National Library of Energy BETA

Sample records for maximum blade height

  1. On the geometrical place formed by the maximum heights of projectile motion with air resistance

    E-Print Network [OSTI]

    Hernández-Saldaña, H

    2010-01-01

    We present an analysis on the geometrical place formed by the set of maxima of the orbits of a projectile launched in a media with linear drag. Such a place is written in term of the Lambert W function in polar coordinates, confirming the special role played by this function in the problem. In order to characterize it, a study of the curvature is presented in two parameterizations, in terms of the launching angle and in the polar one. The angles of maximum curvature are compared with other important angles in the projectile problem.

  2. Ceramic blade attachment system

    DOE Patents [OSTI]

    Boyd, G.L.

    1995-04-11

    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)

    1995-01-01

    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. Sandia Energy - Radar Friendly Blades

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

    Radar Friendly Blades Home Stationary Power Energy Conversion Efficiency Wind Energy Siting and Barrier Mitigation Radar Friendly Blades Radar Friendly BladesTara...

  5. Blade Model Galerkin Approach

    E-Print Network [OSTI]

    Patil, Mayuresh

    and Control Design of Active Helicopter Blades Matthias Althoff1 Mayuresh Patil2 Johannes Traugott1 1 design and simulation of smart helicopter blades Past Work (Traugott and Patil, SDM 2005) ChangedMotivation Blade Model Galerkin Approach Solution and Results Concluding Remarks Nonlinear Modeling

  6. OF CARBON FIBERS TURBINE BLADE

    E-Print Network [OSTI]

    THE USE IN WIND DESIGN: OF CARBON FIBERS TURBINE BLADE A SERI-8BLADE EXAMPLE Cheng Printed March 2000 The Use of Carbon Fibers in Wind Turbine Blade Design: a SERI-8 Blade Example Cheng represent different volumes of carbon fibers in the blade, were also studied for two design options

  7. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, J.E.

    1995-07-11

    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.

  8. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, James E. (Maitland, FL)

    1995-01-01

    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.

  9. An experimental study of heat transfer in the rectangular coolant passages of a gas turbine rotor blade 

    E-Print Network [OSTI]

    Uddin, Mohammed Jalal

    2000-01-01

    Modern gas turbines have high inlet temperatures to harness maximum power output, which causes different components to experience severe thermal stresses and fatigue. To achieve turbine blade durability goals, the blades are cooled with air...

  10. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, James E. (Maitland, FL)

    1995-01-01

    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. Ceramic blade attachment system

    DOE Patents [OSTI]

    Shaffer, J.E.

    1995-01-10

    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.

  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, Gary L. (Alpine, CA)

    1994-01-01

    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.

  14. Ceramic blade attachment system

    DOE Patents [OSTI]

    Boyd, G.L.

    1994-12-13

    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.

  15. Blade Testing Trends (Presentation)

    SciTech Connect (OSTI)

    Desmond, M.

    2014-08-01

    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. Sandia Energy - Rotor Blade Sensors and Instrumentation

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

    Blade Sensors and Instrumentation Home Stationary Power Energy Conversion Efficiency Wind Energy Rotor Innovation Rotor Blade Sensors and Instrumentation Rotor Blade Sensors and...

  17. Ceramic blade attachment system

    DOE Patents [OSTI]

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

    1996-12-03

    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.

  18. Ceramic blade attachment system

    DOE Patents [OSTI]

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

    1996-01-01

    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.

  19. Fluid blade disablement tool

    DOE Patents [OSTI]

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

    2012-01-10

    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.

  20. Cooled snubber structure for turbine blades

    DOE Patents [OSTI]

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

    2014-04-01

    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.

  1. Collegiate Wind Competition Turbines go Blade-to-Blade in Wind...

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

    Collegiate Wind Competition Turbines go Blade-to-Blade in Wind Tunnel Tests at WINDPOWER Collegiate Wind Competition Turbines go Blade-to-Blade in Wind Tunnel Tests at WINDPOWER...

  2. Collegiate Wind Competition Turbines go Blade-to-Blade in Wind...

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

    Turbines go Blade-to-Blade in Wind Tunnel Tests at WINDPOWER Collegiate Wind Competition Turbines go Blade-to-Blade in Wind Tunnel Tests at WINDPOWER March 28, 2014 - 5:11pm...

  3. Snubber assembly for turbine blades

    DOE Patents [OSTI]

    Marra, John J

    2013-09-03

    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.

  4. Ceramic blade with tip seal

    DOE Patents [OSTI]

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

    1997-08-05

    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.

  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

    2014-04-30

    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. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo,AltFuelVehicle2 Jump to: navigation, searchContDiv JumpTechDsc JumpLabVelocity at Wave

  7. Multiple piece turbine blade

    DOE Patents [OSTI]

    Kimmel, Keith D (Jupiter, FL)

    2012-05-29

    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.

  8. Turbine blade cooling

    DOE Patents [OSTI]

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

    1999-07-20

    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.

  9. Optical Blade Position Tracking System Test

    SciTech Connect (OSTI)

    Fingersh, L. J.

    2006-01-01

    The Optical Blade Position Tracking System Test measures the blade deflection along the span of the blade using simple off-the-shelf infrared security cameras along with blade-mounted retro-reflective tape and video image processing hardware and software to obtain these measurements.

  10. Wooden wind turbine blade manufacturing process

    DOE Patents [OSTI]

    Coleman, Clint (Warren, VT)

    1986-01-01

    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.

  11. Apparatus for loading a band saw blade

    DOE Patents [OSTI]

    Reeves, S.R.

    1990-03-20

    A band saw blade is loaded between pairs of guide wheels upon tensioning the blade by guiding the blade between pairs of spaced guide plates which define converging slots that converge toward the guide wheels. The approach is particularly useful in loading blades on underwater band saw machines used to cut radioactive materials. 2 figs.

  12. Apparatus for loading a band saw blade

    DOE Patents [OSTI]

    Reeves, Steven R. (49 Williams Ave., West Valley, NY 14171)

    1990-01-01

    A band saw blade is loaded between pairs of guide wheels upon tensioning the blade by guiding the blade between pairs of spaced guide plates which define converging slots that converge toward the guide wheels. The approach is particularly useful in loading blades on underwater band saw machines used to cut radioactive materials.

  13. 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)

    1997-01-01

    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).

  14. Sandia Energy - Blade Reliability Collaborative

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

    environment, creates a challenge for blade designers and manufacturers, as well as wind-farm operators. In many cases, failures in the field can be traced back to the...

  15. Aero-Structural Design Investigations for Biplane Wind Turbine Blades

    E-Print Network [OSTI]

    Roth-Johnson, Perry

    2014-01-01

    Blade designs are defined by a set of cross-sectionclass of blade designs . . . . . . . . . . . . .Artisticand Structural Blade and Wing Design,” 2011. [35] R. E. Wirz

  16. 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...

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

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

    multimegawatt wind turbine blade flap fatigue test. Addthis Related Articles DOE's New Large Blade Test Facility in Massachusetts Completes First Commercial Blade Tests...

  18. Aero-Structural Design Investigations for Biplane Wind Turbine Blades

    E-Print Network [OSTI]

    Roth-Johnson, Perry

    2014-01-01

    Turbine Blades,” in AWEA Windpower, (Atlanta, GA), pp. 1–22,turbine blades,” AWEA Windpower, Atlanta, GA, (presentation)

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

    SciTech Connect (OSTI)

    Hughes, S.

    2010-07-20

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

  20. Probabilistic analysis of turbine blade durability

    E-Print Network [OSTI]

    Kountras, Apostolos, 1970-

    2004-01-01

    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. A Simplified Morphing Blade for Horizontal Axis Wind Turbines

    E-Print Network [OSTI]

    Recanati, Catherine

    by adjusting the twist of the blade's root and tip. To evaluate the performance of wind turbine blades of the NREL Phase VI wind turbine is taken as a reference blade and has a fixed pitch. The optimization was evalu- ated for three types of blade, namely, morphing blade, blade with pitch control and fixed pitch

  2. Blade for a gas turbine

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-10-26

    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.

  3. The Independence Heights House

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

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE- Non-ResidentialAlliantPGE andOffice -EnergyEnergy |Heights House Prairie

  4. Turbine blade tip flow discouragers

    DOE Patents [OSTI]

    Bunker, Ronald Scott (Niskayuna, NY)

    2000-01-01

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

  5. Articulated limiter blade for a tokamak fusion reactor

    DOE Patents [OSTI]

    Doll, D.W.

    1982-10-21

    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.

  6. Articulated limiter blade for a tokamak fusion reactor

    DOE Patents [OSTI]

    Doll, David W. (San Diego, CA)

    1985-01-01

    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.

  7. Turbine blade tip gap reduction system

    DOE Patents [OSTI]

    Diakunchak, Ihor S.

    2012-09-11

    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.

  8. Rotor blades for turbine engines

    SciTech Connect (OSTI)

    Piersall, Matthew R; Potter, Brian D

    2013-02-12

    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.

  9. Load attenuating passively adaptive wind turbine blade

    DOE Patents [OSTI]

    Veers, Paul S.; Lobitz, Donald W.

    2003-01-07

    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.

  10. Load attenuating passively adaptive wind turbine blade

    DOE Patents [OSTI]

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

    2003-01-01

    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.

  11. Cooling arrangement for a tapered turbine blade

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-07-27

    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.

  12. 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

  13. Sandia Energy - Blade Materials and Substructures Testing

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

    testing is used to characterize new composite materials to obtain design properties. Wind turbine blades are subjected to a higher number of complex loading cycles not...

  14. Adaptor assembly for coupling turbine blades to rotor disks

    DOE Patents [OSTI]

    Garcia-Crespo, Andres Jose; Delvaux, John McConnell

    2014-09-23

    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.

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

    E-Print Network [OSTI]

    Huang, Ivy

    2011-01-01

    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. Multiple piece turbine rotor blade

    DOE Patents [OSTI]

    Jones, Russell B; Fedock, John A

    2013-05-21

    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.

  17. Sandia Energy - Radar Friendly Blades

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II)Geothermal Energy &WaterNewPhotoionizationPowerRadar Friendly Blades

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

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

    also inform how blade inspections are conducted at manufacturing facilities and wind farms, thereby improving maintenance and repair procedures for wind turbine blades. SNL is...

  19. Upcoming Funding Opportunity to Develop Larger Wind Turbine Blades...

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

    Upcoming Funding Opportunity to Develop Larger Wind Turbine Blades Upcoming Funding Opportunity to Develop Larger Wind Turbine Blades February 20, 2015 - 4:55pm Addthis On February...

  20. Modeling and Driving Piezoelectric Resonant Blade Elements

    E-Print Network [OSTI]

    Modeling and Driving Piezoelectric Resonant Blade Elements Sam Ben-Yaakov* and Natan Krihely Power@ee.bgu.ac.il ; Website: http://www.ee.bgu.ac.il/~pel Abstract-- Piezoelectric Resonant Blade elements (PRB) are useful in applications such as light choppers, laser beam scanners, fans and others. Three methods are proposed

  1. Massachusetts Large Blade Test Facility Final Report

    SciTech Connect (OSTI)

    Rahul Yarala; Rob Priore

    2011-09-02

    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.

  2. Turbine blade damping device with controlled loading

    DOE Patents [OSTI]

    Marra, John J.

    2015-09-29

    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. Turbine blade damping device with controlled loading

    DOE Patents [OSTI]

    Marra, John J

    2013-09-24

    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.

  4. Advanced Blade Manufacturing Project - Final Report

    SciTech Connect (OSTI)

    POORE, ROBERT Z.

    1999-08-01

    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.

  5. 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 material. A critical task of such synthesis in turbine blade design is an effective design method approach for turbine blade design, which ties B-spline representation of a turbine blade to a physics

  6. NONLINEAR DYNAMICS AND CONTROL OF INTEGRALLY ACTUATED HELICOPTER BLADES

    E-Print Network [OSTI]

    Patil, Mayuresh

    Helicopter Blades, Nonlinear Finite Elements, Intrinsic Formulation, Control Design Abstract: A set characteristics of the helicopter. The design and development of new `smart' blades requires accurate modeling of the active blade, coupled with appropriate control design methodology. Active blade models can be developed

  7. Method of making a wooden wind turbine blade

    DOE Patents [OSTI]

    Coleman, Clint (Warren, VT)

    1984-01-01

    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. Method of making a wooden wind turbine blade

    DOE Patents [OSTI]

    Coleman, C.

    1984-08-14

    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.

  9. 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

  10. Variable diameter wind turbine rotor blades

    DOE Patents [OSTI]

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

    2005-12-06

    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.

  11. Pin and roller attachment system for ceramic blades

    DOE Patents [OSTI]

    Shaffer, J.E.

    1995-07-25

    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.

  12. Pin and roller attachment system for ceramic blades

    DOE Patents [OSTI]

    Shaffer, James E. (Maitland, FL)

    1995-01-01

    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.

  13. Robust design and tolerancing of compressor blades

    E-Print Network [OSTI]

    Dow, Eric Alexander

    2015-01-01

    Variations in the geometry of compressor blades can be introduced by variability in the manufacturing process or by in-service erosion. Recent research efforts have focused on characterizing the impacts of this geometric ...

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

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

    Awards 1.8 Million to Develop Wind Turbine Blades to Access Better Wind Resources and Reduce Costs President Obama Awards 2.3 Billion for New Clean-Tech Manufacturing Jobs...

  15. 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/.

  16. High efficiency turbine blade coatings.

    SciTech Connect (OSTI)

    Youchison, Dennis L.; Gallis, Michail A.

    2014-06-01

    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.

  17. Forging of compressor blades: Temperature and ram velocity effects

    SciTech Connect (OSTI)

    Saigal, A.; Zhen, K.; Chan, T.S.

    1995-07-01

    Forging is one of the most widely used manufacturing process for making high-strength, structurally integrated, impact and creep-resistant Ti-6Al-4V compressor blades for jet engines. In addition, in modern metal forming technology, finite element analysis method and computer modeling are being extensively employed for initial evaluation and optimization of various processes, including forging. In this study, DEFORM, a rigid viscoplastic two-dimensional finite element code was used to study the effects of initial die temperature and initial ram velocity on the forging process. For a given billet, die temperature and ram velocity influence the strain rate, temperature distribution,and thus the flow stress of the material. The die temperature and the ram velocity were varied over the range 300 to 700 F and 15--25 in./sec, respectively, to estimate the maximum forging load and the total energy required to forge compressor blades. The ram velocity was assumed to vary linearly as a function of stroke. Based on the analysis,it was found the increasing the die temperature from 300 to 700 F decreases the forging loads by 19.9 percent and increases the average temperature of the workpiece by 43 F. Similarly, increasing the initial ram velocity from 15 to 25 in./sec decreases the forging loads by 25.2 percent and increases the average temperature of the workpiece by 36 F. The nodal temperature distribution is bimodal in each case. The forging energy required to forge the blades is approximately 18 kips *in./in.

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

    SciTech Connect (OSTI)

    Bir, G. S.

    2010-09-01

    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.

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

    SciTech Connect (OSTI)

    Griffith, Daniel Todd

    2013-02-01

    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.

  20. Height fluctuations in interacting dimers

    E-Print Network [OSTI]

    Alessandro Giuliani; Vieri Mastropietro; Fabio Lucio Toninelli

    2015-05-05

    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.

  1. 3X-100 blade field test.

    SciTech Connect (OSTI)

    Zayas, Jose R.; Johnson, Wesley D.

    2008-03-01

    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.

  2. 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)

    2008-04-01

    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.

  3. Aero-Structural Design Investigations for Biplane Wind Turbine Blades

    E-Print Network [OSTI]

    Roth-Johnson, Perry

    2014-01-01

    14] 4C Offshore, “Offshore Wind Turbine: S7.0-171, Sam- sungblade for a 7-MW offshore wind turbine [8], and blades arefor a 6-megawatt offshore wind turbine [79, 80]. Blades are

  4. Simultaneous Robust Design and Tolerancing of Compressor Blades

    E-Print Network [OSTI]

    Wang, Qiqi

    The manufacturing processes used to create compressor blades inevitably introduce geometric variability to the blade surface. In addition to increasing the performance variability, it has been observed that introducing ...

  5. Methods and apparatus for rotor blade ice detection

    DOE Patents [OSTI]

    LeMieux, David Lawrence

    2006-08-08

    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.

  6. Wind blade spar cap and method of making

    DOE Patents [OSTI]

    Mohamed, Mansour H. (Raleigh, NC)

    2008-05-27

    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.

  7. Experimental investigation of film cooling effectiveness on gas turbine blades 

    E-Print Network [OSTI]

    Gao, Zhihong

    2009-05-15

    high temperature and high pressure blades as an active cooling scheme. In this study, the film cooling effectiveness in different regions of gas turbine blades was investigated with various film hole/slot configurations and mainstream flow conditions...

  8. Vertical axis wind turbine with continuous blade angle adjustment

    E-Print Network [OSTI]

    Weiss, Samuel Bruce

    2010-01-01

    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 ...

  9. Business expansion and lean transformation for helicopter blade shop

    E-Print Network [OSTI]

    Bar, S. Neil (Saumen Neil)

    2006-01-01

    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 ...

  10. Reduced Order Structural Modeling of Wind Turbine Blades 

    E-Print Network [OSTI]

    Jonnalagadda, Yellavenkatasunil

    2011-10-21

    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...

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

    E-Print Network [OSTI]

    Choi, Jungho

    2005-02-17

    and internal model of a gas turbine blade. It was also used to determine the film effectiveness on the trailing edge. For the internal model, Reynolds numbers based on the hydraulic diameter of iv the exit slot and exit velocity were 5,000, 10,000, 20...-1 AN EXPERIMENTAL INVESTIGATION OF TURBINE BLADE HEAT TRANSFER AND TURBINE BLADE TRAILING EDGE COOLING A Dissertation by JUNGHO CHOI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements...

  12. Dual-Axis Resonance Testing of Wind Turbine Blades

    Energy Innovation Portal (Marketing Summaries) [EERE]

    2014-07-28

    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...

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

    SciTech Connect (OSTI)

    J.L. Rovey K. Chandrashekhara

    2012-09-21

    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.

  14. High-Resolution Simulations of Parallel BladeVortex Interactions

    E-Print Network [OSTI]

    Alonso, Juan J.

    to that encountered in the simulation of realistic helicopter blade­vortex interaction, but the computational costs aeroacoustics rotor tests [2,3]. These tests were performed on a Mach-scaled Bo-105 rotor and the blade loadsHigh-Resolution Simulations of Parallel Blade­Vortex Interactions Alasdair Thom University

  15. Nonlinear Modeling and Control Design of Active Helicopter Blades

    E-Print Network [OSTI]

    Patil, Mayuresh

    Nonlinear Modeling and Control Design of Active Helicopter Blades Matthias Althoff , Mayuresh J dynamic solution and control design of active helicopter blades. Following are the significant new reduction technique is used to derive a low-order, high fidelity nonlinear blade model for control design

  16. Nonlinear Dynamics and Control of Integrally Actuated Helicopter Blades

    E-Print Network [OSTI]

    Patil, Mayuresh

    - bility of the blade is discussed under the influence of rigid body motion. In a final step, the design control design methodology. Active blade models can be developed based on pure three dimensional finite potential of a given active blade configuration and to design an optimal MIMO controller providing

  17. Wavelength modulation spectroscopy using novel mechanical light chopper blade designs

    E-Print Network [OSTI]

    Ghosh, Sandip

    Wavelength modulation spectroscopy using novel mechanical light chopper blade designs Jayeeta 23 May 2005; published online 21 July 2005 We describe two mechanical light chopper blade designs wavelength for positive grating orders. Our two designs, the alternating double-slot blade and the vertical

  18. 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 reversed tension-compression. ­ Data used in blade design can be of uncertainData used in blade design can (Power Law Most Common)q ( ) #12;Statistical Confidence Limit Representation, Power Law and Three-ParameterPower

  19. 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

  20. Method for maintaining a cutting blade centered in a kerf

    DOE Patents [OSTI]

    Blaedel, Kenneth L. (Dublin, CA); Davis, Pete J. (Pleasanton, CA); Landram, Charles S. (Livermore, CA)

    2002-01-01

    A saw having a self-pumped hydrodynamic blade guide or bearing for retaining the saw blade in a centered position in the saw kerf (width of cut made by the saw). The hydrodynamic blade guide or bearing utilizes pockets or grooves incorporated into the sides of the blade. The saw kerf in the workpiece provides the guide or bearing stator surface. Both sides of the blade entrain cutting fluid as the blade enters the kerf in the workpiece, and the trapped fluid provides pressure between the blade and the workpiece as an inverse function of the gap between the blade surface and the workpiece surface. If the blade wanders from the center of the kerf, then one gap will increase and one gap will decrease and the consequent pressure difference between the two sides of the blade will cause the blade to re-center itself in the kerf. Saws using the hydrodynamic blade guide or bearing have particular application in slicing slabs from boules of single crystal materials, for example, as well as for cutting other difficult to saw materials such as ceramics, glass, and brittle composite materials.

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

    SciTech Connect (OSTI)

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

    2013-04-01

    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.

  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

    2013-07-16

    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. Turbine blade squealer tip rail with fence members

    DOE Patents [OSTI]

    Little, David A

    2012-11-20

    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.

  4. Improved stud configurations for attaching laminated wood wind turbine blades

    SciTech Connect (OSTI)

    Faddoul, J.R.

    1985-09-01

    In order to improve joint strength for bonded studs in laminated wood structures (wind turbine blades) a series of designs was developed and tested. Each design systematically varied a parameter which was expected to have a significant effect on performance. The structural capability of each design was established based on tension-tension fatigue tests, and it was found that a stud with a concave tapered carrot design, bonded in place with an epoxy thickened with chopped carbon fiber, was the most effective design. Further improvements in joint performance could be made by augmenting the laminated wood with thin plies of carbon cloth (10 percent thickness buildup) in the area of the stud. Two designs were selected for further testing, which demonstrated that joint strengths approaching the membrane wood strength could be achieved. For a 3- by 3-inch wood block, an ultimate load exceeding 100,000 lbs could be introduced through a single bonded stud. For the same type of specimen in cyclic tension at an R-ratio of 0.1, the bonded studs were projected to have a fatigue life of 4 x 10/sup 8/ cycles at maximum loads of 30,000 lbs. For reversed axial fatigue, a reduction of 25 percent from these numbers was shown to be appropriate. These values represent an improvement of 100 percent over the stud designs used previously for laminated wood wind turbine blades. However, temperatures of 100/sup 0/F with humidity at 100 percent in certain cases caused a loss of ultimate load capability approaching 35 percent and a loss of fatigue capacity approaching 50 percent. While this result may have been specimen-related, additional testing or a change in the epoxy resin system should be considered before using the bonded stud designs in hot, humid environments.

  5. Turbine blade with contoured chamfered squealer tip

    DOE Patents [OSTI]

    Lee, Ching-Pang

    2014-12-30

    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. Tip cap for a turbine rotor blade

    DOE Patents [OSTI]

    Kimmel, Keith D

    2014-03-25

    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.

  7. 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.

    1989-11-01

    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.

  8. Turbine blade with tuned damping structure

    DOE Patents [OSTI]

    Campbell, Christian X.; Messmann, Stephen J.

    2015-09-01

    A turbine blade is provided comprising: a root; an airfoil comprising an external wall extending radially from the root and having a radially outermost portion; and a damping structure. The external wall may comprise first and second side walls joined together to define an inner cavity of the airfoil. The damping structure may be positioned within the airfoil inner cavity and coupled to the airfoil so as to define a tuned mass damper.

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

    SciTech Connect (OSTI)

    Ashwill, Thomas D.

    2010-02-01

    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. 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)

    2011-08-09

    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).

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

    DOE Patents [OSTI]

    Fleming, James G.; Sniegowski, Jeffry J.; Montague, Stephen

    2003-09-09

    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).

  12. 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 ...

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

    E-Print Network [OSTI]

    Taylor, Sym 1978-

    2012-12-07

    In recent times, communities and structures along the Gulf of Mexico have experienced the destructive and devastating impact of hurricane surges and waves. While the impacts of surges have been studied, there exists a need for (1) the understanding...

  14. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo,AltFuelVehicle2 Jump to: navigation, searchContDiv JumpTechDsc JumpLabVelocity at Wave

  15. Turbine blade having a constant thickness airfoil skin

    DOE Patents [OSTI]

    Marra, John J

    2012-10-23

    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.

  16. Sandia Energy - Senator Bingaman Tells Sandia Wind Turbine Blade...

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

    turbine design, blade and rotor testing, manufacturing and inspection, distributed wind technology, and water power. Bingaman said a diversity of U.S. energy sources at a...

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

    SciTech Connect (OSTI)

    Griffith, Daniel Todd

    2010-11-01

    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.

  18. PPG and MAG Team Up for Turbine Blade Research

    Broader source: Energy.gov [DOE]

    Two companies work together to move forward in the industry, researching materials and processes that could lead to stronger, more reliable wind blades.

  19. Improved blade profile loss and deviation angle models for advanced transonic compressor bladings. Part 2: A model for supersonic flow

    SciTech Connect (OSTI)

    Koenig, W.M.; Hennecke, D.K.; Fottner, L.

    1996-01-01

    New blading concepts as used in modern transonic axial-flow compressors require improved loss and deviation angle correlations. The new model presented in this paper incorporates several elements and treats blade-row flows having subsonic and supersonic inlet conditions separately. The second part of the present report focuses on the extension of a well-known correlation for cascade losses at supersonic inlet flows. It was originally established for DCA bladings and is now modified to reflect the flow situation in blade rows having low-cambered, arbitrarily designed blades including precompression blades. Finally, the steady loss increase from subsonic to supersonic inlet-flow velocities demonstrates the matched performance of the different correlations of the new model.

  20. 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.

  1. Raman lidar/AERI PBL Height Product

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

    Ferrare, Richard

    2012-12-14

    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.

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

    E-Print Network [OSTI]

    Sidwell, Carroll Vincent, 1972-

    2004-01-01

    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 ...

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

    SciTech Connect (OSTI)

    Griffith, Daniel; Richards, Phillip William

    2014-09-01

    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.

  4. Multiple piece turbine blade/vane

    DOE Patents [OSTI]

    Kimmel, Keith D

    2013-02-05

    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.

  5. Maximum-likelihood

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on dark matter By Sarah Schlieder *8MatthewMaximum-likelihood fitting

  6. 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

  7. Vibration and Structural Response of Hybrid Wind Turbine Blades 

    E-Print Network [OSTI]

    Nanami, Norimichi

    2011-02-22

    to the square of the blade length and the cube of the wind speed, wind turbine size has grown rapidly in the last two decades to match the increase in power output. As the blade length increases, so does its weight opening up design possibilities to introduce...

  8. Testing a Prototype Blade Antenna at the LWDA Site

    E-Print Network [OSTI]

    Ellingson, Steven W.

    1 Testing a Prototype Blade Antenna at the LWDA Site Nagini Paravastu, William Erickson, Ylva summarizes the testing done on a prototype LWDA blade antenna at the VLA on August 30, 2005 ­ September 1, 2005. As the LWDA project transitions from the planning and design phases to the construction phase

  9. Disaggregated Memory for Expansion and Sharing in Blade Servers

    E-Print Network [OSTI]

    Wenisch, Thomas F.

    1 Disaggregated Memory for Expansion and Sharing in Blade Servers Kevin Lim*, Jichuan Chang-memory co-location on a single system and details the design of a new general-purpose architectural building block--a memory blade--that allows memory to be "disaggregated" across a system ensemble. This remote

  10. Testing a Prototype Blade Antenna at the LWDA-1 Site

    E-Print Network [OSTI]

    Ellingson, Steven W.

    1 Testing a Prototype Blade Antenna at the LWDA-1 Site Nagini Paravastu, William Erickson, Ylva the testing done on a prototype LWDA blade antenna at the VLA on August 30, 2005 ­ September 1, 2005. As the LWDA project transitions from the planning and design phases to the construction phase, field

  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 for flapwise loads on three horizontal axis wind tur­ bines(HAWTs). In the case of two of these turbines

  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. TECHNICALADVANCES IN EPOXY TECHNOLOGY FOR WIND TURBINE BLADE COMPOSITE FABRICATION

    E-Print Network [OSTI]

    environmental factors such as temperature cycling, humidity and bird strikes. Failures of these composite blades in wind turbine blades and thereby provide solutions to address these failures by leveraging key novel, will generate the decrease in cost per kWh which the industry needs to be competitive with other sources

  14. Volumetric Geometry Reconstruction of Turbine Blades for Aircraft Engines

    E-Print Network [OSTI]

    Jüttler, Bert

    Volumetric Geometry Reconstruction of Turbine Blades for Aircraft Engines David Großmann1 and Bert features throughout the process. Keywords: volumetric geometry reconstruction, turbine blades, trivari- ate. The volumetric B-spline parametrization ­ which is discussed in the present paper ­ enables us to explore new

  15. Turbine blades and systems with forward blowing slots

    DOE Patents [OSTI]

    Zuteck, Michael D.; Zalusky, Leigh; Lees, Paul

    2015-09-15

    A blade for use in a wind turbine comprises a pressure side and suction side meeting at a trailing edge and leading edge. The pressure side and suction side provide lift to the turbine blade upon the flow of air from the leading edge to the trailing edge and over the pressure side and suction side. The blade includes one or more openings at the suction side, in some cases between the leading edge and the trailing edge. The one or more openings are configured to provide a pressurized fluid towards the leading edge of the blade, in some cases at an angle between about 0.degree. and 70.degree. with respect to an axis oriented from a centerline of the blade toward the leading edge.

  16. Wind turbine blade testing system using base excitation

    DOE Patents [OSTI]

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

    2014-03-25

    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).

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

    SciTech Connect (OSTI)

    Resor, Brian Ray

    2013-04-01

    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.

  18. Morphological features of tweeks and nighttime D region ionosphere at tweek reflection height from the observations

    E-Print Network [OSTI]

    % during summer season and about 19% and 18% occurrences during equinox and winter seasons. Maximum to that during equinox and winter. Seasonally, tweek (ionospheric) reflection height in the premidnight (18:00-00:00 LT) during winter is less as compared to that during equinox and summer. Annual (seasonal average

  19. Turbine blade with spar and shell

    DOE Patents [OSTI]

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

    2012-04-24

    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.

  20. Obtaining superhydrophobicity using commercial razor blades

    E-Print Network [OSTI]

    Ken Yamamoto; Hideyuki Takezawa; Satoshi Ogata

    2015-08-06

    Because the superhydrophobic characteristic appears by forming a composite surface consisting of solid and air underneath the droplets, a large number of rough surfaces that can trap air have been fabricated. Recently, the air trapping on materials whose equilibrium contact angles are less than 90 degrees was achieved by fabricating proper structures that lead energetic stability at the condition. Whereas these methods were proposed under the assumption of the static and equilibrium conditions, we take a dynamic and non-equilibrium approach in this study through droplet deposition and droplet impact experiments. By employing test surfaces that consist of commercially available stainless steel razor blades, we show the pinning effect brings the apparent water contact angle of approximately 160 degrees on a "hydrophilic" substrate. We call this state the "non-equilibrium Cassie state" and give theoretical explanations. Furthermore, the dynamic characteristics of the droplet impact on these surfaces are discussed in a range of moderate Weber numbers.

  1. Obtaining superhydrophobicity using commercial razor blades

    E-Print Network [OSTI]

    Yamamoto, Ken; Ogata, Satoshi

    2015-01-01

    Because the superhydrophobic characteristic appears by forming a composite surface consisting of solid and air underneath the droplets, a large number of rough surfaces that can trap air have been fabricated. Recently, the air trapping on materials whose equilibrium contact angles are less than 90 degrees was achieved by fabricating proper structures that lead energetic stability at the condition. Whereas these methods were proposed under the assumption of the static and equilibrium conditions, we take a dynamic and non-equilibrium approach in this study through droplet deposition and droplet impact experiments. By employing test surfaces that consist of commercially available stainless steel razor blades, we show the pinning effect brings the apparent water contact angle of approximately 160 degrees on a "hydrophilic" substrate. We call this state the "non-equilibrium Cassie state" and give theoretical explanations. Furthermore, the dynamic characteristics of the droplet impact on these surfaces are discusse...

  2. 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

  3. Turbine Blade Row Optimization Through Endwall Contouring by an Adjoint Method

    E-Print Network [OSTI]

    Liu, Feng

    function, regardless of the number of design parameters. Flow loss through the blade row is minimized while blade at off-design conditions is also evaluated and compared with that of the original blade algorithms (GAs) [4­6] aregaining usage in practical engineering design of turbomachinery blade rows. Besides

  4. "Comparative Environmental Assessment of Conventional Materials and Wood for the Fabrication of Wind Turbine Blades"

    E-Print Network [OSTI]

    Mountziaris, T. J.

    of Wind Turbine Blades" Yashira M. Valentín Feliciano Mentor: Peggi Clouston Graduate Student: Rachel Koh of the turbine blades. Wind turbine blades are commonly made of carbon fiber and fiberglass, which are materials wind energy demands, wood is being evaluated for incorporation into wind turbine blades, since

  5. Gas turbine blade with intra-span snubber

    DOE Patents [OSTI]

    Merrill, Gary B.; Mayer, Clinton

    2014-07-29

    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.

  6. The height of watermelons with wall

    E-Print Network [OSTI]

    Thomas Feierl

    2012-04-11

    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.

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

    SciTech Connect (OSTI)

    2010-02-02

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

  8. Flame Height Measurement of Laminar Inverse Diffusion Flames

    E-Print Network [OSTI]

    Mikofski, Mark A.; Williams, Timothy C.; Shaddix, Christopher R.; Blevins, Linda G.

    2006-01-01

    Flame Height Measurement of Laminar Inverse Diffusion Flamesinverse diffusion flame, laminar, flame height, OH, laserair and methane-air laminar inverse diffusion flames were

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

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

    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...

  10. 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

    2010-01-01

    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.

  11. 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 ...

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

    E-Print Network [OSTI]

    Coly, P

    2012-01-01

    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.

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

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

    Recovery and Reinvestment Act and the state of Massachusetts, the WTTC is the first test facility in the world with the ability to test blades up to 90 m in length. The...

  14. Determining effects of turbine blades on fluid motion

    DOE Patents [OSTI]

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

    2012-05-01

    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.

  15. Determining effects of turbine blades on fluid motion

    DOE Patents [OSTI]

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

    2011-05-31

    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.

  16. Development of a morphing helicopter blade with electrochemical actuators

    E-Print Network [OSTI]

    Tubilla Kuri, Fernando

    2007-01-01

    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, ...

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

    E-Print Network [OSTI]

    Li, Shiou-Jiuan

    2012-12-07

    . 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...

  18. Horizontal-Axis Wind Turbine Wake Sensitivity to Different Blade...

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

    U inflow angle at blade section relative to plane of rotation + , degrees angular velocity of rotor, rads SW iF T Scaled Wind Farm Technology x time average of...

  19. 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.

    2005-12-01

    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.

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

    E-Print Network [OSTI]

    Phoenix, Casey J. (Casey John)

    2007-01-01

    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 ...

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

    E-Print Network [OSTI]

    Deilmann, Christian

    2009-01-01

    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 ...

  2. Aerodynamic testing of a rotating wind turbine blade

    SciTech Connect (OSTI)

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

    1990-01-01

    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.

  3. 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

  4. The Materiality and ‘Enchantment’ of the Gebel el-Arak Knife and the Gerzean Flint Blade Production

    E-Print Network [OSTI]

    Kim, Patricia E.

    2012-01-01

    a similar reading of the design of the blade as a landscape.structure, the design of the flint blade has a high valueof the design and the color of the blade (Figure 11) appear

  5. 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

    2012-08-28

    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.

  6. Blade platform seal for ceramic/metal rotor assembly

    DOE Patents [OSTI]

    Wertz, John L. (Indianapolis, IN)

    1982-01-01

    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.

  7. Maximum output at minimum cost

    E-Print Network [OSTI]

    Firestone, Jeremy

    Gamesa G90-2.0 MW #12;Maximum output at minimum cost per kWh for low wind sites ®® Class IIIA mast and the electrical substation. This innovative modular design based on TCP/IP architecture has

  8. Near wall cooling for a highly tapered turbine blade

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2011-03-08

    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.

  9. Test evaluation of a laminated wood wind turbine blade concept

    SciTech Connect (OSTI)

    Faddoul, J.R.

    1981-05-01

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

  10. 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

    2014-06-03

    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.

  11. Dual-axis resonance testing of wind turbine blades

    DOE Patents [OSTI]

    Hughes, Scott; Musial, Walter; White, Darris

    2014-01-07

    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.

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

    E-Print Network [OSTI]

    Collin, Jean E., 1978-

    2004-01-01

    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 ...

  13. Optimal Design and Tolerancing of Compressor Blades Subject to Manufacturing Variability

    E-Print Network [OSTI]

    Wang, Qiqi

    This paper presents a computational approach for optimal robust design and tolerancing of turbomachinery compressor blades that are subject to geometric variability. This approach simultaneously determines the optimal blade ...

  14. Retention system and method for the blades of a rotary machine

    DOE Patents [OSTI]

    Pedersen, Poul D. (Cincinnati, OH); Glynn, Christopher C. (Hamilton, OH); Walker, Roger C. (Piedmont, SC)

    2002-01-01

    A retention system and method for the blades of a rotary machine for preventing forward or aft axial movement of the rotor blades includes a circumferential hub slot formed about a circumference of the machine hub. The rotor blades have machined therein a blade retention slot which is aligned with the circumferential hub slot when the blades are received in correspondingly shaped openings in the hub. At least one ring segment is secured in the blade retention slots and the circumferential hub slot to retain the blades from axial movement. A key assembly is used to secure the ring segments in the aligned slots via a hook portion receiving the ring segments and a threaded portion that is driven radially outwardly by a nut. A cap may be provided to provide a redundant back-up load path for the centrifugal loads on the key. Alternatively, the key assembly may be formed in the blade dovetail.

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

    E-Print Network [OSTI]

    Townsend, Jessica Lee

    2004-01-01

    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 ...

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

    E-Print Network [OSTI]

    Rallabandi, Akhilesh P.

    2010-10-12

    -1 PARAMETRIC STUDY OF TURBINE BLADE INTERNAL COOLING AND FILM COOLING A Dissertation by AKHILESH PRABHAKAR RALLABANDI Submitted to the O?ce of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR... OF PHILOSOPHY August 2010 Major Subject: Mechanical Engineering PARAMETRIC STUDY OF TURBINE BLADE INTERNAL COOLING AND FILM COOLING A Dissertation by AKHILESH PRABHAKAR RALLABANDI Submitted to the O?ce of Graduate Studies of Texas A&M University in partial...

  17. 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..................................................................4 Stiffener Design Considerations

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

    DOE Patents [OSTI]

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

    2006-10-10

    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.

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

    E-Print Network [OSTI]

    Lackner, Matthew, 1980-

    2004-01-01

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

  20. Improved blade profile loss and deviation angle models for advanced transonic compressor bladings. Part 1: A model for subsonic flow

    SciTech Connect (OSTI)

    Koenig, W.M.; Hennecke, D.K.; Fottner, L.

    1996-01-01

    New blading concepts as used in modern transonic axial-flow compressors require improved loss and deviation angle correlations. The new model presented in this paper incorporates several elements and treats blade-row flows having subsonic and supersonic inlet conditions separately. In the first part of this paper two proved and well-established profile loss correlations for subsonic flows are extended to quasi-two-dimensional conditions and to custom-tailored blade designs. Instead of a deviation angle correlation, a simple method based on singularities is utilized. The comparison between the new model and a recently published model demonstrates the improved accuracy in prediction of cascade performance achieved by the new model.

  1. 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

  2. EFFECT OF MEAN STRESS ON THE DAMAGE OF WIND TURBINE BLADES* Herbert J. Sutherland

    E-Print Network [OSTI]

    1 EFFECT OF MEAN STRESS ON THE DAMAGE OF WIND TURBINE BLADES* Herbert J. Sutherland Sandia National, MT 59717 johnm@coe.montana.edu ABSTRACT In many analyses of composite wind turbine blades in wind turbine blades has been released recently. This diagram, which is based on the MSU/DOE Fatigue

  3. 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

  4. Reducing Uncertainty in Wind Turbine Blade Health Inspection with Image Processing Techniques

    E-Print Network [OSTI]

    McCalley, James D.

    Reducing Uncertainty in Wind Turbine Blade Health Inspection with Image Processing Techniques Huiyi problems Promotion Meet cool peopleBetter jobs Academia Vs Industry #12;Wind Turbine Blade Health damage Source: Sørensen, 2004 BASF coating for wind turbine blades, 2014 Coating layer health

  5. 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

  6. 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

  7. 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

  8. Structural Testing of 9 m Carbon Fiber Wind Turbine Research Blades*

    E-Print Network [OSTI]

    Structural Testing of 9 m Carbon Fiber Wind Turbine Research Blades* Joshua Paquette Sandia Laboratory** , Golden, CO, 80401 Three 9 m carbon fiber wind turbine blades have been designed through Systems Consulting (GEC) , Dynamic Design Engineering , and MDZ Consulting§§ ; and seven blades from each

  9. 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...

  10. CHARACTERISTIC p ANALOGUE OF MODULES WITH FINITE CRYSTALLINE HEIGHT

    E-Print Network [OSTI]

    Abrashkin, Victor

    CHARACTERISTIC p ANALOGUE OF MODULES WITH FINITE CRYSTALLINE HEIGHT Victor Abrashkin1 Abstract of Galois modules with crystalline height h N. If h = 1 these modules appear as geometric points[K]-modules with crystalline height h. Examples of such modules are given by subquotients of crystalline representations of K

  11. DEVELOPMENTS IN LARGE BLADES FOR LOWER COST WIND TURBINES

    E-Print Network [OSTI]

    of the WindPACT project, the Blade System Design Studies developed innovations in manufacturing, materials capacity is a companion drop in the cost of wind energy (COE). The current cost of wind-produced power. 3). Wind produced power currently i

  12. " *.--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

  13. Mixing blade system for high-resistance media

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-07-09

    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.

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

    ScienceCinema (OSTI)

    Felker, Fort

    2014-06-10

    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.

  15. 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

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

    SciTech Connect (OSTI)

    Felker, Fort

    2013-11-13

    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.

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

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

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

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

    SciTech Connect (OSTI)

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

    2008-01-01

    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.

  19. Fabrication of low-cost Mod-0A wood-composite wind-turbine blades

    SciTech Connect (OSTI)

    Lark, R.F.; Gougeon, M.; Thomas, G.; Zuteck, M.

    1983-02-01

    A contract was awarded to Gougeon Brothers, Inc., by NASA Lewis Research Center, under Department of Energy sponsorship, for the development and fabrication of two 60-foot, low-cost wood composite blades for service on a 200-kW Mod-0A wind turbine machine. The contractural effort consisted of blade design and analysis and fabrication phases. This report provides a brief summary of the design and analysis phase, and an indepth review of the blade fabrication phase. The wood composite blades were fabricated by using epoxy resin-bonded laminates of Douglas fir veneers for the leading edge spar sections and honeycomb-cored birch plywood panels for the blade trailing edge or afterbody sections. The blade was joined to the wind turbine hub assembly by epoxy resin-bonded steel load takeoff studs. The wood composite blades were installed in the newest Mod-0A wind turbine test facility at Kukuku, Hawaii called Makini Huila (wind wheel) by the Hawaiians. The wood composite blades have successfully completed high power (average of 150 kW) operations for an 18-month period (nearly 8000 h) prior to replacement with another set of wood composite blades. The original set of blades were taken out of service because of the failure of the shank on one stud. An inspection of the blades at NASA Lewis showed that the shank failure was caused by a high stress concentration at a corrosion pit on the shank fillet radius which resulted in fatigue stresses in excess of the endurance limit. The remainder of the blade, including the embedded portion of the fractured stud, and the entire wood structure was found to be in excellent condition. All of the remaining studs, with the exception of four studs that showed an onset of corrosion, were also in excellent condition. The failed stud, as well as four of the corroded studs were successfully replaced with new studs. The blade is currently in a service-ready condition.

  20. 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)

    2011-07-12

    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.

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

    E-Print Network [OSTI]

    Leutwyler, Cooke Hearon

    1965-01-01

    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...

  2. Trailing edge noise theory for rotating blades in uniform flow

    E-Print Network [OSTI]

    Sinayoko, Samuel; Agarwal, Anurag

    2013-01-01

    This paper presents a new formulation for trailing edge noise radiation from rotating blades based on an analytical solution of the convective wave equation. It accounts for distributed loading and the effect of mean flow and spanwise wavenumber. A commonly used theory due to Schlinker and Amiet (1981) predicts trailing edge noise radiation from rotating blades. However, different versions of the theory exist; it is not known which version is the correct one and what the range of validity of the theory is. This paper addresses both questions by deriving Schlinker and Amiet's theory in a simple way and by comparing it to the new formulation, using model blade elements representative of a wind turbine, a cooling fan and an aircraft propeller. The correct form of Schlinker and Amiet's theory (1981) is identified. It is valid at high enough frequency, i.e. for a Helmholtz number relative to chord greater than one and a rotational frequency much smaller than the angular frequency of the noise sources.

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

    SciTech Connect (OSTI)

    Carlson, Clinton P; Schichting, Alexander D; Quellette, Scott; Farinholt, Kevin M; Park, Gyuhae

    2009-10-05

    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.

  4. 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

    2010-11-08

    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.

  5. The height and range of watermelons without wall

    E-Print Network [OSTI]

    Thomas Feierl

    2009-04-03

    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".

  6. 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

  7. Objects of maximum electromagnetic chirality

    E-Print Network [OSTI]

    Fernandez-Corbaton, Ivan

    2015-01-01

    We introduce a definition of the electromagnetic chirality of an object and show that it has an upper bound. The upper bound is attained if and only if the object is transparent for fields of one handedness (helicity). Additionally, electromagnetic duality symmetry, i.e. helicity preservation upon scattering, turns out to be a necessary condition for reciprocal scatterers to attain the upper bound. We use these results to provide requirements for the design of such extremal scatterers. The requirements can be formulated as constraints on the polarizability tensors for dipolar scatterers or as material constitutive relations. We also outline two applications for objects of maximum electromagnetic chirality: A twofold resonantly enhanced and background free circular dichroism measurement setup, and angle independent helicity filtering glasses.

  8. Sandia Energy - The Influence of Rotor Blade Design on Wake Developmen...

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

    Influence of Rotor Blade Design on Wake Development Home Renewable Energy Energy SWIFT Facilities News Wind Energy News & Events Systems Analysis Systems Engineering The Influence...

  9. A comparison of baseline aerodynamic performance of optimally-twisted versus non-twisted HAWT blades

    SciTech Connect (OSTI)

    Simms, D.A.; Robinson, M.C.; Hand, M.M.; Fingersh, L.J.

    1995-01-01

    NREL has completed the initial twisted blade field tests of the ``Unsteady Aerodynamics Experiment.`` This test series continues systematic measurements of unsteady aerodynamic phenomena prevalent in stall-controlled horizontal axis wind turbines (HAWTs). The blade twist distribution optimizes power production at a single angle of attack along the span. Abrupt transitions into and out of stall are created due to rapid changes in inflow. Data from earlier experiments have been analyzed extensively to characterize the steady and unsteady response of untwisted blades. In this report, a characterization and comparison of the baseline aerodynamic performance of the twisted versus non-twisted blade sets will be presented for steady flow conditions.

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

    SciTech Connect (OSTI)

    Schreck, S. J.

    2007-01-01

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

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

    SciTech Connect (OSTI)

    Griffin, Dayton A.

    2009-05-01

    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.

  12. Baoding Tianwei Wind Power Blade Co Ltd | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar Energy LLC Jump to:Greece:Bajo en Carbono, MexicoBanham PoultryBlade Co Ltd

  13. The maximum multiflow problems with bounded fractionality

    E-Print Network [OSTI]

    Hirai, Hiroshi

    (Karzanov 98) frac(| ) = frac(K2 + Kn) = 4 (Lomonsov 04) frac( ) =? Hiroshi Hirai The maximum multiflow

  14. 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.

    2010-12-01

    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.

  15. 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 Großmann1 , 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

  16. Etude de l'impact sur pale d'hlicoptre Study of impact on helicopter blade

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Etude de l'impact sur pale d'hélicoptère Study of impact on helicopter blade I. Tawk 1 , J in structures similar to sections of helicopter blades subjected to an impact. These complex composite from 30 to 130 m / s. The tests are recorded by a camera that allows acquisitions of 120,000 fps

  17. 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 the expected cycle range for turbines. While the data cannot be used directly in design due to the specialized AND RESULTS Introduction Composite wind turbine blade materials may experience between 108 to 109 significant

  18. 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 for apwise loads on three horizontal axis wind tur- binesHAWTs. In the case of two of these turbines

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

    E-Print Network [OSTI]

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

  20. "Biomaterials for Use in Large Scale Wind Turbine Blades" Malia Charter

    E-Print Network [OSTI]

    Mountziaris, T. J.

    "Biomaterials for Use in Large Scale Wind Turbine Blades" Malia Charter Advising: Rachel Koh, Dr into the feasibility of using biocomposites for wind turbine blades. While bast fiber composites are also being Peggi Clouston Wind energy is growing rapidly to address concerns of non-renewable energy resources. One

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

    SciTech Connect (OSTI)

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

    2014-07-01

    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.

  2. 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 on the compressor. Three dierent axial spacings between the rotor and the upstream blade row have been simulated of Cincinnati, Cincinnati, OH, 45221 In order to accurately model the physics associated with losses

  3. 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

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

    E-Print Network [OSTI]

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

  5. 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 (SHM) systems. Different methods have been developed for detection of damages in WT blades. However a damage detection method based on autocorrelations of response accelerations. The damage sensitive feature

  6. 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 consists of three 3 metre long vertically aligned blades each fixed to the central shaft by two horizontal

  7. 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

  8. 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

  9. 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

  10. 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

  11. Construction of low-cost, Mod-0A wood-composite wind-turbine blades

    SciTech Connect (OSTI)

    Lark, R.F.

    1983-01-01

    The construction of two sixty-foot, low-cost, wood composite blades for service on 200 kW Mod-0A wind turbines is described. The blades were constructed of epoxy resin-bonded Douglas fir veneers for the leading edge sections, and paper honeycomb-cored, birch plywood faced panels for the afterbody sections. The blades were joined to the wind turbine hub by epoxy resin-bonded steel load take-off studs embedded into the root end of the blades. The blades were installed on the 200 kW Mod-0A wind turbine facility at Kahuku, Hawaii. The blades have completed nearly 8000 hours of operation over an 18 month period at an average power of 150 kW prior to replacement with another set of wood composite blades. The blades were replaced because of a corrosion failure of the steel shank on one stud. Inspections at NASA-Lewis showed that the wood composite structure remains in excellent condition.

  12. Structural Testing of 9 m Carbon Fiber Wind Turbine Research Blades*

    E-Print Network [OSTI]

    National Laboratories , Albuquerque, NM, 87111 Jeroen van Dam§ and Scott Hughes§ National Renewable Energy a research program initiated by Sandia National Laboratories. The individual designs feature such innovations of these blades were conducted at the National Wind Technology Center. The blades were subjected to flapwise

  13. 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 oscillations and with the tower bending tendency. Keywords: LQG control, Wind turbines, Multi-objective control

  14. IBM's mainframe-blade hybrid to do Windows Tighter server coupling coming?

    E-Print Network [OSTI]

    Spruth, Wilhelm G.

    IBM's mainframe-blade hybrid to do Windows Tighter server coupling coming? By Timothy Prickett Morgan , Posted 12th January 2011 IBM is rejiggering its hybrid mainframe-blade "system of systems board, which IBM calls a processor book. Up to four books and 3TB of DDR3 main memory (including a RAID

  15. 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 method Huiyi Zhang1 , John Jackman Wind Energy Manufacturing Laboratory Dept. of Industrial technique was investigated to assess its ability to detect surface flaws on an on-tower wind turbine blade

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

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

    Home > Edison's Desk > 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...

  17. Hierarchical occlusion culling for arbitrarily-meshed height fields 

    E-Print Network [OSTI]

    Edmondson, Paul Michael

    2004-09-30

    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 ...

  18. DEVELOPMENT OF PROTECTIVE COATINGS FOR SINGLE CRYSTAL TURBINE BLADES

    SciTech Connect (OSTI)

    Amarendra K. Rai

    2006-12-04

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

  19. 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

    2010-01-01

    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.

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

    DOE Patents [OSTI]

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

    1983-12-20

    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.

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

    E-Print Network [OSTI]

    Cahalane, Patrick Takeo

    1985-01-01

    EFFECTS OF MORKING ARM HEIGHTS AND AGE ON BLOOD PRESSURE A Thesis PATRICK TAKEO CAHALANE Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1985 Major... Subject: Industrial Engineering EFFECTS OF WORKING ARM HEIGHTS AND AGE ON BLOOD PRESSURE A Thesis by PATRICK TAKEO CAHALANE Approved as to stvle and content by: Dr. R. Dale Huchi son (Chairman of Committee) Dr. Rodger J. Koppa (Member) Dr. R...

  2. 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

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

    SciTech Connect (OSTI)

    Steward, W. Gene

    1999-11-14

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

  4. 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

  5. Investigation of Flying-Height Stability of Thermal Fly-Height Control Sliders in Lubricant or Solid Contact with Roughness

    E-Print Network [OSTI]

    Zheng, Jinglin; Bogy, David B.

    2010-01-01

    Gonzaga, L. , Man, Y.J. : Lubricant-sur?ng recording and itsSlider dynamics in the lubricant-contact regime. IEEE Trans.Height Control Sliders in Lubricant or Solid Contact with

  6. Evaluation of Aeroelastically Tailored Small Wind Turbine Blades Final Project Report

    SciTech Connect (OSTI)

    Griffin, Dayton A.

    2005-09-29

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

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

    SciTech Connect (OSTI)

    Cairns, Douglas S.; Riddle, Trey; Nelson, Jared

    2011-02-01

    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.

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

    DOE Patents [OSTI]

    Twerdochlib, M.

    1999-02-02

    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.

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

    E-Print Network [OSTI]

    Khan, A. M. M. Farid

    1957-01-01

    and Electronic Relay 17 6. 7 ~ 8. View of the Instrument Panel Racking Arrangement Spacer and Packing Types 23 23 10. Effect of Tower Height on Range/Approach Ratio for Rectangular Packing 35 Effect of Tower Height on Range/Approach Rptio for Circular... - round type packing 33 VI. Average results ? triangular packing with vertex up 34 SYMBOLS ALUB ABB?', 'VIATIO&IS mass air flow rate, pounds per (hour)(unit ground area) h" ent'halpy of saturated ai- at water temperature, Btu per pound of dry air. ha...

  10. Maximum-Likelihood Stereo Correspondence using Field

    E-Print Network [OSTI]

    MacLean, W. James

    Maximum-Likelihood Stereo Correspondence using Field Programmable Gate Arrays Siraj Sabihuddin & W. James MacLean Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario be performed using a maximum- likelihood formulation. One such formulation has been presented by Cox [1], who

  11. MAXIMUM ENTROPY APPROACH TO OPTIMAL SENSOR PLACEMENT

    E-Print Network [OSTI]

    Kreinovich, Vladik

    MAXIMUM ENTROPY APPROACH TO OPTIMAL SENSOR PLACEMENT FOR AEROSPACE NON-DESTRUCTIVE TESTING R discussed for space struc- tures. Key words: Non-destructive testing, maximum entropy, aerospace structures not have a sufficient number of them, so additional sensors must be placed to test the structural integrity

  12. Improved performance rhenium containing single crystal alloy turbine blades utilizing ppm levels of the highly reactive elements lanthanum and yttrium

    SciTech Connect (OSTI)

    Ford, D.A.; Fullagar, K.P.L.; Bhangu, H.K. [Rolls-Royce PLC, Bristol (United Kingdom); Thomas, M.C.; Burkholder, P.S.; Korinko, P.S. [Allison Engine Co., Indianapolis, IN (United States); Harris, K.; Wahl, J.B. [Cannon-Muskegon Corp., MI (United States)

    1999-01-01

    Turbine inlet temperatures have now approached 1650 C at maximum power for the latest large commercial turbofan engines, resulting in high fuel efficiency and thrust levels approaching or exceeding 445 kN (100,000 lbs.). High reliability and durability must be intrinsically designed into these turbine engines to meet operating economic targets and ETOPS certification requirements. Re additions to cast airfoil superalloys not only improve creep and thermomechanical fatigue strength but also environmental properties, including coating performance. It is now known that sulfur (S) at levels <10 ppm but >0.2 ppm in these alloys reduces the adherence of {alpha} alumina protective scales on these materials or their coatings by weakening the Van der Waal`s bond between the scale and the alloy substrate. A team approach has been used to develop an improvement to CMSX-4 alloy which contains 3% Re, by reducing S and phosphorus (P) levels in the alloy to <2 ppm, combined with residual additions of lanthanum (La) + yttrium (Y) in the range 10--30 ppm. Results from cyclic, burner rig dynamic oxidation testing at 1093 C show thirteen times the number of cycles to initial alumina scale spallation for CMSX-4 [La + Y] compared to standard CMSX-4. The La assists with ppm chemistry control of the Y throughout the single crystal turbine blade castings through the formation of a continuous lanthanum oxide film between the molten and solidifying alloy and the ceramic core and prime coat of the shell mold. Y and La tie up the M2 ppm but >0.2 ppm residual S in the alloy as very stable Y and La sulfides and oxysulfides, thus preventing diffusion of the S atoms to the alumina scale layer under high temperature, cyclic oxidizing conditions. La also forms a stable phosphide. CMSX-4 (ULS) (La + Y) HP shroudless turbine blades will commence engine testing in May 1998.

  13. fan blades Karr, O.F.; Brooks, J.B.; Seay, E. 20 FOSSIL-FUELED...

    Office of Scientific and Technical Information (OSTI)

    draft fan blades Karr, O.F.; Brooks, J.B.; Seay, E. 20 FOSSIL-FUELED POWER PLANTS; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 42 ENGINEERING NOT INCLUDED IN OTHER...

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

    E-Print Network [OSTI]

    Margetts, David (David Lawrence)

    2008-01-01

    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 ...

  15. 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.

    2014-09-01

    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.

  16. Effects of trailing edge flap dynamic deployment on blade-vortex interactions 

    E-Print Network [OSTI]

    Nelson, Carter T.

    1997-01-01

    A theoretical and experimental investigation is undertaken to determine the effects of an actively deployable trailing edge flap on the disturbances created during blade-vortex interactions (BVI). The theoretical model consists of an unsteady panel...

  17. An adaptive mesh method for the simulation of Blade Vortex Interaction 

    E-Print Network [OSTI]

    Kim, Kyu-Sup

    1998-01-01

    An adaptive mesh method for the simulation of parallel ics. Blade Vortex Interaction (BV1) with an active Trailing Edge Flap (TEF) is presented. The two-dimensional 1111-steady problem is solved by a higher order upwind Euler method...

  18. 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 degrees of damage. Excitation was performed in two ways: near the delamination zone to demonstrate their performance. We explore methods for determining damage. We first explore results

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

    SciTech Connect (OSTI)

    Deines, Krystal E; Marinone, Timothy; Schultz, Ryan A; Farinholt, Kevin M; Park, Gyuhae

    2011-01-24

    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.

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

    SciTech Connect (OSTI)

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

    2004-06-01

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

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

    E-Print Network [OSTI]

    Chen, Chang

    2013-05-08

    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...

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

    SciTech Connect (OSTI)

    Sutherland, H.; Beattie, A.; Hansche, B.; Musial, W.; Allread, J.; Johnson, J.; Summers, M.

    1994-06-01

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

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

    E-Print Network [OSTI]

    Collard, Joseph Eugene

    2000-01-01

    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 ...

  4. Recovery Act-Funded 90-m Blade Test Facility Commissioned May...

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

    nation to test blades longer than 50 meters, which previously could only be done in Europe or China. The WTTC tests for structural integrity and durability, and can reduce wind...

  5. 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

  6. 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 and providing longer turbine life GE's unique electronics provide transmission efficiencies and enable harmonious function within the local grid Allows wind turbines to stay on line generating power, even during

  7. Impact of wind gusts on sea surface height in storm

    E-Print Network [OSTI]

    Vries, Hans de

    Impact of wind gusts on sea surface height in storm surge situations. Jonsmod, May 2010 Rikke van der Grinten (KNMI/IMAU) Hans de Vries (KNMI) Huib de Swart (IMAU) #12;2 Jonsmod, May 2010 Wind forcing winds from HiRLAM Drag relation, Charnock relation: with: #12;Jonsmod, May 2010 Wind stress · Assumption

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

    E-Print Network [OSTI]

    Suarez, D Orozco; Bueno, J Trujillo

    2015-01-01

    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.

  9. Computing canonical heights on Von der Universitat Bayreuth

    E-Print Network [OSTI]

    Stoll, Michael

    for the explicit computation of canonical heights on Ja- cobians of smooth projective curves. Building on an existing algorithm due to Flynn and Smart with modifications by Stoll we generalize efficient methods generality, building on earlier work due to Flynn, and a careful study of the local N´eron models

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

    E-Print Network [OSTI]

    Minchak, Scott Alan

    2009-06-02

    from reaping grass after 1500 strokes; (c) NNWXP2, reaping grass polish after 1000 strokes. Scales: 100x = 200 um; 200x = 100 um; and 500x = 50 um................33 5 Experimental Blade: (a) NWXP3, polish from cleaning sinew; (b...) NWXP4, polish from cutting rawhide. Scales: 100x = 200 um; 200x = 100 um; and 500x = 50 um..................................36 6 Experimental Blades: (a) GRT 4-1, polish from scraping wood; (b) NNWXP1, polish from sawing wood. Scales...

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

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw; Pierce, Kirk Gee

    2006-10-17

    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.

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

    SciTech Connect (OSTI)

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

    2011-10-01

    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.

  13. Flutter analysis of a cascade of staggered blades in subsonic flow 

    E-Print Network [OSTI]

    Kronenberger, Louis

    1977-01-01

    . DEDICATION To Lynda, Michelle, and Kellie. TABLE OF CONTENTS ABSTRACT ACKNOWLEDGEMENTS DEDICATION TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES NOMENCLATURE INTRODUCTION AERODYNAMIC THEORY General Boundary Conditions Numerical Procedure... Variation on Aerodynamic Deri vati ves 26 2 Effect of Blade Segment Variation on Aerodynamic Derivatives 28 3 Summary of Two Degree of Freedom Flutter Analysis 46 LIST OF FIGURES Fi gure Cascade of Airfoi1s Blade Coordinates Two Degree of Freedom...

  14. 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

    2010-10-04

    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.

  15. Viscous throughflow modeling of axial compressor bladerows using a tangential blade force hypothesis

    SciTech Connect (OSTI)

    Gallimore, S.J.

    1998-10-01

    This paper describes the modeling of axial compressor blade rows in an axisymmetric viscous throughflow method. The basic method, which has been reported previously, includes the effects of spanwise mixing, using a turbulent diffusion model, and endwall shear within the throughflow calculation. The blades are modeled using a combination of existing two-dimensional blade performance predictions for loss and deviation away from the annulus walls and a novel approach using tangential blade forces in the endwall regions. Relatively simple assumptions about the behavior of the tangential static pressure force imposed by the blades allow the secondary deviations produced by tip clearance flows and the boundary layer flows at fixed blade ends to be calculated in the axisymmetric model. Additional losses are assigned in these regions based on the calculated deviations. The resulting method gives realistic radial distributions of loss and deviation across the whole span at both design and off-design operating conditions, providing a quick method of estimating the magnitudes of these effects in the preliminary design process. Results from the method are compared to measured data in low and high-speed compressors and multistage three-dimensional viscous CFD predictions.

  16. Non-Destructive Evaluation of Wind Turbine Blades Using an Infrared Camera

    SciTech Connect (OSTI)

    Beattie, A.G.; Rumsey, M.

    1998-12-17

    The use of a digital infrared as a non-destructive evaluation thermography camera (NDE) tool was ex- plored in two separate wind turbine blade fatigue tests. The fwst test was a fatigue test of part of a 13.1 meter wood-epoxy-composite blade. The second test was on a 4.25 meter pultruded fiber glass blade section driven at several mechanical resonant frequencies. The digital infrared camera can produce images of either the static temperature distribution on the surface of the specimen, or the dynamic temperature distribution that is in phase with a specific frequency on a vibrating specimen. The dynamic temperature distribution (due to thermoplastic effects) gives a measure of the sum of the principal stresses at each point on the surface. In the wood- epoxy-composite blade fatigue test, the point of ultimate failure was detected long before failure occurred. The mode shapes obtained with the digital infrared camera, from the resonant blade tests, were in very good agree- ment with the finite-element calculations. In addition, the static temperature images of the resonating blade showed two areas that contained cracks. Close-up dy- namic inf%red images of these areas showed the crack structure that agreed with subsequent dye-penetrant analysis.

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

    SciTech Connect (OSTI)

    Butterfield, C.P.

    1988-11-01

    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.

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

    E-Print Network [OSTI]

    Wilkinson, Mark

    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

  19. Local Mass and Heat Transfer on a Turbine Blade Tip

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jin, P.; Goldstein, R. J.

    2003-01-01

    Local mass and heat transfer measurements on a simulated high-pressure turbine blade-tip surface are conducted in a linear cascade with a nonmoving tip endwall, using a naphthalene sublimation technique. The effects of tip clearance (0.86–6.90% of chord) are investigated at various exit Reynolds numbers (4–7 × 10 5 ) and turbulence intensities (0.2 and 12.0%). The mass transfer on the tip surface is significant along its pressure edge at the smallest tip clearance. At the two largest tip clearances, the separation bubble on the tip surface can cover the wholemore »width of the tip on the second half of the tip surface. The average mass-transfer rate is highest at a tip clearance of 1.72% of chord. The average mass-transfer rate on the tip surface is four and six times as high as on the suction and the pressure surface, respectively. A high mainstream turbulence level of 12.0% reduces average mass-transfer rates on the tip surface, while the higher mainstream Reynolds number generates higher local and average mass-transfer rates on the tip surface.« less

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

    SciTech Connect (OSTI)

    Snowberg, D.; Hughes, S.

    2013-04-01

    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.

  1. 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.

    2006-05-01

    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.

  2. Building Height-Characteristics in Three U.S. Cities

    SciTech Connect (OSTI)

    Burian, S. J.; Brown, M. J.; Velugubantla, S. P.

    2002-01-01

    Urban canopy parameterizations have been used to represent urban effects in numerical models of mesoscale meteorology, the surface energy budget, and pollutant dispersion. The urban canopy parameterization accounts for the drag exerted by urban roughness elements, the enhancement of turbulent kinetic energy, and the alteration of the surface energy budget (Brown 2000). Accurate representation of urban effects in numerical simulations requires the determination of urban morphological parameters, including building height statistics. Computer analysis of 3-D building digital datasets can provide details of the urban environment in an efficient manner. Ratti ut al. (2001) describe a method for obtaining urban canopy parameters from digital imagery using image processing techniques, Burian et al. (2002) present an alternative analysis approach using a geographic information system (GIS). In this paper, building height statistics computed for three U.S. cities following the GIS approach are presented.

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

    SciTech Connect (OSTI)

    Faddoul, J.R.

    1983-01-01

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

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

    SciTech Connect (OSTI)

    Galib Abumeri; Frank Abdi

    2012-02-16

    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

  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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEtGeorgia:Illinois: Energy ResourcesTurboPowerPortalHeights, Iowa: Energy

  6. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEtGeorgia:Illinois:WizardYates County, NewYorktown Heights, New York: Energy

  7. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainableGlynnMassachusetts:Ohio: Energy Resources JumpHartsville,Harwood Heights,

  8. Hasbrouck 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainableGlynnMassachusetts:Ohio: Energy ResourcesHasbrouck Heights, New Jersey:

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

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    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainable UrbanKentucky: Energy Resources JumpGarfield Heights, Ohio: Energy

  10. Sewickley Heights, Pennsylvania: 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing Capacity for Low Emission DevelopmentLakes,Sewickley Heights, Pennsylvania:

  11. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing Capacity forSiliciumEnergy IncAshburnham,BoundChicago Heights, Illinois:

  12. Cell development obeys maximum Fisher information

    E-Print Network [OSTI]

    B. R. Frieden; R. A. Gatenby

    2014-04-29

    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.

  13. 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

    2012-06-28

    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.

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

    DOE Patents [OSTI]

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

    2013-12-10

    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.

  15. Bayesian and Maximum Likelihood Neural Networks

    E-Print Network [OSTI]

    Nielsen, Finn Årup

    Bayesian and Maximum Likelihood Neural Networks Finn A ffi rup Nielsen Section for Digital Signal, linear output, Gaussian distribution ] \\Gamma 1;+1[ ffl Binary (binary classification), tanh on output, bino­ mial distribution. ] \\Gamma 1; +1[ ffl Classification, softmax function on outputs [Bridle, 1990

  16. Partitioned algorithms for maximum likelihood and

    E-Print Network [OSTI]

    Smyth, Gordon K.

    Partitioned algorithms for maximum likelihood and other nonlinear estimation Gordon K. Smyth There are a variety of methods in the literature which seek to make iterative estimation algorithms more manageable by breaking the iterations into a greater number of simpler or faster steps. Those algorithms which deal

  17. On maximum matching width Jisu Jeong (KAIST)

    E-Print Network [OSTI]

    Kim, Yong Jung

    ;Graph width parameters · tree-width (Halin 1976, Robertson and Seymour 1984) · branch-width (Robertson and Seymour 1991) · carving-width (Seymour and Thomas 1994) · clique-width (Courcelle and Olariu 2000) · rank-width (Oum and Seymour 2006) · maximum matching-width (Vatshelle 2012) #12;a b c d e fg hi j A tree

  18. Postsunset rise of F layer height in the equatorial region and its relation to the F layer dynamo polarization fields

    SciTech Connect (OSTI)

    Goel, M.K.; Singh, S.S.; Rao, B.C.N. (National Physical Lab., New Delhi (India))

    1990-05-01

    The ionosonde data are studied for equatorial station, Thumba, to delineate various features of the evening height rise of F layer. Sharp increase of h'F and h{sub p}F2 is observed in the postsunset period for high solar activity. Seasonal variation is observed in this increase of h'F and it is maximum for equinox months. For summer months, there is a delay of about an hour in the time of occurrence of h'F (peak) as compared to winter and equinox months. This delay is shown to be associated with the delay in sunset times in the conjugate E regions. As for magnetic activity dependence, it is found that this height increase is less pronounced for disturbed days for winter and equinox whereas for summer it is marginally higher over the quiet day values. Further, it is observed that the value of h'F (peak) during disturbed periods is almost at the same value of 350 km for all the three seasons. Thus the seasonal variation of magnetic activity effects appears to be mainly governed by the average seasonal variation for quiet times. The increase in F layer height is due to zonal eastward electric fields developed after sunset which is believed to be due to F region dynamo fields. While the main driving force for these fields is the zonal neutral winds, the development of these fields depend on the ratio of the F region to E region conductivity and the longitudinal gradient in the E region conductivity. Experimental observations of both the neutral winds and ionospheric conductivities are examined for their variation with solar activity, season and magnetic activity as both these factors will contribute for the various observed features of the height rise.

  19. 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

    2014-04-25

    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. 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.

  1. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: Energy Resources JumpNewTexas: Energy Resources Jump to:Huber Heights, Ohio: Energy

  2. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: Energy Resources JumpNew Jersey: Energy ResourcesHoboken,Holden, Maine:CityHeights,

  3. Glenn Heights, Texas: 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainable UrbanKentucky:BoreOpenGilliamOhio: Energy Resources JumpGlenmont,Heights,

  4. Lincoln 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma, Arizona:Oregon: Energy Resources Jump to:Heights, Ohio: Energy Resources

  5. Island Heights, New Jersey: Energy Resources | Open Energy Information

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    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: Energy ResourcesOrder at 8, 13RenewableIrem Geothermal PowerBioIselin,Heights, New

  6. Porter Heights, Texas: Energy Resources | Open Energy Information

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    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland:NPIProtectio1975) |Texas: EnergyOklahoma:Ewen, NewPortageHeights, Texas: Energy

  7. Property:Building/InteriorHeight | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland:NPIProtectio1975)EnergyFloorAreaOffices Jump to:FloorAreaTotalInteriorHeight

  8. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland:NPI VenturesNewSt.Information Olinda Landfill GasIOlowalu-UkumehameHeights,

  9. Berlin Heights, Ohio: Energy Resources | Open Energy Information

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    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental JumpInformation BeaufortBent County,Benton,Berks County,Heights, Ohio: Energy

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

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    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmentalBowerbank, Maine: EnergyEnergy Information Bronze Boot SpaNewNewHeights, Ohio:

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

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    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (Utility Company) Jump to:NewMinnesota: Energy ResourcesIndia PvtHeights, Ohio:

  12. Alamo Heights, Texas: Energy Resources | Open Energy Information

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    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowaWisconsin: Energy ResourcesAirAlamo Heights, Texas: Energy Resources Jump

  13. Property:GBIG/MinHeight | Open Energy Information

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  14. 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

    2015-01-01

    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.

  15. 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

    2010-10-30

    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.

  16. NOAA Technical Memorandum NMFS-SEFSC-570 ESTIMATION OF EFFORT, MAXIMUM SUSTAINABLE YIELD, AND MAXIMUM

    E-Print Network [OSTI]

    , AND MAXIMUM ECONOMIC YIELD IN THE SHRIMP FISHERY OF THE GULF OF MEXICO BY JAMES NANCE, WALTER KEITHLY, JR YIELD, AND MAXIMUM ECONOMIC YIELD IN THE SHRIMP FISHERY OF THE GULF OF MEXICO BY JAMES NANCE, WALTER in the shrimp fishery of the Gulf of Mexico. NOAA Technical Memorandum NMFS-SEFSC-570, 71P. Copies may

  17. 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)

    2008-03-18

    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.

  18. X-ray microdiffraction study of martensit-retained austenite microstructures at the tip of a steel blade.

    SciTech Connect (OSTI)

    Cai, Z.; Lai, B.; Ilinski, P.; Legnini, D.; Yun, W.; Experimental Facilities Division; Xradia

    2001-01-01

    The x-ray microdiffraction technique was used to study lattice-strain field and phase concentration near the surface of a carburised steel blade on a micron-length scale. Our results show larger compressive lattice strains and more completed phase transformation at the location near the tip of the blade than that the locations away from the tip.

  19. 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

    2014-06-24

    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.

  20. 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

  1. 46th Aerospace Sciences Meeting, January 7-10, 2008, Reno, Nevada A Smart Wind Turbine Blade Using Distributed

    E-Print Network [OSTI]

    Nelson, Robert C.

    of "smart" wind turbine blades with integrated sensor-actuator-controller modules to im- prove the performance of wind turbines. The system will be designed to enhance energy capture, and reduce aerodynamic46th Aerospace Sciences Meeting, January 7-10, 2008, Reno, Nevada A Smart Wind Turbine Blade Using

  2. Deposition of hole-transport materials in solid-state dye-sensitized solar cells by doctor-blading

    E-Print Network [OSTI]

    McGehee, Michael

    Solution processing a b s t r a c t We report using doctor-blading to replace conventional spin coating)-9,90 -spirobifluorene) in solid-state dye-sensitized solar cells. Doctor-blading is a roll-to-roll compatible, large-area coating technique, is capable of achieving the same spiro-OMeTAD pore filling fraction

  3. 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)

    2010-12-01

    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.

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

    E-Print Network [OSTI]

    Garion, C

    2013-01-01

    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.

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

    SciTech Connect (OSTI)

    James, T.; Goodrich, A.

    2013-12-01

    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.

  6. Zipf's law, power laws, and maximum entropy

    E-Print Network [OSTI]

    Visser, Matt

    2012-01-01

    Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplines - from astronomy to demographics to economics to linguistics to zoology, and even warfare. A recent model of random group formation [RGF] attempts a general explanation of such phenomena based on Jaynes' notion of maximum entropy applied to a particular choice of cost function. In the present article I argue that the cost function used in the RGF model is in fact unnecessarily complicated, and that power laws can be obtained in a much simpler way by applying maximum entropy ideas directly to the Shannon entropy subject only to a single constraint: that the average of the logarithm of the observable quantity is specified.

  7. Maximum Estrada Index of Bicyclic Graphs

    E-Print Network [OSTI]

    Wang, Long; Wang, Yi

    2012-01-01

    Let $G$ be a simple graph of order $n$, let $\\lambda_1(G),\\lambda_2(G),...,\\lambda_n(G)$ be the eigenvalues of the adjacency matrix of $G$. The Esrada index of $G$ is defined as $EE(G)=\\sum_{i=1}^{n}e^{\\lambda_i(G)}$. In this paper we determine the unique graph with maximum Estrada index among bicyclic graphs with fixed order.

  8. "FINITE ELEMENT ANALYSIS ASSISTED HOT BAR BLADE DESIGN," Jack. Zhou, Li Zhuang, Zongyan He, and Daniel Herscovici, International Conference of Flexible automation and Intelligent Manufacturing, UMD,

    E-Print Network [OSTI]

    Zhou, Jack

    "FINITE ELEMENT ANALYSIS ASSISTED HOT BAR BLADE DESIGN," Jack. Zhou, Li Zhuang, Zongyan He, Maryland, June 2000. FINITE ELEMENT ANALYSIS ASSISTED HOT BAR BLADE DESIGN Jack. Zhou, Li Zhuang in fabrication of cellular phones for many years. The existing hot bar blade design has two defects

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

    E-Print Network [OSTI]

    turbine blades up to 90 meters in length. A critical factor to wind turbine design and development is the ability to test new designs, components, and materials. In addition, wind turbine blade manufacturers are required to test their blades as part of the turbine certification process. The National Renewable Energy

  10. Maximum entropy analysis of cosmic ray composition

    E-Print Network [OSTI]

    Nosek, Dalibor; Vícha, Jakub; Trávní?ek, Petr; Nosková, Jana

    2016-01-01

    We focus on the primary composition of cosmic rays with the highest energies that cause extensive air showers in the Earth's atmosphere. A way of examining the two lowest order moments of the sample distribution of the depth of shower maximum is presented. The aim is to show that useful information about the composition of the primary beam can be inferred with limited knowledge we have about processes underlying these observations. In order to describe how the moments of the depth of shower maximum depend on the type of primary particles and their energies, we utilize a superposition model. Using the principle of maximum entropy, we are able to determine what trends in the primary composition are consistent with the input data, while relying on a limited amount of information from shower physics. Some capabilities and limitations of the proposed method are discussed. In order to achieve a realistic description of the primary mass composition, we pay special attention to the choice of the parameters of the sup...

  11. North York (Yonge Street) building outlines with heights, clutter data, DEM, contours and places

    E-Print Network [OSTI]

    Title: North York (Yonge Street) building outlines with heights, clutter data, DEM, contours heights, contours, building outlines, landmarks, points of interest Restrictions: Data is licensed for use@yorku.ca) Citation: RMSI. "[North York (Yonge Street) building outlines with heights, clutter data, DEM, contours

  12. A comparison of methods used to estimate the height of sand dunes on Mars

    E-Print Network [OSTI]

    Bourke, Mary C.

    A comparison of methods used to estimate the height of sand dunes on Mars M.C. Bourke a,b,, M bodies is difficult. We assess four methods that can be used to estimate the height of aeolian dunes of which were not previously available for dunes on Mars. They include dune height, width, length, surface

  13. 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

  14. Comparison of MISR and MODIS cloud-top heights in the presence of cloud overlap

    E-Print Network [OSTI]

    Baum, Bryan A.

    Comparison of MISR and MODIS cloud-top heights in the presence of cloud overlap C.M. Naud a, , B July 2006; accepted 3 September 2006 Abstract Coincident MISR and MODIS cloud-top heights retrieved March 2000 and October 2003. The difference between MODIS and MISR cloud-top heights is assessed

  15. Oxidation State Optimization for Maximum Efficiency of NOx Adsorber...

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

    State Optimization for Maximum Efficiency of NOx Adsorber Catalysts Oxidation State Optimization for Maximum Efficiency of NOx Adsorber Catalysts Presentation given at the 16th...

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

    SciTech Connect (OSTI)

    George, R.L.

    1984-02-01

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

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

    E-Print Network [OSTI]

    Yu, Wenbin

    tool for effective design and analysis of wind turbine blades. 1 Introduction Wind energy is becoming increase of the wind power's share of the world's electricity generation since 1996.? Over the same period Engineer, Endowed Chair of Wind Energy at Institute of Aircraft Design 1 #12;system, composite materials

  18. 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. Finally, I would like to thank Sandia National Laboratories for supporting this research and the wind turbine energy project. #12;v TABLE OF CONTENTS LIST OF TABLES

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

    DOE Patents [OSTI]

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

    2008-06-03

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

    E-Print Network [OSTI]

    1 Mixed Mode Static and Fatigue Crack Growth in Wind Blade Paste Adhesives Daniel D. Samborsky, static GIc and mixed mode fracture, and fatigue crack growth resistance. I. Introduction Wind turbine, then adhesively bonded together. The large size coupled with cost constraints result in bond lines at least

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

    E-Print Network [OSTI]

    Cincinnati, University of

    loaded upstream blade row and its eect on the compressor. Three dierent axial spacings between the rotor by Research Professor Mark G. Turner In order to accurately model the physics associated with losses in a transonic compressor, a time-accurate simulation of a transonic compressor rig was developed. Parameters

  2. 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". The mid and far spacings represent typical axial gaps found in operational fans and compressors. However behind a stator are modeled. The model is based on a Burger vortex core model for shed vortices

  3. 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

  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. VP 100: New Facility in Boston to Test Large-Scale Wind Blades

    Broader source: Energy.gov [DOE]

    Thanks in part to funding from the Recovery Act, the Wind Technology Testing Center in Massachusetts will be first in the U.S. to test wind turbine blades up to 300 feet in length -- creating 300 construction jobs and 30 permanent design jobs in the process.

  6. American Institute of Aeronautics and Astronautics ACOUSTIC EMISSION MONITORING OF A WIND TURBINE BLADE

    E-Print Network [OSTI]

    turbine blade are cracking in the bond between two pieces of the structure, such as a joint between a spar and the skin, and tears in the skin or a spar. Both involve the progressive fracture of many fibers. AE has

  7. 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.

    2014-06-01

    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.

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

    SciTech Connect (OSTI)

    Zhang, Ding; Han, Xiaoyan; Newaz, Golam

    2014-02-18

    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.

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

    Office of Energy Efficiency and Renewable Energy (EERE)

    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.

  10. Maximum Performance Group MPG | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation, searchScotland JumpPlantation Elec Co JumpIAEAOpenMaximum

  11. A vibrating razor blade machining tool for material removal on low- density foams

    SciTech Connect (OSTI)

    Hillyer, D.F. Jr.

    1990-10-01

    The Lawrence Livermore National Laboratory (LLNL) has developed an accurate method of machining low-density foams into rectangular blank shapes by using a commercial oscillating razor blade machining tool concept marketed as a Vibratome. Since 1970, Vibratome has been used by medical laboratories to section fresh or fixed animal and plant tissues without freezing or embedding. By employing a vibrating razor blade principle, Vibratome sectioning avoids the alteration of morphology and the destruction of enzyme activities. The patented vibrating blade principle moves the sectioning razor blade in a reciprocating arcuate path as it penetrates the specimen. Sectioning takes place in a liquid bath using an ordinary injector-type razor blade. Although other commercial products may accomplish the same task, the Vibratome concept is currently being used at LLNL to obtain improved foam surface qualities from razor machining by combining state-of-the-art air bearing hardware with precise linear motion and an electrodynamic exciter that generates sinusoidal excitation. Razor cut foam surfaces of less than 25 {mu}m (0.001 in.) flatness are achieved over areas of 8.75 in.{sup 2} (2.5 {times} 3.5 in.). Razor machining of wide or narrow foam surfaces is generally characterized by a continuous curl chip for the full length of the material removed. This continuous chip facilitates flatness and prevents increased surface densities caused by material chip collection often left in the surface cells by conventional machine tools. This report covers the design evolution of razor machining of non-metallic soft materials. Hardware that maintains close dimensional tolerances and concurrently leaves the machined surface free of physical property changes is described. 20 figs.

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

    SciTech Connect (OSTI)

    CAIRNS,DOUGLAS S.; SHRAMSTAD,JON D.

    2000-06-01

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

  13. 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

    2007-07-31

    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.

  14. Genetic Determinants of Height Growth Assessed Longitudinally from Infancy to Adulthood in the Northern Finland Birth Cohort 1966

    E-Print Network [OSTI]

    Peltonen, Leena

    Recent genome-wide association (GWA) studies have identified dozens of common variants associated with adult height. However, it is unknown how these variants influence height growth during childhood. We derived peak height ...

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

    SciTech Connect (OSTI)

    Chen, Jizhou

    2009-05-09

    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

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

    SciTech Connect (OSTI)

    Berry, Derek

    2007-09-01

    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.

  17. Evaluation of WRF predicted near hub-height winds and ramp events over a Pacific Northwest site with complex terrain

    SciTech Connect (OSTI)

    Yang, Qing; Berg, Larry K.; Pekour, Mikhail S.; Fast, Jerome D.; Newsom, Rob K.; Stoelinga, Mark; Finley, Cathy

    2013-08-16

    The WRF model version 3.3 is used to simulate near hub-height winds and power ramps utilizing three commonly used planetary boundary-layer (PBL) schemes: Mellor-Yamada-Janji? (MYJ), University of Washington (UW), and Yonsei University (YSU). The predicted winds have small mean biases compared with observations. Power ramps and step changes (changes within an hour) consistently show that the UW scheme performed better in predicting up ramps under stable conditions with higher prediction accuracy and capture rates. Both YSU and UW scheme show good performance predicting up- and down- ramps under unstable conditions with YSU being slightly better for ramp durations longer than an hour. MYJ is the most successful simulating down-ramps under stable conditions. The high wind speed and large shear associated with low-level jets are frequently associated with power ramps, and the biases in predicted low-level jet explain some of the shown differences in ramp predictions among different PBL schemes. Low-level jets were observed as low as ~200 m in altitude over the Columbia Basin Wind Energy Study (CBWES) site, located in an area of complex terrain. The shear, low-level peak wind speeds, as well as the height of maximum wind speed are not well predicted. Model simulations with 3 PBL schemes show the largest variability among them under stable conditions.

  18. Turbulent heat transfer and friction in a segmental channel that simulates leading-edge cooling channels of modern turbine blades 

    E-Print Network [OSTI]

    Spence, Rodney Brian

    1995-01-01

    Experiments are conducted to study the effects of channel geometry and asymmetric heating on the heat transfer and friction characteristics of turbulent flows in leading edge cooling channels in stator blades of gas turbines. The leading edge...

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

    SciTech Connect (OSTI)

    Naughton, Jonathan W.

    2014-08-05

    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.

  20. 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)

    2014-01-01

    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 ...

  1. 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

  2. Dynamics and Stability of Thermal Flying-height Control Sliders in Hard Disk Drives

    E-Print Network [OSTI]

    Zheng, Jinglin

    2012-01-01

    Height Control Sliders in Lubricant or Solid Contact withmolecularly thin liquid lubricant films on slider hysteresisC. M. Mate, et al. , "Lubricant-Induced Spacing Increases at

  3. Height, adiposity and body fat distribution and breast density in young women

    E-Print Network [OSTI]

    2012-01-01

    Longitudinal association of anthropometry with mammographicwere measured by anthropometry and dual-energy X- rayor poor positioning. Anthropometry Breast density Height was

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

    SciTech Connect (OSTI)

    Francis A. Di Bella

    2010-06-01

    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.

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

    SciTech Connect (OSTI)

    Barone, Matthew Franklin

    2011-08-01

    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.

  6. Numerical Investigation of Flapwise-Torsional Vibration Model of a Smart Section Blade with Microtab

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Nailu; Balas, Mark J.; Yang, Hua; Jiang, Wei; Magar, Kaman T.

    2015-01-01

    This study presents a method to develop an aeroelastic model of a smart section blade equipped with microtab. The model is suitable for potential passive vibration control study of the blade section in classic flutter. Equations of the model are described by the nondimensional flapwise and torsional vibration modes coupled with the aerodynamic model based on the Theodorsen theory and aerodynamic effects of the microtab based on the wind tunnel experimental data. The aeroelastic model is validated using numerical data available in the literature and then utilized to analyze the microtab control capability on flutter instability case and divergence instabilitymore »case. The effectiveness of the microtab is investigated with the scenarios of different output controllers and actuation deployments for both instability cases. The numerical results show that the microtab can effectively suppress both vibration modes with the appropriate choice of the output feedback controller.« less

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

    SciTech Connect (OSTI)

    Janet M. Twomey, PhD

    2010-04-30

    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.

  8. 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)

    2008-04-01

    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.

  9. Boundary Shape Control of Navier-Stokes Equations and Geometrical Design Method for Blade's Surface in the Impeller

    E-Print Network [OSTI]

    Kaitai Li; Jian Su; Liquan Mei

    2008-01-22

    In this paper A Geometrical Design Method for Blade's surface $\\Im$ in the impeller is provided here $\\Im$ is a solution to a coupling system consisting of the well-known Navier-Stokes equations and a four order elliptic boundary value problem . The coupling system is used to describe the relations between solutions of Navier-Stokes equations and the geometry of the domain occupied by fluids, and also provides new theory and methods for optimal geometric design of the boundary of domain mentioned above. This coupling system is the Eular-Lagrange equations of the optimal control problem which is describing a new principle of the geometric design for the blade's surface of an impeller. The control variable is the surface of the blade and the state equations are Navier-Stokes equations with mixed boundary conditions in the channel between two blades. The objective functional depending on the geometry shape of blade's surface describes the dissipation energy of the flow and the power of the impeller. First we prove the existence of a solution of the optimal control problem. Then we use a special coordinate system of the Navier-Stokes equations to derive the objective functional which depends on the surface $\\Theta$ explicitly. We also show the weakly continuity of the solution of the Navier-Stokes equations with respect to the geometry shape of the blade's surface.

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

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Romero Gomez, Pedro DJ

    2014-12-08

    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.

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

    SciTech Connect (OSTI)

    Seryi, A

    2003-10-02

    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.

  12. 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.

    2005-11-30

    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.

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

    SciTech Connect (OSTI)

    Romero Gomez, Pedro DJ; Richmond, Marshall C.

    2014-06-16

    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.

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

    SciTech Connect (OSTI)

    Taylor, Stuart G; Farinholt, Kevin M; Park, Gyuhae; Farrar, Charles R; Todd, Michael D

    2009-01-01

    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.

  15. Manufacturing process modeling for composite materials and structures, Sandia blade reliability collaborative

    SciTech Connect (OSTI)

    Guest, Daniel A.; Cairns, Douglas S.

    2014-02-01

    The increased use and interest in wind energy over the last few years has necessitated an increase in the manufacturing of wind turbine blades. This increase in manufacturing has in many ways out stepped the current understanding of not only the materials used but also the manufacturing methods used to construct composite laminates. The goal of this study is to develop a list of process parameters which influence the quality of composite laminates manufactured using vacuum assisted resin transfer molding and to evaluate how they influence laminate quality. Known to be primary factors for the manufacturing process are resin flow rate and vacuum pressure. An incorrect balance of these parameters will often cause porosity or voids in laminates that ultimately degrade the strength of the composite. Fiber waviness has also been seen as a major contributor to failures in wind turbine blades and is often the effect of mishandling during the lay-up process. Based on laboratory tests conducted, a relationship between these parameters and laminate quality has been established which will be a valuable tool in developing best practices and standard procedures for the manufacture of wind turbine blade composites.

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

    SciTech Connect (OSTI)

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

    2014-01-01

    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.

  17. 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

    2015-01-01

    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...

  18. Statistical optimization for passive scalar transport: maximum entropy production vs maximum Kolmogorov-Sinay entropy

    E-Print Network [OSTI]

    Martin Mihelich; Berengere Dubrulle; Didier Paillard; Davide Faranda

    2015-05-26

    We derive rigorous results on the link between the principle of maximum entropy production and the principle of maximum Kolmogorov-Sinai entropy using a Markov model of the passive scalar diffusion called the Zero Range Process. We show analytically that both the entropy production and the Kolmogorov-Sinai entropy seen as functions of f admit a unique maximum denoted fmaxEP and fmaxKS. The behavior of these two maxima is explored as a function of the system disequilibrium and the system resolution N. The main result of this article is that fmaxEP and fmaxKS have the same Taylor expansion at _rst order in the deviation of equilibrium. We find that fmaxEP hardly depends on N whereas fmaxKS depends strongly on N. In particular, for a fixed difference of potential between the reservoirs, fmaxEP (N) tends towards a non-zero value, while fmaxKS (N) tends to 0 when N goes to infinity. For values of N typical of that adopted by Paltridge and climatologists we show that fmaxEP and fmaxKS coincide even far from equilibrium. Finally, we show that one can find an optimal resolution N_ such that fmaxEP and fmaxKS coincide, at least up to a second order parameter proportional to the non-equilibrium uxes imposed to the boundaries.

  19. 3D electroplated microstructures fabricated by a novel height control method

    E-Print Network [OSTI]

    Lin, Liwei

    is coated and patterned to open the designated areas for electroplating. Nickel electroplating is performed3D electroplated microstructures fabricated by a novel height control method L.-W. Pan, P. Yuen, L. Lin Abstract A 3D electroplating process by means of pixel- wise, step height control of selective

  20. 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

  1. Downtown Toronto building outlines with heights, clutter data, DEM, contours and places

    E-Print Network [OSTI]

    Title: Downtown Toronto building outlines with heights, clutter data, DEM, contours and places Data, building outlines, landmarks, points of interest Restrictions: Data is licensed for use of York University. "[Downtown Toronto building outlines with heights, clutter data, DEM, contours and places]" [electronic

  2. A comparison of computational and experimental lift-off heights of coflow laminar diffusion flames

    E-Print Network [OSTI]

    Long, Marshall B.

    A comparison of computational and experimental lift-off heights of coflow laminar diffusion flames*), and excited-state OH (denoted OH*) are imaged in coflow laminar diffusion flames. Measurements are made both was performed, which indicates that the lift-off height is sensitive to the laminar flame speed

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

    E-Print Network [OSTI]

    Trueblood, Andrew Tyson

    2009-01-01

    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 ...

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

    E-Print Network [OSTI]

    J. McDonnell; N. Schunck; W. Nazarewicz

    2013-01-31

    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.

  5. Amplification of Tsunami Heights by Delayed Rupture of Great Earthquakes along the Nankai Trough

    E-Print Network [OSTI]

    Furumura, Takashi

    Amplification of Tsunami Heights by Delayed Rupture of Great Earthquakes along the Nankai Trough of delayed rupture of great earthquakes along the Nankai trough on tsunami heights on the Japanese coast. As the tsunami source, we used a model of the 1707 Hoei earthquake, which consists of four segments: Tokai

  6. Systems and methods that generate height map models for efficient three dimensional reconstruction from depth information

    DOE Patents [OSTI]

    Frahm, Jan-Michael; Pollefeys, Marc Andre Leon; Gallup, David Robert

    2015-12-08

    Methods of generating a three dimensional representation of an object in a reference plane from a depth map including distances from a reference point to pixels in an image of the object taken from a reference point. Weights are assigned to respective voxels in a three dimensional grid along rays extending from the reference point through the pixels in the image based on the distances in the depth map from the reference point to the respective pixels, and a height map including an array of height values in the reference plane is formed based on the assigned weights. An n-layer height map may be constructed by generating a probabilistic occupancy grid for the voxels and forming an n-dimensional height map comprising an array of layer height values in the reference plane based on the probabilistic occupancy grid.

  7. Boundary Shape Control of Navier-Stokes Equations and Geometrical Design Method for Blade's Surface in the Impeller

    E-Print Network [OSTI]

    Li, Kaitai; Mei, Liquan

    2008-01-01

    In this paper A Geometrical Design Method for Blade's surface $\\Im$ in the impeller is provided here $\\Im$ is a solution to a coupling system consisting of the well-known Navier-Stokes equations and a four order elliptic boundary value problem . The coupling system is used to describe the relations between solutions of Navier-Stokes equations and the geometry of the domain occupied by fluids, and also provides new theory and methods for optimal geometric design of the boundary of domain mentioned above. This coupling system is the Eular-Lagrange equations of the optimal control problem which is describing a new principle of the geometric design for the blade's surface of an impeller. The control variable is the surface of the blade and the state equations are Navier-Stokes equations with mixed boundary conditions in the channel between two blades. The objective functional depending on the geometry shape of blade's surface describes the dissipation energy of the flow and the power of the impeller. First we pro...

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

    E-Print Network [OSTI]

    Parthasarathy, Nikhil Kaushik

    2004-09-30

    and accurate predictions of whirl amplitudes, maximum contact load and stress in the bearings, transmissibility, thermal growths, maximum and minimum damper pressures and the amount of unbalanced force for incipient oil film cavitation. It requires about 4...

  9. 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.

    2011-01-04

    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.

  10. The effect of blade tenderization on the palatability and retail caselife of beef steaks 

    E-Print Network [OSTI]

    Huerta, Nelson Orlando

    1976-01-01

    subcutaneous fat and discolored muscle surfaces. Section C was sprayed with an acidified chlorine solution. A steak was removed prior to tenderization from each subprimal section and used as a control. Tenderized steaks (2X) were obtained from each section... ldg . t? ea(s . : i(cn co, ?. pare ' to untri;. med . -ac(p les IJo si ~nificant effect on bacterial counts w. . s observed due to blade tenderization treat. "cent . . ('. bactericidal or bacter'ostatic effect of chlorine rin ing wa. s observed (P...

  11. Examination of forced unsteady separated flow fields on a rotating wind turbine blade

    SciTech Connect (OSTI)

    Huyer, S. [Univ. of Colorado, Boulder, CO (US)] [Univ. of Colorado, Boulder, CO (US)

    1993-04-01

    The wind turbine industry faces many problems regarding the construction of efficient and predictable wind turbine machines. Steady state, two-dimensional wind tunnel data are generally used to predict aerodynamic loads on wind turbine blades. Preliminary experimental evidence indicates that some of the underlying fluid dynamic phenomena could be attributed to dynamic stall, or more specifically to generation of forced unsteady separated flow fields. A collaborative research effort between the University of Colorado and the National Renewable Energy Laboratory was conducted to systematically categorize the local and global effects of three- dimensional forced unsteady flow fields.

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

    E-Print Network [OSTI]

    Umberto Lucia

    2010-11-17

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

  13. Maximum-principle-satisfying second order discontinuous Galerkin ...

    E-Print Network [OSTI]

    2014-05-05

    Notice that the CFL conditions in Table 2.1 are sufficient but not necessary to achieve maximum principle. A more efficient implementation would be enforcing

  14. EERE Takes Important Steps to Ensure Maximum Impact of Technology...

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

    in wind, solar and other programs is essential to achieve maximum return for taxpayer investment. | Photos courtesy of the National Renewable Energy Laboratory Tracking...

  15. 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.

    2014-12-01

    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.

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

    E-Print Network [OSTI]

    Geiger, David William

    2004-09-30

    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 ...

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

    E-Print Network [OSTI]

    Beck, Andy Dwayne

    2001-01-01

    . 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...

  18. (lOpts) 1. An inverted conical tank whose diameter is 8 In and height ...

    E-Print Network [OSTI]

    (lOpts) 1. An inverted conical tank whose diameter is 8 In and height 10 n1 contains crude oil that is leaking out the bottom at a rate of 5 m3 / hr. How fast is the ...

  19. Development and assessment of a coupled strategy for conjugate heat transfer with Large Eddy Simulation: Application to a cooled turbine blade

    E-Print Network [OSTI]

    Nicoud, Franck

    Simulation: Application to a cooled turbine blade F. Duchaine a,*, A. Corpron b , L. Pons b , V. Moureau b parameters. The coupled tool is then applied to a cooled turbine blade model where results demonstrate both walls is an important phenomenon in combustion chambers and a main design constraint in gas turbines

  20. Structural Testing at the NWTC Helps Improve Blade Design and Increase System Reliability; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    2015-08-01

    Since 1990, the National Renewable Energy Laboratory’s (NREL's) National Wind Technology Center (NWTC) has tested more than 150 wind turbine blades. NWTC researchers can test full-scale and subcomponent articles, conduct data analyses, and provide engineering expertise on best design practices. Structural testing of wind turbine blades enables designers, manufacturers, and owners to validate designs and assess structural performance to specific load conditions. Rigorous structural testing can reveal design and manufacturing problems at an early stage of development that can lead to overall improvements in design and increase system reliability.

  1. 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.

    2015-01-01

    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.

  2. 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)]

    Karen Johnson; Michael Jensen

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

  3. Predicting Customer Behavior using Naive Bayes and Maximum Entropy

    E-Print Network [OSTI]

    Keysers, Daniel

    of returned goods, we additionally generated two binary features for zero and missing values. The remaining Naive Bayes, Maximum Entropy, Neural Networks and Logistic Regression for classification of cus- tomer classifiers won the Data-Mining-Cup in 2004. Combining Logistic Regression, Neural Networks, and Maximum

  4. Maximum oxidative phosphorylation capacity of the mammalian heart

    E-Print Network [OSTI]

    Mootha, Vamsi K.

    Maximum oxidative phosphorylation capacity of the mammalian heart VAMSI K. MOOTHA, ANDREW E. ARAI, AND ROBERT S. BALABAN Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National. Maximum oxidative phosphorylation capacity of the mammalian heart. Am. J. Physiol. 272 (Heart Circ

  5. A comparison of cloud top heights computed from airborne lidar and MAS radiance data using CO2 slicing

    E-Print Network [OSTI]

    Baum, Bryan A.

    A comparison of cloud top heights computed from airborne lidar and MAS radiance data using CO2]. Other studies have compared CO2- slicing cloud heights with those computed from lidar data [Smith in assessing the accuracy of the CO2-slicing cloud height algorithm. Infrared measurements of upwelling

  6. 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; Lavdas, E; Kostopoulos, S; Ninos, C; Strikou, A; Glotsos, D; Vlachopoulou, A; Oikonomou, G; Economopoulos, N; Roka, V; Sakkas, G; Tsagkalis, A; Batsikas, G; Statkahis, S; Papanikolaou, N

    2014-06-01

    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.

  7. 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 cooling ducts with ribs, so­called turbulators. It is investigated how these ribs influence the heat the quality of these cooling ducts. 1 Introduction Gas turbines play an important role in aviation

  8. 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

    2009-05-15

    at the highest rotation number of 0.58. Heat transfer coefficients are also experimentally measured in a wedge-shaped cooling channel (Dh =2.22cm, Ac=7.62cm2) to model an internal cooling passage near the trailing edge of a gas turbine blade where the coolant...

  9. 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

  10. 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.

    2014-04-17

    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.

  11. Maximum Instantaneous Power Estimation by Subgraph Coloring UCSD CSE Dept.

    E-Print Network [OSTI]

    Liu, Bao

    cycle helps in building a maximum envelope currents waveform for each net and providing a MIP upper process technology advancement integrates millions of gates on a single chip and introduces increasing

  12. Multi-Class Classification with Maximum Margin Multiple Kernel

    E-Print Network [OSTI]

    Mohri, Mehryar

    (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

  13. A magmatic trigger for the Paleocene-Eocene thermal maximum?

    E-Print Network [OSTI]

    Dubin, Andrea Rose

    2015-01-01

    Fifty-six million years ago Earth experienced rapid global warming (~6°C) that was caused by the release of large amounts of carbon into the ocean-atmosphere system. This Paleocene-Eocene Thermal Maximum (PETM) is often ...

  14. Maximum likelihood analysis of low energy CDMS II germanium data

    E-Print Network [OSTI]

    Agnese, R.

    We report on the results of a search for a Weakly Interacting Massive Particle (WIMP) signal in low-energy data of the Cryogenic Dark Matter Search experiment using a maximum likelihood analysis. A background model is ...

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

    E-Print Network [OSTI]

    Bruzek, Alison K. (Allison Kim)

    2013-01-01

    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 ...

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

    SciTech Connect (OSTI)

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

    2012-07-01

    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.

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

    SciTech Connect (OSTI)

    Wang, Jy-An John; Ren, Fei; Tan, Ting; Mandell, John; Agastra, Pancasatya

    2011-11-01

    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.

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

    E-Print Network [OSTI]

    Henryk Gzyl; Enrique ter Horst

    2007-09-04

    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.

  19. Supply Chain and Blade Manufacturing Considerations in the Global Wind Industry

    Broader source: Energy.gov [DOE]

    Over the past decade, significant wind manufacturing capacity has been built in the United States in response to an increasingly large domestic market. Recent U.S. manufacturing production levels exceed anticipated near-term domestic demand for select parts of the supply chain, in part due to policy uncertainty, and this is resulting in some restructuring in the industry. Factor location decisions are influenced by a combination of quantitative and qualitative factors; proximity to end-markets is often a key consideration, especially for manufacturers of large wind turbine components. Technology advancements in the wind sector are continuing , and larger blade designs are being pursued in the market, which may increase U.S.-based manufacturing opportunities.

  20. An analysis of axial compressor fouling and a blade cleaning method

    SciTech Connect (OSTI)

    Tarabrin, A.P.; Schurovsky, V.A.; Bodrov, A.I.; Stalder, J.P.

    1998-04-01

    The paper describes the phenomenon of axial compressor fouling due to aerosols contained in the air. Key parameters having effect on the level of fouling are determined. A mathematical model of a progressive compressor fouling using the stage-by-stage calculation method is developed. Calculation results on the influence of fouling on the compressor performance are presented. A new index of sensitivity of axial compressors to fouling is suggested. The paper gives information about Turbotect`s deposit cleaning method of compressor blading and the results of its application on an operating industrial gas turbine. Regular on-line and off-line washings of the compressor flow path made it possible to maintain a high level of engine efficiency and output.

  1. Laboratory Experiments on the Effects of Blade Strike from Hydrokinetic Energy Technologies on Larval and Juvenile Freshwater Fishes

    SciTech Connect (OSTI)

    Schweizer, Peter E; Cada, Glenn F; Bevelhimer, Mark S

    2012-03-01

    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

  2. Heat rate and maximum load capability improvements through cycle isolation

    SciTech Connect (OSTI)

    Coons, K. [Coronado Generating Station, Saint Johns, AZ (United States); Dimmick, J.G. [Leak Detection Services, Inc., Annapolis, MD (United States)

    1995-06-01

    Major improvements in maximum load capability and gross turbine heat rate were obtained at Salt River Project`s Coronado Unit 1, resulting from work done during the Spring 1993 overhaul. Corrected maximum load increased by 13.1 MW -- from 403.8 MW prior to the overhaul compared to 416.9 MW after the overhaul. Corrected gross turbine heat rate was reduced 270 BTU/kWH -- from 7,920 BTU/kWH before the overhaul to 7,650 BTU/kWH after the overhaul. Of the work done, the repair of leaking valves had the largest impact on cycle performance. The reduction of cycle leakage accounted for an increase of 9.9 MW in maximum load capability and a reduction to gross turbine heat rate of 190 BTU. Weekly maximum load tests, which started in August 1992 with the installation of an on-line monitoring system, show that maximum load had decreased approximately 4 MW during the six months prior to the overhaul. During this time there were no significant changes in HP or IP efficiencies, or any other directly-measured cycle parameters. Therefore, this degradation was attributed to cycle isolation valve leakage. Acoustic emission leak detection methods were used to identify leaking valves prior to the outage. Of the 138 valves tested for leakage, 31 valves had medium to very large leaks. Of these 31 leaking valves identified, 30 were repaired or replaced.

  3. WIDTH AND MODE OF THE PROFILE FOR RANDOM TREES OF LOGARITHMIC HEIGHT1

    E-Print Network [OSTI]

    Devroye, Luc

    Science Academia Sinica Taipei 115 Taiwan August 21, 2005 Abstract We propose a new, direct, correlation by a grant from National Science Council. 1 #12;1 Introduction Most random trees in the discrete probability literature have height either of order p n or of order log n (n being the tree size); see Aldous (1991

  4. Title: York University building outlines with heights and clutter (land use) data Data Creator /

    E-Print Network [OSTI]

    Title: York University building outlines with heights and clutter (land use) data Data Creator(s): April 2010 Updates: N/A Abstract: Data consists of: 3D Building Outlines in the York University Keele. Clutter data categories include: 1 Inland Water 2 Open 3 Low tree density 4 High Tree density 5 Buildings

  5. Laser altimeter canopy height profiles Methods and validation for closed-canopy, broadleaf forests

    E-Print Network [OSTI]

    Lefsky, Michael

    Laser altimeter canopy height profiles Methods and validation for closed-canopy, broadleaf forests November 2000 Abstract Waveform-recording laser altimeter observations of vegetated landscapes provide a time-resolved measure of laser pulse backscatter energy from canopy surfaces and the underlying ground

  6. Semiclassical theory of Coulomb blockade peak heights in chaotic quantum dots Evgenii E. Narimanov,1

    E-Print Network [OSTI]

    Tomsovic, Steve

    critical: if the wave function of the state at the chemical potential is poorly coupled to the leads heights, but are clearly seen in the correlation function or power spectrum. For nonzero temperature using tunneling contacts as a function of a gate voltage which tunes the electrostatic potential

  7. 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

  8. Midweek increase in U.S. summer rain and storm heights suggests air pollution

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    Midweek increase in U.S. summer rain and storm heights suggests air pollution invigorates air pollution suppresses cloud-drop coalescence and early rainout during the growth of thunderstorms explained by the difference in composition of aerosol pollution at that time. This ``weekend effect'' may

  9. 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 for a wind assessment campaign on the transformer/platform of Horns Rev, the world's largest offshore wind masts surrounding the wind farm. LiDAR and SoDAR observations of mean wind speed agree for the first

  10. Influence of Thermal Stratification on Wind Profiles for Heights up to 140 m

    E-Print Network [OSTI]

    Heinemann, Detlev

    Influence of Thermal Stratification on Wind Profiles for Heights up to 140 m Ulrich Focken, Detlev of the thermal stratification is well known normaly the neutral logarithmic wind profile is used, which leadsBruin for the thermal stratification is testet with measured data from the 200 m high met mast in Cabouw, Netherlands

  11. 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

  12. 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

  13. Annual Logging Symposium, June 16-20, 2012 SATURATION-HEIGHT AND INVASION CONSISTENT HYDRAULIC

    E-Print Network [OSTI]

    Torres-Verdín, Carlos

    on pore geometry, which relates to saturation-height modeling at a later stage in reservoir water saturation (Swi). The assumption is that the reservoir under study underwent hydrocarbon migration water method which is only applicable to reservoir zones that are at nearly irreducible water saturation

  14. 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

  15. Alcator C-Mod soft X-ray pulse height analysis system

    E-Print Network [OSTI]

    Gamboa, Eliseo (Eliseo J.)

    2007-01-01

    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 ...

  16. Short communication A new breaking wave height direct estimator from video imagery

    E-Print Network [OSTI]

    Short communication A new breaking wave height direct estimator from video imagery Rafael Almar a, laborious and limited to short term and localized field observations car- ried out on an energetic bathymetry through depth- inversion algorithms, where wave celerities or a proxy for wave breaking energy

  17. Maximum-Entropy Inference with a Programmable Annealer

    E-Print Network [OSTI]

    Chancellor, Nicholas; Vinci, Walter; Aeppli, Gabriel; Warburton, Paul A

    2015-01-01

    Optimisation problems in science and engineering typically involve finding the ground state (i.e. the minimum energy configuration) of a cost function with respect to many variables. If the variables are corrupted by noise then this approach maximises the likelihood that the solution found is correct. An alternative approach is to make use of prior statistical information about the noise in conjunction with Bayes's theorem. The maximum entropy solution to the problem then takes the form of a Boltzmann distribution over the ground and excited states of the cost function. Here we use a programmable Josephson junction array for the information decoding problem which we simulate as a random Ising model in a field. We show experimentally that maximum entropy decoding at finite temperature can in certain cases give competitive and even slightly better bit-error-rates than the maximum likelihood approach at zero temperature, confirming that useful information can be extracted from the excited states of the annealing...

  18. Effects of beef enhancement with non-meat ingredients, blade tenderization, and vacuum tumbling on quality attributes of four beef cuts stored in a high oxygen environment 

    E-Print Network [OSTI]

    Williams, Tracey Ann

    2005-02-17

    The objective of this study was to evaluate the effects of non-meat ingredients, blade tenderization and vacuum-tumbling on the textural, visual and sensory characteristics of steaks from Biceps femoris, Supraspinatus, ...

  19. Turbine blade platform film cooling with simulated stator-rotor purge flow with varied seal width and upstream wake with vortex 

    E-Print Network [OSTI]

    Blake, Sarah Anne

    2009-05-15

    The turbine blade platform can be protected from hot mainstream gases by injecting cooler air through the gap between stator and rotor. The effectiveness of this film cooling method depends on the geometry of the slot, the ...

  20. NGC2613, 3198, 6503, 7184: Case studies against `maximum' disks

    E-Print Network [OSTI]

    B. Fuchs

    1998-12-02

    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.

  1. Efficiency of autonomous soft nano-machines at maximum power

    E-Print Network [OSTI]

    Udo Seifert

    2010-11-11

    We consider nano-sized artificial or biological machines working in steady state enforced by imposing non-equilibrium concentrations of solutes or by applying external forces, torques or electric fields. For unicyclic and strongly coupled multicyclic machines, efficiency at maximum power is not bounded by the linear response value 1/2. For strong driving, it can even approach the thermodynamic limit 1. Quite generally, such machines fall in three different classes characterized, respectively, as "strong and efficient", "strong and inefficient", and "balanced". For weakly coupled multicyclic machines, efficiency at maximum power has lost any universality even in the linear response regime.

  2. History in the making : the construction of community memory and racial subjects in the Boyle Heights exhibition

    E-Print Network [OSTI]

    Chen, Su-Shuan

    2010-01-01

    The Boyle Heights Oral History Project: A Multiethnic andColorado Press, 2005. Oral History Transcripts conducted byand Daniel Widener. “A History of Black and Brown: Chicana/

  3. History in the making : the construction of community memory and racial subjects in the Boyle Heights exhibition

    E-Print Network [OSTI]

    Chen, Su-Shuan

    2010-01-01

    1997. Ngai, Mae. Impossible Subjects: Illegal Aliens and theof Community Memory and Racial Subjects in the Boyle Heightsof Community Memory and Racial Subjects in the Boyle Heights

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

    E-Print Network [OSTI]

    Nishino, Takafumi

    2012-01-01

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

  5. A model for prediction of the damage and effects of explosive projectiles on helicopter composite material rotor blades 

    E-Print Network [OSTI]

    Mikel, Tilden Newton

    1982-01-01

    Projectiles on Helicopter Composite Material Rotor Blades. (December 1982) Tilden Newton Nikel, B. S. , Texas AAM University; N . S . , Texas A&N University Chairman of Advisory Committee: Dr. Clarence L. Hough Jr. A number of damage models have been.... The funding for the ballistic tests conducted during this research was provided 'by Bell Helicopter Textron, Inc. , Fort cnorth, Texs s, TABLE OF CONTENTS Page ABSTRACT. . . . . ~ ~ ~ ~ ~ ~ ~ ~ ACKNOWLEDGMENT TABLE OF CONTENTS LIST OF TABLES. LIST...

  6. Distributed Computation of Maximum Lifetime Spanning Subgraphs in Sensor Networks

    E-Print Network [OSTI]

    ­ Helsinki University of Technology, P.O. Box 5400, FI-02015 TKK, Finland Harri.Haanpaa@tkk.fi, Andre levels to the battery-operated nodes so that under a uniform traffic load the net- work remains connected for a maximum length of time [2]. We consider the case where the nodes are non-mobile and the power levels, once

  7. Maximum power tracking control scheme for wind generator systems 

    E-Print Network [OSTI]

    Mena Lopez, Hugo Eduardo

    2009-05-15

    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...

  8. Tree-ring reconstruction of maximum and minimum temperatures

    E-Print Network [OSTI]

    -width (RW) and maximum density (MXD) series from treeline sites across Interior British Columbia. Multi- ple at these temperature-limited sites may be more closely related to Tmax than Tmean or Tmin; (3) recently reported in the relationships between ring-width (RW), maxi- mum latewood density (MXD) and May-August Tmean were observed

  9. Maximization of Recursive Utilities: A Dynamic Maximum Principle Approach

    E-Print Network [OSTI]

    Di Girolami, Cristina

    Maximization of Recursive Utilities: A Dynamic Maximum Principle Approach Wahid FAIDI LAMSIN, ENIT for a class of robust utility function introduced in Bordigoni, Matoussi et Schweizer (2005). Our method-investment strategy which is characterized as the unique solution of a forward-backward system. Key words : Utility

  10. The Evolution of Maximum Body Size of Terrestrial Mammals

    E-Print Network [OSTI]

    Brown, James H.

    The Evolution of Maximum Body Size of Terrestrial Mammals Felisa A. Smith,1 * Alison G. Boyer,2 the primary driver for the evolution of giant mammals was diversification to fill ecological niches extracted from the Paleobiology Database (12), using the range- through option for each interval of time. We

  11. Multiresolution Maximum Intensity Volume Rendering by Morphological Pyramids

    E-Print Network [OSTI]

    Roerdink, Jos B.T.M.

    to wavelet splatting, the main differences being that (i) linear summation of voxel values is replaced by maximum computation, and (ii) linear wavelet filters are replaced by (nonlinear) morphological filters. 1 on wavelets [4, 12, 18]. Recent methods for X-ray rendering include wavelet splatting [7, 8], which extends

  12. Multiresolution Maximum Intensity Volume Rendering by Morphological Adjunction Pyramids

    E-Print Network [OSTI]

    Roerdink, Jos B.T.M.

    to wavelet splatting, the main differences being that (i) linear summation of voxel values is replaced by maximum computation, and (ii) linear wavelet filters are replaced by (nonlinear) morphological filters wavelet splatting [11,12], which extends splatting [27] by using wavelets as reconstruction filters

  13. 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

  14. Maximum power tracking control scheme for wind generator systems 

    E-Print Network [OSTI]

    Mena Lopez, Hugo Eduardo

    2008-10-10

    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...

  15. "Maximum recycling of Material and Energy, Minimum of Landfilling"

    E-Print Network [OSTI]

    Columbia University

    lack of Waste-to-Energy capacity. #12;9 Austria As Germany, but Ban in force already in 2002. Landfill1 "Maximum recycling of Material and Energy, Minimum of Landfilling" "A Sustainable Solution" Håkan in "Recycling". "Waste-to-Energy" is now defined as Recycling, when energy efficiency is > 0,65 Prevention Reuse

  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. The Entropy of the Universe and the Maximum Entropy Production

    E-Print Network [OSTI]

    Lineweaver, Charles H.

    Chapter 22 The Entropy of the Universe and the Maximum Entropy Production Principle Charles H. Lineweaver Abstract If the universe had been born in a high entropy, equilibrium state, there would be no stars, no planets and no life. Thus, the initial low entropy of the universe is the fundamental reason

  18. What is a Hurricane? Tropical system with maximum sustained

    E-Print Network [OSTI]

    Meyers, Steven D.

    Hurricane 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 as a tropical cyclone. #12;Hurricanes in Florida · 1851-2004 Florida's Hurricane Total: 110 Southwest Florida

  19. Exit blade geometry and part-load performance of small axial flow propeller turbines: An experimental investigation

    SciTech Connect (OSTI)

    Singh, Punit; Nestmann, Franz

    2010-09-15

    A detailed experimental investigation of the effects of exit blade geometry on the part-load performance of low-head, axial flow propeller turbines is presented. Even as these turbines find important applications in small-scale energy generation using micro-hydro, the relationship between the layout of blade profile, geometry and turbine performance continues to be poorly characterized. The experimental results presented here help understand the relationship between exit tip angle, discharge through the turbine, shaft power, and efficiency. The modification was implemented on two different propeller runners and it was found that the power and efficiency gains from decreasing the exit tip angle could be explained by a theoretical model presented here based on classical theory of turbomachines. In particular, the focus is on the behaviour of internal parameters like the runner loss coefficient, relative flow angle at exit, mean axial flow velocity and net tangential flow velocity. The study concluded that the effects of exit tip modification were significant. The introspective discussion on the theoretical model's limitation and test facility suggests wider and continued experimentation pertaining to the internal parameters like inlet vortex profile and exit swirl profile. It also recommends thorough validation of the model and its improvement so that it can be made capable for accurate characterization of blade geometric effects. (author)

  20. Transient growth mechanisms of low Reynolds number flow over a low-pressure turbine blade

    E-Print Network [OSTI]

    Sharma, AS; Sherwin, SJ; Theofilis, V; 10.1007/s00162-010-0183-9

    2013-01-01

    A direct transient growth analysis for three-dimensional perturbations to flow past a periodic array of T-106/300 low-pressure turbine fan blades is presented. The methodology is based on a singular value decomposition of the flow evolution operator, linearised about a steady or periodic base flow. This analysis yields the optimal growth modes. Previous work on global mode stability analysis of this flow geometry showed the flow is asymptotically stable, indicating a non-modal explanation of transition may be more appropriate. The present work extends previous investigations into the transient growth around a steady base flow, to higher Reynolds numbers and periodic base flows. It is found that the notable transient growth of the optimal modes suggests a plausible route to transition in comparison to modal growth for this configuration. The spatial extent and localisation of the optimal modes is examined and possible physical triggering mechanisms are discussed. It is found that for longer times and longer sp...

  1. Progress Toward Luminescence-Based VAATE Turbine Blade And Vane Temperature Measurement

    SciTech Connect (OSTI)

    Jenkins, Tom P.; Allison, Stephen W; Eldridge, Jeffrey I.; Niska, R. H.; Condevaux, J. J.; Wolfe, Doug E.; Jordan, Eric H.; Heeg, Bauke

    2012-01-01

    Progress towards fielding luminescence-based temperature measurements for the Versatile Affordable Advanced Turbine Engine (VAATE) program is described. The near term programmatic objective is to monitor turbine vane temperatures and health by luminescence from a rare-earth doped thermal barrier coating (TBC), or from a thermographic phosphor layer coated onto a TBC. The first goal is to establish the temperature measurement capability to 1300 C with 1 percent uncertainty in a test engine. An eventual goal is to address rotating turbine blades in an F135 engine. The project consists of four phases, of which the first two have been completed and are described in this paper. The first phase involved laser heating of a 2.54-cm-diameter test sample, coated with a TBC and a thermographic phosphor layer, to produce a thermal gradient across the TBC layer similar to that expected in a turbine engine. Phosphor temperatures correlated well with those measured by long wavelength pyrometry. In the second phase, 10x10- cm coupons were exposed to a jet fuel flame at a burner rig facility. The thermographic phosphor/TBC combination survived the aggressive flame and high exhaust gas velocity, even though the metal substrate melted. Reliable temperature measurements were made up to about 1400 C using YAG:Dy as the thermographic phosphor. In addition, temperature measurements using YAG:Tm showed very desirable background radiation suppression.

  2. Shape reconstruction and height fluctuations of red blood cells using defocusing microscopy

    E-Print Network [OSTI]

    Siman, L; Amaral, F T; Agero, U; Mesquita, O N

    2014-01-01

    In this paper the bright-field defocusing microscopy (DM) technique is presented. DM is able to obtain quantitative information of each plane/surface of pure phase objects, as live unlabeled cells, and its application to red blood cells (RBCs) is demonstrated. Based on contrast, simple methods to obtain thickness profile and three dimensional (3D) total reconstruction of RBCs are proposed and the actual height profiles of upper and lower surface-membranes (lipid bilayer$/$cytoskeleton) of discocyte and stomatocyte red cells are presented as examples. In addition, using the mean square contrast fluctuation and modeling the RBC membranes fluctuations spectra as dependent of a bending modulus $(\\kappa_c)$, a surface tension $(\\sigma)$ and a confining potential $(\\gamma)$ term, slowly varying quantities along the cell radius, a genetic algorithm (GA) is used and the radial height fluctuations of each surface-membrane are accessed, separately. The radial behaviors of $\\kappa_c$, $\\sigma$ and $\\gamma$ are also obta...

  3. Height control of self-assembled quantum dots by strain engineering during capping

    SciTech Connect (OSTI)

    Grossi, D. F., E-mail: d.grossi@tue.nl; Koenraad, P. M. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven (Netherlands); Smereka, P. [Department of Mathematics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Keizer, J. G. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven (Netherlands); Australian Research Council Centre of Excellence for Quantum Computation and Communications, School of Physics, University of New South Wales, Sydney 2052 (Australia); Ulloa, J. M. [Institute for Systems based on Optoelectronics and Microtechnology (ISOM), Universidad Politecnica de Madrid, Avenida Complutense 30, 28040 Madrid (Spain)

    2014-10-06

    Strain engineering during the capping of III-V quantum dots has been explored as a means to control the height of strained self-assembled quantum dots. Results of Kinetic Monte Carlo simulations are confronted with cross-sectional Scanning Tunnel Microscopy (STM) measurements performed on InAs quantum dots grown by molecular beam epitaxy. We studied InAs quantum dots that are capped by In{sub x}Ga{sub (1?x)}As layers of different indium compositions. Both from our realistic 3D kinetic Monte Carlo simulations and the X-STM measurements on real samples, a trend in the height of the capped quantum dot is found as a function of the lattice mismatch between the quantum dot material and the capping layer. Results obtained on additional material combinations show a generic role of the elastic energy in the control of the quantum dot morphology by strain engineering during capping.

  4. Analysis of the classical pseudo-3D model for hydraulic fracture with equilibrium height growth across stress barriers

    E-Print Network [OSTI]

    Peirce, Anthony

    Analysis of the classical pseudo-3D model for hydraulic fracture with equilibrium height growth t This paper deals with the so-called ``pseudo three-dimensional'' (P3D) model for a hydraulic fracture of the length, height, and aperture of the hydraulic fracture, in contrast to the numerical formulations adopted

  5. HIGHER PICARD VARIETIES AND THE HEIGHT PAIRING KLAUS KU"NNEMANN

    E-Print Network [OSTI]

    defined under suitable assumptions height pai* *rings (1) XK: CHp(XK )0Q x CHd+1-p of the Hodge index theorem should hold for the pairing (1). We denote by Ap(XK )Q the subgroup of CHp(XK )0Q of this note is to show that these theorems hold for the subquotients Bp(AK )Q of CHp(AK )0Q . The hard

  6. Chamberlain Heights Redevelopment: A Large Scale, Cold Climate Study of Affordable Housing Retrofits

    SciTech Connect (OSTI)

    Donnelly, K.; Mahle, M.

    2012-03-01

    The City of Meriden Housing Authority (MHA) collaborated with affordable housing developer Jonathon Rose Companies (JRC) to complete a gut renovation of 124 residential units in the Chamberlain Heights retrofit project. The affordable housing community is made up of 36 buildings in duplex and quad configurations located on 22 acres within two miles of downtown Meriden, CT. The final post-retrofit analysis showed 40%-45% source energy savings over the existing pre-retrofit conditions.

  7. Chamberlain Heights Redevelopment: A Large Scale, Cold Climate Study of Affordable Housing Retrofits

    SciTech Connect (OSTI)

    Donnelly, K.; Mahle, M.

    2012-03-01

    The City of Meriden Housing Authority (MHA) collaborated with affordable housing developer Jonathon Rose Companies (JRC) to complete a gut renovation of 124 residential units in the Chamberlain Heights retrofit project. The affordable housing community is made up of 36 buildings in duplex and quad configurations located on 22 acres within two miles of downtown Meriden, CT. The final post-retrofit analysis showed 40-45% source energy savings over the existing pre-retrofit conditions.

  8. Maximum Entropy Principle and the Higgs Boson Mass

    E-Print Network [OSTI]

    Alves, Alexandre; da Silva, Roberto

    2014-01-01

    A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.

  9. Maximum Entropy Principle and the Higgs Boson Mass

    E-Print Network [OSTI]

    Alexandre Alves; Alex G. Dias; Roberto da Silva

    2014-11-18

    A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.

  10. The Prediction of the Maximum Modes of Decay of Mesons

    E-Print Network [OSTI]

    Ramanna, R

    1999-01-01

    In an earlier work, several properties of fundamental particles were brought together by a simple equation based on continuity and discreteness. It is shown here, that the maximum modes of decay of all fundamental particles can also be predicted without any arbitrary parameters. The method used is to break up the mean lifetimes of particles to obtain the maximum modes of decay. This is done by using a binary expansion of $\\hbar/MT$ where M is the mass of the particle and T is the mean lifetime. The agreements between that obtained from theory and experiment are remarkable. The ordering of the flavours plays an important part in understanding the reasons for this agreement. It is shown that the Zeno effect in Quantum mechanics is connected with use of the binary series.

  11. The Prediction of the Maximum Modes of Decay of Mesons

    E-Print Network [OSTI]

    Raja Ramanna

    1999-04-27

    In an earlier work, several properties of fundamental particles were brought together by a simple equation based on continuity and discreteness. It is shown here, that the maximum modes of decay of all fundamental particles can also be predicted without any arbitrary parameters. The method used is to break up the mean lifetimes of particles to obtain the maximum modes of decay. This is done by using a binary expansion of $\\hbar/MT$ where M is the mass of the particle and T is the mean lifetime. The agreements between that obtained from theory and experiment are remarkable. The ordering of the flavours plays an important part in understanding the reasons for this agreement. It is shown that the Zeno effect in Quantum mechanics is connected with use of the binary series.

  12. Maximum entropy method for reconstruction of the CMB images

    E-Print Network [OSTI]

    A. T. Bajkova

    2002-05-21

    We propose a new approach for the accurate reconstruction of cosmic microwave background distributions from observations containing in addition to the primary fluctuations the radiation from unresolved extragalactic point sources and pixel noise. The approach uses some effective realizations of the well-known maximum entropy method and principally takes into account {\\it a priori} information about finiteness and spherical symmetry of the power spectrum of the CMB satisfying the Gaussian statistics.

  13. Maximum-Entropy Inference with a Programmable Annealer

    E-Print Network [OSTI]

    Nicholas Chancellor; Szilard Szoke; Walter Vinci; Gabriel Aeppli; Paul A. Warburton

    2015-06-26

    Optimisation problems in science and engineering typically involve finding the ground state (i.e. the minimum energy configuration) of a cost function with respect to many variables. If the variables are corrupted by noise then this approach maximises the likelihood that the solution found is correct. An alternative approach is to make use of prior statistical information about the noise in conjunction with Bayes's theorem. The maximum entropy solution to the problem then takes the form of a Boltzmann distribution over the ground and excited states of the cost function. Here we use a programmable Josephson junction array for the information decoding problem which we simulate as a random Ising model in a field. We show experimentally that maximum entropy decoding at finite temperature can in certain cases give competitive and even slightly better bit-error-rates than the maximum likelihood approach at zero temperature, confirming that useful information can be extracted from the excited states of the annealing device. Furthermore we introduce a microscopic bit-by-bit analytical method which is agnostic to the specific application and use it to show that the annealing device samples from a highly Boltzmann-like distribution. Machines of this kind are therefore candidates for use in a wide variety of machine learning applications which exploit maximum entropy inference, including natural language processing and image recognition. We further show that the limiting factor for performance in our experiments is likely to be control errors rather than failure to reach equilibrium. Our work also provides a method for determining if a system is in equilibrium which can be easily generalized. We discuss possible applications of this method to spin glasses and probing the performance of the quantum annealing algorithm.

  14. Max '91: flare research at the next solar maximum

    SciTech Connect (OSTI)

    Dennis, B.; Canfield, R.; Bruner, M.; Emslie, G.; Hildner, E.; Hudson, H.; Hurford, G.; Lin, R.; Novick, R.; Tarbell, T.

    1988-01-01

    To address the central scientific questions surrounding solar flares, coordinated observations of electromagnetic radiation and energetic particles must be made from spacecraft, balloons, rockets, and ground-based observatories. A program to enhance capabilities in these areas in preparation for the next solar maximum in 1991 is recommended. The major scientific issues are described, and required observations and coordination of observations and analyses are detailed. A program plan and conceptual budgets are provided.

  15. Maximum total organic carbon limit for DWPF melter feed

    SciTech Connect (OSTI)

    Choi, A.S.

    1995-03-13

    DWPF recently decided to control the potential flammability of melter off-gas by limiting the total carbon content in the melter feed and maintaining adequate conditions for combustion in the melter plenum. With this new strategy, all the LFL analyzers and associated interlocks and alarms were removed from both the primary and backup melter off-gas systems. Subsequently, D. Iverson of DWPF- T{ampersand}E requested that SRTC determine the maximum allowable total organic carbon (TOC) content in the melter feed which can be implemented as part of the Process Requirements for melter feed preparation (PR-S04). The maximum TOC limit thus determined in this study was about 24,000 ppm on an aqueous slurry basis. At the TOC levels below this, the peak concentration of combustible components in the quenched off-gas will not exceed 60 percent of the LFL during off-gas surges of magnitudes up to three times nominal, provided that the melter plenum temperature and the air purge rate to the BUFC are monitored and controlled above 650 degrees C and 220 lb/hr, respectively. Appropriate interlocks should discontinue the feeding when one or both of these conditions are not met. Both the magnitude and duration of an off-gas surge have a major impact on the maximum TOC limit, since they directly affect the melter plenum temperature and combustion. Although the data obtained during recent DWPF melter startup tests showed that the peak magnitude of a surge can be greater than three times nominal, the observed duration was considerably shorter, on the order of several seconds. The long surge duration assumed in this study has a greater impact on the plenum temperature than the peak magnitude, thus making the maximum TOC estimate conservative. Two models were used to make the necessary calculations to determine the TOC limit.

  16. Maximum Entry and Mandatory Separation Ages for Certain Security Employees

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-10-11

    The policy establishes the DOE policy on maximum entry and mandatory separation ages for primary or secondary positions covered under special statutory retirement provisions and for those employees whose primary duties are the protection of officials of the United States against threats to personal safety or the investigation, apprehension, and detention of individuals suspected or convicted of offenses against the criminal laws of the United States. Admin Chg 1, dated 12-1-11, supersedes DOE P 310.1.

  17. Maximum patch method for directional dark matter detection

    SciTech Connect (OSTI)

    Henderson, Shawn; Monroe, Jocelyn; Fisher, Peter [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Laboratory for Nuclear Science, MIT Kavli Institute for Astrophysics and Space Research, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2008-07-01

    Present and planned dark matter detection experiments search for WIMP-induced nuclear recoils in poorly known background conditions. In this environment, the maximum gap statistical method provides a way of setting more sensitive cross section upper limits by incorporating known signal information. We give a recipe for the numerical calculation of upper limits for planned directional dark matter detection experiments, that will measure both recoil energy and angle, based on the gaps between events in two-dimensional phase space.

  18. Maximum entanglement in squeezed boson and fermion states

    SciTech Connect (OSTI)

    Khanna, F. C. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Malbouisson, J. M. C. [Instituto de Fisica, Universidade Federal da Bahia, 40210-340, Salvador, BA (Brazil); Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Santana, A. E. [Instituto de Fisica, Universidade de Brasilia, 70910-900, Brasilia, DF (Brazil); Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Santos, E. S. [Centro Federal de Educacao Tecnologica da Bahia, 40030-010, Salvador, BA (Brazil)

    2007-08-15

    A class of squeezed boson and fermion states is studied with particular emphasis on the nature of entanglement. We first investigate the case of bosons, considering two-mode squeezed states. Then we construct the fermion version to show that such states are maximum entangled, for both bosons and fermions. To achieve these results, we demonstrate some relations involving squeezed boson states. The generalization to the case of fermions is made by using Grassmann variables.

  19. PNNL: A Supervised Maximum Entropy Approach to Word Sense Disambiguation

    SciTech Connect (OSTI)

    Tratz, Stephen C.; Sanfilippo, Antonio P.; Gregory, Michelle L.; Chappell, Alan R.; Posse, Christian; Whitney, Paul D.

    2007-06-23

    In this paper, we described the PNNL Word Sense Disambiguation system as applied to the English All-Word task in Se-mEval 2007. We use a supervised learning approach, employing a large number of features and using Information Gain for dimension reduction. Our Maximum Entropy approach combined with a rich set of features produced results that are significantly better than baseline and are the highest F-score for the fined-grained English All-Words subtask.

  20. Maximum Power Transfer Tracking for a Photovoltaic-Supercapacitor Energy System

    E-Print Network [OSTI]

    Pedram, Massoud

    Maximum Power Transfer Tracking for a Photovoltaic-Supercapacitor Energy System Younghyun KimPconverter Ppv Pcharge Varying Pleak PV array Supercapacitor Figure 1: Photovoltaic-supercapacitor energy system Keywords Maximum power transfer tracking, Photovoltaic, Supercapacitor 1. INTRODUCTION Maximum energy

  1. Active Aerodynamic Blade Distributed Flap Control Design Procedure for Load Reduction on the UpWind

    E-Print Network [OSTI]

    vector vmax maximum sensor output vector Technical Staff, Energy Systems Analysis/Wind and Water Power 5MW Wind Turbine David G. Wilson , Brian R. Resor , Dale E. Berg Sandia National Laboratories, P that is employed for distributed control system design for large wind turbine load reduction applications

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

    SciTech Connect (OSTI)

    Janet M Twomey, PhD

    2010-04-30

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

  3. Maximum likelihood method for cross-correlations with astrophysical sources

    SciTech Connect (OSTI)

    Jansson, Ronnie; Farrar, Glennys R, E-mail: rj486@nyu.edu, E-mail: gf25@nyu.edu [Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY 10003 (United States)

    2008-06-15

    We generalize the maximum likelihood-type method used to study cross-correlations between a catalog of candidate astrophysical sources and ultrahigh energy cosmic rays (UHECRs), to allow for differing source luminosities. The new method is applicable to any sparse dataset such as UHE gamma rays or astrophysical neutrinos. Performance of the original and generalized techniques is evaluated in simulations of various scenarios. Applying the new technique to data, we find an excess correlation of about nine events between HiRes UHECRs and known BLLacs, with a 6 Multiplication-Sign 10{sup -5} probability of such a correlation arising by chance.

  4. Generalized Maximum Likelihood Method for Ultrahigh Energy Cosmic Rays

    E-Print Network [OSTI]

    Glennys R. Farrar

    2008-10-01

    The Maximum Likelihood Method is generalized to include effects important for UHECR applications. The new approach can incorporate source distance constraints implied by the observed CR energy and can allow for energy uncertainties, possible deflection in magnetic fields, multiple source types, and a spectrum of CR composition. It can be efficiently implemented and does not require the unphysical "isotropic" assumption for unidentified sources. The approach optimizes the utility of UHECR data to discriminate between source classes and can help constrain galactic and extragalactic magnetic fields. Aspects of the method are directly applicable in other contexts, such as TeV gamma ray astrophysics.

  5. Maximum Likelihood Method for Cross Correlations with Astrophysical Sources

    E-Print Network [OSTI]

    Ronnie Jansson; Glennys R. Farrar

    2008-06-18

    We generalize the Maximum Likelihood-type method used to study cross correlations between a catalog of candidate astrophysical sources and Ultrahigh Energy Cosmic Rays (UHECRs), to allow for differing source luminosities. The new method is applicable to any sparse data set such as UHE gamma rays or astrophysical neutrinos. Performance of the original and generalized techniques is evaluated in simulations of various scenarios. Applying the new technique to data, we find an excess correlation of about 9 events between HiRes UHECRs and known BLLacs, with a 6*10^-5 probability of such a correlation arising by chance.

  6. 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

    2009-01-01

    stream_source_info TR-341 Bacteria TMDL Task Force Report Draft Four 6.4.07.pdf.txt stream_content_type text/plain stream_size 344770 Content-Encoding ISO-8859-1 stream_name TR-341 Bacteria TMDL Task Force Report Draft Four 6....4.07.pdf.txt Content-Type text/plain; charset=ISO-8859-1 TR-341 2009 Bacteria Total Maximum Daily Load Task Force Final Report By C. Allan Jones and Kevin Wagner, Texas Water Resources...

  7. Maximum Tension: with and without a cosmological constant

    E-Print Network [OSTI]

    Barrow, John D.; Gibbons, G. W.

    2014-12-04

    and the absence of any speed limit for information transmission. This unusual Newtonian behaviour has no general relativistic counterpart: two particles of mass M whose centres approach closer than d = 4GM=c2 will ?nd themselves inside a black hole horizon... , Ann. d Physik 11, 69 (1900); English translation in M. Planck, 1959, The Theory of Heat Radiation, transl. M. Masius, Dover, New York (1959). 11 Schiller C., 1997-2004, Maximum force a simple principle encompassing general relativity in C. Schiller...

  8. Better Nonlinear Models from Noisy Data: Attractors with Maximum Likelihood

    E-Print Network [OSTI]

    Patrick E. McSharry; Leonard A. Smith

    1999-11-30

    A new approach to nonlinear modelling is presented which, by incorporating the global behaviour of the model, lifts shortcomings of both least squares and total least squares parameter estimates. Although ubiquitous in practice, a least squares approach is fundamentally flawed in that it assumes independent, normally distributed (IND) forecast errors: nonlinear models will not yield IND errors even if the noise is IND. A new cost function is obtained via the maximum likelihood principle; superior results are illustrated both for small data sets and infinitely long data streams.

  9. The Maximum Value Method. (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)FeedbackProperties ofThe Maximum Value Method. Citation Details

  10. Computing dynamic height from temperature profiles north of 30N in the Pacific Ocean 

    E-Print Network [OSTI]

    O'Brien, Anthony

    1978-01-01

    fronts and their relation to the wind and energy flux fields. J. Geophys. Res. , 5, 557 ? 571. Sverdrup, H, U. , M. W. Johnson, and R. H. Fleming, 1942: The Oceans Their Phys7cs, Chemistry and General Biology. Prentice Hall. Stommel, H. S. , 1947... 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 1fASTER OF SCIENCF. May 1978...

  11. Mach number correlation for a two-dimensional helicopter rotor-blade analysis in the tip region 

    E-Print Network [OSTI]

    Schillings, John Joseph

    1983-01-01

    -'7. The value of corrected Mach number (Hc) is defined as Mc =M+5M The delta Mach number required is shown as a function of blade 31 Table 4 Summary of Parameters for Flight Condition Azimuth MTTP r/R Mc Cn 90 . 846 . 750 . 682 . 846 . 757 . 910 . 787... . 955 . 8'16 . 970 . 826 . 990 . 839 . 0 . 0 -. 020 -. 040 -. 050 ? . 110 . 682 . 321 . 757 . 195 , 767 . 155 . 776 . 166 . 776 . 099 . 729 ~ 077 Table 5 Summary of Parameters for Flight Condition Azimuth MTip r/R Mc Cn 30 60 90 120...

  12. Thermodynamics of Maximum Transition Entropy for Quantum Assemblies

    E-Print Network [OSTI]

    David M. Rogers

    2015-03-27

    This work presents a general unifying theoretical framework for quantum non-equilibrium systems. It is based on a re-statement of the dynamical problem as one of inferring the distribution of collision events that move a system toward thermal equilibrium from an arbitrary starting distribution. Using a form based on maximum entropy for this transition distribution leads to a statistical description of open quantum systems with strong parallels to the conventional, maximum-entropy, equilibrium thermostatics. A precise form of the second law of thermodynamics can be stated for this dynamics at every time-point in a trajectory. Numerical results are presented for low-dimensional systems interacting with cavity fields. The dynamics and stationary state are compared to a reference model of a weakly coupled oscillator plus cavity supersystem thermostatted by periodic partial measurements. Despite the absence of an explicit cavity in the present model of open quantum dynamics, both the relaxation rates and stationary state properties closely match the reference. Additionally, the time-course of energy exchange and entropy increase is given throughout an entire measurement process for a single spin system. The results show the process to be capable of initially absorbing heat when starting from a superposition state, but not from an isotropic distribution. Based on these results, it is argued that logical inference in the presence of environmental noise is sufficient to resolve the paradox of wavefunction collapse.

  13. Investigation of bit patterned media, thermal flying height control sliders and heat assisted magnetic recording in hard disk drives

    E-Print Network [OSTI]

    Zheng, Hao

    2011-01-01

    flying head slider bearings in magnetic hard disk drives,”height control and air bearing cooling of magnetic recordingCenter for Magnetic Recording Research (CMRR) an air bearing

  14. Estimate of Maximum Underground Working Gas Storage Capacity in the United States

    Reports and Publications (EIA)

    2006-01-01

    This report examines the aggregate maximum capacity for U.S. natural gas storage. Although the concept of maximum capacity seems quite straightforward, there are numerous issues that preclude the determination of a definitive maximum volume. The report presents three alternative estimates for maximum capacity, indicating appropriate caveats for each.

  15. H. J. Sutherland and John F. Mandell, "Application of the U.S. High Cycle Fatigue Data Base to Wind Turbine Blade Lifetime Predictions," Energy Week 1996, Book VIII: Wind

    E-Print Network [OSTI]

    to Wind Turbine Blade Lifetime Predictions," Energy Week 1996, Book VIII: Wind Energy, ASME, January PREDICTIONS Herbert J. Sutherland Wind Energy Technology Sandia National Laboratories Albuquerque, NM 87185-February, 1996, pp. 85-92. APPLICATION OF THE U.S. HIGH CYCLE FATIGUE DATA BASE TO WIND TURBINE BLADE LIFETIME

  16. J.H. Gieske, M.A. Rumsey, "Nondestructive Evaluation (Nde) Of Composite/Metal Bond Interface Of A Wind Turbine Blade Using An Acousto-Ultrasonic Technique," 1997 ASME Wind Energy

    E-Print Network [OSTI]

    Of A Wind Turbine Blade Using An Acousto-Ultrasonic Technique," 1997 ASME Wind Energy Symposium, AIAA/ASME, 1997, pp. 249-254. NONDESTRUCTIVE EVALUATION (NDE) OF COMPOSITE/METAL BOND INTERFACE OF A WIND TURBINE insert and the fiber glass epoxy composite of a wind turbine blade. Data was generated manually as well

  17. A LIDAR-based crop height measurement system for Miscanthus giganteus Lei Zhang, Tony E. Grift

    E-Print Network [OSTI]

    G stem densities. The results showed an average error of 5.08% with a maximum error of 8% and a minimum of bioenergy crop performance. Field crops such as corn and soybean are harvested for their seeds, and various flow measurements. However, in the case of bioenergy crops, the complete above ground plant

  18. Reduction in maximum time uncertainty of paired time signals

    DOE Patents [OSTI]

    Theodosiou, G.E.; Dawson, J.W.

    1981-02-11

    Reduction in the maximum time uncertainty (t/sub max/ - t/sub min/) of a series of paired time signals t/sub 1/ and t/sub 2/ varying between two input terminals and representative of a series of single events where t/sub 1/ less than or equal to t/sub 2/ and t/sub 1/ + t/sub 2/ equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t/sub min/) of the first signal t/sub 1/ closer to t/sub max/ and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20 to 800.

  19. Improved Maximum Entropy Analysis with an Extended Search Space

    E-Print Network [OSTI]

    Alexander Rothkopf

    2013-01-07

    The standard implementation of the Maximum Entropy Method (MEM) follows Bryan and deploys a Singular Value Decomposition (SVD) to limit the dimensionality of the underlying solution space apriori. Here we present arguments based on the shape of the SVD basis functions and numerical evidence from a mock data analysis, which show that the correct Bayesian solution is not in general recovered with this approach. As a remedy we propose to extend the search basis systematically, which will eventually recover the full solution space and the correct solution. In order to adequately approach problems where an exponentially damped kernel is used, we provide an open-source implementation, using the C/C++ language that utilizes high precision arithmetic adjustable at run-time. The LBFGS algorithm is included in the code in order to attack problems without the need to resort to a particular search space restriction.

  20. Efficiency at maximum power of a chemical engine

    E-Print Network [OSTI]

    Hooyberghs, Hans; Salazar, Alberto; Indekeu, Joseph O; Broeck, Christian Van den

    2013-01-01

    A cyclically operating chemical engine is considered that converts chemical energy into mechanical work. The working fluid is a gas of finite-sized spherical particles interacting through elastic hard collisions. For a generic transport law for particle uptake and release, the efficiency at maximum power $\\eta$ takes the form 1/2+c\\Delta \\mu + O(\\Delta \\mu^2), with 1/2 a universal constant and $\\Delta \\mu$ the chemical potential difference between the particle reservoirs. The linear coefficient c is zero for engines featuring a so-called left/right symmetry or particle fluxes that are antisymmetric in the applied chemical potential difference. Remarkably, the leading constant in $\\eta$ is non-universal with respect to an exceptional modification of the transport law. For a nonlinear transport model we obtain \\eta = 1/(\\theta +1), with \\theta >0 the power of $\\Delta \\mu$ in the transport equation