximum Utility Product Pricing Problems. T. G. J. Myklebust(tmyklebu ***at*** csclub.uwaterloo.ca)

  14. Hot spot detection system for vanes or blades of a combustion turbine

    DOE Patents [OSTI]

    Twerdochlib, M.

    1999-02-02T23:59:59.000Z

    This invention includes a detection system that can determine if a turbine component, such as a turbine vane or blade, has exceeded a critical temperature, such as a melting point, along any point along the entire surface of the vane or blade. This system can be employed in a conventional combustion turbine having a compressor, a combustor and a turbine section. Included within this system is a chemical coating disposed along the entire interior surface of a vane or blade and a closed loop cooling system that circulates a coolant through the interior of the vane or blade. If the temperature of the vane or blade exceeds a critical temperature, the chemical coating will be expelled from the vane or blade into the coolant. Since while traversing the closed loop cooling system the coolant passes through a detector, the presence of the chemical coating in the coolant will be sensed by the system. If the chemical coating is detected, this indicates that the vane or blade has exceeded a critical temperature. 5 figs.

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

    SciTech Connect (OSTI)

    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

    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.

  16. Hot spot detection system for vanes or blades of a combustion turbine

    DOE Patents [OSTI]

    Twerdochlib, Michael (Oviedo, FL)

    1999-01-01T23:59:59.000Z

    This invention includes a detection system that can determine if a turbine component, such as a turbine vane or blade, has exceeded a critical temperature, such as a melting point, along any point along the entire surface of the vane or blade. This system can be employed in a conventional combustion turbine having a compressor, a combustor and a turbine section. Included within this system is a chemical coating disposed along the entire interior surface of a vane or blade and a closed loop cooling system that circulates a coolant through the interior of the vane or blade. If the temperature of the vane or blade exceeds a critical temperature, the chemical coating will be expelled from the vane or blade into the coolant. Since while traversing the closed loop cooling system the coolant passes through a detector, the presence of the chemical coating in the coolant will be sensed by the system. If the chemical coating is detected, this indicates that the vane or blade has exceeded a critical temperature.

  17. Composite turbine blade design options for Claude (open) cycle OTEC power systems

    SciTech Connect (OSTI)

    Penney, T.R.

    1985-11-01T23:59:59.000Z

    Small-scale turbine rotors made from composites offer several technical advantages for a Claude (open) cycle ocean thermal energy conversion (OTEC) power system. Westinghouse Electric Corporation has designed a composite turbine rotor/disk using state-of-the-art analysis methods for large-scale (100-MW/sub e/) open cycle OTEC applications. Near-term demonstrations using conventional low-pressure turbine blade shapes with composite material would achieve feasibility and modern credibility of the open cycle OTEC power system. Application of composite blades for low-pressure turbo-machinery potentially improves the reliability of conventional metal blades affected by stress corrosion.

  18. An automatic cutting height control system for a sugarcane harvester

    E-Print Network [OSTI]

    Hale, Scott Andrew

    1985-01-01T23:59:59.000Z

    ). . . . . 53 22. 23. Effect of the soil-stalk weight factor on the ground average, and the stalk average A comparison of Avg and Avs calculated from laboratory data with both real numbers, and integer numbers. . . . . . . 57 24 . A graph of a portion... factor, W. By calculating the difference between Avg and Avs, as equation (5) shows, the height of the sugarcane stubble remaining after cutting, 0, was to be determined. D = Avg - Avs (5) where: D - the height of the sugarcane stubble remaining...

  19. An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem

    E-Print Network [OSTI]

    Parthasarathy, Nikhil Kaushik

    2004-09-30T23:59:59.000Z

    In this thesis, a novel approach is presented for blade loss simulation of an aircraft gas turbine rotor mounted on rolling element bearings with squeeze film dampers, seal rub and enclosed in a flexible housing. The modal truncation augmentation...

  20. Blade tip clearance effect on the performance and flow field of a three stage axial turbine

    E-Print Network [OSTI]

    Abdel-Fattah, Sharef Aly

    2003-01-01T23:59:59.000Z

    The effect of a 1.5 % blade tip clearance on a rotating three stage turbine under different operating points was investigated using radially and circumferentially traversed five hole pressure probes. The probes were used to obtain flow field total...

  1. A microwear study of Clovis blades from the Gault site, Bell County, Texas

    E-Print Network [OSTI]

    Minchak, Scott Alan

    2009-06-02T23:59:59.000Z

    Prehistoric quarries in America are poorly understood and thus problematical to take into account when making inferences about past behavior. A microwear analysis of Clovis blades from the 2000 Texas A&M University excavations at the Gault site (41...

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

    SciTech Connect (OSTI)

    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

    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.

  3. TEMPERATURE AND MOISTURE EFFECTS ON COMPOSITE MATERIALS FOR WIND TURBINE BLADES

    E-Print Network [OSTI]

    TEMPERATURE AND MOISTURE EFFECTS ON COMPOSITE MATERIALS FOR WIND TURBINE BLADES by Mei Li A thesis graduate students in the composite materials group for their help and kindness. Finally, thanks to my dear

  4. FRACTURE OF SKIN-STIFFENER INTERSECTIONS IN COMPOSITE WIND TURBINE BLADE STRUCTURES

    E-Print Network [OSTI]

    FRACTURE OF SKIN-STIFFENER INTERSECTIONS IN COMPOSITE WIND TURBINE BLADE STRUCTURES by Darrin John to the other graduate students in the composite materials group for your smiles and friendships over the past Material .........................................................................................10

  5. Improving the manufacturing yield of investment cast turbine blades through robust design

    E-Print Network [OSTI]

    Margetts, David (David Lawrence)

    2008-01-01T23:59:59.000Z

    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 ...

  6. BeamDyn: A High-Fidelity Wind Turbine Blade Solver in the FAST...

    Office of Scientific and Technical Information (OSTI)

    BeamDyn: A High-Fidelity Wind Turbine Blade Solver in the FAST Modular Framework: Preprint Re-direct Destination: BeamDyn, a Legendre-spectral-finite-element implementation of...

  7. A Model of Compressor Blade Row Interaction with Shock Induced Vortex Shedding

    E-Print Network [OSTI]

    Cincinnati, University of

    A Model of Compressor Blade Row Interaction with Shock Induced Vortex Shedding Mark G. Turner = circulation = trailing edge thickness = shock angle = density I. Introduction ransonic compressor stages AIAA. Research Scientist, Compressor Aerodynamic Research Laboratory, Associate Fellow AIAA

  8. Numerical Investigation of Temperature Distribution on a High Pressure Gas Turbine Blade

    E-Print Network [OSTI]

    Zirakzadeh, Hootan

    2014-08-10T23:59:59.000Z

    ’t necessarily provide the most accurate results that could be obtained by performing an experiment or precise CFD simulations. Different systems of blade external and internal cooling, such as rib turbulated cooling, impingement cooling, pin-fins, and injection...

  9. Quarter Annulus Simulations of Blade Row Interaction at Several Gaps and Discussion of

    E-Print Network [OSTI]

    Cincinnati, University of

    annulus simulations to investigate the physics involved in the rotor bow shock interaction with a highly loaded upstream blade row and its eect on the compressor. Three dierent axial spacings between the rotor

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

    E-Print Network [OSTI]

    Chen, Chang

    2013-05-08T23:59:59.000Z

    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...

  11. Implementation of a Biaxial Resonant Fatigue Test Method on a Large Wind Turbine Blade

    SciTech Connect (OSTI)

    Snowberg, D.; Dana, S.; Hughes, S.; Berling, P.

    2014-09-01T23:59:59.000Z

    A biaxial resonant test method was utilized to simultaneously fatigue test a wind turbine blade in the flap and edge (lead-lag) direction. Biaxial resonant blade fatigue testing is an accelerated life test method utilizing oscillating masses on the blade; each mass is independently oscillated at the respective flap and edge blade resonant frequency. The flap and edge resonant frequency were not controlled, nor were they constant for this demonstrated test method. This biaxial resonant test method presented surmountable challenges in test setup simulation, control and data processing. Biaxial resonant testing has the potential to complete test projects faster than single-axis testing. The load modulation during a biaxial resonant test may necessitate periodic load application above targets or higher applied test cycles.

  12. FATIGUE OF SKIN-STIFFENER INTERSECTIONS IN COMPOSITE WIND TURBINE BLADE STRUCTURES

    E-Print Network [OSTI]

    FATIGUE OF SKIN-STIFFENER INTERSECTIONS IN COMPOSITE WIND TURBINE BLADE STRUCTURES by Robert B in the Instron and Composite Laboratories toward the end of the experimental research. Finally, special thanks

  13. Image Analysis of Turbine Blades Using CT Scans| GE Global Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    are hidden and undetected. These flaws can occur during the manufacturing processes of turbine blades in a jet or gas engine. If large enough, they can have significant impact on...

  14. Blade tonal noise reduction using tail articulation at high Reynolds number

    E-Print Network [OSTI]

    Macumber, Daniel Lee, 1981-

    2005-01-01T23:59:59.000Z

    The biologically inspired method of tail articulation is investigated as a means of reducing tonal noise due to the stator wake blade interaction in underwater vehicles. This work is experimental in nature and conducted ...

  15. Maximum entropy segmentation of broadcast news 

    E-Print Network [OSTI]

    Christensen, Heidi; Kolluru, BalaKrishna; Gotoh, Yoshihiko; Renals, Steve

    2005-01-01T23:59:59.000Z

    speech recognizer and subsequently segmenting the text into utterances and topics. A maximum entropy approach is used to build statistical models for both utterance and topic segmentation. The experimental work addresses the effect on performance...

  16. The prediction of airloads on a cascade of staggered blades in oscillatory compressible subsonic flow

    E-Print Network [OSTI]

    Sovinski, John Robert

    1975-01-01T23:59:59.000Z

    THE PREDICTION OF AIRLOADS ON A CASCADE OF STAGGERED BLADES IN OSCILLATORY COMPRESSIBLE SUBSONIC FLOW A Thesis by JOHN ROBERT SOVINSKI Submitted to the Graduate College of Texas ARM University in partial fulfillment of. the requirement... for the degree of MASTER OF SCIENCE May 1975 Major Subject: Aerospace Engineering THE PREDICTION OF AIRLOADS ON A CASCADE OF STAGGERED BLADES IN OSCILLATORY COMPRESSIBLE SUBSONIC FLOW A Thesis by JOHN ROBERT SOVINSKI Approved as to style and content by...

  17. Method and apparatus for reducing rotor blade deflections, loads, and/or peak rotational speed

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw; Pierce, Kirk Gee

    2006-10-17T23:59:59.000Z

    A method for reducing at least one of loads, deflections of rotor blades, or peak rotational speed of a wind turbine includes storing recent historical pitch related data, wind related data, or both. The stored recent historical data is analyzed to determine at least one of whether rapid pitching is occurring or whether wind speed decreases are occurring. A minimum pitch, a pitch rate limit, or both are imposed on pitch angle controls of the rotor blades conditioned upon results of the analysis.

  18. Structural Design of a Horizontal-Axis Tidal Current Turbine Composite Blade

    SciTech Connect (OSTI)

    Bir, G. S.; Lawson, M. J.; Li, Y.

    2011-10-01T23:59:59.000Z

    This paper describes the structural design of a tidal composite blade. The structural design is preceded by two steps: hydrodynamic design and determination of extreme loads. The hydrodynamic design provides the chord and twist distributions along the blade length that result in optimal performance of the tidal turbine over its lifetime. The extreme loads, i.e. the extreme flap and edgewise loads that the blade would likely encounter over its lifetime, are associated with extreme tidal flow conditions and are obtained using a computational fluid dynamics (CFD) software. Given the blade external shape and the extreme loads, we use a laminate-theory-based structural design to determine the optimal layout of composite laminas such that the ultimate-strength and buckling-resistance criteria are satisfied at all points in the blade. The structural design approach allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. In addition, certain fabrication criteria are imposed, for example, each composite laminate must be an integral multiple of its constituent ply thickness. In the present effort, the structural design uses only static extreme loads; dynamic-loads-based fatigue design will be addressed in the future. Following the blade design, we compute the distributed structural properties, i.e. flap stiffness, edgewise stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Such properties are required by hydro-elastic codes to model the tidal current turbine and to perform modal, stability, loads, and response analyses.

  19. Polymer solar cell by blade coating Yu-Han Chang a

    E-Print Network [OSTI]

    as that of inorganic solar cells, the potential of low-cost and roll- to-roll process on flexible substrates makesPolymer solar cell by blade coating Yu-Han Chang a , Shin-Rong Tseng a , Chun-Yu Chen a , Hsin cell Bulk hetero-junction Blade coating a b s t r a c t Polymer bulk hetero-junction solar cells

  20. Morphology Height, RCD, usability --<1 Root:shoot ratio --4

    E-Print Network [OSTI]

    , seeking to detect cold storage and other forms of damage to plants, to a set of techniques to assess to the planting site from cold storage on four separate occasions during the planting season. Plants with REL: · assessing height and root collar diameter (RCD) (compared with an industry standard BS 3936 part 4 (BSI

  1. Hierarchical occlusion culling for arbitrarily-meshed height fields 

    E-Print Network [OSTI]

    Edmondson, Paul Michael

    2004-09-30T23:59:59.000Z

    Many graphics applications today have need for high-speed 3-D visualization of height fields. Most of these applications deal with the display of digital terrain models characterized by a simple, but vast, non-overlapping mesh of triangles. A great...

  2. Height variation of the vector magnetic field in solar spicules

    E-Print Network [OSTI]

    Suarez, D Orozco; Bueno, J Trujillo

    2015-01-01T23:59:59.000Z

    Proving the magnetic configuration of solar spicules has hitherto been difficult due to the lack of spatial resolution and image stability during off-limb ground-based observations. We report spectropolarimetric observations of spicules taken in the He I 1083 nm spectral region with the Tenerife Infrared Polarimeter II at the German Vacuum Tower Telescope of the Observatorio del Teide (Tenerife; Canary Islands; Spain). The data provide the variation with geometrical height of the Stokes I, Q, U, and V profiles whose encoded information allows the determination of the magnetic field vector by means of the HAZEL inversion code. The inferred results show that the average magnetic field strength at the base of solar spicules is about 80 gauss and then it decreases rapidly with height to about 30 gauss at a height of 3000 km above the visible solar surface. Moreover, the magnetic field vector is close to vertical at the base of the chromosphere and has mid inclinations (about 50 degree) above 2 Mm height.

  3. Offshore Series Wind Turbine Variable Hub heights & rotor diameters

    E-Print Network [OSTI]

    Firestone, Jeremy

    3.6MW Offshore Series Wind Turbine GE Energy #12;Feature Variable Hub heights & rotor diameters-savings feature, considering the rigors of offshore power generation. The 3.6 MW offshore wind turbine also, for both on and offshore use. Special features include... As the world's first commercially available wind

  4. TECHNICAL PAPER Time dependent simulation of active flying height control

    E-Print Network [OSTI]

    Fainman, Yeshaiahu

    of the heater were estimated by measuring the transient response of the TFC slider to a step function. Figure 2 (TFC) slider as a function of the power input to the heater element. The Reynolds equation is used and flying height of the slider. The power input signal to the heater element is optimized using convex

  5. Aerodynamic pressure and flow-visualization measurement from a rotating wind turbine blade

    SciTech Connect (OSTI)

    Butterfield, C.P.

    1988-11-01T23:59:59.000Z

    Aerodynamic, load, flow-visualization, and inflow measurements have been made on a 10-m, three-bladed, downwind, horizontal-axis wind turbine (HAWT). A video camera mounted on the rotor was used to record nighttime and daytime video images of tufts attached to the low-pressure side of a constant-chord, zero-twist blade. Load measurements were made using strain gages mounted at every 10% of the blade's span. Pressure measurements were made at 80% of the blade's span. Pressure taps were located at 32 chordwise positions, revealing pressure distributions comparable with wind tunnel data. Inflow was measured using a vertical-plane array of eight propvane and five triaxial (U-V-W) prop-type anemometers located 10 m upwind in the predominant wind direction. One objective of this comprehensive research program was to study the effects of blade rotation on aerodynamic behavior below, near, and beyond stall. To this end, flow patterns are presented here that reveal the dynamic and steady behavior of flow conditions on the blade. Pressure distributions are compared to flow patterns and two-dimensional wind tunnel data. Separation boundary locations are shown that change as a function of spanwise location, pitch angle, and wind speed. 6 refs., 23 figs., 1 tab.

  6. Evaluation of Blade-Strike Models for Estimating the Biological Performance of Kaplan Turbines

    SciTech Connect (OSTI)

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

    2007-11-10T23:59:59.000Z

    Bio-indexing of hydroturbines is an important means to optimize passage conditions for fish by identifying operations for existing and new design turbines that minimize the probability of injury. Cost-effective implementation of bio-indexing requires the use of tools such as numerical and physical turbine models to generate hypotheses for turbine operations that can be tested at prototype scales using live fish. Numerical deterministic and stochastic blade strike models were developed for a 1:25-scale physical turbine model built by the U.S. Army Corps of Engineers for the original design turbine at McNary Dam and for prototype-scale original design and replacement minimum gap runner (MGR) turbines at Bonneville Dam's first powerhouse. Blade strike probabilities predicted by both models were comparable with the overall trends in blade strike probability observed in both prototype-scale live fish survival studies and physical turbine model using neutrally buoyant beads. The predictions from the stochastic model were closer to the experimental data than the predictions from the deterministic model because the stochastic model included more realistic consideration of the aspect of fish approaching to the leading edges of turbine runner blades. Therefore, the stochastic model should be the preferred method for the prediction of blade strike and injury probability for juvenile salmon and steelhead using numerical blade-strike models.

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

    SciTech Connect (OSTI)

    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

    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.

  8. Calculation of CO2 column heights in depleted gas fields from known pre-production gas column heights

    E-Print Network [OSTI]

    Calculation of CO2 column heights in depleted gas fields from known pre-production gas column that the CO2 is in a dense phase (either liquid or supercritical). Accurate assessment of the storage capacity also requires an estimation of the amount of CO2 that can be safely stored beneath the reservoir seal

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

    SciTech Connect (OSTI)

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

    2006-05-01T23:59:59.000Z

    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.

  10. Blade Testing Equipment Development and Commercialization: Cooperative Research and Development Final Report, CRADA Number CRD-09-346

    SciTech Connect (OSTI)

    Snowberg, D.; Hughes, S.

    2013-04-01T23:59:59.000Z

    Blade testing is required to meet wind turbine design standards, reduce machine cost, and reduce the technical and financial risk of deploying mass-produced wind turbine models. NREL?s National Wind Technology Center (NWTC) in Colorado is the only blade test facility in the U.S. capable of performing full-scale static and fatigue testing of multi-megawatt-scale wind turbine blades. Rapid growth in wind turbine size over the past two decades has outstripped the size capacity of the NWTC blade test facility leaving the U.S. wind industry without a suitable means of testing blades for large land-based and offshore turbines. This CRADA will develop and commercialize testing technologies and test equipment, including scaling up, value engineering, and testing of equipment to be used at blade testing facilities in the U.S. and around the world.

  11. Cell development obeys maximum Fisher information

    E-Print Network [OSTI]

    B. R. Frieden; R. A. Gatenby

    2014-04-29T23:59:59.000Z

    Eukaryotic cell development has been optimized by natural selection to obey maximal intracellular flux of messenger proteins. This, in turn, implies maximum Fisher information on angular position about a target nuclear pore complex (NPR). The cell is simply modeled as spherical, with cell membrane (CM) diameter 10 micron and concentric nuclear membrane (NM) diameter 6 micron. The NM contains about 3000 nuclear pore complexes (NPCs). Development requires messenger ligands to travel from the CM-NPC-DNA target binding sites. Ligands acquire negative charge by phosphorylation, passing through the cytoplasm over Newtonian trajectories toward positively charged NPCs (utilizing positive nuclear localization sequences). The CM-NPC channel obeys maximized mean protein flux F and Fisher information I at the NPC, with first-order delta I = 0 and approximate 2nd-order delta I = 0 stability to environmental perturbations. Many of its predictions are confirmed, including the dominance of protein pathways of from 1-4 proteins, a 4nm size for the EGFR protein and the approximate flux value F =10^16 proteins/m2-s. After entering the nucleus, each protein ultimately delivers its ligand information to a DNA target site with maximum probability, i.e. maximum Kullback-Liebler entropy HKL. In a smoothness limit HKL approaches IDNA/2, so that the total CM-NPC-DNA channel obeys maximum Fisher I. Thus maximum information approaches non-equilibrium, one condition for life.

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

    SciTech Connect (OSTI)

    Galib Abumeri; Frank Abdi (PhD)

    2012-02-16T23:59:59.000Z

    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

  13. New methodology to determine the terminal height of a fireball

    E-Print Network [OSTI]

    Moreno-Ibáñez, Manuel; Trigo-Rodríguez, Josep M

    2015-01-01T23:59:59.000Z

    Despite ablation and drag processes associated with atmospheric entry of meteoroids were a subject of intensive study over the last century, little attention was devoted to interpret the observed fireball terminal height. This is a key parameter because it not only depends on the initial mass, but also on the bulk physical properties of the meteoroids and hence of their ability to ablate in the atmosphere. In this work we have developed a new approach that is tested using the fireball terminal heights observed by the Meteorite Observation and Recovery Project operated in Canada between 1970-1985 (hereafter referred as MORP). We then compare them to the calculation made. Our results clearly show that the new methodology is able to forecast the degree of deepening of meteoroids in the Earth's atmosphere. Then, this approach has important applications in predicting the impact hazard from cm- to meter-sized bodies that are represented, in part, in the MORP bolide list.

  14. Effects of Alloy Disorder on Schottky-Barrier Heights

    E-Print Network [OSTI]

    MYLES, CW; REN, SF; Allen, Roland E.; REN, SY.

    1987-01-01T23:59:59.000Z

    PHYSICAL REVIEW B VOLUME 35, NUMBER 18 15 JUNE 1987-II Effects of alloy disorder on Schottky-barrier heights Charles W. Myles Department of Physics and Engineering Physics, Texas Tech University, Lubbock, Texas 79409 Shang-Fen Ren* and Roland E...~ The effects of alloy disorder on the Schottky barriers at semiconductor-alloy ?metal interfaces are investigated within the defect model of Schottky-barrier formation. The deep levels and the associ- ated wave functions for surface antisite defects, which...

  15. Maximum Likelihood Haplotyping for General Pedigrees

    E-Print Network [OSTI]

    Friedman, Nir

    networks. The use of Bayesian networks enables efficient maximum likelihood haplotyping for more complex for the variables of the Bayesian network. The presented optimization algorithm also improves likelihood Analysis, Pedigree, superlink. Abstract Haplotype data is valuable in mapping disease-susceptibility genes

  16. Weak Scale From the Maximum Entropy Principle

    E-Print Network [OSTI]

    Yuta Hamada; Hikaru Kawai; Kiyoharu Kawana

    2014-09-23T23:59:59.000Z

    The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\\cal{O}}(300\\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \\begin{equation} v_{h}\\sim\\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\

  17. Weak Scale From the Maximum Entropy Principle

    E-Print Network [OSTI]

    Hamada, Yuta; Kawana, Kiyoharu

    2014-01-01T23:59:59.000Z

    The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\\cal{O}}(300\\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \\begin{equation} v_{h}\\sim\\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\

  18. Integrating Correlated Bayesian Networks Using Maximum Entropy

    SciTech Connect (OSTI)

    Jarman, Kenneth D.; Whitney, Paul D.

    2011-08-30T23:59:59.000Z

    We consider the problem of generating a joint distribution for a pair of Bayesian networks that preserves the multivariate marginal distribution of each network and satisfies prescribed correlation between pairs of nodes taken from both networks. We derive the maximum entropy distribution for any pair of multivariate random vectors and prescribed correlations and demonstrate numerical results for an example integration of Bayesian networks.

  19. Determining equivalent damage loading for full-scale wind turbine blade fatigue tests

    SciTech Connect (OSTI)

    Freebury, G.; Musial, W.

    2000-03-13T23:59:59.000Z

    This paper describes a simplified method for converting wind turbine rotor design loads into equivalent-damage, constant-amplitude loads and load ratios for both flap and lead-lag directions. It is an iterative method that was developed at the National Renewable Energy Laboratory (NREL) using Palmgren-Miner's linear damage principles. The general method is unique because it does not presume that any information about the materials or blade structural properties is precisely known. According to this method, the loads are never converted to stresses. Instead, a family of M-N curves (moment vs. cycles) is defined with reasonable boundaries for load-amplitude and slope. An optimization program iterates and converges on the constant amplitude test load and load ratio that minimizes the sensitivity to the range of M-N curves for each blade section. The authors constrained the general method to match the NedWind 25 design condition for the Standards, Measurements, and Testing (SMT) blade testing pro gram. SMT participants agreed to use the fixed S-N slope of m = 10 from the original design to produce consistent test-loads among the laboratories. Unconstrained, the general method suggests that slightly higher test loads should be used for the NedWind 25 blade design spectrum. NedWind 25 blade test loads were computed for lead-lag and flap under single-axis and two-axis loading.

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

    SciTech Connect (OSTI)

    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

    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.

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

    DOE Patents [OSTI]

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

    2013-12-10T23:59:59.000Z

    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.

  2. Stochastic model for aerodynamic force dynamics on wind turbine blades in unsteady wind inflow

    E-Print Network [OSTI]

    Luhur, Muhammad Ramzan; Kühn, Martin; Wächter, Matthias

    2015-01-01T23:59:59.000Z

    The paper presents a stochastic approach to estimate the aerodynamic forces with local dynamics on wind turbine blades in unsteady wind inflow. This is done by integrating a stochastic model of lift and drag dynamics for an airfoil into the aerodynamic simulation software AeroDyn. The model is added as an alternative to the static table lookup approach in blade element momentum (BEM) wake model used by AeroDyn. The stochastic forces are obtained for a rotor blade element using full field turbulence simulated wind data input and compared with the classical BEM and dynamic stall models for identical conditions. The comparison shows that the stochastic model generates additional extended dynamic response in terms of local force fluctuations. Further, the comparison of statistics between the classical BEM, dynamic stall and stochastic models' results in terms of their increment probability density functions gives consistent results.

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

    SciTech Connect (OSTI)

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

    2010-10-30T23:59:59.000Z

    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.

  4. QCD Level Density from Maximum Entropy Method

    E-Print Network [OSTI]

    Shinji Ejiri; Tetsuo Hatsuda

    2005-09-24T23:59:59.000Z

    We propose a method to calculate the QCD level density directly from the thermodynamic quantities obtained by lattice QCD simulations with the use of the maximum entropy method (MEM). Understanding QCD thermodynamics from QCD spectral properties has its own importance. Also it has a close connection to phenomenological analyses of the lattice data as well as experimental data on the basis of hadronic resonances. Our feasibility study shows that the MEM can provide a useful tool to study QCD level density.

  5. Tissue Radiation Response with Maximum Tsallis Entropy

    SciTech Connect (OSTI)

    Sotolongo-Grau, O.; Rodriguez-Perez, D.; Antoranz, J. C.; Sotolongo-Costa, Oscar [UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain); UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain) and University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba); University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba)

    2010-10-08T23:59:59.000Z

    The expression of survival factors for radiation damaged cells is currently based on probabilistic assumptions and experimentally fitted for each tumor, radiation, and conditions. Here, we show how the simplest of these radiobiological models can be derived from the maximum entropy principle of the classical Boltzmann-Gibbs expression. We extend this derivation using the Tsallis entropy and a cutoff hypothesis, motivated by clinical observations. The obtained expression shows a remarkable agreement with the experimental data found in the literature.

  6. A global maximum power point tracking DC-DC converter

    E-Print Network [OSTI]

    Duncan, Joseph, 1981-

    2005-01-01T23:59:59.000Z

    This thesis describes the design, and validation of a maximum power point tracking DC-DC converter capable of following the true global maximum power point in the presence of other local maximum. It does this without the ...

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

    DOE Patents [OSTI]

    Wetzel, Kyle Kristopher (Lawrence, KS)

    2008-03-18T23:59:59.000Z

    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.

  8. 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 of unidirectional (0E) and ±45 stranded fabric layers, typical blade materials, vary significantly in tensile

  9. Experimental study of gas turbine blade film cooling and internal turbulated heat transfer at large Reynolds numbers

    E-Print Network [OSTI]

    Mhetras, Shantanu

    2009-06-02T23:59:59.000Z

    on Blade Span under No Wake .....52 3.5.2. Showerhead Film Cooling Effectiveness under No Wake.................................56 3.5.3. Film Cooling Effectiveness on Blade Span without Showerhead Ejection and without Wake... ..............................................................................................59 3.5.4. Film Cooling Effectiveness Distribution from Individual Row Ejection..........62 3.5.5. Effect of Stationary, Unsteady Wake on Full Coverage Film Cooling Effectiveness...

  10. The motion of kelp blades and the surface renewal model Ivy Huang, Jeffrey Rominger, and Heidi Nepf*

    E-Print Network [OSTI]

    Nepf, Heidi M.

    The motion of kelp blades and the surface renewal model Ivy Huang, Jeffrey Rominger, and Heidi Nepf* Massachusetts Institute of Technology, Cambridge, Massachusetts Abstract We consider how the flapping of kelp kelp blades of Laminaria saccharina, Macrocystis pyrifera, and Nereocystis luetkeana under uni

  11. Department of Energy and Mineral Engineering Spring Roller Design to Increase the Lifespan of Asphalt Compactor Wiper Blades

    E-Print Network [OSTI]

    Demirel, Melik C.

    the Lifespan of Asphalt Compactor Wiper Blades By: Thomas Krupa, Eric Resch, Phillip Yesenosky, John Marshall, Asset Kusmanov Overview Volvo CE's asphalt compactors have a polymer wiper blade that is used life. o The roller was tested five times as long as the wipers and never showed any change in diameter

  12. Numerical Analysis of Turbine Blade Cooling Ducts M.J. Noot and R.M.M. Mattheij

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    Numerical Analysis of Turbine Blade Cooling Ducts M.J. Noot and R.M.M. Mattheij Eindhoven, The Netherlands March 2, 1998 Abstract The cooling of turbine blades in turbines is enhanced by providing the quality of these cooling ducts. 1 Introduction Gas turbines play an important role in aviation

  13. Static and Fatigue Analysis of Wind Turbine Blades Subject to Cold Weather Conditions Using Finite Element Analysis

    E-Print Network [OSTI]

    Victoria, University of

    Static and Fatigue Analysis of Wind Turbine Blades Subject to Cold Weather Conditions Using Finite Turbine Blades Subject to Cold Weather Conditions Using Finite Element Analysis by Patricio Andres Lillo experienced in candi- date Canadian wind turbine deployment locations. The thesis then narrows its focus

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

    DOE Patents [OSTI]

    Wetzel, Kyle Kristopher

    2014-06-24T23:59:59.000Z

    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.

  15. Algorithms for processing ultrasonic echo data for height control systems

    E-Print Network [OSTI]

    Lin, Reng Rong

    1984-01-01T23:59:59.000Z

    . Appendix C-3. Appendix C-4. 80 81 86 89 92 98 103 108 114 118 120 VITA. 122 viii LIST OF TABLES TABLE Page 1. Profile mcdels for generated data. . ~ . . 27 2. Limitations for a single threshold locations with simulated data 35 3.... Limitations for a double threshold locations with simulated data 37 4. Effects of stalk height on the distance between thresholds of a double threshold. C 1(1 0~ 1 Oi 1500~ 154 ~ 1346) , 39 5. Effects of weight given to stalk and ground echo on WRA...

  16. Space variations in axis height of the jet stream core

    E-Print Network [OSTI]

    Leutwyler, Cooke Hearon

    1965-01-01T23:59:59.000Z

    , In addition to the overall in- crease in the number of flights, the advent of jet and turboprop airpla, nes makes the jet stream level, viz. , 25, 000 to 45, 000 ft, the most desirable level for fuel economy during flight. Once man began to move about...SPACE VARIATIONS IN AKIS HEIGHT OF THE JET STREAM CORE A Thesis By COOKE HEARON LEUTWYLER, CAPT USAF Submitted to the Graduate College of the Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...

  17. Effects of working arm heights and age on blood pressure

    E-Print Network [OSTI]

    Cahalane, Patrick Takeo

    1985-01-01T23:59:59.000Z

    Heights OLDER SUBJECTS YOUNGER SUBJECTS AVERAGE FOR TWO GROUPS MEAN STANDARD DE V I ATION RANGE MEAN STANDARD DE VIA T I 0 N RANGE MEAN KNEE LEVEL 14. 4 2. 5 11-22 15. 7 I . 9 I I - 20 15. 1 WAIST LEVEL 18. 3 2, 7 15- 25 20. 2 2. 7 15- 27 19. 3... LEVEL WAIST LEVEL 2. 44' OVERHEAD LEVEL 3. 00' WAIST LEVEL VS. OVE, AHEAD LEVEL WAIST LEVEL VS. KNEE LEVEL OVERHEAD LEVEL VS, KNEE LEVEL WAIST LEVEL VS. STANDING (RESTING) 14. 70' 16. 00' 0. 35 21. 60' 19. 80' 5. 30...

  18. Plant community composition and vegetation height, Barrow, Alaska, Ver. 1

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sloan, Victoria; Norby, Richard; Siegrist, Julia; Iversen, Colleen; Brooks, Jonathan; Liebig, Jennifer; Wood, Sarah

    This dataset contains i) the results of field surveys of plant community composition and vegetation height made between 17th and 29th July 2012 in 48, 1 x 1 m plots located in areas A-D of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska and ii) results of a mapping exercise undertaken in August 2013 using two perpendicular transects across each polygon containing vegetation plots to determine the boundaries of vegetation communities described in 2012.

  19. Plant community composition and vegetation height, Barrow, Alaska, Ver. 1

    SciTech Connect (OSTI)

    Sloan, Victoria; Norby, Richard; Siegrist, Julia; Iversen, Colleen; Brooks, Jonathan; Liebig, Jennifer; Wood, Sarah

    2014-04-25T23:59:59.000Z

    This dataset contains i) the results of field surveys of plant community composition and vegetation height made between 17th and 29th July 2012 in 48, 1 x 1 m plots located in areas A-D of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska and ii) results of a mapping exercise undertaken in August 2013 using two perpendicular transects across each polygon containing vegetation plots to determine the boundaries of vegetation communities described in 2012.

  20. Airway Heights, Washington: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlinPapersWindeySanta2004)Airway Heights, Washington: Energy Resources

  1. Braddock Heights, Maryland: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomass ConversionsSouthbyBoston Heights,Boyne City, Michigan:BrackenBradBraddock

  2. Broadview Heights, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomassSustainable and Innovative EnergyHeights, Ohio: Energy Resources Jump to:

  3. Brooklyn Heights, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomassSustainable and Innovative EnergyHeights,Illinois:Brooklyn Center,

  4. Wheatley Heights, New York: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown ofNationwideWTED JumpHills,2732°,Wetzel County,Wheatley Heights, New York:

  5. Windsor Heights, Iowa: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown ofNationwideWTEDBird,Wilsonville, Oregon:WindPole VenturesNewHeights, Iowa:

  6. Champion Heights, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model, click here.Telluric Survey asWest,CEI Jump to:CerionChagrinChampaignJumpHeights,

  7. Property:GBIG/MinHeight | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag Jump to: navigation, search PropertyCalculatedCenter Jump to:MinHeight Jump to:

  8. Harwood Heights, Illinois: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetec AG| OpenInformationHartsville, New York: EnergyHarwood Heights,

  9. Holiday Heights, New Jersey: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel Jump to: navigation,Jersey:Heights, New Jersey: Energy Resources Jump

  10. Huber Heights, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel Jump to:Pennsylvania:County,Ohio: Energy ResourcesHuber Heights,

  11. Yorktown Heights, New York: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin: EnergyWyandanch, NewYanceyYokayoYorktown Heights, New York:

  12. Preston Heights, Illinois: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:Precourt Institute for EnergyWister Area (DOE GTP)Heights, Illinois:

  13. Glendale Heights, Illinois: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetec AG Contracting Jump to:Echo, Maryland: Energy ResourcesNewGlencoeHeights,

  14. South Chicago Heights, Illinois: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries Pvt LtdShawangunk, NewSingaporeSonix Japan IncInformation SouthHeights,

  15. Olympia Heights, Florida: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal Pwer PlantMunhall,Missouri: EnergyExcellenceOffice ofInformation OlkariaHeights, Florida:

  16. Madison Heights, Michigan: Energy Resources | Open Energy Information

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    Open Energy Info (EERE)

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  18. Taft Heights, California: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

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  19. Day Heights, Ohio: Energy Resources | Open Energy Information

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  20. Boston Heights, Ohio: Energy Resources | Open Energy Information

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  1. Rowland Heights, California: Energy Resources | Open Energy Information

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  2. Ford Heights, Illinois: Energy Resources | Open Energy Information

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  3. Garfield Heights, Ohio: Energy Resources | Open Energy Information

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  4. Cleveland Heights, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

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  5. Qualification of a Glassy Carbon Blade for a LHC Fast Vacuum Valve

    E-Print Network [OSTI]

    Garion, C

    2013-01-01T23:59:59.000Z

    To protect sensitive LHC machine systems against an unexpected gas inrush, a fast vacuum valve system is under development at CERN. The design of the shutter has to be compatible with dynamic loads occurring during the fast closure, namely in the 20 ms range. The material has to fulfil all main requirements such as transparency, high melting temperature, dust free and adequate leak tightness. A development of a blade in vitreous carbon material has been carried out at CERN. The blade has been successfully integrated in a commercial pendulum fast valve. In this paper, the vacuum and mechanical qualification tests are presented.

  6. Supply Chain and Blade Manufacturing Considerations in the Global Wind Industry (Presentation)

    SciTech Connect (OSTI)

    James, T.; Goodrich, A.

    2013-12-01T23:59:59.000Z

    This briefing provides an overview of supply chain developments in the global wind industry and a detailed assessment of blade manufacturing considerations for U.S. end-markets. The report discusses the international trade flows of wind power equipment, blade manufacturing and logistical costs, and qualitative issues that often influence factory location decisions. To help guide policy and research and development strategy decisions, this report offers a comprehensive perspective of both quantitative and qualitative factors that affect selected supply chain developments in the growing wind power industry.

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

    SciTech Connect (OSTI)

    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

    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.

  8. NedWind 25 Blade Testing at NREL for the European Standards Measurement and Testing Program

    SciTech Connect (OSTI)

    Larwood, S.; Musial, W.; Freebury, G.; Beattie, A.G.

    2001-04-19T23:59:59.000Z

    In the mid-90s the European community initiated the Standards, Measurements, and Testing (SMT) program to harmonize testing and measurement procedures in several industries. Within the program, a project was carried out called the European Wind Turbine Testing Procedure Development. The second part of that project, called Blade Test Methods and Techniques, included the United States and was devised to help blade-testing laboratories harmonize their testing methods. This report provides the results of those tests conducted by the National Renewable Energy Laboratory.

  9. articulatorily constrained maximum: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    weight spanning forests. Amitabha Bagchi; Ankur Bhargava; Torsten Suel 2005-01-01 27 Maximum Entropy Correlated Equilibria MIT - DSpace Summary: We study maximum entropy...

  10. U.S. Wind Manufacturing: Taller Hub Heights to Access Higher...

    Broader source: Energy.gov (indexed) [DOE]

    U.S. Wind Manufacturing: Taller Hub Heights to Access Higher Wind Resources and Lower Cost of Energy U.S. Wind Manufacturing: Taller Hub Heights to Access Higher Wind Resources and...

  11. Studies of the 3D surface roughness height

    SciTech Connect (OSTI)

    Avisane, Anita; Rudzitis, Janis; Kumermanis, Maris [Institute of Mechanical Engineering, Riga Technical University, Ezermalas str. 6k, Riga (Latvia)

    2013-12-16T23:59:59.000Z

    Nowadays nano-coatings occupy more and more significant place in technology. Innovative, functional coatings acquire new aspects from the point of view of modern technologies, considering the aggregate of physical properties that can be achieved manipulating in the production process with the properties of coatings’ surfaces on micro- and nano-level. Nano-coatings are applied on machine parts, friction surfaces, contacting parts, corrosion surfaces, transparent conducting films (TCF), etc. The equipment available at present for the production of transparent conducting oxide (TCO) coatings with highest quality is based on expensive indium tin oxide (ITO) material; therefore cheaper alternatives are being searched for. One such offered alternative is zink oxide (ZnO) nano-coatings. Evaluating the TCF physical and mechanical properties and in view of the new ISO standard (EN ISO 25178) on the introduction of surface texture (3D surface roughness) in the engineering calculations, it is necessary to examine the height of 3D surface roughness, which is one of the most significant roughness parameters. The given paper studies the average values of 3D surface roughness height and the most often applied distribution laws are as follows: the normal distribution and Rayleigh distribution. The 3D surface is simulated by a normal random field.

  12. Effect of Height (Fresnel Clearance) on Signal Strength and Throughput for

    E-Print Network [OSTI]

    Liblit, Ben

    Effect of Height (Fresnel Clearance) on Signal Strength and Throughput for Medium and Long Distance obstruction height · Ignoring Fresnel Clearance For 20Km long Wireless Link, Fresnel Clearance requires around, height 4 m at Q ensures 100% Fresnel Clearance On Physical Inspection: No LOS even at 8 meters Distance

  13. Conductivity maximum in a charged colloidal suspension

    SciTech Connect (OSTI)

    Bastea, S

    2009-01-27T23:59:59.000Z

    Molecular dynamics simulations of a charged colloidal suspension in the salt-free regime show that the system exhibits an electrical conductivity maximum as a function of colloid charge. We attribute this behavior to two main competing effects: colloid effective charge saturation due to counterion 'condensation' and diffusion slowdown due to the relaxation effect. In agreement with previous observations, we also find that the effective transported charge is larger than the one determined by the Stern layer and suggest that it corresponds to the boundary fluid layer at the surface of the colloidal particles.

  14. Sonic IR crack detection of aircraft turbine engine blades with multi-frequency ultrasound excitations

    SciTech Connect (OSTI)

    Zhang, Ding; Han, Xiaoyan [Department of Electrical and Computer Engineering, Wayne State University, Detroit, MI 48202 (United States); Newaz, Golam [Department of Mechanical Engineering, Wayne State University, Detroit, MI 48202 (United States)

    2014-02-18T23:59:59.000Z

    Effectively and accurately detecting cracks or defects in critical engine components, such as turbine engine blades, is very important for aircraft safety. Sonic Infrared (IR) Imaging is such a technology with great potential for these applications. This technology combines ultrasound excitation and IR imaging to identify cracks and flaws in targets. In general, failure of engine components, such as blades, begins with tiny cracks. Since the attenuation of the ultrasound wave propagation in turbine engine blades is small, the efficiency of crack detection in turbine engine blades can be quite high. The authors at Wayne State University have been developing the technology as a reliable tool for the future field use in aircraft engines and engine parts. One part of the development is to use finite element modeling to assist our understanding of effects of different parameters on crack heating while experimentally hard to achieve. The development has been focused with single frequency ultrasound excitation and some results have been presented in a previous conference. We are currently working on multi-frequency excitation models. The study will provide results and insights of the efficiency of different frequency excitation sources to foster the development of the technology for crack detection in aircraft engine components.

  15. Model reduction applied to multi-stage assemblies of bladed disks

    E-Print Network [OSTI]

    Boyer, Edmond

    or parametric modelling (rotation, temperature effects,...) can be carried out with more complex models. In bothModel reduction applied to multi-stage assemblies of bladed disks A. Sternch¨uss, E. Balm´e Ravaud, 77550 Moissy-Cramayel Cedex, France Abstract This paper deals with model reduction of assemblies

  16. Development and Analysis of a Swept Blade Aeroelastic Model for a Small Wind Turbine (Presentation)

    SciTech Connect (OSTI)

    Preus, R.; Damiani, R.; Lee, S.; Larwood, S.

    2014-06-01T23:59:59.000Z

    As part of the U.S. Department-of-Energy-funded Competitiveness Improvement Project, the National Renewable Energy Laboratory (NREL) developed new capabilities for aeroelastic modeling of precurved and preswept blades for small wind turbines. This presentation covers the quest for optimized rotors, computer-aided engineering tools, a case study, and summary of the results.

  17. NUMERICAL STUDY OF FLOW STREAM IN A MINI VAWT WITH RELATIVE ROTATING BLADES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . (2001), Martin J. (1987)...): horizontal-axis wind turbine (HAWTs) and vertical-axis wind turbine (VAWTs, performance coefficient, unsteady simulation, VAWT, vertical axis, wind energy, pitch controlled blades electricity and more and more with a renewable energy source character. Power production from wind turbines

  18. Complex Non-Linear Modal Analysis for Mechanical Systems: Application to Turbomachinery Bladings With Friction

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -conservative mechanical systems is proposed. In particular, dry-friction non-linearities are considered although degrees-of-freedom example featuring dry-friction illustrates the method and highlights the effects of a turbomachinery blade, with dry-friction interfaces is proposed. In the latter, an original framework

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

    DOE Patents [OSTI]

    Moroz; Emilian Mieczyslaw (San Diego, CA) [San Diego, CA

    2008-06-03T23:59:59.000Z

    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.

  20. Modelling and Analysis of Multi-Stage Systems of Mistuned Bladed Disks Denis Laxaldea,, Christophe Pierrea

    E-Print Network [OSTI]

    turbine engines, which feature improved design and optimisation, lightweight material and increa of a successful design process. Structural uncertainty may be due to numerous factors such as material) quantification of uncertainties in complex computational models. In turbine engines rotating components (bladed

  1. DAMAGE DETECTION IN A WIND TURBINE BLADE BASED ON TIME SERIES Simon Hoell, Piotr Omenzetter

    E-Print Network [OSTI]

    Boyer, Edmond

    DAMAGE DETECTION IN A WIND TURBINE BLADE BASED ON TIME SERIES METHODS Simon Hoell, Piotr Omenzetter, the consequences are growing sizes of wind turbines (WTs) and erections in remote places, such as off in the past years, thus efficient energy harvesting becomes more important. For the sector of wind energy

  2. Blade-forced vibration effects in turbomachinery rotor-stator interaction

    E-Print Network [OSTI]

    Collard, Joseph Eugene

    2000-01-01T23:59:59.000Z

    This thesis presents the effects of blade-forced vibration in turbomachinery rotor-stator interaction. A quasi-three-dimensional multi-row analysis, based on an Euler/Navier-Stokes solver and a parallel computational algorithm, was used to simulate...

  3. Structural and Damage Assessment of Multi-Section Modular Hybrid Composite Wind Turbine Blade

    E-Print Network [OSTI]

    Nanami, Norimichi

    2014-07-25T23:59:59.000Z

    the size of wind turbines to generate higher power output. Typically, the larger/longer blade designs rely on hybrid material systems such as carbon and/or glass fiber (CF/GF) reinforced polymers to improve specific stiffness/strength and damage tolerance...

  4. Developing a DataBlade for a New Index Rasa Bliujute Simonas

    E-Print Network [OSTI]

    Kaiserslautern, Universität

    applications, the major DBMS vendors are stepping beyond uninterpreted binary large objects, termed BLOBs, and are beginning to offer extensibility features that allow external developers to extend the DBMS with, e extensible DBMS, in that the new DataBlade aims to achieve better performance, not just to add functionality

  5. AIAA-2003-0692 NEW FATIGUE DATA FOR W IND TURBINE BLADE M ATERIALS

    E-Print Network [OSTI]

    1 AIAA-2003-0692 NEW FATIGUE DATA FOR W IND TURBINE BLADE M ATERIALS John F. Mandell, Daniel D to the wind turbine industry in several areas: (a) very high cycle S-N data; (b) refined Goodman Diagram; (c the expected cycle range for turbines. While the data cannot be used directly in design due to the specialized

  6. Structural and Damage Assessment of Multi-Section Modular Hybrid Composite Wind Turbine Blade 

    E-Print Network [OSTI]

    Nanami, Norimichi

    2014-07-25T23:59:59.000Z

    the size of wind turbines to generate higher power output. Typically, the larger/longer blade designs rely on hybrid material systems such as carbon and/or glass fiber (CF/GF) reinforced polymers to improve specific stiffness/strength and damage tolerance...

  7. Geek-Up[09.17.2010]-- Water Blades, Biomass Conversion and Antineutrino Detection

    Broader source: Energy.gov [DOE]

    Scientists have engineered a blade of water that’s strong enough and fast enough to penetrate through steel, which will help soldiers in Afghanistan disable deadly IEDs, plus researchers are currently testing an aboveground water-based antineutrino detector that will improve monitoring capabilities at nuclear facilities.

  8. A study of a cooling tower with variable packing heights 

    E-Print Network [OSTI]

    Khan, A. M. M. Farid

    1957-01-01T23:59:59.000Z

    for the uc;x oe of . 'f ~'F. CF 'SC L'. . INC 2 August 1957 i ajor: ', iechanical Zn;. :tneering A Stud. ;; of a Coolinp, Tower with Variable Packin- Heights A Thesis li. Vi. Farid Khan Approved as to style and. content by: Chaxrman of Commi tee... the Departm;. nt i~lonth Year fLCI inc)'&lr ' JGL&)) 'n fi3 a J thor ', ;laili . . io ila&' ' I. ' ~)oi&al J ?'. )' e . I al, &Lip & vi &or Heal ' oA'c '&I'oup oI . e& Ds !:I&Ei 1''el Ills i. oi&I'I'ei jb : taei i&n for i'urili li&i 1. ?a& rial anu equip...

  9. The physics and chemistry of the Schottky barrier height

    SciTech Connect (OSTI)

    Tung, Raymond T., E-mail: rtung@brooklyn.cuny.edu [Department of Physics, Brooklyn College, CUNY, 2900 Bedford Avenue, Brooklyn, New York 11210, USA and Physics Ph.D. Program, The Graduate Center, CUNY, 365 Fifth Avenue, New York 10016 (United States)

    2014-03-15T23:59:59.000Z

    The formation of the Schottky barrier height (SBH) is a complex problem because of the dependence of the SBH on the atomic structure of the metal-semiconductor (MS) interface. Existing models of the SBH are too simple to realistically treat the chemistry exhibited at MS interfaces. This article points out, through examination of available experimental and theoretical results, that a comprehensive, quantum-mechanics-based picture of SBH formation can already be constructed, although no simple equations can emerge, which are applicable for all MS interfaces. Important concepts and principles in physics and chemistry that govern the formation of the SBH are described in detail, from which the experimental and theoretical results for individual MS interfaces can be understood. Strategies used and results obtained from recent investigations to systematically modify the SBH are also examined from the perspective of the physical and chemical principles of the MS interface.

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

    SciTech Connect (OSTI)

    David M. Wright; DOE Project Officer - Keith Bennett

    2007-07-31T23:59:59.000Z

    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.

  11. Maximum screening fields of superconducting multilayer structures

    E-Print Network [OSTI]

    Gurevich, Alex

    2015-01-01T23:59:59.000Z

    It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields $H_s$ of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness $\\sim 0.1\\; \\mu$m at the Nb surface could increase $H_s\\simeq 240$ mT of a clean Nb up to $H_s\\simeq 290$ mT. Optimized multilayers of Nb$_3$Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.

  12. Design of 9-meter carbon-fiberglass prototype blades : CX-100 and TX-100 : final project report.

    SciTech Connect (OSTI)

    Berry, Derek (TPI Composites, Inc., Warren, RI)

    2007-09-01T23:59:59.000Z

    TPI Composites, Inc. (TPI), Global Energy Concepts, LLC (GEC), and MDZ Consulting (MDZ) have collaborated on a project to design, manufacture, and test prototype carbon-fiberglass hybrid wind turbine blades of 9-m length. The project, funded by Sandia National Laboratories, involves prototype blades in both conventional (unidirectional spar fibers running along the blade span) and ''adaptive'' (carbon fibers in off-axis orientation to achieve bend-twist-coupling) configurations. After manufacture, laboratory testing is being conducted to determine the static and fatigue strength of the prototypes, in conjunction with field testing to evaluate the performance under operational conditions.

  13. Indium Growth and Island Height Control on Si Submonolayer Phases

    SciTech Connect (OSTI)

    Chen, Jizhou

    2009-05-09T23:59:59.000Z

    Nanotechnology refers any technique that involves about object with nanoscale (10{sup -9} m) or even smaller. It has become more and more important in recently years and has changed our world dramatically. Most of modern electronic devices today should thanks to the miniaturizing driven by development of nanotechnology. Recent years, more and more governments are investing huge amount of money in research related to nanotechnology. There are two major reasons that nanostructure is so fascinate. The first one is the miniaturizing. It is obvious that if we can make products smaller without losing the features, we can save the cost and increase the performance dramatically. For an example, the first computer in the world, ENIAC, which occupied several rooms, is less powerful than the cheapest calculator today. Today's chips with sizes of less than half an inch contain millions of basic units. All these should thank to the development of nanotechnology. The other reason is that when we come to nanoscale, there are many new effects due to the quantum effect which can't be found in large systems. For an example, quantum dots (QDs) are systems which sizes are below 1{micro}m(10{sup -6}m) and restricted in three dimensions. There are many interesting quantum effects in QDs, including discrete energy levels, and interdot coupling. Due to these properties and their small sizes, QDs have varies potential applications such as quantum computing, probe, light emitting device, solar cells, and laser. To meet the requirement of the nanoelectrical applications, the QDs must be grown highly uniformly because their property is highly dependent on their sizes. The major methods to grow uniform QDs include epitaxial, and lithograph. Lithography is a process to make patterns on a thin film by selectively removing certain parts of the film. Using this method, people have good control over size, location and spacing of QDs. For an example, the Extreme ultraviolet lithography (EUVL) have a wave length of 13.4nm so it can curve on the surface of an sample to make structure as small as the order of 10nm. however, lithograph usually causes permanent damages to the surface and in many cases the QDs are damaged during the lithograph and therefore result in high percentage of defects. Quantum size effect has attracted more and more interests in surface science due to many of its effects. One of its effects is the height preference in film growing and the resulting possibility of uniformly sized self-assemble nanostructure. The experiment of Pb islands on In 4x1 phase shows that both the height and the width can be controlled by proper growth conditions, which expands the growth dimensions from 1 to 2. This discover leads us to study the In/Pb interface. In Ch.3, we found that the Pb islands growing on In 4x1-Si(111) surface which have uniform height due to QSE and uniform width due to the constriction of In 4x1 lattice have unexpected stability. These islands are stable in even RT, unlike usual nanostructures on Pb/Si surface which are stable only at low temperature. Since similar structures are usually grown at low temperature, this discovery makes the grown structures closer to technological applications. It also shows the unusual of In/Pb interface. Then we studied the In islands grown on Pb-{alpha}-{radical}3x{radical}3-Si(111) phase in Ch.4. These islands have fcc structure in the first few layers, and then convert to bct structure. The In fcc islands have sharp height preference due to QSE like Pb islands. However, the preferred height is different (7 layer for Pb on Si 7x7 and 4 layer for Pb on In 4x1), due to the difference of interface. The In islands structure prefers to be bct than fcc with coverage increase. It is quantitatively supported by first-principle calculation. Unexpectedly, the In islands grown on various of In interfaces didn't show QSE effects and phase transition from fcc and bct structures as on the Pb-{alpha} interface (Ch.6). In g(s) curve there is no clear oscillations in the g(s) curve as the In on Pb-{alpha} phase. This

  14. Control of a pulse height analyzer using an RDX workstation

    SciTech Connect (OSTI)

    Montelongo, S.; Hunt, D.N.

    1984-12-01T23:59:59.000Z

    The Nuclear Chemistry Division of Lawrence Livermore National laboratory is in the midst of upgrading its radiation counting facilities to automate data acquisition and quality control. This upgrade requires control of a pulse height analyzer (PHA) from an interactive LSI-11/23 workstation running RSX-11M. The PHA is a micro-computer based multichannel analyzer system providing data acquisition, storage, display, manipulation and input/output from up to four independent acquisition interfaces. Control of the analyzer includes reading and writing energy spectra, issuing commands, and servicing device interrupts. The analyzer communicates to the host system over a 9600-baud serial line using the Digital Data Communications link level Protocol (DDCMP). We relieved the RSX workstation CPU from the DDCMP overhead by implementing a DEC compatible in-house designed DMA serial line board (the ISL-11) to communicate with the analyzer. An RSX I/O device driver was written to complete the path between the analyzer and the RSX system by providing the link between the communication board and an application task. The I/O driver is written to handle several ISL-11 cards all operating in parallel thus providing support for control of multiple analyzers from a single workstation. The RSX device driver, its design and use by application code controlling the analyzer, and its operating environment will be discussed.

  15. Maximum Entropy Method Approach to $?$ Term

    E-Print Network [OSTI]

    Masahiro Imachi; Yasuhiko Shinno; Hiroshi Yoneyama

    2004-06-09T23:59:59.000Z

    In Monte Carlo simulations of lattice field theory with a $\\theta$ term, one confronts the complex weight problem, or the sign problem. This is circumvented by performing the Fourier transform of the topological charge distribution $P(Q)$. This procedure, however, causes flattening phenomenon of the free energy $f(\\theta)$, which makes study of the phase structure unfeasible. In order to treat this problem, we apply the maximum entropy method (MEM) to a Gaussian form of $P(Q)$, which serves as a good example to test whether the MEM can be applied effectively to the $\\theta$ term. We study the case with flattening as well as that without flattening. In the latter case, the results of the MEM agree with those obtained from the direct application of the Fourier transform. For the former, the MEM gives a smoother $f(\\theta)$ than that of the Fourier transform. Among various default models investigated, the images which yield the least error do not show flattening, although some others cannot be excluded given the uncertainty related to statistical error.

  16. Hydrodynamic and transport phenomena at the interface between flow and aquatic vegetation : from the forest to the blade scale

    E-Print Network [OSTI]

    Rominger, Jeffrey T. (Jeffrey Tsaros)

    2014-01-01T23:59:59.000Z

    From the canopy scale to the blade scale, interactions between fluid motion and kelp produce a wide array of hydrodynamic and scalar transport phenomena. At the kilometer scale of the kelp forest, coastal currents transport ...

  17. Investigation of Dynamic Aerodynamics and Control of Wind Turbine Sections Under Relevant Inflow/Blade Attitude Conditions

    SciTech Connect (OSTI)

    Naughton, Jonathan W. [University of Wyoming

    2014-08-05T23:59:59.000Z

    The growth of wind turbines has led to highly variable loading on the blades. Coupled with the relative reduced stiffness of longer blades, the need to control loading on the blades has become important. One method of controlling loads and maximizing energy extraction is local control of the flow on the wind turbine blades. The goal of the present work was to better understand the sources of the unsteady loading and then to control them. This is accomplished through an experimental effort to characterize the unsteadiness and the effect of a Gurney flap on the flow, as well as an analytical effort to develop control approaches. It was planned to combine these two efforts to demonstrate control of a wind tunnel test model, but that final piece still remains to be accomplished.

  18. Maximum Throughput Power Control in CDMA Wireless Networks

    E-Print Network [OSTI]

    Mellor-Crummey, John

    Maximum Throughput Power Control in CDMA Wireless Networks Anastasios Giannoulis Department introduce cross­layer, distributed power control algorithms that guarantee maximum possible data throughput performing dynamic routing and scheduling together with power control. The cross­layer interaction consists

  19. A study of potential flow through the blade profile of a rotodynamic machine by an electrically conducting sheet analog

    E-Print Network [OSTI]

    Varadarajan, Rasipur Narasimha

    1960-01-01T23:59:59.000Z

    is called a blade cascade. Wind tunnel tests are costly and require expensive test equipment. Useful information- on particular profiles and cascade arrangements is available in the pub- lished reports. But the designer is frequently confronted...- perly designed airfoil always adjusts itself in such a manner that the velocity at the trailing edge is finite" would be satisfied. Method II: Only one flow passage between the two adjacent blade profiles was considered. Here, lift force (effect...

  20. Predicting Whole Forest Structure, Primary Productivity, and Biomass Density From Maximum Tree Size and Resource Limitations

    E-Print Network [OSTI]

    Kempes, Christopher P; Dooris, William; West, Geoffrey B

    2015-01-01T23:59:59.000Z

    In the face of uncertain biological response to climate change and the many critiques concerning model complexity it is increasingly important to develop predictive mechanistic frameworks that capture the dominant features of ecological communities and their dependencies on environmental factors. This is particularly important for critical global processes such as biomass changes, carbon export, and biogenic climate feedback. Past efforts have successfully understood a broad spectrum of plant and community traits across a range of biological diversity and body size, including tree size distributions and maximum tree height, from mechanical, hydrodynamic, and resource constraints. Recently it was shown that global scaling relationships for net primary productivity are correlated with local meteorology and the overall biomass density within a forest. Along with previous efforts, this highlights the connection between widely observed allometric relationships and predictive ecology. An emerging goal of ecological...

  1. An investigation of the effects of luminaire mounting height on roadside sign placement and visibility

    E-Print Network [OSTI]

    Walton, Ned Ephram

    1966-01-01T23:59:59.000Z

    . ometer. . 21 V-1 Iso-footcand i. e Curve 30-foot Mounting Height. . . . . . . . . . . . . . . 28 Iso-footcandle Curve 40-foot Mount ing Height. . . . . . . . . . . . , . 29 V-3 Effects on Legibility Distance for C'ondit tons Shown... for Cond it rona Shown . 55 9-15 Sign Bright ress and Disabrlity Vetting Brightness for Horditior. s Shown. 56 V- 16 Sign Brigncness and Disability Veiling Brightness for 30- and 40- foot. Mounting Heights. . . . . . . . . . . . . . v-17 Sign...

  2. A comparison of predicted wind turbine blade loads to test measurements

    SciTech Connect (OSTI)

    Wright, A.D.; Thresher, R.W.

    1987-01-01T23:59:59.000Z

    The accurate prediction of wind turbine blade loads and response is important in predicting the fatigue life of wind machines. At the SERI Wind Energy Research Center, a rotor code called FLAP (Force and Loads Analysis Program) is currently being validated by comparing predicted results to machine measurements. The FLAP code has been modified to allow the teetering degrees of freedom. This paper describes these modifications and comparisons of predicted blade bending moments to test measurements. Wind tunnel data for a 1/20th scale model will be used to compare FLAP predictions for the cyclic flap-bending moments at the 33% spanwise station for three different wind speeds. The comparisons will be made for both rigid and teetering hubs. Currently, the FLAP code accounts for deterministic excitations such as wind shear, tower shadow, gravity, and prescribed yawing motions. Conclusions will be made regarding the code's accuracy in predicting the cyclic bending moments.

  3. Sustainable Energy Solutions Task 4.2: UV Degradation Prevention on Fiber-Reinforced Composite Blades

    SciTech Connect (OSTI)

    Janet M. Twomey, PhD

    2010-04-30T23:59:59.000Z

    EXECUTIVE SUMARRY Use of wind energy has expanded very quickly because of the energy prices, environmental concerns and improved efficiency of wind generators. Rather than using metal and alloy based wind turbine blades, larger size fiber (glass and carbon) reinforced composite blades have been recently utilized to increase the efficiency of the wind energy in both high and low wind potential areas. In the current composite manufacturing, pre-preg and vacuum-assisted/heat sensitive resin transfer molding and resin infusion methods are employed. However, these lighter, stiffer and stronger composite blades experience ultraviolet (UV) light degradation where polymers (epoxies and hardeners) used for the blades manufacturing absorb solar UV lights, and cause photolytic, thermo-oxidative and photo-oxidative reactions resulting in breaking of carbon-hydrogen bonds, polymer degradation and internal and external stresses. One of the main reasons is the weak protective coatings/paints on the composite blades. This process accelerates the aging and fatigue cracks, and reduces the overall mechanical properties of the blades. Thus, the lack of technology on coatings for blade manufacturing is forcing many government agencies and private companies (local and national windmill companies) to find a better solution for the composite wind blades. Kansas has a great wind potential for the future energy demand, so efficient wind generators can be an option for continuous energy production. The research goal of the present project was to develop nanocomposite coatings using various inclusions against UV degradation and corrosion, and advance the fundamental understanding of degradation (i.e., physical, chemical and physiochemical property changes) on those coatings. In pursuit of the research goal, the research objective of the present program was to investigate the effects of UV light and duration on various nanocomposites made mainly of carbon nanotubes and graphene nanoflakes, contribute the valuable information to this emerging field of advanced materials and manufacturing and advance the Kansas economy through creation of engineering knowledge and products in the wind energy. The proposed work was involved in a multidisciplinary research program that incorporates nanocomposite fabrication, advanced coating, characterization, surface and colloidal chemistry, physicochemistry, corrosion science, and analysis with a simple and effective testing methodology. The findings were closely related to our hypothesis and approaches that we proposed in this proposal. The data produced in the study offered to advance the physical understanding of the behavior of nanostructured materials for the prevention of UV light at different exposure time and salt fogging. Founding of this proposal enabled the first UV resistive nanocomposite corrosion coating effort in Kansas to impact the local and national wind mill industry. Results of this program provided valuable opportunities for the multidisciplinary training of undergraduate and graduate students at Wichita State University (WSU), as well as a number of aircraft companies (e.g., Cessna, Hawker Beechcraft, Spirit, Boeing and Bombardier/Learjet) and other local and regional industries.

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

    SciTech Connect (OSTI)

    Barone, Matthew Franklin

    2011-08-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Francis A. Di Bella

    2010-06-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    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

    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.

  7. GMM Estimation of a Maximum Entropy Distribution with Interval Data

    E-Print Network [OSTI]

    Perloff, Jeffrey M.

    GMM Estimation of a Maximum Entropy Distribution with Interval Data Ximing Wu* and Jeffrey M estimate it using a simple yet flexible maximum entropy density. Our Monte Carlo simulations show that the proposed maximum entropy density is able to approximate various distributions extremely well. The two

  8. Wind Shear and Turbulence Profiles at Elevated Heights: Great Lakes and Midwest Sites (Poster)

    SciTech Connect (OSTI)

    Elliott, D.; Schwartz, M.; Scott, G.

    2009-05-01T23:59:59.000Z

    Analyzed wind resource characteristics at elevated heights (50 m-200+m) incuding shear and turbulence profiles for some areas of the Great Lakes and M idwest sites.

  9. Fish Passage though Hydropower Turbines: Simulating Blade Strike using the Discrete Element Method

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Romero Gomez, Pedro DJ

    2014-12-08T23:59:59.000Z

    mong the hazardous hydraulic conditions affecting anadromous and resident fish during their passage though turbine flows, two are believed to cause considerable injury and mortality: collision on moving blades and decompression. Several methods are currently available to evaluate these stressors in installed turbines, i.e. using live fish or autonomous sensor devices, and in reduced-scale physical models, i.e. registering collisions from plastic beads. However, a priori estimates with computational modeling approaches applied early in the process of turbine design can facilitate the development of fish-friendly turbines. In the present study, we evaluated the frequency of blade strike and nadir pressure environment by modeling potential fish trajectories with the Discrete Element Method (DEM) applied to fish-like composite particles. In the DEM approach, particles are subjected to realistic hydraulic conditions simulated with computational fluid dynamics (CFD), and particle-structure interactions—representing fish collisions with turbine blades—are explicitly recorded and accounted for in the calculation of particle trajectories. We conducted transient CFD simulations by setting the runner in motion and allowing for better turbulence resolution, a modeling improvement over the conventional practice of simulating the system in steady state which was also done here. While both schemes yielded comparable bulk hydraulic performance, transient conditions exhibited a visual improvement in describing flow variability. We released streamtraces (steady flow solution) and DEM particles (transient solution) at the same location from where sensor fish (SF) have been released in field studies of the modeled turbine unit. The streamtrace-based results showed a better agreement with SF data than the DEM-based nadir pressures did because the former accounted for the turbulent dispersion at the intake but the latter did not. However, the DEM-based strike frequency is more representative of blade-strike probability than the steady solution is, mainly because DEM particles accounted for the full fish length, thus resolving (instead of modeling) the collision event.

  10. Beamstrahlung Photon Load on the TESLA Extraction Septum Blade(LCC-0104)

    SciTech Connect (OSTI)

    Seryi, A

    2003-10-02T23:59:59.000Z

    This note describes work performed in the framework of the International Linear Collider Technical Review Committee [1] to estimate the power load on the TESLA extraction septum blade due to beamstrahlung photons. It is shown, that under realistic conditions the photon load can be several orders of magnitude higher than what was estimated in the TESLA TDR [2] for the ideal Gaussian beams, potentially representing a serious limitation of the current design.

  11. Simulating Blade-Strike on Fish passing through Marine Hydrokinetic Turbines

    SciTech Connect (OSTI)

    Romero Gomez, Pedro DJ; Richmond, Marshall C.

    2014-06-16T23:59:59.000Z

    The study reported here evaluated the occurrence, frequency, and intensity of blade strike of fish on an axial-flow marine hydrokinetic turbine by using two modeling approaches: a conventional kinematic formulation and a proposed Lagrangian particle- based scheme. The kinematic model included simplifying assumptions of fish trajectories such as distribution and velocity. The proposed method overcame the need for such simplifications by integrating the following components into a computational fluid dynamics (CFD) model: (i) advanced eddy-resolving flow simulation, (ii) generation of ambient turbulence based on field data, (iii) moving turbine blades in highly transient flows, and (iv) Lagrangian particles to mimic the potential fish pathways. The test conditions to evaluate the blade-strike probability and fish survival rate were: (i) the turbulent environment, (ii) the fish size, and (iii) the approaching flow velocity. The proposed method offered the ability to produce potential fish trajectories and their interaction with the rotating turbine. Depending upon the scenario, the percentile of particles that registered a collision event ranged from 6% to 19% of the released sample size. Next, by using a set of experimental correlations of the exposure-response of living fish colliding with moving blades, the simulated collision data were used as input variables to estimate the survival rate of fish passing through the operating turbine. The resulting survival rates were greater than 96% in all scenarios, which is comparable to or better than known survival rates for conventional hydropower turbines. The figures of strike probability and mortality rate were amplified by the kinematic model. The proposed method offered the advantage of expanding the evaluation of other mechanisms of stress and injury on fish derived from hydrokinetic turbines and related devices.

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

    SciTech Connect (OSTI)

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

    1995-06-01T23:59:59.000Z

    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.

  13. Evaluation of Blade-Strike Models for Estimating the Biological Performance of Large Kaplan Hydro Turbines

    SciTech Connect (OSTI)

    Deng, Zhiqun; Carlson, Thomas J.; Ploskey, Gene R.; Richmond, Marshall C.

    2005-11-30T23:59:59.000Z

    BioIndex testing of hydro-turbines is sought as an analog to the hydraulic index testing conducted on hydro-turbines to optimize their power production efficiency. In BioIndex testing the goal is to identify those operations within the range identified by Index testing where the survival of fish passing through the turbine is maximized. BioIndex testing includes the immediate tailrace region as well as the turbine environment between a turbine's intake trashracks and the exit of its draft tube. The US Army Corps of Engineers and the Department of Energy have been evaluating a variety of means, such as numerical and physical turbine models, to investigate the quality of flow through a hydro-turbine and other aspects of the turbine environment that determine its safety for fish. The goal is to use these tools to develop hypotheses identifying turbine operations and predictions of their biological performance that can be tested at prototype scales. Acceptance of hypotheses would be the means for validation of new operating rules for the turbine tested that would be in place when fish were passing through the turbines. The overall goal of this project is to evaluate the performance of numerical blade strike models as a tool to aid development of testable hypotheses for bioIndexing. Evaluation of the performance of numerical blade strike models is accomplished by comparing predictions of fish mortality resulting from strike by turbine runner blades with observations made using live test fish at mainstem Columbia River Dams and with other predictions of blade strike made using observations of beads passing through a 1:25 scale physical turbine model.

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

    SciTech Connect (OSTI)

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

    1980-11-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    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

    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.

  16. Results of the DF-4 BWR (boiling water reactor) control blade-channel box test

    SciTech Connect (OSTI)

    Gauntt, R.O.; Gasser, R.D.

    1990-10-01T23:59:59.000Z

    The DF-4 in-pile fuel damage experiment investigated the behavior of boiling water reactor (BWR) fuel canisters and control blades in the high temperature environment of an unrecovered reactor accident. This experiment, which was carried out in the Annular Core Research Reactor (ACRR) at Sandia National Laboratories, was performed under the USNRC's internationally sponsored severe fuel damage (SFD) program. The DF-4 test is described herein and results from the experiment are presented. Important findings from the DF-4 test include the low temperature melting of the stainless steel control blade caused by reaction with the B{sub 4}C, and the subsequent low temperature attack of the Zr-4 channel box by the relocating molten blade components. Hydrogen generation was found to continue throughout the experiment, diminishing slightly following the relocation of molten oxidizing zircaloy to the lower extreme of the test bundle. A large blockage which was formed from this material continued to oxidize while steam was being fed into the the test bundle. The results of this test have provided information on the initial stages of core melt progression in BWR geometry involving the heatup and cladding oxidation stages of a severe accident and terminating at the point of melting and relocation of the metallic core components. The information is useful in modeling melt progression in BWR core geometry, and provides engineering insight into the key phenomena controlling these processes. 12 refs., 12 figs.

  17. Enhancement of soft X-ray lasing action with thin blade radiators

    DOE Patents [OSTI]

    Suckewer, Szymon (Princeton Junction, NJ); Skinner, Charles H. (Kingston, NJ); Voorhees, David R. (Hopewell, NJ)

    1988-01-01T23:59:59.000Z

    An enhancement of approximately 100 of stimulated emission over spontaneous emission of the CVI 182 Angstrom line was obtained in a recombining magnetically confined plasma column. The plasma was formed by focusing a CO.sub.2 laser beam on a carbon disc. A magnetic solenoid produced a strong magnetic field which confined the plasma to the shape of a column. A single thin carbon blade extended parallel to the plasma column and served to make the column axially more uniform and also acted as a heat sink. Axial and transverse measurements of the soft X-ray lasing action were made from locations off-set from the central axis of the plasma column. Multiple carbon blades located at equal intervals around the plasma column were also found to produce acceptable results. According to another embodiment 10 a thin coating of aluminum or magnesium was placed on the carbon disc and blade. The Z of the coating should preferably be at least 5 greater than the Z of the target. Measurements of the soft X-rays generated at 182 Angstroms showed a significant increase in intensity enhancement.

  18. Nonlinear Legendre Spectral Finite Elements for Wind Turbine Blade Dynamics: Preprint

    SciTech Connect (OSTI)

    Wang, Q.; Sprague, M. A.; Jonkman, J.; Johnson, N.

    2014-01-01T23:59:59.000Z

    This paper presents a numerical implementation and examination of new wind turbine blade finite element model based on Geometrically Exact Beam Theory (GEBT) and a high-order spectral finite element method. The displacement-based GEBT is presented, which includes the coupling effects that exist in composite structures and geometric nonlinearity. Legendre spectral finite elements (LSFEs) are high-order finite elements with nodes located at the Gauss-Legendre-Lobatto points. LSFEs can be an order of magnitude more efficient that low-order finite elements for a given accuracy level. Interpolation of the three-dimensional rotation, a major technical barrier in large-deformation simulation, is discussed in the context of LSFEs. It is shown, by numerical example, that the high-order LSFEs, where weak forms are evaluated with nodal quadrature, do not suffer from a drawback that exists in low-order finite elements where the tangent-stiffness matrix is calculated at the Gauss points. Finally, the new LSFE code is implemented in the new FAST Modularization Framework for dynamic simulation of highly flexible composite-material wind turbine blades. The framework allows for fully interactive simulations of turbine blades in operating conditions. Numerical examples showing validation and LSFE performance will be provided in the final paper.

  19. Microscopic Description of Nuclear Fission: Fission Barrier Heights of Even-Even Actinides

    E-Print Network [OSTI]

    J. McDonnell; N. Schunck; W. Nazarewicz

    2013-01-31T23:59:59.000Z

    We evaluate the performance of modern nuclear energy density functionals for predicting inner and outer fission barrier heights and energies of fission isomers of even-even actinides. For isomer energies and outer barrier heights, we find that the self-consistent theory at the HFB level is capable of providing quantitative agreement with empirical data.

  20. A Perceptual Study on Haptic Rendering of Surface Topography when Both Surface Height and Stiffness Vary

    E-Print Network [OSTI]

    Tan, Hong Z.

    A Perceptual Study on Haptic Rendering of Surface Topography when Both Surface Height and Stiffness of surface topography when both surface height and surface stiffness vary. Three psychophysical experiments of haptic virtual environments. 1 Introduction How do people perceive the surface topography1 of a virtual

  1. Global Moderate Resolution Imaging Spectroradiometer (MODIS) cloud detection and height evaluation using CALIOP

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Global Moderate Resolution Imaging Spectroradiometer (MODIS) cloud detection and height evaluation Spectroradiometer (MODIS) cloud detection and height evaluation using CALIOP, J. Geophys. Res., 113, D00A19, doi:10] with plans to continue the cloud record using the next generation of polar orbiting sensors. A ``Climate

  2. DC's Marble ceiling : urban height and its regulation in Washington, DC

    E-Print Network [OSTI]

    Trueblood, Andrew Tyson

    2009-01-01T23:59:59.000Z

    Washington, DC has a unique urban form that is the result of a century-old law. Through the narrow lens of DC's height limit, I survey a range of topics related to urban height, starting with a review of its history of ...

  3. A Near Maximum Likelihood Decoding Algorithm for MIMO Systems ...

    E-Print Network [OSTI]

    Amin Mobasher

    2005-10-03T23:59:59.000Z

    Oct 3, 2005 ... A Near Maximum Likelihood Decoding Algorithm for MIMO Systems Based ... models are also used for soft output decoding in MIMO systems.

  4. Computing the Maximum Volume Inscribed Ellipsoid of a Polytopic ...

    E-Print Network [OSTI]

    Jianzhe Zhen

    2015-01-23T23:59:59.000Z

    Jan 23, 2015 ... Abstract: This paper introduces a method for computing the maximum volume inscribed ellipsoid and k-ball of a projected polytope. It is known ...

  5. Solving Maximum-Entropy Sampling Problems Using Factored Masks

    E-Print Network [OSTI]

    Samuel Burer

    2005-03-02T23:59:59.000Z

    Mar 2, 2005 ... Abstract: We present a practical approach to Anstreicher and Lee's masked spectral bound for maximum-entropy sampling, and we describe ...

  6. A masked spectral bound for maximum-entropy sampling

    E-Print Network [OSTI]

    Kurt Anstreicher

    2003-09-16T23:59:59.000Z

    Sep 16, 2003 ... Abstract: We introduce a new masked spectral bound for the maximum-entropy sampling problem. This bound is a continuous generalization of ...

  7. Maximum entropy generation in open systems: the Fourth Law?

    E-Print Network [OSTI]

    Umberto Lucia

    2010-11-17T23:59:59.000Z

    This paper develops an analytical and rigorous formulation of the maximum entropy generation principle. The result is suggested as the Fourth Law of Thermodynamics.

  8. annual maximum extent: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of the Sixteenth Annual Conference on Neural Information Processing Systems (NIPS2002) A Maximum Entropy Approach To Computer Technologies and Information Sciences Websites...

  9. analog fixed maximum: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    state for given entanglement which can be viewed as an analogue of the Jaynes maximum entropy principle. Pawel Horodecki; Ryszard Horodecki; Michal Horodecki 1998-05-22...

  10. IBM Research Report Solving Maximum-Entropy Sampling ...

    E-Print Network [OSTI]

    2005-02-28T23:59:59.000Z

    Feb 28, 2005 ... Solving Maximum-Entropy Sampling Problems Using. Factored Masks. Samuel Burer. Department of Management Sciences. University of Iowa.

  11. A Requirement for Significant Reduction in the Maximum BTU Input...

    Energy Savers [EERE]

    A Requirement for Significant Reduction in the Maximum BTU Input Rate of Decorative Vented Gas Fireplaces Would Impose Substantial Burdens on Manufacturers A Requirement for...

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

    SciTech Connect (OSTI)

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

    2011-01-04T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Chen, Chang

    2013-05-08T23:59:59.000Z

    SERR,G strain energy release rate E Young?s modulus of adherend Ea Young?s modulus of adhesive D exural rigidity of adherend Ga shear modulus of adhesive J J-integral K spring sti ness W strain energy density a coordinate of left side of void..., and will deteriorate the structural sti ness and strength, even cause catastrophic failure [23][25] (Fig. 1.12). Figure 1.12: Catastrophic eld failure of wind turbine During a typical-20-year service life, adhesively bonded joints in wind turbine blades...

  14. Appendix 22 Draft Nutrient Management Plan and Total Maximum Daily

    E-Print Network [OSTI]

    Appendix 22 Draft Nutrient Management Plan and Total Maximum Daily Load for Flathead Lake, Montana. #12;11/01/01 DRAFT i October 30, 2001 Draft Nutrient Management Plan and Total Maximum Daily Load..............................................................................................................................2-11 SECTION 3.0 APPLICABLE WATER QUALITY STANDARDS

  15. FAST SPEAKER ADAPTION VIA MAXIMUM PENALIZED LIKELIHOOD KERNEL REGRESSION

    E-Print Network [OSTI]

    Tsang Wai Hung "Ivor"

    of MLLR using non- linear regression. Specifically, kernel regression is applied with appropriate of Science and Technology Clear Water Bay, Hong Kong ABSTRACT Maximum likelihood linear regression (MLLR) has], and transformation-based methods, most notably, maximum likelihood linear regression (MLLR) adap- tation [3]. However

  16. Digital tomosynthesis mammography using a parallel maximum likelihood reconstruction method

    E-Print Network [OSTI]

    Meleis, Waleed

    Digital tomosynthesis mammography using a parallel maximum likelihood reconstruction method Tao Wu , a Radiology Department, Massachusetts General Hospital, Boston, MA 02114 b Dept. of Electrical and Computer on an iterative maximum likelihood (ML) algorithm, is developed to provide fast reconstruction for digital

  17. Results and phenomena observed from the DF-4 BWR (boiling water reactor) control blade-channel box test

    SciTech Connect (OSTI)

    Gauntt, R.O.; Gasser, R.D.; Fryer, C.P.; Walker, J.V.

    1988-01-01T23:59:59.000Z

    The DF-4 in-pile fuel damage experiment, one of a series of tests performed as part of the USNRC's internationally sponsored severe fuel damage (SFD) program, and carried out at Sandia National Laboratories, addressed the behavior of boiling water reactor (BWR) fuel canisters and control blades in the high temperature environment of an unrecovered loss of coolant accident. The DF-4 test is described in some detail herein and results from the experiment are presented. Significant results from prior experiments in the series are also summarized. Important findings from the DF-4 test include the low temperature melting of the stainless steel control blade caused by reaction with the B/sub 4/C, and the subsequent low temperature attack of the Zr-4 channel box by the relocating molten blade components. This early melt and relocation phenomena could significantly influence the progression of meltdown in BWRs and should be considered in SFD accident analyses. 14 refs., 9 figs.

  18. Development and Validation of a New Blade Element Momentum Skewed-Wake Model within AeroDyn: Preprint

    SciTech Connect (OSTI)

    Ning, S. A.; Hayman, G.; Damiani, R.; Jonkman, J.

    2014-12-01T23:59:59.000Z

    Blade element momentum methods, though conceptually simple, are highly useful for analyzing wind turbines aerodynamics and are widely used in many design and analysis applications. A new version of AeroDyn is being developed to take advantage of new robust solution methodologies, conform to a new modularization framework for National Renewable Energy Laboratory's FAST, utilize advanced skewed-wake analysis methods, fix limitations with previous implementations, and to enable modeling of highly flexible and nonstraight blades. This paper reviews blade element momentum theory and several of the options available for analyzing skewed inflow. AeroDyn implementation details are described for the benefit of users and developers. These new options are compared to solutions from the previous version of AeroDyn and to experimental data. Finally, recommendations are given on how one might select from the various available solution approaches.

  19. 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]

    systems by testing a blade from one of Clipper Windpower's 2.5-megawatt wind turbines. Photo by DerekThe new Wind Technology Test Center is the only facility in the nation capable of testing wind turbine blades up to 90 meters in length. A critical factor to wind turbine design and development

  20. Height change detection in Antarcita using satellite altimetry data and Kriging / Kalman filtering techniques

    E-Print Network [OSTI]

    Nguyen, An Thanh-Thuy

    2006-01-01T23:59:59.000Z

    Studies of the response of ice sheets to climate change require data sets with high accuracy and uniform ice-sheet coverage. The most common technique used in analyzing satellite altimetry data to study height change in ...

  1. Real-time variable rate Pix® application system using a plant height sensor 

    E-Print Network [OSTI]

    Beck, Andy Dwayne

    2001-01-01T23:59:59.000Z

    . A cotton growth regulator (Pix) was applied at uniform and biomass-based variable rates in a replicated study that included two cotton fields. Plant mapping data was collected during the season. Plant heights were significantly shorter in areas...

  2. Extending the utility of machine based height sensors to spatially monitor cotton growth 

    E-Print Network [OSTI]

    Geiger, David William

    2004-09-30T23:59:59.000Z

    The recommended procedures for implementing COTMAN; a cotton management expert system; suggest frequent crop scouting at numerous locations for each field. Machine based height sensors coupled with the ability to spatially ...

  3. BeamDyn: A High-Fidelity Wind Turbine Blade Solver in the FAST Modular Framework: Preprint

    SciTech Connect (OSTI)

    Wang, Q.; Sprague, M.; Jonkman, J.; Johnson, N.

    2015-01-01T23:59:59.000Z

    BeamDyn, a Legendre-spectral-finite-element implementation of geometrically exact beam theory (GEBT), was developed to meet the design challenges associated with highly flexible composite wind turbine blades. In this paper, the governing equations of GEBT are reformulated into a nonlinear state-space form to support its coupling within the modular framework of the FAST wind turbine computer-aided engineering (CAE) tool. Different time integration schemes (implicit and explicit) were implemented and examined for wind turbine analysis. Numerical examples are presented to demonstrate the capability of this new beam solver. An example analysis of a realistic wind turbine blade, the CX-100, is also presented as validation.

  4. Evaluating stereoscopic CCD still video imagery for determining object height in forestry applications

    E-Print Network [OSTI]

    Jacobs, Dennis Murray

    1990-01-01T23:59:59.000Z

    EVALUATING STEREOSCOPIC CCD STILL VIDEO IMAGERY FOR DETERMINING OBJECT HEIGHT IN FORESTRY APPLICATIONS A Thesis by DENNIS MURRAY JACOBS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1990 Major Subject: Forestry EVALUATING STEREOSCOPIC CCD STILL VIDEO IMAGERY FOR DETERMINING OBJECT HEIGHT IN FORESTRY APPLICATIONS A Thesis by DENNIS MURRAY JACOBS Approved as to style...

  5. Gas turbine blade materials' corrosion in the effluent from a pressurized fluidized bed combustor

    SciTech Connect (OSTI)

    Mc Carron, R.L.; Brobst, R.P.

    1984-06-01T23:59:59.000Z

    Two nominally 200-hour tests were conducted in the General Electric Company's Pressurized Fluidized Bed (PFB) Coal Combustion facility in Malta, NY. The purpose of the tests was to evaluate the influence of bed operating temperature and dolomite composition on the degradation of gas turbine vane and blade base alloys and protective coating/cladding systems in the effluent from a PFB. Operating conditions were as follows: 1710/sup 0/-1770/sup 0/F (932/sup 0/C-966/sup 0/C) bed temperature and Pfizer dolomite (0.1 wt% sodium plus potassium), and 1630/sup 0/-1690/sup 0/F (888/sup 0/-921/sup 0/C) bed temperature and Tymochtee dolomite (0.9 wt% sodium plus potassium). Brookville seam coal with 4.5 wt% sulfur, 0.3 wt% alkali, and 0.17 wt% chlorine was used in both tests. Bare nickel and cobalt-base vane and blade alloys were susceptible to hot corrosion over the entire temperature range investigated, 1100/sup 0/1600/sup 0/F (593/sup 0/-871/sup 0/C). CoCrAlY and FeCrAlY overlay coatings showed good corrosion resistance at temperatures above 1450/sup 0/F, but were susceptible to pitting attack at lower temperatures. A platinum-aluminide diffusion coating showed excellent corrosion resistance at all temperatures.

  6. ARM: ARSCL: cloud base height from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Coulter, Richard; Widener, Kevin; Bharadwaj, Nitin; Johnson, Karen; Martin, Timothy

    ARSCL: cloud base height from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

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

    SciTech Connect (OSTI)

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

    2010-09-01T23:59:59.000Z

    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

  8. SU-E-I-51: Use of Blade Sequences in Cervical Spine MR Imaging for Eliminating Motion, Truncation and Flow Artifacts

    SciTech Connect (OSTI)

    Mavroidis, P [University of Texas Health Science Center, UTHSCSA, San Antonio, TX (United States); Lavdas, E; Kostopoulos, S; Ninos, C; Strikou, A; Glotsos, D; Vlachopoulou, A; Oikonomou, G [Technological Education Institute of Athens, Athens, Athens (Greece); Economopoulos, N [General University Hospital ATTIKON, Athens, Athens (Greece); Roka, V [Health Center of Farkadona, Trikala (Greece); Sakkas, G [Center for Research and Technology of Thessaly, Trikala (Greece); Tsagkalis, A; Batsikas, G [IASO Thessalias Hospital, Larissa (Greece); Statkahis, S [Cancer Therapy and Research Center, San Antonio, TX (United States); Papanikolaou, N [University of Texas HSC SA, San Antonio, TX (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To assess the efficacy of the BLADE technique to eliminate motion, truncation, flow and other artifacts in Cervical Spine MRI compared to the conventional technique. To study the ability of the examined sequences to reduce the indetention and wrap artifacts, which have been reported in BLADE sagittal sequences. Methods: Forty consecutive subjects, who had been routinely scanned for cervical spine examination using four different image acquisition techniques, were analyzed. More specifically, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitative analysis was performed using the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and relative contrast (ReCon) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0:non-visualization; 1:poor; 2:average; 3:good; 4:excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). Results: Based on the findings of the quantitative analysis, the ReCON values of the CSF (cerebrospinal fluid)/SC (spinal cord) between TIRM SAG and TIRM SAG BLADE were found to present statistical significant differences (p<0.001). Regarding motion and truncation artifacts, the T2 TSE SAG BLADE was superior compared to the T2 TSE SAG and the T2 TIRM SAG BLADE was superior compared to the T2 TIRM SAG. Regarding flow artifacts, T2 TIRM SAG BLADE eliminated more artifacts compared to the T2 TIRM SAG. Conclusion: The use of BLADE sequences in cervical spine MR examinations appears to be capable of potentially eliminating motion, pulsatile flow and trancation artifacts. Furthermore, BLADE sequences are proposed to be used in the standard examination protocols based on the fact that a significantly improved image quality could be achieved.

  9. Linearized semiclassical initial value time correlation functions with maximum entropy analytic continuation

    E-Print Network [OSTI]

    Liu, Jian

    2008-01-01T23:59:59.000Z

    1992). J. Skilling, in Maximum entropy and Bayesian methods,1989). S. F. Gull, in Maximum entropy and Bayesian methods,with the classical maximum entropy (CME) technique (MEAC-

  10. Improved constraints on transit time distributions from argon 39: A maximum entropy approach

    E-Print Network [OSTI]

    Holzer, Mark; Primeau, Francois W

    2010-01-01T23:59:59.000Z

    Gull (1991), Bayesian maximum entropy image reconstruction,Atlantic venti- lated? Maximum entropy inversions of bottlefrom argon 39: A maximum entropy approach Mark Holzer 1,2

  11. Quantum Statistics Basis, Thermodynamic Analogies and the Degree of Confidence for Maximum Entropy Restoration and Estimation

    E-Print Network [OSTI]

    Soffer, Bernard H; Kikuchi, Ryoichi

    1994-01-01T23:59:59.000Z

    of Confidence for Maximum Entropy Restoration and EstimationApril 3, 1992) The Maximum Entropy method, using physicalare discussed. Maximum Entropy (ME) estimation has been

  12. Multichannel Blind Identification: From Subspace to Maximum Likelihood Methods

    E-Print Network [OSTI]

    Tong, Lang

    Multichannel Blind Identification: From Subspace to Maximum Likelihood Methods LANG TONG, MEMBER, IEEE, AND SYLVIE PERREAU Invited Paper A review of recent blind channel estimation algorithms is pre-- Blind equalization, parameter estimation, system identification. I. INTRODUCTION A. What Is Blind

  13. Maximum containment : the most controversial labs in the world

    E-Print Network [OSTI]

    Bruzek, Alison K. (Allison Kim)

    2013-01-01T23:59:59.000Z

    In 2002, following the September 11th attacks and the anthrax letters, the United States allocated money to build two maximum containment biology labs. Called Biosafety Level 4 (BSL-4) facilities, these labs were built to ...

  14. On the maximum pressure rise rate in boosted HCCI operation

    E-Print Network [OSTI]

    Wildman, Craig B.

    This paper explores the combined effects of boosting, intake air temperature, trapped residual gas fraction, and dilution on the Maximum Pressure Rise Rate (MPRR) in a boosted single cylinder gasoline HCCI engine with ...

  15. Maximum Photovoltaic Penetration Levels on Typical Distribution Feeders: Preprint

    SciTech Connect (OSTI)

    Hoke, A.; Butler, R.; Hambrick, J.; Kroposki, B.

    2012-07-01T23:59:59.000Z

    This paper presents simulation results for a taxonomy of typical distribution feeders with various levels of photovoltaic (PV) penetration. For each of the 16 feeders simulated, the maximum PV penetration that did not result in steady-state voltage or current violation is presented for several PV location scenarios: clustered near the feeder source, clustered near the midpoint of the feeder, clustered near the end of the feeder, randomly located, and evenly distributed. In addition, the maximum level of PV is presented for single, large PV systems at each location. Maximum PV penetration was determined by requiring that feeder voltages stay within ANSI Range A and that feeder currents stay within the ranges determined by overcurrent protection devices. Simulations were run in GridLAB-D using hourly time steps over a year with randomized load profiles based on utility data and typical meteorological year weather data. For 86% of the cases simulated, maximum PV penetration was at least 30% of peak load.

  16. Bacteria Total Maximum Daily Load Task Force Final Report 

    E-Print Network [OSTI]

    Jones, C. Allan; Wagner, Kevin; Di Giovanni, George; Hauck, Larry; Mott, Joanna; Rifai, Hanadi; Srinivasan, Raghavan; Ward, George; Wythe, Kathy

    2009-01-01T23:59:59.000Z

    In September 2006, the Texas Commission on Environmental Quality (TCEQ) and Texas State Soil and Water Conservation Board (TSSWCB) charged a seven-person Bacteria Total Maximum Daily Load (TMDL) Task Force with: * examining approaches...

  17. Maximum Likelihood Decoding of Reed Solomon Codes Madhu Sudan

    E-Print Network [OSTI]

    Sudan, Madhu

    Maximum Likelihood Decoding of Reed Solomon Codes Madhu Sudan Abstract We present a randomized and Welch [4] (see, for instance, Gem- mell and Sudan [9]). In this paper we present an algorithm which

  18. Multi-Class Classification with Maximum Margin Multiple Kernel

    E-Print Network [OSTI]

    Tomkins, Andrew

    (named OBSCURE and UFO-MKL, respectively) are used to optimize primal versions of equivalent problems), the OBSCURE and UFO-MKL algorithms are compared against MCMKL #12;Multi-Class Classification with Maximum

  19. Maximum entropy method and oscillations in the diffraction cone

    E-Print Network [OSTI]

    O. Dumbrajs; J. Kontros; A. Lengyel

    2000-07-15T23:59:59.000Z

    The maximum entropy method has been applied to investigate the oscillating structure in the pbarp- and pp-elastic scattering differential cross-section at high energy and small momentum transfer. Oscillations satisfying quite realistic reliability criteria have been found.

  20. Filtering Additive Measurement Noise with Maximum Entropy in the Mean

    E-Print Network [OSTI]

    Henryk Gzyl; Enrique ter Horst

    2007-09-04T23:59:59.000Z

    The purpose of this note is to show how the method of maximum entropy in the mean (MEM) may be used to improve parametric estimation when the measurements are corrupted by large level of noise. The method is developed in the context on a concrete example: that of estimation of the parameter in an exponential distribution. We compare the performance of our method with the bayesian and maximum likelihood approaches.

  1. The maximum entropy tecniques and the statistical description of systems

    E-Print Network [OSTI]

    B. Z. Belashev; M. K. Suleymanov

    2001-10-19T23:59:59.000Z

    The maximum entropy technique (MENT) is used to determine the distribution functions of physical values. MENT naturally combines required maximum entropy, the properties of a system and connection conditions in the form of restrictions imposed on the system. It can, therefore, be employed to statistically describe closed and open systems. Examples in which MENT is used to describe equilibrium and non-equilibrium states, as well as steady states that are far from being in thermodynamic equilibrium, are discussed.

  2. Eliciting a human understandable model of ice adhesion strength for rotor blade leading edge materials from uncertain experimental data

    E-Print Network [OSTI]

    Granada, Universidad de

    Eliciting a human understandable model of ice adhesion strength for rotor blade leading edge: Genetic Fuzzy Systems Fuzzy rule-based classifiers Vague data Isotropic materials Ice-phobic materials Shear adhesion strength a b s t r a c t The published ice adhesion performance data of novel ``ice

  3. Effect of film hole location on heat transfer coefficient and film effectiveness of a gas turbine blade

    E-Print Network [OSTI]

    Jiang, Huan Wanda

    1994-01-01T23:59:59.000Z

    Experiments were performed to study the effect of film hole location on local heat transfer coefficient and film effectiveness distributions of a turbine blade model with air (D.R. = 1.0) and C02 (D.R. = 1.52) film injection. Tests were performed...

  4. Deposition of hole-transport materials in solid-state dye-sensitized solar cells by doctor-blading

    E-Print Network [OSTI]

    McGehee, Michael

    Deposition of hole-transport materials in solid-state dye-sensitized solar cells by doctor Accepted 19 April 2010 Available online xxxx Keywords: Dye-sensitized solar cells Organic semiconductors)-9,90 -spirobifluorene) in solid-state dye-sensitized solar cells. Doctor-blading is a roll

  5. A Predictive Maintenance Policy Based on the Blade of Offshore Wind Wenjin Zhu, Troyes University of Technology

    E-Print Network [OSTI]

    McCalley, James D.

    A Predictive Maintenance Policy Based on the Blade of Offshore Wind Turbine Wenjin Zhu, Troyes onshore to offshore locations [1]. As offshore wind turbines are located at remote sites withlimited]. Operation and maintenance (O&M) costs of off-shore wind turbines contribute about 25-30% to the total energy

  6. DISCRETE ELEMENT MODELING OF BLADE–STRIKE FREQUENCY AND SURVIVAL OF FISH PASSING THROUGH HYDROKINETIC TURBINES

    SciTech Connect (OSTI)

    Romero Gomez, Pedro DJ; Richmond, Marshall C.

    2014-04-17T23:59:59.000Z

    Evaluating the consequences from blade-strike of fish on marine hydrokinetic (MHK) turbine blades is essential for incorporating environmental objectives into the integral optimization of machine performance. For instance, experience with conventional hydroelectric turbines has shown that innovative shaping of the blade and other machine components can lead to improved designs that generate more power without increased impacts to fish and other aquatic life. In this work, we used unsteady computational fluid dynamics (CFD) simulations of turbine flow and discrete element modeling (DEM) of particle motion to estimate the frequency and severity of collisions between a horizontal axis MHK tidal energy device and drifting aquatic organisms or debris. Two metrics are determined with the method: the strike frequency and survival rate estimate. To illustrate the procedure step-by-step, an exemplary case of a simple runner model was run and compared against a probabilistic model widely used for strike frequency evaluation. The results for the exemplary case showed a strong correlation between the two approaches. In the application case of the MHK turbine flow, turbulent flow was modeled using detached eddy simulation (DES) in conjunction with a full moving rotor at full scale. The CFD simulated power and thrust were satisfactorily comparable to experimental results conducted in a water tunnel on a reduced scaled (1:8.7) version of the turbine design. A cloud of DEM particles was injected into the domain to simulate fish or debris that were entrained into the turbine flow. The strike frequency was the ratio of the count of colliding particles to the crossing sample size. The fish length and approaching velocity were test conditions in the simulations of the MHK turbine. Comparisons showed that DEM-based frequencies tend to be greater than previous results from Lagrangian particles and probabilistic models, mostly because the DEM scheme accounts for both the geometric aspects of the passage event ---which the probabilistic method does--- as well as the fluid-particle interactions ---which the Lagrangian particle method does. The DEM-based survival rates were comparable to laboratory results for small fish but not for mid-size fish because of the considerably different turbine diameters. The modeling framework can be used for applications that aim at evaluating the biological performance of MHK turbine units during the design phase and to provide information to regulatory agencies needed for the environmental permitting process.

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

    SciTech Connect (OSTI)

    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

    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.

  8. Computing dynamic height from temperature profiles north of 30N in the Pacific Ocean

    E-Print Network [OSTI]

    O'Brien, Anthony

    1978-01-01T23:59:59.000Z

    COMPUTING DYNAMIC HEIGHT FROM TEMPERATURE PROFILES NORTH OP 30"N IN THE PACIFIC OCEAN A Thesis by ANTHONY O' BRIEN Submitted to the Graduate College of Texas A&M University in partial fullfillment of the requirement for the degree of 1f...ASTER OF SCIENCF. May 1978 Major Subject: Oceanography COMPUTING DYNA11IC HEIGHT FROM TE1IPERATURE PROFILES NORTH OF 30 N IN THE PACI1'IC OCEAN A thesis by ANTHONY O' BRIEN Approved as to style and content by: (Chairman of Com ittee) (Head of Depar nt...

  9. Minimum Entangling Power is Close to Its Maximum

    E-Print Network [OSTI]

    Jianxin Chen; Zhengfeng Ji; David W Kribs; Bei Zeng

    2012-10-04T23:59:59.000Z

    Given a quantum gate $U$ acting on a bipartite quantum system, its maximum (average, minimum) entangling power is the maximum (average, minimum) entanglement generation with respect to certain entanglement measure when the inputs are restricted to be product states. In this paper, we mainly focus on the 'weakest' one, i.e., the minimum entangling power, among all these entangling powers. We show that, by choosing von Neumann entropy of reduced density operator or Schmidt rank as entanglement measure, even the 'weakest' entangling power is generically very close to its maximal possible entanglement generation. In other words, maximum, average and minimum entangling powers are generically close. We then study minimum entangling power with respect to other Lipschitiz-continuous entanglement measures and generalize our results to multipartite quantum systems. As a straightforward application, a random quantum gate will almost surely be an intrinsically fault-tolerant entangling device that will always transform every low-entangled state to near-maximally entangled state.

  10. Laboratory Experiments on the Effects of Blade Strike from Hydrokinetic Energy Technologies on Larval and Juvenile Freshwater Fishes

    SciTech Connect (OSTI)

    Schweizer, Peter E [ORNL; Cada, Glenn F [ORNL; Bevelhimer, Mark S [ORNL

    2012-03-01T23:59:59.000Z

    There is considerable interest in the development of marine and hydrokinetic energy projects in rivers, estuaries, and coastal ocean waters of the United States. Hydrokinetic (HK) technologies convert the energy of moving water in river or tidal currents into electricity, without the impacts of dams and impoundments associated with conventional hydropower or the extraction and combustion of fossil fuels. The Federal Energy Regulatory Commission (FERC) maintains a database that displays the geographical distribution of proposed HK projects in inland and tidal waters (FERC 2012). As of March 2012, 77 preliminary permits had been issued to private developers to study HK projects in inland waters, the development of which would total over 8,000 MW. Most of these projects are proposed for the lower Mississippi River. In addition, the issuance of another 27 preliminary permits for HK projects in inland waters, and 3 preliminary permits for HK tidal projects (totaling over 3,100 MW) were under consideration by FERC. Although numerous HK designs are under development (see DOE 2009 for a description of the technologies and their potential environmental effects), the most commonly proposed current-based projects entail arrays of rotating devices, much like submerged wind turbines, that are positioned in the high-velocity (high energy) river channels. The many diverse HK designs imply a diversity of environmental impacts, but a potential impact common to most is the risk for blade strike to aquatic organisms. In conventional hydropower generation, research on fish passage through reaction turbines at low-head dams suggested that strike and mortality for small fish could be low. As a consequence of the large surface area to mass ratio of small fish, the drag forces in the boundary layer flow at the surface of a rotor blade may pull small fish around the leading edge of a rotor blade without making physical contact (Turnpenny 1998, Turnpenny et al. 2000). Although there is concern that small, fragile fish early life stages may be unable to avoid being struck by the blades of hydrokinetic turbines, we found no empirical data in the published literature that document survival of earliest life-stage fish in passage by rotor blades. In addition to blade strike, research on passage of fish through conventional hydropower turbines suggested that fish mortalities from passage through the rotor swept area could also occur due to shear stresses and pressure chances in the water column (Cada et al. 1997, Turnpenny 1998). However, for most of the proposed HK turbine designs the rotors are projected to operate a lower RPM (revolutions per minute) than observed from conventional reaction turbines; the associated shear stress and pressure changes are expected to be lower and pose a smaller threat to fish survival (DOE 2009). Only a limited number of studies have been conducted to examine the risk of blade strike from hydrokinetic technologies to fish (Turnpenny et al. 1992, Normandeau et al. 2009, Seitz et al. 2011, EPRI 2011); the survival of drifting or weakly swimming fish (especially early life stages) that encounter rotor blades from hydrokinetic (HK) devices is currently unknown. Our study addressed this knowledge gap by testing how fish larvae and juveniles encountered different blade profiles of hydrokinetic devices and how such encounters influenced survivorship. We carried out a laboratory study designed to improve our understanding of how fish larvae and juvenile fish may be affected by encounters with rotor blades from HK turbines in the water column of river and ocean currents. (For convenience, these early life stages will be referred to as young of the year, YOY). The experiments developed information needed to quantify the risk (both probability and consequences) of rotor-blade strike to YOY fish. In particular, this study attempted to determine whether YOY drifting in a high-velocity flow directly in the path of the blade leading edge will make contact with the rotor blade or will bypass the blade while entrained in the boundary l

  11. NGC2613, 3198, 6503, 7184: Case studies against `maximum' disks

    E-Print Network [OSTI]

    B. Fuchs

    1998-12-02T23:59:59.000Z

    Decompositions of the rotation curves of NGC2613, 3198, 6505, and 7184 are analysed. For these galaxies the radial velocity dispersions of the stars have been measured and their morphology is clearly discernible. If the parameters of the decompositions are chosen according to the `maximum' disk hypothesis, the Toomre Q stability parameter is systematically less than one and the multiplicities of the spiral arms as expected from density wave theory are inconsitent with the observed morphologies of the galaxies. The apparent Q<1 instability, in particular, is a strong argument against the `maximum' disk hypothesis.

  12. When are microcircuits well-modeled by maximum entropy methods?

    E-Print Network [OSTI]

    2010-07-20T23:59:59.000Z

    POSTER PRESENTATION Open Access When are microcircuits well-modeled by maximum entropy methods? Andrea K Barreiro1*, Eric T Shea-Brown1, Fred M Rieke2,3, Julijana Gjorgjieva4 From Nineteenth Annual Computational Neuroscience Meeting: CNS*2010 San... Antonio, TX, USA. 24-30 July 2010 Recent experiments in retina and cortex have demon- strated that pairwise maximum entropy (PME) methods can approximate observed spiking patterns to a high degree of accuracy [1,2]. In this paper we examine...

  13. Valence quark distributions of the proton from maximum entropy approach

    E-Print Network [OSTI]

    Rong Wang; Xurong Chen

    2014-10-14T23:59:59.000Z

    We present an attempt of maximum entropy principle to determine valence quark distributions in the proton at very low resolution scale $Q_0^2$. The initial three valence quark distributions are obtained with limited dynamical information from quark model and QCD theory. Valence quark distributions from this method are compared to the lepton deep inelastic scattering data, and the widely used CT10 and MSTW08 data sets. The obtained valence quark distributions are consistent with experimental observations and the latest global fits of PDFs. Maximum entropy method is expected to be particularly useful in the case where relatively little information from QCD calculation is given.

  14. Valence quark distributions of the proton from maximum entropy approach

    E-Print Network [OSTI]

    Wang, Rong

    2014-01-01T23:59:59.000Z

    We present an attempt of maximum entropy principle to determine valence quark distributions in the proton at very low resolution scale $Q_0^2$. The initial three valence quark distributions are obtained with limited dynamical information from quark model and QCD theory. Valence quark distributions from this method are compared to the lepton deep inelastic scattering data, and the widely used CT10 and MSTW08 data sets. The obtained valence quark distributions are consistent with experimental observations and the latest global fits of PDFs. Maximum entropy method is expected to be particularly useful in the case where relatively little information from QCD calculation is given.

  15. Assessing complexity by means of maximum entropy models

    E-Print Network [OSTI]

    Chliamovitch, Gregor; Velasquez, Lino

    2014-01-01T23:59:59.000Z

    We discuss a characterization of complexity based on successive approximations of the probability density describing a system by means of maximum entropy methods, thereby quantifying the respective role played by different orders of interaction. This characterization is applied on simple cellular automata in order to put it in perspective with the usual notion of complexity for such systems based on Wolfram classes. The overlap is shown to be good, but not perfect. This suggests that complexity in the sense of Wolfram emerges as an intermediate regime of maximum entropy-based complexity, but also gives insights regarding the role of initial conditions in complexity-related issues.

  16. 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

  17. Lower-Tropospheric Height Tendencies Associated with the Shearwise and Transverse Components of Quasigeostrophic Vertical Motion

    E-Print Network [OSTI]

    Williams, Justin

    of the separate lower-tropospheric height tendencies associated with the shearwise and transverse portions of QG- cluded surface cyclone are driven nearly equally by shearwise and transverse updrafts. 1. Introduction cyclones. He presented evidence that these two components of the QG vertical motion play different roles

  18. Neural Network Modeling of Structured Packing Height Equivalent to a Theoretical Plate

    E-Print Network [OSTI]

    Eldridge, R. Bruce

    -transfer ef- ficiency in structured packing. Column designers use the HETP to calculate the height of packing properties of the chemical system, and the operating conditions of the column. In a previous paper, Whaley et a detailed investigation of the parameters which impact the performance of structured packing in distillation

  19. On the study of wind energy at great heights using remote sensing techniques

    E-Print Network [OSTI]

    On the study of wind energy at great heights using remote sensing techniques Alfredo Pe~na1 by the wind energy industry due to the high sensitivity that the wind characteristics have on the performance Dong energy, Dong Energy, Kraftværksvej 53, DK-7000, Fredericia, Denmark e-mail: alfredo

  20. TOWARDS A CLOUD CEILOMETER NETWORK REPORTING MIXING LAYER HEIGHT Wiel M.F. Wauben

    E-Print Network [OSTI]

    Wauben, Wiel

    profiles if the aerosol concentrations are not too low. Since aerosol is well mixed in the atmospheric in the backscatter profile (cf. Wauben et al., 2006). Sometimes, medium and low clouds can also be missed or falsely1 TOWARDS A CLOUD CEILOMETER NETWORK REPORTING MIXING LAYER HEIGHT Wiel M.F. Wauben 1 , Marijn de

  1. Shear waves in colloidal crystals : II. Effects of finite height in cylindrical samples

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    to measure the relevant material constants such as compressibility [11] or shear modulus [2-4]. In the latter- tions of polycrystalline samples contained in glass cylinders (such as the tube T in Fig. 2) of height H are sharp provided that their frequencies are small compared to 1/i (condition (1)); for a given colloidal

  2. Annual Logging Symposium, June 16-20, 2012 SATURATION-HEIGHT AND INVASION CONSISTENT HYDRAULIC

    E-Print Network [OSTI]

    Torres-Verdín, Carlos

    clastic and carbonate reservoirs in multi-well contexts. It overcomes the limitation of the bulk volume on pore geometry, which relates to saturation-height modeling at a later stage in reservoir characterization. Additionally, pore geometry affects mud-filtrate invasion under over-balanced drilling conditions

  3. WAVE HEIGHTS IN A 4D OCEAN WAVE FIELD Paul C. Liu

    E-Print Network [OSTI]

    WAVE HEIGHTS IN A 4D OCEAN WAVE FIELD Paul C. Liu NOAA Great Lakes Environmental Research a preliminary examination and analysis of a small suite of 4-D wave data to explore what new insight century. We feel it is timely to encourage further 4-D ocean wave measurement and thereby facilitate fresh

  4. Master thesis Solar Energy Meteorology Comparison of different methods to estimate cloud height for solar

    E-Print Network [OSTI]

    Peinke, Joachim

    Master thesis ­ Solar Energy Meteorology Comparison of different methods to estimate cloud height: · Interest in meteorology and solar energy · Experiences with data handling and analysis · Good programming for solar irradiance calculations In order to derive incoming solar irradiance at the earths surface

  5. Effects of tree height on branch hydraulics, leaf structure and gas exchange in California redwoods

    E-Print Network [OSTI]

    Sillett, Stephen Charles

    with height in both species. Despite hydraulic adjustments, leaf mass per unit area (LMA) and leaf carbon sempervirens; Sequoiadendron gigan- teum; carbon isotopes; hydraulic conductivity; photosyn- thesis; stomatal becomes too great (Zimmermann 1983; Tyree & Sperry 1989). Air seeding occurs when an air bubble is pulled

  6. Effect of sampling height on the concentration of airborne fungal spores

    E-Print Network [OSTI]

    Levetin, Estelle

    and possible sources of air pollution.8 In addition, it is high enough to avoid vandalism and bothering aeroallergens. Airborne fungal spores are commonly collected from the outdoor air at the rooftop level of high respiration level (1.5 m above the ground) and at roof level (12 m height). Methods: Air samples were

  7. Alcator C-Mod soft X-ray pulse height analysis system

    E-Print Network [OSTI]

    Gamboa, Eliseo (Eliseo J.)

    2007-01-01T23:59:59.000Z

    A pulse height analysis (PHA) system has been installed on the Alcator C-Mod magnetic confinement fusion experiment. The PHA utilizes a Si(Li) detector to measure soft X-rays in the 1-30 keV range with an energy resolution ...

  8. Department of Mechanical Engineering Spring 2011 General Motors 2 Variable Height Vehicle Air Dam

    E-Print Network [OSTI]

    Demirel, Melik C.

    Vehicle Air Dam Overview The fundamental issue with fixed air dams is the bottom edge of the dam needs to be high enough to meet defined vehicle ground clearance and front approach angle criteria. Air dams must a solution to this problem by designing an variable height vehicle air dam. Objectives Our mission

  9. Maximum stellar mass versus cluster membership number revisited

    E-Print Network [OSTI]

    Th. Maschberger; C. J. Clarke

    2008-09-05T23:59:59.000Z

    We have made a new compilation of observations of maximum stellar mass versus cluster membership number from the literature, which we analyse for consistency with the predictions of a simple random drawing hypothesis for stellar mass selection in clusters. Previously, Weidner and Kroupa have suggested that the maximum stellar mass is lower, in low mass clusters, than would be expected on the basis of random drawing, and have pointed out that this could have important implications for steepening the integrated initial mass function of the Galaxy (the IGIMF) at high masses. Our compilation demonstrates how the observed distribution in the plane of maximum stellar mass versus membership number is affected by the method of target selection; in particular, rather low n clusters with large maximum stellar masses are abundant in observational datasets that specifically seek clusters in the environs of high mass stars. Although we do not consider our compilation to be either complete or unbiased, we discuss the method by which such data should be statistically analysed. Our very provisional conclusion is that the data is not indicating any striking deviation from the expectations of random drawing.

  10. Maximum likelihood estimation of the equity Efstathios Avdis

    E-Print Network [OSTI]

    Kahana, Michael J.

    premium is usually estimated by taking the sample mean of stock returns and subtracting a measure the expected return on the aggregate stock market less the government bill rate, is of central importance an alternative esti- mator, based on maximum likelihood, that takes into account informa- tion contained

  11. STATE OF CALIFORNIA MAXIMUM RATED TOTAL COOLING CAPACITY

    E-Print Network [OSTI]

    /09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-27-HERS Maximum Rated Total Cooling Capacity of the installed system (Btu/hr) 3b Sum of the ARI Rated Total Cooling Capacities of multiple systems installed Cooling Capacities of the installed cooling systems must be calculated and entered in row 3b. 4a MRTCC

  12. Maximum power tracking control scheme for wind generator systems

    E-Print Network [OSTI]

    Mena Lopez, Hugo Eduardo

    2008-10-10T23:59:59.000Z

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  13. Maximum power tracking control scheme for wind generator systems

    E-Print Network [OSTI]

    Mena, Hugo Eduardo

    2009-05-15T23:59:59.000Z

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  14. annual maximum water: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    annual maximum water First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 ORIGINAL PAPER The distribution of...

  15. BRANCH-CUT-AND-PROPAGATE FOR THE MAXIMUM k ...

    E-Print Network [OSTI]

    2011-03-16T23:59:59.000Z

    maximum k-colorable subgraph problem consists of selecting a k-color- able induced subgraph of ..... a symmetric subgroup Sp of Aut(G) acts on Vp for all p ? [s]. Let Vp = {vp. 1,...,vp qp. } ...... [9] J. Crawford, M. Ginsberg, E. Luks, and A. Roy.

  16. Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint

    E-Print Network [OSTI]

    Greenberg, Albert

    Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint Zhe Wang Electrical--In this paper, we develop efficient algorithm to obtain the optimal energy schedule for fading channel with energy harvesting. We assume that the side information of both the channel states and energy harvesting

  17. What is a Hurricane? Tropical system with maximum sustained

    E-Print Network [OSTI]

    Meyers, Steven D.

    Andrew-Category 4· Category 4 Hurricane - Winds 131-155 mph. Wall failures in homes and complete roofHurricane 101 #12;What is a Hurricane? · Tropical system with maximum sustained surface wind of 74 mph or greater. A hurricane is the worst and the strongest of all tropical systems. · Also known

  18. Individual Module Maximum Power Point Tracking for Thermoelectric Generator Systems

    E-Print Network [OSTI]

    Schaltz, Erik

    of Thermo Electric Generator (TEG) systems a power converter is often inserted between the TEG system that the TEG system produces the maximum power. However, if the conditions, e.g. temperature, health, age, etc find the best compromise of all modules. In order to increase the power production of the TEG system

  19. Efficiency Improvement of an IPMSM using Maximum Efficiency Operating Strategy

    E-Print Network [OSTI]

    Paderborn, Universität

    Efficiency Improvement of an IPMSM using Maximum Efficiency Operating Strategy Daniel Pohlenz. These are characterized by high efficiency and high torque as well as power density. The generation of reference currents that the MTPC method deviates considerably from the best efficiency under certain boundary conditions. The use

  20. Maximum power tracking control scheme for wind generator systems 

    E-Print Network [OSTI]

    Mena, Hugo Eduardo

    2009-05-15T23:59:59.000Z

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...