Wind Tunnel Testing Facilities

Data.gov (United States)

Federal Laboratory Consortium — NASA Ames Research Center is pleased to offer the services of our premier wind tunnel facilities that have a broad range of proven testing capabilities to customers...

Cooperative field test program for wind systems

Energy Technology Data Exchange (ETDEWEB)

Bollmeier, W.S. II; Dodge, D.M.

1992-03-01

The objectives of the Federal Wind Energy Program, managed by the US Department of Energy (DOE), are (1) to assist industry and utilities in achieving a multi-regional US market penetration of wind systems, and (2) to establish the United States as the world leader in the development of advanced wind turbine technology. In 1984, the program conducted a series of planning workshops with representatives from the wind energy industry to obtain input on the Five-Year Research Plan then being prepared by DOE. One specific suggestion that came out of these meetings was that the federal program should conduct cooperative research tests with industry to enhance the technology transfer process. It was also felt that the active involvement of industry in DOE-funded research would improve the state of the art of wind turbine technology. DOE established the Cooperative Field Test Program (CFTP) in response to that suggestion. This program was one of the first in DOE to feature joint industry-government research test teams working toward common objectives.

Wind tunnel tests of a free yawing downwind wind turbine

DEFF Research Database (Denmark)

Verelst, David Robert; Larsen, Torben J.; van Wingerden, J.W.

2012-01-01

During February and April 2012 a series of wind tunnel tests were performed at the TU Delft Open Jet Facility (OJF) with a three bladed downwind wind turbine and a rotor radius of 0.8 meters. The setup includes an off the shelf three bladed hub, nacelle and generator on which relatively flexible ...... in free yawing conditions. Further, the effect of the tower shadow passage on the blade flapwise strain measurement is evaluated. Finally, data from the experiment is compared with preliminary simulations using DTU Wind Energy's aeroelastic simulation program HAWC2....... blades are mounted. The tower support structure has free yawing capabilities provided at the tower base. A short overview on the technical details of the experiment is provided as well as a brief summary of the design process. The discussed test cases show that the turbine is stable while operating...

Wind Turbine Generator System Safety and Function Test Report for the Southwest Windpower H40 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

van Dam, J.; Link, H.; Meadors, M.; Bianchi, J.

2002-06-01

The objective of this test was to evaluate the safety and function characteristics of the Whisper H40 wind turbine. The general requirements of wind turbine safety and function tests are defined in the IEC standard WT01. The testing was conducted in accordance with the National Wind Technology Center (NWTC) Quality Assurance System, including the NWTC Certification Team Certification Quality Manual and the NWTC Certification Team General Quality Manual for the Testing of Wind Turbines, as well as subordinate documents. This safety and function test was performed as part of the U.S. Department of Energy's Field Verification Program for small wind turbines.

Duration Test Report for the Ventera VT10 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

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

2013-06-01

This project was established to help reduce the barriers of wind energy expansion by providing independent testing results for small wind turbines. Five turbines were tested at the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL) as a part of round one of this project. Duration testing is one of up to five tests that may be performed on the turbines, including power performance, safety and function, noise, and power quality. Test results will provide manufacturers with reports that can be used to fulfill part of the requirements for small wind turbine certification. The test equipment included a grid-connected Ventera Energy Corporation VT10 wind turbine mounted on an 18.3-m (60-ft) self-supporting lattice tower manufactured by Rohn.

Power Performance Test Report for the SWIFT Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Mendoza, I.; Hur, J.

2012-12-01

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

Safety and Function Test Report for the SWIFT Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Mendoza, I.; Hur, J.

2013-01-01

This test was conducted as part of the U.S. Department of Energy's (DOE) Independent Testing project. This project was established to help reduce the barriers of wind energy expansion by providing independent testing results for small turbines. Three turbines where selected for testing at the National Wind Technology Center (NWTC) as a part of round two of the Small Wind Turbine Independent Testing project. Safety and Function testing is one of up to 5 tests that may be performed on the turbines. Other tests include power performance, duration, noise, and power quality. The results of the testing will provide the manufacturers with reports that may be used for small wind turbine certification.

The Great Plains Wind Power Test Facility

Energy Technology Data Exchange (ETDEWEB)

Schroeder, John [Texas Tech Univ., Lubbock, TX (United States)

2014-01-30

This multi-year, multi-faceted project was focused on the continued development of a nationally-recognized facility for the testing, characterization, and improvement of grid-connected wind turbines, integrated wind-water desalination systems, and related educational and outreach topics. The project involved numerous faculty and graduate students from various engineering departments, as well as others from the departments of Geosciences (in particular the Atmospheric Science Group) and Economics. It was organized through the National Wind Institute (NWI), which serves as an intellectual hub for interdisciplinary and transdisciplinary research, commercialization and education related to wind science, wind energy, wind engineering and wind hazard mitigation at Texas Tech University (TTU). Largely executed by an academic based team, the project resulted in approximately 38 peer-reviewed publications, 99 conference presentations, the development/expansion of several experimental facilities, and two provisional patents.

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-11-01

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

Clemson University Wind Turbine Drivetrain Test Facility

Energy Technology Data Exchange (ETDEWEB)

Tuten, James Maner [Clemson Univ., SC (United States); Haque, Imtiaz [Clemson Univ., SC (United States); Rigas, Nikolaos [Clemson Univ., SC (United States)

2016-03-30

In November of 2009, Clemson University was awarded a competitive grant from the U.S. Department of Energy to design, build and operate a facility for full-scale, highly accelerated mechanical testing of next-generation wind turbine drivetrain technologies. The primary goal of the project was to design, construct, commission, and operate a state-of-the-art sustainable facility that permits full-scale highly accelerated testing of advanced drivetrain systems for large wind turbines. The secondary goal was to meet the objectives of the American Recovery and Reinvestment Act of 2009, especially in job creation, and provide a positive impact on economically distressed areas in the United States, and preservation and economic recovery in an expeditious manner. The project was executed according to a managed cooperative agreement with the Department of Energy and was an extraordinary success. The resultant new facility is located in North Charleston, SC, providing easy transportation access by rail, road or ship and operates on an open access model such that it is available to the U.S. Wind Industry for research, analysis, and evaluation activities. The 72 m by 97 m facility features two mechanical dynamometer test bays for evaluating the torque and blade dynamic forces experienced by the rotors of wind turbine drivetrains. The dynamometers are rated at 7.5 MW and 15 MW of low speed shaft power and are configured as independent test areas capable of simultaneous operation. All six degrees of freedom, three linear and three rotational, for blade and rotor dynamics are replicated through the combination of a drive motor, speed reduction gearbox and a controllable hydraulic load application unit (LAU). This new LAU setup readily supports accelerated lifetime mechanical testing and load analysis for the entire drivetrain system of the nacelle and easily simulates a wide variety of realistic operating scenarios in a controlled laboratory environment. The development of these

Fatigue Test Design: Scenarios for Biaxial Fatigue Testing of a 60-Meter Wind Turbine Blade

Energy Technology Data Exchange (ETDEWEB)

Post, Nathan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-07-01

Current practice in commercial certification of wind turbine blades is to perform separate flap and lead-lag fatigue tests. The National Renewable Energy Laboratory has been researching and evaluating biaxial fatigue testing techniques and demonstrating various options, typically on smaller-scale test articles at the National Wind Technology Center. This report evaluates some of these biaxial fatigue options in the context of application to a multimegawatt blade certification test program at the Wind Technology Testing Center in Charlestown, Massachusetts.

Wind Turbine Generator System Acoustic Noise Test Report for the ARE 442 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Huskey, A.; van Dam, J.

2010-11-01

This test was conducted on the ARE 442 as part of the U.S. Department of Energy's (DOE's) Independent Testing project. This project was established to help reduce the barriers of wind energy expansion by providing independent testing results for small turbines. In total, five turbines are being tested at the National Wind Technology Center (NWTC) as a part of this project. Acoustic noise testing is one of up to five tests that may be performed on the turbines, including duration, safety and function, power performance, and power quality tests. The acoustic noise test was conducted to the IEC 61400-11 Edition 2.1.

Toward an Integrated Optical Data System for Wind Tunnel Testing

National Research Council Canada - National Science Library

Ruyten, Wim

1999-01-01

...) of the test article in a wind tunnel test. The theory for such P&A determinations is developed and applied to data from a recent pressure sensitive paint test in AEDC's 16 ft transonic wind tunnel...

Duration Test Report for the Entegrity EW50 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

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

2012-12-01

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

Nano-ADEPT Aeroloads Wind Tunnel Test

Science.gov (United States)

Smith, Brandon; Yount, Bryan; Kruger, Carl; Brivkalns, Chad; Makino, Alberto; Cassell, Alan; Zarchi, Kerry; McDaniel, Ryan; Ross, James; Wercinski, Paul;

SMART wind turbine rotor. Design and field test

Energy Technology Data Exchange (ETDEWEB)

Berg, Jonathan Charles; Resor, Brian Ray; Paquette, Joshua A.; White, Jonathan Randall

2014-01-01

The Wind Energy Technologies department at Sandia National Laboratories has developed and field tested a wind turbine rotor with integrated trailing-edge flaps designed for active control of rotor aerodynamics. The SMART Rotor project was funded by the Wind and Water Power Technologies Office of the U.S. Department of Energy (DOE) and was conducted to demonstrate active rotor control and evaluate simulation tools available for active control research. This report documents the design, fabrication, and testing of the SMART Rotor. This report begins with an overview of active control research at Sandia and the objectives of this project. The SMART blade, based on the DOE / SNL 9-meter CX-100 blade design, is then documented including all modifications necessary to integrate the trailing edge flaps, sensors incorporated into the system, and the fabrication processes that were utilized. Finally the test site and test campaign are described.

European wind turbine testing procedure developments. Task 1: Measurement method to verify wind turbine performance characteristics

Energy Technology Data Exchange (ETDEWEB)

Hunter, R.; Friis Pedersen, T.; Dunbabin, P.; Antoniou, I.; Frandsen, S.; Klug, H.; Albers, A.; Lee, W.K.

2001-01-01

There is currently significant standardisation work ongoing in the context of wind farm energy yield warranty assessment and wind turbine power performance testing. A standards maintenance team is revising the current IEC (EN) 61400-12 Ed 1 standard for wind turbine power performance testing. The standard is being divided into four documents. Two of them are drafted for evaluation and verification of complete wind farms and of individual wind turbines within wind farms. This document, and the project it describes, has been designed to help provide a solid technical foundation for this revised standard. The work was wide ranging and addressed 'grey' areas of knowledge, regarding existing methodologies or to carry out basic research in support of fundamentally new procedures. The work has given rise to recommendations in all areas of the work, including site calibration procedures, nacelle anemometry, multi-variate regression analysis and density normalisation. (au)

Cooperative field test program for wind systems. Final report

Energy Technology Data Exchange (ETDEWEB)

Bollmeier, W.S. II; Dodge, D.M.

1992-03-01

The objectives of the Federal Wind Energy Program, managed by the US Department of Energy (DOE), are (1) to assist industry and utilities in achieving a multi-regional US market penetration of wind systems, and (2) to establish the United States as the world leader in the development of advanced wind turbine technology. In 1984, the program conducted a series of planning workshops with representatives from the wind energy industry to obtain input on the Five-Year Research Plan then being prepared by DOE. One specific suggestion that came out of these meetings was that the federal program should conduct cooperative research tests with industry to enhance the technology transfer process. It was also felt that the active involvement of industry in DOE-funded research would improve the state of the art of wind turbine technology. DOE established the Cooperative Field Test Program (CFTP) in response to that suggestion. This program was one of the first in DOE to feature joint industry-government research test teams working toward common objectives.

European wind turbine testing procedure developments. Task 1: Measurement method to verify wind turbine performance characteristics

DEFF Research Database (Denmark)

Hunter, R.; Friis Pedersen, Troels; Dunbabin, P.

2001-01-01

There is currently significant standardisation work ongoing in the context of wind farm energy yield warranty assessment and wind turbine power performance testing. A standards maintenance team is revising the current IEC (EN) 61400-12 Ed 1 standard forwind turbine power performance testing....... The standard is being divided into four documents. Two of them are drafted for evaluation and verification of complete wind farms and of individual wind turbines within wind farms. This document, and the project itdescribes, has been designed to help provide a solid technical foundation for this revised...... standard. The work was wide ranging and addressed 'grey' areas of knowledge, regarding existing methodologies or to carry out basic research in support offundamentally new procedures. The work has given rise to recommendations in all areas of the work, including site calibration procedures, nacelle...

EVALUATION OF DNA INTEGRITY USING TUNEL AND COMET ASSAY IN HUMAN SEMEN: IMMEDIATE- VERSUS DELAYED-FREEZING

Science.gov (United States)

EVALUATION OF DNA INTEGRITY USING TUNEL AND COMET ASSAY IN HUMAN SEMEN: IMMEDIATE- VERSUS DELAYED-FREEZING K. Young,* L. Xun,* S. Rothmann,? S. Perreault, ? W. Robbins**University of California, Los Angeles, Los Angeles, California; ?Fertility Solutions Inc., Cleveland, ...

Performance testing of a small vertical-axis wind turbine

Energy Technology Data Exchange (ETDEWEB)

Bravo, R.; Tullis, S.; Ziada, S. [McMaster Univ., Hamilton, ON (Canada). Dept. of Mechanical Engineering

2007-07-01

Full-scale wind tunnel testing of a prototype 3.5 kW vertical-axis wind turbine (VAWT) was conducted in a low speed wind tunnel in Ottawa. The tests were conducted to determine nominal power curves as well as the system's structural integrity, safety and operational characteristics. Dimensionless power curves were used to assess the relation between the wind turbine's rotary speed and the produced power for various wind speeds. Tests began at the lowest wind speed and revolutions per minute (RPM) and were gradually increased. A proximity sensor was used to determine the passing frequency of spaced bolts. The aerodynamic performance of the turbine was evaluated using a servo-controlled mechanical variable load with a disc brake calliper and electro-hydraulic servo-actuator. A load cell was used to measure torque produced by the turbine. An active closed loop speed control system was used to regulate the rotary speed of the turbine. The system used a high gain proportional control law to guarantee stability. Calculated power was based on the average rotary speed measurement. Results of the study suggested that the dimensional power performance of the turbine could be predicted from the curve for all rotary speeds and for wind speeds between 8 and 16 m/s. The maximum power coefficient of 0.3 occurred at a tip speed ratio of 1.6. Test results demonstrated that the turbine reached its rated power at 14 m/s. However, the range of tip speed ratios for power production were lower than the range for most other small VAWT. 2 refs., 3 figs.

Wind tunnel testing of the DeepWind demonstrator in design and tilted operating conditions

DEFF Research Database (Denmark)

Battistia, L.; Benini, E.; Brighenti, A.

2016-01-01

The DeepWind Project aims at investigating the feasibility of a new floating vertical-axis wind turbine (VAWT) concept, whose purpose is to exploit wind resources at deep-water offshore sites. The results of an extensive experimental campaign on the DeepWind reduced scale demonstrator are here...... was installed on a high precision test bench, whose axis was suitable to be inclined up to 15° with respect to the design (i.e. upright) operating condition. The experiments were performed at the large scale, high speed wind tunnel of the Politecnico di Milano (Italy), using a “free jet” (open channel...... presented for different wind speeds and rotor angular velocities, including also skewed flow operation due to a tilted rotor arrangement. To accomplish this, after being instrumented to measure aerodynamic power and thrust (both in streamwise and transversal directions), a troposkien three-bladed rotor...

Characterization of a new open jet wind tunnel to optimize and test vertical axis wind turbines

DEFF Research Database (Denmark)

Tourn, Silvana; Pallarès, Jordi; Cuesta, Ildefonso

2017-01-01

Based on the increasing interest in urban environmental technologies, the study of small scale vertical axis wind turbines shows motivating challenges. In this paper, we present the characteristics and potentials of a new open jet wind tunnel. It has a nozzle exit area of 1.5 × 1.5 m2, and it can......%. The detailed characterization of the flow carried out indicates that the wind tunnel can be used to test small scale models of wind turbines....

Enertech 2-kW high-reliability wind system. Phase II. Fabrication and testing

Energy Technology Data Exchange (ETDEWEB)

Cordes, J A; Johnson, B A

1981-06-01

A high-reliability wind machine rated for 2 kW in a 9 m/s wind has been developed. Activities are summarized that are centered on the fabrication and testing of prototypes of the wind machine. The test results verified that the wind machine met the power output specification and that the variable-pitch rotor effectively controlled the rotor speed for wind speeds up to 50 mph. Three prototypes of the wind machine were shipped to the Rocky Flats test center in September through November of 1979. Work was also performed to reduce the start-up wind speed. The start-up wind speed to the Enertech facility has been reduced to 4.5 m/s.

Wind Tunnel Aeroacoustic Tests of Six Airfoils for Use on Small Wind Turbines; Period of Performance: August 23, 2002 through March 31, 2004

Energy Technology Data Exchange (ETDEWEB)

Oerlemans, S.

2004-08-01

The U.S. Department of Energy, working through the National Renewable Energy Laboratory, is engaged in a comprehensive research effort to improve our understanding of wind turbine aeroacoustics. Quiet wind turbines are an inducement to widespread deployment, so the goal of NREL's aeroacoustic research is to develop tools that the U.S. wind industry can use in developing and deploying highly efficient, quiet wind turbines at low wind speed sites. NREL's National Wind Technology Center is implementing a multifaceted approach that includes wind tunnel tests, field tests, and theoretical analyses in direct support of low wind speed turbine development by its industry partners. To that end, wind tunnel aerodynamic tests and aeroacoustic tests have been performed on six airfoils that are candidates for use on small wind turbines. Results are documented in this report.

Grid Simulator for Testing a Wind Turbine on Offshore Floating Platform

Energy Technology Data Exchange (ETDEWEB)

Gevorgian, V.

2012-02-01

An important aspect of such offshore testing of a wind turbine floating platform is electrical loading of the wind turbine generator. An option of interconnecting the floating wind turbine with the onshore grid via submarine power cable is limited by many factors such as costs and associated environmental aspects (i.e., an expensive and lengthy sea floor study is needed for cable routing, burial, etc). It appears to be a more cost effective solution to implement a standalone grid simulator on a floating platform itself for electrical loading of the test wind turbine. Such a grid simulator must create a stable fault-resilient voltage and frequency bus (a micro grid) for continuous operation of the test wind turbine. In this report, several electrical topologies for an offshore grid simulator were analyzed and modeled.

Verification test for three WindCube WLS7 LiDARs at the Høvsøre test site

DEFF Research Database (Denmark)

Gottschall, Julia; Courtney, Michael

The report describes the procedure of testing ground-based WindCube lidars (manufactured by the French company Leosphere) at the Høvsøre test site in comparison to reference sensors mounted at a meteorological mast. Results are presented for three tested units – in detail for unit WLS7-0062, and ......-0062, and in a summary for units WLS7-0064 and WLS7-0066. The verification test covers the evaluation of measured mean wind speeds, wind directions and wind speed standard deviations. The data analysis is basically performed in terms of different kinds of regression analyses.......The report describes the procedure of testing ground-based WindCube lidars (manufactured by the French company Leosphere) at the Høvsøre test site in comparison to reference sensors mounted at a meteorological mast. Results are presented for three tested units – in detail for unit WLS7...

The system design and performance test of hybrid vertical axis wind turbine

Science.gov (United States)

Dwiyantoro, Bambang Arip; Suphandani, Vivien

2017-04-01

Vertical axis wind turbine is a tool that is being developed to generate energy from wind. One cause is still little use of wind energy is the design of wind turbines that are less precise. Therefore in this study will be developed the system design of hybrid vertical axis wind turbine and tested performance with experimental methods. The design of hybrid turbine based on a straight bladed Darrieus turbine along with a double step Savonius turbine. The method used to design wind turbines is by studying literature, analyzing the critical parts of a wind turbine and the structure of the optimal design. Wind turbine prototype of the optimal design characteristic tests in the wind tunnel experimentally by varying the speed of the wind. From the experimental results show that the greater the wind speed, the greater the wind turbine rotation and torque is raised. The hybrid vertical axis wind turbine has much better self-starting and better conversion efficiency.

The Triple Spar campaign: Model tests of a 10MW floating wind turbine with waves, wind and pitch control

DEFF Research Database (Denmark)

Bredmose, Henrik; Lemmer, F.; Borg, Michael Borg

2017-01-01

Results of a test campaign for a floating wind turbine in simultaneous wind and wave forcing at scale 1:60 are presented. The floater is the Triple Spar floater, a hybrid between a spar buoy and a semi submersible tri-floater, tested here for the first time. The turbine is a model scale version...... of the DTU 10 MW reference wind turbine, which, also for the first time, is tested with active blade pitch control. The tests focus on the effects of aerodynamic damping and interaction effects between the wind forcing, wave forcing and the blade pitch control algorithm. Special focus is devoted...... to the instability of the platform pitch natural mode, that can occur if a standard land-based controller is applied....

European wind turbine testing procedure developments. Task 2: Power quality

DEFF Research Database (Denmark)

Sørensen, Poul Ejnar; Friis Pedersen, Troels; Gerdes, G.

2001-01-01

The present report describes the work done in the power quality subtask of the European Wind Turbine Testing Procedure Developments project funded by the EU SMT program. The objective of the power quality subtask has been to make recommendations andprovide background for new standards...... for measurement and testing of wind turbine power quality. The focus in the work has been to support the ongoing standardisation work in IEC with a new standard IEC61400-21 for measurement and assessment of powerquality characteristics of grid connected wind turbines. The work has also been based on the power...... quality measuremnet procedure in the Measnet cooperation of European test stations for wind turbines. The first working item of the project has been toverify the state of the art of the measurement procedures by analyses and comparisons of the measurements and data processing software of the participating...

Controlled Velocity Testing of an 8-kW Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Larwood, S.; Sencenbaugh, J.; Acker, B.

2001-07-31

This paper describes a case study of the controlled-velocity test of an 8-kW wind turbine. The turbine was developed in response to the U.S. Department of Energy's small wind turbine program. As background, the prototype development is discussed. The turbine mechanical and electrical components are described. The turbine was tested on a flatbed truck and driven down an airfield runway at constant relative wind speed. Horizontal furling was used to control over-speed. Various parameters were changed to determine their effects on furling. The testing showed that the machine had insufficient rotor offset for adequate furling. Also, a rotor resonance problem was discovered and remedied. Problems associated with taking the measurements made it difficult to determine if the truck test was a suitable method for code validation. However, qualitative observations gleaned from the testing justified the effort.

1:50 Scale Testing of Three Floating Wind Turbines at MARIN and Numerical Model Validation Against Test Data

Energy Technology Data Exchange (ETDEWEB)

Dagher, Habib [Univ. of Maine, Orno, ME (United States); Viselli, Anthony [Univ. of Maine, Orno, ME (United States); Goupee, Andrew [Univ. of Maine, Orno, ME (United States); Allen, Christopher [Univ. of Maine, Orno, ME (United States)

2017-08-15

The primary goal of the basin model test program discussed herein is to properly scale and accurately capture physical data of the rigid body motions, accelerations and loads for different floating wind turbine platform technologies. The intended use for this data is for performing comparisons with predictions from various aero-hydro-servo-elastic floating wind turbine simulators for calibration and validation. Of particular interest is validating the floating offshore wind turbine simulation capabilities of NREL’s FAST open-source simulation tool. Once the validation process is complete, coupled simulators such as FAST can be used with a much greater degree of confidence in design processes for commercial development of floating offshore wind turbines. The test program subsequently described in this report was performed at MARIN (Maritime Research Institute Netherlands) in Wageningen, the Netherlands. The models considered consisted of the horizontal axis, NREL 5 MW Reference Wind Turbine (Jonkman et al., 2009) with a flexible tower affixed atop three distinct platforms: a tension leg platform (TLP), a spar-buoy modeled after the OC3 Hywind (Jonkman, 2010) and a semi-submersible. The three generic platform designs were intended to cover the spectrum of currently investigated concepts, each based on proven floating offshore structure technology. The models were tested under Froude scale wind and wave loads. The high-quality wind environments, unique to these tests, were realized in the offshore basin via a novel wind machine which exhibits negligible swirl and low turbulence intensity in the flow field. Recorded data from the floating wind turbine models included rotor torque and position, tower top and base forces and moments, mooring line tensions, six-axis platform motions and accelerations at key locations on the nacelle, tower, and platform. A large number of tests were performed ranging from simple free-decay tests to complex operating conditions with

Build an Inexpensive Wind Tunnel to Test CO2 Cars

Science.gov (United States)

McCormick, Kevin

2012-01-01

As part of the technology education curriculum, the author's eighth-grade students design, build, test, and race CO2 vehicles. To help them in refining their designs, they use a wind tunnel to test for aerodynamic drag. In this article, the author describes how to build a wind tunnel using inexpensive, readily available materials. (Contains 1…

Safety and Function Test Report for the Viryd CS8 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Roadman, J.; Murphy, M.; van Dam, J.

2013-10-01

This test was conducted as part of the U.S. Department of Energy's (DOE) Independent Testing project. This project was established to help reduce the barriers of wind energy expansion by providing independent testing results for small turbines. Several turbines were selected for testing at the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL) as a part of the Small Wind Turbine Independent Testing project. Safety and function testing is one of up to five tests that may be performed on the turbines. Other tests include duration, power performance, acoustic noise, and power quality. Viryd Technologies, Inc. of Austin, Texas, was the recipient of the DOE grant and provided the turbine for testing.

Full scale testing for investigation of wind turbine seismic response

Energy Technology Data Exchange (ETDEWEB)

Prowell, I.; Veletzos, M.; Elgamal, A. [California Univ., San Diego, CA (United States). Dept. of Structural Engineering

2008-07-01

In 2007, much of the growth in wind energy development was concentrated in North America and Asia, two regions which periodically experience strong earthquakes that may impact the final turbine design. As such, rational prediction of seismic hazards must be considered in order to maintain and enhance the ability of wind power to compete economically with other energy sources. In response to this challenge, researchers at the University of California, San Diego (UCSD) have experimentally investigated wind turbines to gain an understanding of expected earthquake forces. This paper described the experimental setup for a full scale shake table test of a 65 kW wind turbine. The turbine was excited perpendicular to the axis of the rotor with a seismic base shaking record scaled to various levels. The data was analyzed using simple but effective procedures to provide insight into the observed structural damping of the wind turbine. The experimental investigation showed that full scale seismic testing of wind turbines is possible and can provide valuable insight into dynamic behaviour of wind turbines. The results can be used to develop a more accurate picture of how wind turbines are impacted by earthquakes. The data regarding the low observed super-structure damping provides a basis for calibration and further development of verified design procedures. 20 refs., 3 tabs.

SMART Rotor Development and Wind Tunnel Test

Science.gov (United States)

2009-09-01

amplifier and control system , and data acquisition, processing, and display systems . Boeing�s LRTS (Fig. 2), consists of a sled structure that...Support Test Stand Sled Tail Sting Outrigger Arm Figure 2: System integration test at whirl tower Port Rotor Balance Main Strut Flap Tail...demonstrated. Finally, the reliability of the flap actuation system was successfully proven in more than 60 hours of wind tunnel testing

Climate-conscious architecture. Design and wind testing method for climates in change

Energy Technology Data Exchange (ETDEWEB)

Kuismanen, K.

2008-07-01

The main objective of this research was to develop practical tools with which it is possible to improve the environment, micro-climate and energy economy of buildings and plans in different climate zones, and take the climate change into account. The parts of the study are: State of art study into existing know-how about climate and planning. Study of the effects of climate change on the built environment. Development of simple micro-climate, nature and built environment analysis methods. Defining the criteria of an acceptable micro-climatic environment. Development of the wind test blower. Presenting ways to interpret test results and draw conclusions. Development of planning and design guidelines for different climate zones. An important part of the research is the development of the CASE wind test instrument, different wind simulation techniques, and the methods of observing the results. Bioclimatic planning and architectural design guidelines for different climate zones are produced. The analyse tools developed give a qualitative overall view, which can be deepened towards a quantitative analyse with wind testing measurements and roughness calculations. No mechanical rules are suggested, but complementary viewpoints and practices introduced to a normal planning process as well as improvement of consultative knowledge. The 'method' is that there is no strict mechanical method, but a deeper understanding of bioclimatic matters. Climate-conscious planning with the developed CASE method, make it possible to design a better micro-climate for new or old built-up areas. Winds can be used in to ventilate exhaust fumes and other pollutants, which improves the quality of air and the healthiness of the urban environment. The analyses and scale-model tests make it possible to shield cold windy areas and to diminish the cooling effect of wind on facades. According to studies in Scandinavian countries this will bring energy savings of 5-15 per cent. The method can

Reliability of wind turbine blades: An overview of materials testing

DEFF Research Database (Denmark)

Holmes, John W.; Sørensen, Bent F.; Brøndsted, Povl

2007-01-01

an understanding of how damage develops in composite structures, composite materials and adhesives. Designing reliable wind turbine blades also requires the further development of laboratory scale and full scale test methods to evaluate the structural response and durability of new materials under various loading......The structural reliability of wind turbine components can have a profound impact on both the profitability and reputation of a wind turbine manufacturer or supplier of wind turbine components. The issue of reliability is of critical concern when large wind farm co-operatives are considered......, and when wind turbines are located in remote regions where the cost of inspections and repairs can be very high. From a structural viewpoint, wind turbine blades are subjected to very complex loading histories with coupled deformation modes. The long-term reliability of wind turbine blades requires...

First International Workshop on Grid Simulator Testing of Wind Turbine Drivetrains: Workshop Proceedings

Energy Technology Data Exchange (ETDEWEB)

Gevorgian, V.; Link, H.; McDade, M.; Mander, A.; Fox, J. C.; Rigas, N.

2013-11-01

This report summarizes the proceedings of the First International Workshop on Grid Simulator Testing of Wind Turbine Drivetrains, held from June 13 to 14, 2013, at the National Renewable Energy Laboratory's National Wind Technology Center, located south of Boulder, Colorado. The workshop was sponsored by the U.S. Department of Energy and cohosted by the National Renewable Energy Laboratory and Clemson University under ongoing collaboration via a cooperative research and development agreement. The purpose of the workshop was to provide a forum to discuss the research, testing needs, and state-of-the-art apparatuses involved in grid compliance testing of utility-scale wind turbine generators. This includes both dynamometer testing of wind turbine drivetrains ('ground testing') and field testing grid-connected wind turbines. Four sessions followed by discussions in which all attendees of the workshop were encouraged to participate comprised the workshop.

Correlations of Platooning Track Test and Wind Tunnel Data

Energy Technology Data Exchange (ETDEWEB)

Lammert, Michael P. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kelly, Kenneth J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yanowitz, Janet [Ecoengineering, Sharonville, OH (United States)

2018-02-02

In this report, the National Renewable Energy Laboratory analyzed results from multiple, independent truck platooning projects to compare and contrast track test results with wind tunnel test results conducted by Lawrence Livermore National Laboratory (LLNL). Some highlights from the report include compiled data, and results from four independent SAE J1321 full-size track test campaigns that were compared to LLNL wind tunnel testing results. All platooning scenarios tested demonstrated significant fuel savings with good correlation relative to following distances, but there are still unanswered questions and clear opportunities for system optimization. NOx emissions showed improvements from NREL tests in 2014 to Auburn tests in 2015 with respect to J1321 platooning track testing of Peloton system. NREL evaluated data from Volpe's Naturalistic Study of Truck Following Behavior, which showed minimal impact of naturalistic background platooning. We found significant correlation between multiple track studies, wind tunnel tests, and computational fluid dynamics, but also showed that there is more to learn regarding close formation and longer-distance effects. We also identified potential areas for further research and development, including development of advanced aerodynamic designs optimized for platooning, measurement of platoon system performance in traffic conditions, impact of vehicle lateral offsets on platooning performance, and characterization of the national potential for platooning based on fleet operational characteristics.

Rotary Balance Wind Tunnel Testing for the FASER Flight Research Aircraft

Science.gov (United States)

Denham, Casey; Owens, D. Bruce

2016-01-01

Flight dynamics research was conducted to collect and analyze rotary balance wind tunnel test data in order to improve the aerodynamic simulation and modeling of a low-cost small unmanned aircraft called FASER (Free-flying Aircraft for Sub-scale Experimental Research). The impetus for using FASER was to provide risk and cost reduction for flight testing of more expensive aircraft and assist in the improvement of wind tunnel and flight test techniques, and control laws. The FASER research aircraft has the benefit of allowing wind tunnel and flight tests to be conducted on the same model, improving correlation between wind tunnel, flight, and simulation data. Prior wind tunnel tests include a static force and moment test, including power effects, and a roll and yaw damping forced oscillation test. Rotary balance testing allows for the calculation of aircraft rotary derivatives and the prediction of steady-state spins. The rotary balance wind tunnel test was conducted in the NASA Langley Research Center (LaRC) 20-Foot Vertical Spin Tunnel (VST). Rotary balance testing includes runs for a set of given angular rotation rates at a range of angles of attack and sideslip angles in order to fully characterize the aircraft rotary dynamics. Tests were performed at angles of attack from 0 to 50 degrees, sideslip angles of -5 to 10 degrees, and non-dimensional spin rates from -0.5 to 0.5. The effects of pro-spin elevator and rudder deflection and pro- and anti-spin elevator, rudder, and aileron deflection were examined. The data are presented to illustrate the functional dependence of the forces and moments on angle of attack, sideslip angle, and angular rate for the rotary contributions to the forces and moments. Further investigation is necessary to fully characterize the control effectors. The data were also used with a steady state spin prediction tool that did not predict an equilibrium spin mode.

Wind Tunnel and Hover Performance Test Results for Multicopter UAS Vehicles

Science.gov (United States)

Russell, Carl R.; Jung, Jaewoo; Willink, Gina; Glasner, Brett

2016-01-01

There is currently a lack of published data for the performance of multicopter unmanned aircraft system (UAS) vehicles, such as quadcopters and octocopters, often referred to collectively as drones. With the rapidly increasing popularity of multicopter UAS, there is interest in better characterizing the performance of this type of aircraft. By studying the performance of currently available vehicles, it will be possible to develop models for vehicles at this scale that can accurately predict performance and model trajectories. This paper describes a wind tunnel test that was recently performed in the U.S. Army's 7- by 10-ft Wind Tunnel at NASA Ames Research Center. During this wind tunnel entry, five multicopter UAS vehicles were tested to determine forces and moments as well as electrical power as a function of wind speed, rotor speed, and vehicle attitude. The test is described here in detail, and a selection of the key results from the test is presented.

Concept Testing of a Simple Floating Offshore Vertical Axis Wind Turbine

DEFF Research Database (Denmark)

Friis Pedersen, Troels; Schmidt Paulsen, Uwe; Aagaard Madsen, Helge

2013-01-01

The wind energy community is researching new concepts for deeper sea offshore wind turbines. One such concept is the DeepWind concept. The concept is being assessed in a EU-FP7 project, called DeepWind. Objectives of this project are to assess large size wind turbines (5-20MW) based on the concept...... varying wind and wave conditions, and to compare such behaviour with computer code calculations. The concept turbine was designed and constructed by the project task partners, and all parts were assembled and installed at sea in the Roskilde fjord right next to DTU Risø campus. The turbine is under....... One task in the project is to test a 1kW concept rotor (not a scaled down MW size rotor) partly under field conditions in a fjord in Denmark, partly in a water tank under controlled conditions in Netherlands. The objective of testing the 1kW concept turbine is to verify the dynamical behaviour under...

Wind pressure testing of tornado safe room components made from wood

Science.gov (United States)

Robert Falk; Deepak Shrestha

2016-01-01

To evaluate the ability of a wood tornado safe room to resist wind pressures produced by a tornado, two safe room com-ponents were tested for wind pressure strength. A tornado safe room ceiling panel and door were static-pressure-tested according to ASTM E 330 using a vacuum test system. Re-sults indicate that the panels had load capacities from 2.4 to 3.5 times that...

Stochastic models for strength of wind turbine blades using tests

DEFF Research Database (Denmark)

Toft, H.S.; Sørensen, John Dalsgaard

2008-01-01

The structural cost of wind turbine blades is dependent on the values of the partial safety factors which reflect the uncertainties in the design values, including statistical uncertainty from a limited number of tests. This paper presents a probabilistic model for ultimate and fatigue strength...... of wind turbine blades especially considering the influence of prior knowledge and test results and how partial safety factors can be updated when additional full-scale tests are performed. This updating is performed by adopting a probabilistic design basis based on Bayesian statistical methods....

Methodology for testing subcomponents; background and motivation for subcomponent testing of wind turbine rotor blades

DEFF Research Database (Denmark)

Antoniou, Alexandros; Branner, Kim; Lekou, D.J.

2016-01-01

This report aims to provide an overview of the design methodology followed by wind turbine blade structural designers, along with the testing procedure on full scale blades which are followed by testing laboratories for blade manufacturers as required by the relevant standards and certification...... bodies’ recommendations for design and manufacturing verification. The objective of the report is not to criticize the design methodology or testing procedure and the standards thereof followed in the wind energy community, but to identify those items offered by state of the art structural design tools...... investigations performed are based on the INNWIND.EU reference 10MW horizontal axis wind turbine [1]. The structural properties and material and layout definition used within IRPWIND are defined in the INNWIND.EU report [2]. The layout of the report includes a review of the structural analysis models used...

Optimal sensor placement for modal testing on wind turbines

Science.gov (United States)

Schulze, Andreas; Zierath, János; Rosenow, Sven-Erik; Bockhahn, Reik; Rachholz, Roman; Woernle, Christoph

2016-09-01

The mechanical design of wind turbines requires a profound understanding of the dynamic behaviour. Even though highly detailed simulation models are already in use to support wind turbine design, modal testing on a real prototype is irreplaceable to identify site-specific conditions such as the stiffness of the tower foundation. Correct identification of the mode shapes of a complex mechanical structure much depends on the placement of the sensors. For operational modal analysis of a 3 MW wind turbine with a 120 m rotor on a 100 m tower developed by W2E Wind to Energy, algorithms for optimal placement of acceleration sensors are applied. The mode shapes used for the optimisation are calculated by means of a detailed flexible multibody model of the wind turbine. Among the three algorithms in this study, the genetic algorithm with weighted off-diagonal criterion yields the sensor configuration with the highest quality. The ongoing measurements on the prototype will be the basis for the development of optimised wind turbine designs.

Testing of a direct drive generator for wind turbines

Energy Technology Data Exchange (ETDEWEB)

Sondergaard, L.M. [Riso National Laboratory, Roskilde (Denmark)

1996-12-31

The normal drive train of a wind turbine consists a gearbox and a 4 to 8 poles asynchronous generator. The gearbox is an expensive and unreliable components and this paper deals with testing of a direct drive synchronous generator for a gearless wind turbine. The Danish company Belt Electric has constructed and manufactured a 27 kW prototype radial flux PM-generator (DD600). They have used cheap hard ferrite magnets in the rotor of this PM-generator. This generator has been tested at Riso and the test results are investigated and analyzed in this paper. The tests have been done with three different load types (1: resistance; 2: diode rectifier, DC-capacitor, resistance; 3: AC-capacitor, diode rectifier, DC-capacitor, resistance). 1 ref., 9 figs., 5 tabs.

The DFVLR wind-energy test facility 'Ulrich Huetter' on Schnittlinger Berg

Science.gov (United States)

Kussmann, Alfred

1986-11-01

The DFVLR test facility for wind-energy systems (named after Ulrich Huetter, the designer of the 100-kW GFRP-rotor W 34 wind turbine first manufactured and tested in the 1950s) is described and illustrated with photographs. The history of the facility is traced, and current operations in gathering, archiving, processing, interpreting, and documenting performance-test data are outlined. The facility includes instrumentation for rotor telemetry, gondola motion measurements, and ground measurements and provides testing services to private users on both contract and leasing bases.

SMART Wind Turbine Rotor: Design and Field Test

Energy Technology Data Exchange (ETDEWEB)

Berg, Jonathan C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Resor, Brian R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Paquette, Joshua A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); White, Jonathan R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-01-29

This report documents the design, fabrication, and testing of the SMART Rotor. This work established hypothetical approaches for integrating active aerodynamic devices (AADs) into the wind turbine structure and controllers.

Structural Testing of the Blade Reliability Collaborative Effect of Defect Wind Turbine Blades

Energy Technology Data Exchange (ETDEWEB)

Desmond, M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hughes, S. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paquette, J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-06-08

Two 8.3-meter (m) wind turbine blades intentionally constructed with manufacturing flaws were tested to failure at the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL) south of Boulder, Colorado. Two blades were tested; one blade was manufactured with a fiberglass spar cap and the second blade was manufactured with a carbon fiber spar cap. Test loading primarily consisted of flap fatigue loading of the blades, with one quasi-static ultimate load case applied to the carbon fiber spar cap blade. Results of the test program were intended to provide the full-scale test data needed for validation of model and coupon test results of the effect of defects in wind turbine blade composite materials. Testing was part of the Blade Reliability Collaborative (BRC) led by Sandia National Laboratories (SNL). The BRC seeks to develop a deeper understanding of the causes of unexpected blade failures (Paquette 2012), and to develop methods to enable blades to survive to their expected operational lifetime. Recent work in the BRC includes examining and characterizing flaws and defects known to exist in wind turbine blades from manufacturing processes (Riddle et al. 2011). Recent results from reliability databases show that wind turbine rotor blades continue to be a leading contributor to turbine downtime (Paquette 2012).

Wind Turbine Test. Wind Matic WM 17S

DEFF Research Database (Denmark)

Friis Pedersen, Troels

The report describes standard measurements performed on a Wind-Matic WM 17S, 75 kW wind turbine. The measurements carried out and reported here comprises the power output, system efficiency, energy production, transmission efficiency, rotor power, rotor efficiency, air-brakes efficiency, structural...

Wind Turbine Test Wind Matic WM 15S

DEFF Research Database (Denmark)

Friis Pedersen, Troels

The report describes standard measurements performed on a Wind-Matic WM 15S, 55 kW wind turbine. The measurements carried out and reported here comprises the power output, system efficiency, energy production, transmission efficiency, rotor power, rotor efficiency, air-brakes efficiency, dynamical...

Power Performance Verification of a Wind Farm Using the Friedman's Test.

Science.gov (United States)

Hernandez, Wilmar; López-Presa, José Luis; Maldonado-Correa, Jorge L

2016-06-03

In this paper, a method of verification of the power performance of a wind farm is presented. This method is based on the Friedman's test, which is a nonparametric statistical inference technique, and it uses the information that is collected by the SCADA system from the sensors embedded in the wind turbines in order to carry out the power performance verification of a wind farm. Here, the guaranteed power curve of the wind turbines is used as one more wind turbine of the wind farm under assessment, and a multiple comparison method is used to investigate differences between pairs of wind turbines with respect to their power performance. The proposed method says whether the power performance of the specific wind farm under assessment differs significantly from what would be expected, and it also allows wind farm owners to know whether their wind farm has either a perfect power performance or an acceptable power performance. Finally, the power performance verification of an actual wind farm is carried out. The results of the application of the proposed method showed that the power performance of the specific wind farm under assessment was acceptable.

Numerical forecast test on local wind fields at Qinshan Nuclear Power Plant

International Nuclear Information System (INIS)

Chen Xiaoqiu

2005-01-01

Non-hydrostatic, full compressible atmospheric dynamics model is applied to perform numerical forecast test on local wind fields at Qinshan nuclear power plant, and prognostic data are compared with observed data for wind fields. The results show that the prognostic of wind speeds is better than that of wind directions as compared with observed results. As the whole, the results of prognostic wind field are consistent with meteorological observation data, 54% of wind speeds are within a factor of 1.5, about 61% of the deviation of wind direction within the 1.5 azimuth (≤33.75 degrees) in the first six hours. (authors)

Wind Generators Test Bench. Optimal Design of PI Controller

Directory of Open Access Journals (Sweden)

TUDORACHE, T.

2011-08-01

Full Text Available This paper proposes a novel and robust strategy for the optimal design of the drive system integrated in a wind generators test bench. The PI regulator coefficients used in control systems are usually computed based on simplified hypotheses and then tuned manually so as the system response meet certain specifications in terms of stability, accuracy and speed. The proposed methodology permits the automatic identification of PI regulator coefficients using intelligent optimization algorithms, the initial guess for the search procedure being determined based on particular simplified hypotheses. The proposed procedure can help the design engineers to drastically reduce the effort for finding the best PI regulator coefficients offering a range of feasible solutions depending on the imposed optimum criteria. The characteristics and performances of the optimization strategy are highlighted by using it for the design of a DC motor drive system used to simulate the wind prime mover integrated in a wind generators test bench.

IFT&E Industry Report Wind Turbine-Radar Interference Test Summary.

Energy Technology Data Exchange (ETDEWEB)

Karlson, Benjamin; LeBlanc, Bruce Philip.; Minster, David G; Estill, Milford; Miller, Bryan Edward; Busse, Franz (MIT LL); Keck, Chris (MIT LL); Sullivan, Jonathan (MIT LL); Brigada, David (MIT LL); Parker, Lorri (MIT LL); Younger, Richard (MIT LL); Biddle, Jason (MIT LL)

2014-10-01

Wind turbines have grown in size and capacity with today's average turbine having a power capacity of around 1.9 MW, reaching to heights of over 495 feet from ground to blade tip, and operating with speeds at the tip of the blade up to 200 knots. When these machines are installed within the line-of-sight of a radar system, they can cause significant clutter and interference, detrimentally impacting the primary surveillance radar (PSR) performance. The Massachusetts Institute of Technology's Lincoln Laboratory (MIT LL) and Sandia National Laboratories (SNL) were co-funded to conduct field tests and evaluations over two years in order to: I. Characterize the impact of wind turbines on existing Program-of-Record (POR) air surveillance radars; II. Assess near-term technologies proposed by industry that have the potential to mitigate the interference from wind turbines on radar systems; and III. Collect data and increase technical understanding of interference issues to advance development of long-term mitigation strategies. MIT LL and SNL managed the tests and evaluated resulting data from three flight campaigns to test eight mitigation technologies on terminal (short) and long-range (60 nmi and 250 nmi) radar systems. Combined across the three flight campaigns, more than 460 of hours of flight time were logged. This paper summarizes the Interagency Field Test & Evaluation (IFT&E) program and publicly- available results from the tests. It will also discuss the current wind turbine-radar interference evaluation process within the government and a proposed process to deploy mitigation technologies.

Standards for measurements and testing of wind turbine power quality

Energy Technology Data Exchange (ETDEWEB)

Soerensen, P [Risoe National Lab., Roskilde (Denmark); Gerdes, G; Klosse, R; Santjer, F [DEWI, Wilhelmshaven (Germany); Robertson, N; Davy, W [NEL, Glasgow (United Kingdom); Koulouvari, M; Morfiadakis, E [CRES, Pikermi (Greece); Larsson, Aa [Chalmers Univ. of Technology, Goeteborg (Sweden)

1999-03-01

The present paper describes the work done in power quality sub-task of the project `European Wind Turbine Testing Procedure Developments` funded by the EU SMT program. The objective of the power quality sub-task has been to make analyses and new recommendation(s) for the standardisation of measurement and verification of wind turbine power quality. The work has been organised in three major activities. The first activity has been to propose measurement procedures and to verify existing and new measurement procedures. This activity has also involved a comparison of the measurements and data processing of the participating partners. The second activity has been to investigate the influence of terrain, grid properties and wind farm summation on the power quality of wind turbines with constant rotor speed. The third activity has been to investigate the influence of terrain, grid properties and wind farm summation on the power quality of wind turbines with variable rotor speed. (au)

Characterization of a New Open Jet Wind Tunnel to Optimize and Test Vertical Axis Wind Turbines Using Flow Visualization and Measurement

DEFF Research Database (Denmark)

Tourn, S.; Gilabert, R.; Sánchez, V.

Characterize a new open jet wind tunnel and define the uniform test section where performance studies of small VAWTs will be carried out.......Characterize a new open jet wind tunnel and define the uniform test section where performance studies of small VAWTs will be carried out....

Anechoic wind tunnel tests on high-speed train bogie aerodynamic noise

OpenAIRE

Latorre Iglesias, E.; Thompson, D.; Smith, M.; Kitagawa, T.; Yamazaki, N.

2016-01-01

Aerodynamic noise becomes a significant noise source at speeds normally reached by high-speed trains. The train bogies are identified as important sources of aerodynamic noise. Due to the difficulty to assess this noise source carrying out field tests, wind tunnel tests offer many advantages. Tests were performed in the large-scale low-noise anechoic wind tunnel at Maibara, Japan, using a 1/7 scale train car and bogie model for a range of flow speeds between 50, 76, 89 and 100 m/s. The depend...

Test location Guetsch, Switzerland for wind-power installations; Teststandort fuer Windkraftanlagen Guetsch. Vorstudie

Energy Technology Data Exchange (ETDEWEB)

Schaffner, B.; Cattin, R.; Schilter, Ch.

2007-07-15

This illustrated technical report for the Swiss Federal Office of Energy (SFOE) describes work done on the preliminary project for providing test facilities for wind-power installations on the 'Guetsch' location in the Swiss Alps. In the context of the Alpine Test Site Guetsch project, which involves meteorological measurements and wind turbine performance analysis research, a comprehensive infrastructure for the acquisition of climate data and the performance of wind turbines has been defined. This work is to be carried out by the Swiss Federal Office of Meteorology and Climatology MeteoSwiss and the company Meteotest within the framework of the COST Action 727 2005 - 2008 of the European Union. The aim of this preliminary study is to identify the possibilities for the realisation of an alpine test site for wind turbines based on the existing infrastructure. The economic and technical conditions for the testing of both large and small wind turbines are discussed. Topics examined include site ownership and access, infrastructure and measurement systems, financing possibilities and a timeline for implementation.

Documentation and archiving of the Space Shuttle wind tunnel test data base. Volume 1: Background and description

Science.gov (United States)

Romere, Paul O.; Brown, Steve Wesley

1995-01-01

Development of the space shuttle necessitated an extensive wind tunnel test program, with the cooperation of all the major wind tunnels in the United States. The result was approximately 100,000 hours of space shuttle wind tunnel testing conducted for aerodynamics, heat transfer, and structural dynamics. The test results were converted into Chrysler DATAMAN computer program format to facilitate use by analysts, a very cost effective method of collecting the wind tunnel test results from many test facilities into one centralized location. This report provides final documentation of the space shuttle wind tunnel program. The two-volume set covers evolution of space shuttle aerodynamic configurations and gives wind tunnel test data, titles of wind tunnel data reports, sample data sets, and instructions for accessing the digital data base.

Design of multi-energy Helds coupling testing system of vertical axis wind power system

Science.gov (United States)

Chen, Q.; Yang, Z. X.; Li, G. S.; Song, L.; Ma, C.

2016-08-01

The conversion efficiency of wind energy is the focus of researches and concerns as one of the renewable energy. The present methods of enhancing the conversion efficiency are mostly improving the wind rotor structure, optimizing the generator parameters and energy storage controller and so on. Because the conversion process involves in energy conversion of multi-energy fields such as wind energy, mechanical energy and electrical energy, the coupling effect between them will influence the overall conversion efficiency. In this paper, using system integration analysis technology, a testing system based on multi-energy field coupling (MEFC) of vertical axis wind power system is proposed. When the maximum efficiency of wind rotor is satisfied, it can match to the generator function parameters according to the output performance of wind rotor. The voltage controller can transform the unstable electric power to the battery on the basis of optimizing the parameters such as charging times, charging voltage. Through the communication connection and regulation of the upper computer system (UCS), it can make the coupling parameters configure to an optimal state, and it improves the overall conversion efficiency. This method can test the whole wind turbine (WT) performance systematically and evaluate the design parameters effectively. It not only provides a testing method for system structure design and parameter optimization of wind rotor, generator and voltage controller, but also provides a new testing method for the whole performance optimization of vertical axis wind energy conversion system (WECS).

Wind Tunnel Tests of Parabolic Trough Solar Collectors: March 2001--August 2003

Energy Technology Data Exchange (ETDEWEB)

Hosoya, N.; Peterka, J. A.; Gee, R. C.; Kearney, D.

2008-05-01

Conducted extensive wind-tunnel tests on parabolic trough solar collectors to determine practical wind loads applicable to structural design for stress and deformation, and local component design for concentrator reflectors.

Refined Diebold-Mariano Test Methods for the Evaluation of Wind Power Forecasting Models

Directory of Open Access Journals (Sweden)

Hao Chen

2014-07-01

Full Text Available The scientific evaluation methodology for the forecast accuracy of wind power forecasting models is an important issue in the domain of wind power forecasting. However, traditional forecast evaluation criteria, such as Mean Squared Error (MSE and Mean Absolute Error (MAE, have limitations in application to some degree. In this paper, a modern evaluation criterion, the Diebold-Mariano (DM test, is introduced. The DM test can discriminate the significant differences of forecasting accuracy between different models based on the scheme of quantitative analysis. Furthermore, the augmented DM test with rolling windows approach is proposed to give a more strict forecasting evaluation. By extending the loss function to an asymmetric structure, the asymmetric DM test is proposed. Case study indicates that the evaluation criteria based on DM test can relieve the influence of random sample disturbance. Moreover, the proposed augmented DM test can provide more evidence when the cost of changing models is expensive, and the proposed asymmetric DM test can add in the asymmetric factor, and provide practical evaluation of wind power forecasting models. It is concluded that the two refined DM tests can provide reference to the comprehensive evaluation for wind power forecasting models.

Testing the effectiveness of monolayers under wind and wave conditions.

Science.gov (United States)

Palada, C; Schouten, P; Lemckert, C

2012-01-01

Monolayers are highly desirable for their evaporation reducing capabilities due to their relatively minimal cost and ease of application. Despite these positive attributes, monolayers have consistently failed to perform effectively due to the harsh wind and wave conditions prevalent across real-world water reserves. An exhaustive and consistent study testing the influence of wind and wave combinations on monolayer performance has yet to be presented in the literature. To remedy this, the effect of simultaneous wind and wave conditions on a benchmark high-performance monolayer (octadecanol suspension, CH(3)(CH(2))(16)CH(2)OH) has been analysed. Subjected only to waves, the monolayer remained intact due to its innate ability to compress and expand. However, the constant simultaneous application of wind and waves caused the monolayer to break up and gather down-wind where it volatilised over time. At wind speeds above 1.3 m s(-1) the monolayer was completely ineffective. For wind speeds below this threshold, the monolayer had an influence on the evaporation rate dependent on wind speed. From these results a series of application protocols can now be developed for the optimised deployment of monolayers in real-world water reserves. This will be of interest to private, commercial and government organisations involved in the storage and management of water resources.

Test Results of a Nb3Sn Wind/React ''Stress-Managed'' Block Dipole

International Nuclear Information System (INIS)

McInturff, A.; Bish, P.; Blackburn, R.; Diaczenko, N.; Elliott, T.; Hafalia Jr., R.; Henchel, W.; Jaisle, A.; Lau, W.; Lietzke, A.; McIntyre, P.; Noyes, P.; Nyman, M.; Sattarov, A.; Sattarov, A.

2006-01-01

A second phase of a highfield dipole technology development has been tested. A Nb3Sn block-coil model dipole was fabricated, using magnetic mirror geometry and wind/react coil technology. The primary objective of this phase was to make a first experimental test of the stress-management strategy pioneered at Texas A and M. In this strategy a high-strength support matrix is integrated with the windings to intercept Lorentz stress from the inner winding so that it does not accumulate in the outer winding. The magnet attained a field that was consistent with short sample limit on the first quench; there was no training. The decoupling of Lorentz stress between inner and outer windings was validated. In ramp rate studies the magnet exhibited a remarkable robustness in rapid ramping operation. It reached 85 percent of short sample(ss) current even while ramping 2-3 T/s. This robustness is attributed to the orientation of the Rutherford cables parallel to the field in the windings, instead of the transverse orientation that characterizes common dipole designs. Test results are presented and the next development phase plans are discussed

40 CFR 53.63 - Test procedure: Wind tunnel inlet aspiration test.

Science.gov (United States)

2010-07-01

... the sampler inlet opening centered in the sampling zone. To meet the maximum blockage limit of § 53.62(c)(1) or for convenience, part of the test sampler may be positioned external to the wind tunnel... = reference method sampler volumetric flow rate; and t = sampling time. (iii) Remove the reference method...

Static Aeroelastic Deformation Effects in Preliminary Wind-tunnel Tests of Silent Supersonic Technology Demonstrator

OpenAIRE

Makino, Yoshikazu; Ohira, Keisuke; Makimoto, Takuya; Mitomo, Toshiteru; 牧野, 好和; 大平, 啓介; 牧本, 卓也; 三友, 俊輝

2011-01-01

Effects of static aeroelastic deformation of a wind-tunnel test model on the aerodynamic characteristics are discussed in wind-tunnel tests in the preliminary design phase of the silent supersonic technology demonstrator (S3TD). The static aeroelastic deformation of the main wing is estimated for JAXA 2m x 2m transonic wind-tunnel and 1m x 1m supersonic wind-tunnel by a finite element method (FEM) structural analysis in which its structural model is tuned with the model deformation calibratio...

Simulation of flow over double-element airfoil and wind tunnel test for use in vertical axis wind turbine

International Nuclear Information System (INIS)

Chougule, Prasad; Nielsen, Søren R K

2014-01-01

Nowadays, small vertical axis wind turbines are receiving more attention due to their suitability in micro-electricity generation. There are few vertical axis wind turbine designs with good power curve. However, the efficiency of power extraction has not been improved. Therefore, an attempt has been made to utilize high lift technology for vertical axis wind turbines in order to improve power efficiency. High lift is obtained by double-element airfoil mainly used in aeroplane wing design. In this current work a low Reynolds number airfoil is selected to design a double-element airfoil blade for use in vertical axis wind turbine to improve the power efficiency. Double-element airfoil blade design consists of a main airfoil and a slat airfoil. Orientation of slat airfoil is a parameter of investigation in this paper and air flow simulation over double-element airfoil. With primary wind tunnel test an orientation parameter for the slat airfoil is initially obtained. Further a computational fluid dynamics (CFD) has been used to obtain the aerodynamic characteristics of double-element airfoil. The CFD simulations were carried out using ANSYS CFX software. It is observed that there is an increase in the lift coefficient by 26% for single-element airfoil at analysed conditions. The CFD simulation results were validated with wind tunnel tests. It is also observe that by selecting proper airfoil configuration and blade sizes an increase in lift coefficient can further be achieved

Field test of wake steering at an offshore wind farm

Directory of Open Access Journals (Sweden)

P. Fleming

2017-05-01

Full Text Available In this paper, a field test of wake-steering control is presented. The field test is the result of a collaboration between the National Renewable Energy Laboratory (NREL and Envision Energy, a smart energy management company and turbine manufacturer. In the campaign, an array of turbines within an operating commercial offshore wind farm in China have the normal yaw controller modified to implement wake steering according to a yaw control strategy. The strategy was designed using NREL wind farm models, including a computational fluid dynamics model, Simulator fOr Wind Farm Applications (SOWFA, for understanding wake dynamics and an engineering model, FLOw Redirection and Induction in Steady State (FLORIS, for yaw control optimization. Results indicate that, within the certainty afforded by the data, the wake-steering controller was successful in increasing power capture, by amounts similar to those predicted from the models.

Prognostic value of p53, c-ErbB2 and tunel data in upper urothelial carcinoma associated with Balkan nephropathy

Directory of Open Access Journals (Sweden)

Savin Marina

2014-01-01

Full Text Available A characteristic tumor suppressor protein 53 (p53 mutational profile of genotoxic action of aristolochic acid was identified in the upper urothelial carcinoma (UUTT associated with Balkan nephropathy (BEN. In the present study, we examined the prognostic value of tissue-based molecular markers in overall-survival (OS risk after surgical treatment of UUTT, adjusted for gender, age and urological characteristics in 32 patients with BEN. Immunohistochemical examination of p53, the proliferation cell nuclear antigen (PCNA, the human epidermal growth factor receptor 2 (c-ErbB2; also known as HER-2/neu proto-oncogene and the in situ terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL assay for apoptosis detection were used to examine serial tumor sections. The median OS-time was 60 months for UUTT operation; the mortality rate (18.7% was related to (new disease (reoccurrence or invasion in 12-216 months. High-grade (p=0.029, TUNEL>0.36%+ cells (p=0.010, and c-ErbB2+ cells (p=0.014 can define the risk of tumor invasion. Patients with Balkan nephropathy that develop UUTT at a stage greater than pT1 (with apoptosis TUNEL+ cells >0.36% and p53+ cells greater than 10% were at high risk of poor-OS after the tumor surgery (h(x=6.35; p=0.045. The obtained data present evidence for p53, cErbB2 and apoptosis deregulation, as a result of environmental toxin action. This is the first report of molecular biomarker linkage with OS for BEN-associated UUTT.

Wind-tunnel development of an SR-71 aerospike rocket flight test configuration

Science.gov (United States)

Smith, Stephen C.; Shirakata, Norm; Moes, Timothy R.; Cobleigh, Brent R.; Conners, Timothy H.

1996-01-01

A flight experiment has been proposed to investigate the performance of an aerospike rocket motor installed in a lifting body configuration. An SR-71 airplane would be used to carry the aerospike configuration to the desired flight test conditions. Wind-tunnel tests were completed on a 4-percent scale SR-71 airplane with the aerospike pod mounted in various locations on the upper fuselage. Testing was accomplished using sting and blade mounts from Mach 0.6 to Mach 3.2. Initial test objectives included assessing transonic drag and supersonic lateral-directional stability and control. During these tests, flight simulations were run with wind-tunnel data to assess the acceptability of the configurations. Early testing demonstrated that the initial configuration with the aerospike pod near the SR-71 center of gravity was unsuitable because of large nosedown pitching moments at transonic speeds. The excessive trim drag resulting from accommodating this pitching moment far exceeded the excess thrust capability of the airplane. Wind-tunnel testing continued in an attempt to find a configuration suitable for flight test. Multiple configurations were tested. Results indicate that an aft-mounted model configuration possessed acceptable performance, stability, and control characteristics.

Power Performance Verification of a Wind Farm Using the Friedman’s Test

Science.gov (United States)

Hernandez, Wilmar; López-Presa, José Luis; Maldonado-Correa, Jorge L.

2016-01-01

In this paper, a method of verification of the power performance of a wind farm is presented. This method is based on the Friedman’s test, which is a nonparametric statistical inference technique, and it uses the information that is collected by the SCADA system from the sensors embedded in the wind turbines in order to carry out the power performance verification of a wind farm. Here, the guaranteed power curve of the wind turbines is used as one more wind turbine of the wind farm under assessment, and a multiple comparison method is used to investigate differences between pairs of wind turbines with respect to their power performance. The proposed method says whether the power performance of the specific wind farm under assessment differs significantly from what would be expected, and it also allows wind farm owners to know whether their wind farm has either a perfect power performance or an acceptable power performance. Finally, the power performance verification of an actual wind farm is carried out. The results of the application of the proposed method showed that the power performance of the specific wind farm under assessment was acceptable. PMID:27271628

Power Performance Verification of a Wind Farm Using the Friedman’s Test

Directory of Open Access Journals (Sweden)

Wilmar Hernandez

2016-06-01

Full Text Available In this paper, a method of verification of the power performance of a wind farm is presented. This method is based on the Friedman’s test, which is a nonparametric statistical inference technique, and it uses the information that is collected by the SCADA system from the sensors embedded in the wind turbines in order to carry out the power performance verification of a wind farm. Here, the guaranteed power curve of the wind turbines is used as one more wind turbine of the wind farm under assessment, and a multiple comparison method is used to investigate differences between pairs of wind turbines with respect to their power performance. The proposed method says whether the power performance of the specific wind farm under assessment differs significantly from what would be expected, and it also allows wind farm owners to know whether their wind farm has either a perfect power performance or an acceptable power performance. Finally, the power performance verification of an actual wind farm is carried out. The results of the application of the proposed method showed that the power performance of the specific wind farm under assessment was acceptable.

Design and preliminary testing of a MEMS microphone phased array for aeroacoustic testing of a small-scale wind turbine airfoil

Energy Technology Data Exchange (ETDEWEB)

Bale, A.; Orlando, S.; Johnson, D. [Waterloo Univ., ON (Canada). Wind Energy Group

2010-07-01

One of the barriers preventing the widespread utilization of wind turbines is the audible sound that they produce. Developing quieter wind turbines will increase the amount of available land onto which wind farms can be built. Noise emissions from wind turbines can be attributed to the aerodynamic effects between the turbine blades and the air surrounding them. A dominant source of these aeroacoustic emissions from wind turbines is known to originate at the trailing edges of the airfoils. This study investigated the flow physics of noise generation in an effort to reduce noise from small-scale wind turbine airfoils. The trailing edge noise was studied on scale-models in wind tunnels and applied to full scale conditions. Microphone phased arrays are popular research tools in wind tunnel aeroacoustic studies because they can measure and locate noise sources. However, large arrays of microphones can be prohibitively expensive. This paper presented preliminary testing of micro-electrical mechanical system (MEMS) microphones in phased arrays for aeroacoustic testing on a small wind turbine airfoil. Preliminary results showed that MEMS microphones are an acceptable low-cost alternative to costly condenser microphones. 19 refs., 1 tab., 11 figs.

Materials of large wind turbine blades: Recent results in testing and modeling

DEFF Research Database (Denmark)

Mishnaevsky, Leon; Brøndsted, Povl; Nijssen, Rogier

2012-01-01

The reliability of rotor blades is the pre-condition for the development and wide use of large wind turbines. In order to accurately predict and improve the wind turbine blade behavior, three main aspects of the reliability and strength of rotor blades were considered: (i) development of methods...... of the effect of the microstructure of wind turbine blade composites on their strength and ways of microstructural optimization of the materials. By testing reference coupons, the effect of testing parameters (temperature and frequency) on the lifetime of blade composites was investigated, and the input data...... clustering, misalignments, interface properties and other factors on the strength and lifetime of the wind turbine blade materials were investigated in the micromechanical finite element simulations. The results described in this paper stem from the Rotor Structure and Materials task of the UPWIND project...

The 'Guetsch' Alpine wind power test site; Alpine Test Site Guetsch. Handbuch und Fachtagung

Energy Technology Data Exchange (ETDEWEB)

Cattin, R.

2008-12-15

This final report for the Swiss Federal Office of Energy (SFOE) takes a look at the influence of icing-up on the operation of wind turbines in mountainous areas. Within the Swiss research project 'Alpine Test Site Guetsch', extensive icing studies were carried out at the Guetsch site near Andermatt, Switzerland. This document deals with the following subjects: Information about ice formation on structures, in particular with respect to wind turbines, standards and international research activities, wind measurements under icing-up conditions, estimation of the frequency of icing-up conditions, effects of icing-up on wind turbines, ice detection, measures available for de-icing and anti-icing as well as ice throw. A list of factors to be taken into account by the planners and operators of wind turbines in alpine environments is presented.

Design, fabrication, and test of a composite material wind turbine rotor blade

Science.gov (United States)

Griffee, D. G., Jr.; Gustafson, R. E.; More, E. R.

1977-01-01

The aerodynamic design, structural design, fabrication, and structural testing is described for a 60 foot long filament wound, fiberglass/epoxy resin matrix wind turbine rotor blade for a 125 foot diameter, 100 kW wind energy conversion system. One blade was fabricated which met all aerodynamic shape requirements and was structurally capable of operating under all specified design conditions. The feasibility of filament winding large rotor blades was demonstrated.

First International Workshop on Grid Simulator Testing of Wind Turbine

Science.gov (United States)

utilities to exchange knowledge, discuss experiences, and identify needs in wind power grid compliance , multi-megawatt power electronic grid simulator systems capable of many types of grid compliance testing renewable energy technologies. Knowledge from the workshop will help guide the research and testing

Manufacturing and preliminary tests of a 12 T ''wind and react'' coil

International Nuclear Information System (INIS)

Corte, A. della; Pasotti, G.; Sacchetti, N.; Spadoni, M.; Oliva, A.B.; Penco, R.; Parodi, S.; Valle, N.; Specking, W.

1994-01-01

As already reported ENEA is engaged in the realization of a 12 T wind and react Nb 3 Sn coil, a subsize magnet designed to simulate many technological problems to be faced in NET-ITER magnets. EM-LMI and Ansaldo are the industrial partners in this project. A preliminary winding has been built and successfully tested. This winding has been cut in pieces and carefully inspected to be sure that the impregnation process after the heat treatment works well. No particular flaws have been detected. Then manufacturing of the 12 T magnet has been started and completed in about three months. Heat treatment, impregnation and electrical tests at 300 K have been successfully performed and the magnet is now ready for final tests. In order to obtain the most significant scientific and technological information from this magnet, the original test program (insertion of the coil in the SULTAN facility) has been modified according to a decision of the Fusion Technology Steering Committee (FTSC) of EURATOM. Details of the new test programs are given in the paper

Design and testing of a deformable wind turbine blade control surface

International Nuclear Information System (INIS)

Daynes, S; Weaver, P M

2012-01-01

Wind tunnel tests were conducted on a 1.3 m chord NACA 63–418 blade section fitted with an adaptive trailing edge flap. The 20% chord flap had an aramid honeycomb core covered with a silicone skin and was actuated using servo motors. The honeycomb core had a high stiffness in the thickness direction but was compliant in chordwise bending. These anisotropic properties offer a potential solution for the conflicting design requirements found in morphing trailing edge structures. Static and dynamic tests were performed up to a Reynolds number of 5.4 × 10 6 . The tests showed that deflecting the flap from − 10° to + 10° changes the blade section lift coefficient by 1.0 in non-stalled conditions. Dynamic tests showed the flap to be capable of operating up to 9° s −1 using a 15 V power supply. A two-dimensional static aeroelastic model of the morphing flap was developed to analyse strains, predict actuator requirements and study fluid–structure interaction effects. The model was used to conduct parametric studies to further improve the flap design. Potential applications include wind turbine blade load alleviation and increased wind energy capture. (paper)

Study on Determination Method of Fatigue Testing Load for Wind Turbine Blade

Science.gov (United States)

Liao, Gaohua; Wu, Jianzhong

2017-07-01

In this paper, the load calculation method of the fatigue test was studied for the wind turbine blade under uniaxial loading. The characteristics of wind load and blade equivalent load were analyzed. The fatigue property and damage theory of blade material were studied. The fatigue load for 2MW blade was calculated by Bladed, and the stress calculated by ANSYS. Goodman modified exponential function S-N curve and linear cumulative damage rule were used to calculate the fatigue load of wind turbine blades. It lays the foundation for the design and experiment of wind turbine blade fatigue loading system.

European wind turbine procedure development blade test methods and techniques

Energy Technology Data Exchange (ETDEWEB)

Bulder, B H; Dam, J J.D. van; Delft, D R.V. van [and others

1999-03-01

In this paper the preliminary results obtained by performing the second task of the `European Wind Turbine Testing Procedure Development` project are presented. This project is performed within and with financial support of the Standards, Measurements and Testing programme of the European Commission. (au)

Wind Turbine Drivetrain Condition Monitoring During GRC Phase 1 and Phase 2 Testing

Energy Technology Data Exchange (ETDEWEB)

Sheng, S.; Link, H.; LaCava, W.; van Dam, J.; McNiff, B.; Veers, P.; Keller, J.; Butterfield, S.; Oyague, F.

2011-10-01

This report will present the wind turbine drivetrain condition monitoring (CM) research conducted under the phase 1 and phase 2 Gearbox Reliability Collaborative (GRC) tests. The rationale and approach for this drivetrain CM research, investigated CM systems, test configuration and results, and a discussion on challenges in wind turbine drivetrain CM and future research and development areas, will be presented.

A study on the dryness judgement criterion for leak test in water-cooled generator stator windings

International Nuclear Information System (INIS)

Kim, Hee Soo; Bae, Yong Chae; Lee, Wook Ryun; Lee, Doo Young; Cho, Sung Won

2009-01-01

The complete dryness of stator inside is a necessary and sufficient condition for leak test. Microcracks by high cycle fatigue due to operation are generated in stator windings and they are interrupted by water molecules during leak test. For this reason, during leak test, the wrong value is indicated as follows: There are no leaks in stator windings. Generator manufacturers presents unique dryness judgement criteria for leak test but actually any criteria never indicate accurate dryness point for leak test. The reason is that stator winding has a complexity of structure and absence of an effective dryness equipment in power plant. In this paper, dryness judgement criterion to judge if stator winding inside is dried completely is proposed and is testified experimentally.

Design and field testing of Savonius wind pump in East Africa

International Nuclear Information System (INIS)

Rabah, K.V.O.; Osawa, B.M.

1995-04-01

We present here improvements in the wind-scoop geometry and efficiency of a double-stack Savonius rotor, developed through a series of wind tunnel and field testing in East Africa. On an aerodynamic performance basis, the Savonius rotor cannot generally compete with other types of wind turbines. This is entirely due to its mode of operation. Unlike its counter-parts that operate by rotating around a horizontal axis, it rotates around a vertical axis. This has the unfortunate effect of lowering its efficiency, but it has several compensating factors. Its main advantages are that it has better starting torque performance with operating characteristics independent of the wind direction. In addition, it is simple in structure and the fabrication technology required is less sophisticated when compared to similar types of windmills. This makes it a suitable system for small scale applications in wind energy conversion; especially in remote rural regions in developing countries. (author). 8 refs, 5 figs

Simulation of flow over double-element airfoil and wind tunnel test for use in vertical axis wind turbine

DEFF Research Database (Denmark)

Chougule, Prasad; Nielsen, Søren R.K.

2014-01-01

been made to utilize high lift technology for vertical axis wind turbines in order to improve power efficiency. High lift is obtained by double-element airfoil mainly used in aeroplane wing design. In this current work a low Reynolds number airfoil is selected to design a double-element airfoil blade...... for use in vertical axis wind turbine to improve the power efficiency. Double-element airfoil blade design consists of a main airfoil and a slat airfoil. Orientation of slat airfoil is a parameter of investigation in this paper and air flow simulation over double-element airfoil. With primary wind tunnel...... that there is an increase in the lift coefficient by 26% for single-element airfoil at analysed conditions. The CFD simulation results were validated with wind tunnel tests. It is also observe that by selecting proper airfoil configuration and blade sizes an increase in lift coefficient can further be achieved....

Wind tunnel tests of a deep seabed penetrator model

International Nuclear Information System (INIS)

Visintini, L.; Murray, C.N.

1991-01-01

C.C.R. Euratom Ispra are currently involved in studies on the possibility of storing radioactive wastes in deep ocean sediment beds. The report summarizes the results of wind tunnel tests performed in March 1985 on a 1:2.5 scale model of a European Standard Penetrator in Aermacchi low speed wind tunnel. Tests covered the measurement of overall fluid dynamic forces at varying angle of attack and measurement of unsteady pressures acting on the instrumentation head protruding in the penetrator's wake. Overall force coefficients were found to be in good agreement with predictions. Unsteady pressures were found to be much smaller than expected so that no mechanical damage to instrumentation is to be foreseen even at the high dynamic pressures typical of the penetrator moving into water. The present work has been undertaken under contract 2450-84-08 ED ISP I of C.C.R. EURATOM ISPRA

Special Tests for the Power Electronic Converters of Wind Turbine Generators

DEFF Research Database (Denmark)

Helle, Lars; Senturk, Osman Selcuk; Teodorescu, Remus

2011-01-01

-level medium-voltage source converter topologies, of the 3L-ANPC-VSC and 3L-HB-VSC type, are considered in the paper. Both converters employ press-pack IGBT-diode pairs and interface a 6 MW wind turbine to a medium voltage grid. The power loss and thermal model data applicable for both grid and generator......Power electronic converters for wind turbines are characterized by high specific power density and high reliability. Special tests for such converters are performed in order to determine the power loss and thermal models, which are dependent of the load profile and converter structure. Two multi......-side VSCs is used to estimate the switch junction temperatures through the simulation of wind turbine grid interface operation. A discussion of the power density and reliability of the grid-side VSCs with respect to press-pack switches, gate driver, and cooling plate is included. A test set-up for a single...

Power Performance Test Report for the U.S. Department of Energy 1.5-Megawatt Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Mendoza, Ismael [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hur, Jerry [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Thao, Syhoune [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Curtis, Amy [Windward Engineering, Santa Barbara, CA (United States)

2015-08-11

The U.S. Department of Energy (DOE) acquired and installed a 1.5-megawatt (MW) wind turbine at the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL). This turbine (hereafter referred to as the DOE 1.5) is envisioned to become an integral part of the research initiatives for the DOE Wind Program, such as Atmosphere to Electrons (A2e). A2e is a multiyear DOE research initiative targeting significant reductions in the cost of wind energy through an improved understanding of the complex physics governing wind flow into and through wind farms. For more information, visit http://energy.gov/eere/wind/atmosphere-electrons. To validate new and existing high-fidelity simulations, A2e must deploy several experimental measurement campaigns across different scales. Proposed experiments include wind tunnel tests, scaled field tests, and large field measurement campaigns at operating wind plants. Data of interest includes long-term atmospheric data sets, wind plant inflow, intra-wind plant flows (e.g., wakes), and rotor loads measurements. It is expected that new, high-fidelity instrumentation will be required to successfully collect data at the resolutions required to validate the high-fidelity simulations.

Power Quality Test Report for the U.S. Department of Energy 1.5-Megawatt Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Mendoza, Ismael [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hur, Jerry [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Thao, Syhoune [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2015-08-20

The U.S. Department of Energy (DOE) acquired and installed a 1.5-megawatt (MW) wind turbine at the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory. This turbine (hereafter referred to as the DOE 1.5) is envisioned to become an integral part of the research initiatives for the DOE Wind Program, such as Atmosphere to Electrons (A2e). A2e is a multiyear DOE research initiative targeting significant reductions in the cost of wind energy through an improved understanding of the complex physics governing wind flow into and through wind farms. For more information, visit http://energy.gov/eere/wind/atmosphere-electrons. To validate new and existing high-fidelity simulations, A2e must deploy several experimental measurement campaigns across different scales. Proposed experiments include wind tunnel tests, scaled field tests, and large field measurement campaigns at operating wind plants. Data of interest includes long-term atmospheric data sets, wind plant inflow, intra-wind plant flows (e.g., wakes), and rotor loads measurements. It is expected that new, high-fidelity instrumentation will be required to successfully collect data at the resolutions required to validate the high-fidelity simulations.

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

Energy Technology Data Exchange (ETDEWEB)

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

2001-04-19

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

Investigation on wind turbine wakes: wind tunnel tests and field experiments with LIDARs

Science.gov (United States)

Iungo, Giacomo; Wu, Ting; Cöeffé, Juliette; Porté-Agel, Fernando; WIRE Team

2011-11-01

An investigation on the interaction between atmospheric boundary layer flow and wind turbines is carried out with wind tunnel and LIDAR measurements. The former were carried out using hot-wire anemometry and multi-hole pressure probes in the wake of a three-bladed miniature wind turbine. The wind turbine wake is characterized by a strong velocity defect in the proximity of the rotor, and its recovery is found to depend on the characteristics of the incoming atmospheric boundary layer (mean velocity and turbulence intensity profiles). Field experiments were performed using three wind LIDARs. Bi-dimensional scans are performed in order to analyse the wake wind field with different atmospheric boundary layer conditions. Furthermore, simultaneous measurements with two or three LIDARs allow the reconstruction of multi-component velocity fields. Both LIDAR and wind tunnel measurements highlight an increased turbulence level at the wake boundary for heights comparable to the top-tip of the blades; this flow feature can produce dangerous fatigue loads on following wind turbines.

Dual-axis resonance testing of wind turbine blades

Science.gov (United States)

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.

Test Plan for Rotary Mode Core Sample Truck Grapple Hoist Level Wind System

International Nuclear Information System (INIS)

BOGER, R.M.

1999-01-01

A Grapple Hoist Assembly is currently used on the Rotary Mode Core Sampling Trucks (RMCSTs) to actuate the sampler and retrieve the pintle rod during sampling operations. The hoist assembly includes a driven drum approximately two inches wide and six inches in diameter that rotates to pay out or reel in the 5/32-in. cable The current Grapple Hoist Assembly, detailed on drawing H-2-690057, is prone to ''bird nesting'' the cable on the drum. ''Bird nesting'' is a condition in which the cable does not wind onto the drum in a uniformly layered manner, but winds in a random fashion where the cable essentially ''piles up'' inappropriately on the drum and, on some occasions, winds on the drum drive shaft. A system to help control this ''bird nesting'' problem has been designed as an addition to the existing components of the Grapple Hoist Assembly. The new design consists of a mechanism that is timed with, and driven by, the shaft that drives the drum. This mechanism traverses back and forth across the width of the drum to lay the cable on the drum in a uniformly layered manner. This test plan establishes the acceptance criteria, test procedure and test conditions It also describes the test apparatus necessary to verify the adequacy of the level wind system design. The test is defined as qualification testing (LMHC 1999b) and as such will be performed at conditions beyond the parameters that the Grapple Hoist Assembly is allowed to operate by the Safety Equipment List (SEL)(LMHC 1998)

Test Plan for Rotary Mode Core Sample Truck Grapple Hoist Level Wind System

International Nuclear Information System (INIS)

BOGER, R.M.

1999-01-01

A Grapple Hoist Assembly is currently used on the Rotary Mode Core Sampling Trucks (RMCSTs) to actuate the sampler and retrieve the pintle rod during sampling operations. The hoist assembly includes a driven drum approximately two inches wide and six inches in diameter that rotates to pay out or reel in the 5/32-in. cable. The current Grapple Hoist Assembly, detailed on drawing H-2-690057, is prone to ''bird nesting'' the cable on the drum. ''Bird nesting'' is a condition in which the cable does not wind onto the drum in a uniformly layered manner, but winds in a random fashion where the cable essentially ''piles up'' inappropriately on the drum and, on some occasions, winds on the drum drive shaft. A system to help control this ''bird nesting'' problem has been designed as an addition to the existing components of the Grapple Hoist Assembly. The new design consists of a mechanism that is timed with, and driven by, the shaft that drives the drum. This mechanism traverses back and forth across the width of the drum to lay the cable on the drum in a uniformly layered manner. This test plan establishes the acceptance criteria, test procedure and test conditions. It also describes the test apparatus necessary to verify the adequacy of the level wind system design. The test is defined as qualification testing (LMHC 1999b) and as such will be performed at conditions beyond the parameters that the Grapple Hoist Assembly is allowed to operate by the Safety Equipment List

Wind Power Today: 1998 Wind Energy Program Highlights

Energy Technology Data Exchange (ETDEWEB)

Tromly, K.

1999-06-17

The US Department of Energy's Office of Energy Efficiency and Renewable Energy manages the Federal Wind Energy Program. The mission of the program is to help the US wind industry to complete the research, testing, and field verification needed to fully develop advanced wind technologies that will lead the world in cost-effectiveness and reliability. This publication, printed annually, provides a summary of significant achievements in wind energy made during the previous calendar year. Articles include wind energy in the Midwest, an Alaskan wind energy project, the US certification program, structural testing, and the federal program in review.

Using partial safety factors in wind turbine design and testing

Energy Technology Data Exchange (ETDEWEB)

Musial, W.D. [National Renewable Energy Lab., Golden, CO (United States)

1997-12-31

This paper describes the relationship between wind turbine design and testing in terms of the certification process. An overview of the current status of international certification is given along with a description of limit-state design basics. Wind turbine rotor blades are used to illustrate the principles discussed. These concepts are related to both International Electrotechnical Commission and Germanischer Lloyd design standards, and are covered using schematic representations of statistical load and material strength distributions. Wherever possible, interpretations of the partial safety factors are given with descriptions of their intended meaning. Under some circumstances, the authors` interpretations may be subjective. Next, the test-load factors are described in concept and then related to the design factors. Using technical arguments, it is shown that some of the design factors for both load and materials must be used in the test loading, but some should not be used. In addition, some test factors not used in the design may be necessary for an accurate test of the design. The results show that if the design assumptions do not clearly state the effects and uncertainties that are covered by the design`s partial safety factors, outside parties such as test labs or certification agencies could impose their own meaning on these factors.

Wind turbine blade testing system using base excitation

Science.gov (United States)

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).

Application of Rapid Prototyping Methods to High-Speed Wind Tunnel Testing

Science.gov (United States)

Springer, A. M.

1998-01-01

This study was undertaken in MSFC's 14-Inch Trisonic Wind Tunnel to determine if rapid prototyping methods could be used in the design and manufacturing of high speed wind tunnel models in direct testing applications, and if these methods would reduce model design/fabrication time and cost while providing models of high enough fidelity to provide adequate aerodynamic data, and of sufficient strength to survive the test environment. Rapid prototyping methods utilized to construct wind tunnel models in a wing-body-tail configuration were: fused deposition method using both ABS plastic and PEEK as building materials, stereolithography using the photopolymer SL-5170, selective laser sintering using glass reinforced nylon, and laminated object manufacturing using plastic reinforced with glass and 'paper'. This study revealed good agreement between the SLA model, the metal model with an FDM-ABS nose, an SLA nose, and the metal model for most operating conditions, while the FDM-ABS data diverged at higher loading conditions. Data from the initial SLS model showed poor agreement due to problems in post-processing, resulting in a different configuration. A second SLS model was tested and showed relatively good agreement. It can be concluded that rapid prototyping models show promise in preliminary aerodynamic development studies at subsonic, transonic, and supersonic speeds.

Wind power communication design and implementation of test environment for IEC61850/UCA2

Energy Technology Data Exchange (ETDEWEB)

Johnsson, A.; Svensson, J.

2002-04-01

Elforsk has sponsored a joint Swedish-Danish project aiming at finding and recommend a common solution for communication with wind power plants. The first stage of the work resulted in a requirement specification Functional Requirements on Communication System for Wind Turbine Applications. During the project a number of possible communication solutions were identified. The two most promising solutions have been tested in order to verify to what extent they fulfil the requirements in the specification. A version of the IEC 61850 standard based on the communication protocol MMS, has been tested at a wind power plant at Gotland, Sweden, and an OPC-interface has been tested in Denmark. This report includes a description of the design choices made for the test implementation of MMS, as well as a detailed description of the implementation of the IEC 61850/UCA2 software including information models and information exchange services. (BA)

Small wind turbine performance evaluation using field test data and a coupled aero-electro-mechanical model

Science.gov (United States)

Wallace, Brian D.

A series of field tests and theoretical analyses were performed on various wind turbine rotor designs at two Penn State residential-scale wind-electric facilities. This work involved the prediction and experimental measurement of the electrical and aerodynamic performance of three wind turbines; a 3 kW rated Whisper 175, 2.4 kW rated Skystream 3.7, and the Penn State designed Carolus wind turbine. Both the Skystream and Whisper 175 wind turbines are OEM blades which were originally installed at the facilities. The Carolus rotor is a carbon-fiber composite 2-bladed machine, designed and assembled at Penn State, with the intent of replacing the Whisper 175 rotor at the off-grid system. Rotor aerodynamic performance is modeled using WT_Perf, a National Renewable Energy Laboratory developed Blade Element Momentum theory based performance prediction code. Steady-state power curves are predicted by coupling experimentally determined electrical characteristics with the aerodynamic performance of the rotor simulated with WT_Perf. A dynamometer test stand is used to establish the electromechanical efficiencies of the wind-electric system generator. Through the coupling of WT_Perf and dynamometer test results, an aero-electro-mechanical analysis procedure is developed and provides accurate predictions of wind system performance. The analysis of three different wind turbines gives a comprehensive assessment of the capability of the field test facilities and the accuracy of aero-electro-mechanical analysis procedures. Results from this study show that the Carolus and Whisper 175 rotors are running at higher tip-speed ratios than are optimum for power production. The aero-electro-mechanical analysis predicted the high operating tip-speed ratios of the rotors and was accurate at predicting output power for the systems. It is shown that the wind turbines operate at high tip-speeds because of a miss-match between the aerodynamic drive torque and the operating torque of the wind

Documentation and archiving of the Space Shuttle wind tunnel test data base. Volume 2: User's Guide to the Archived Data Base

Science.gov (United States)

Romere, Paul O.; Brown, Steve Wesley

1995-01-01

Development of the Space Shuttle necessitated an extensive wind tunnel test program, with the cooperation of all the major wind tunnels in the United States. The result was approximately 100,000 hours of Space Shuttle wind tunnel testing conducted for aerodynamics, heat transfer, and structural dynamics. The test results were converted into Chrysler DATAMAN computer program format to facilitate use by analysts, a very cost effective method of collecting the wind tunnel test results from many test facilities into one centralized location. This report provides final documentation of the Space Shuttle wind tunnel program. The two-volume set covers the evolution of Space Shuttle aerodynamic configurations and gives wind tunnel test data, titles of wind tunnel data reports, sample data sets, and instructions for accessing the digital data base.

Full-Scale Field Test of a Blade-Integrated Dual-Telescope Wind Lidar

DEFF Research Database (Denmark)

Pedersen, Anders Tegtmeier; Sjöholm, Mikael; Angelou, Nikolas

. Simultaneously, data regarding wind speed, rotational speed, and pitch angle recorded by the turbine was logged as well as data from a nearby met mast. The encouraging results of this first campaign include wind speed measurements at 20 Hz data rate along the rotor plane, acquired during the co...... in the top and bottom of the rotor plane. Conclusion We present here what we believe is the first successful wind speed measurements from a dual-telescope lidar installed on the blade of an operating wind turbine. The full-scale field test performed in the summer of 2012 has clearly demonstrated...... the possibility of integrating lidar telescopes into turbine blades as well as the capability of the lidar to measure the required wind speeds and to operate in the challenging environment of a rotating spinner and vibrating blade. The use of two separate telescopes allows a direct measurement of the blade’s AOA...

Time-Varying Dynamic Properties of Offshore Wind Turbines Evaluated by Modal Testing

DEFF Research Database (Denmark)

Damgaard, Mads; Andersen, J. K. F.; Ibsen, Lars Bo

2014-01-01

resonance of the wind turbine structure. In this paper, free vibration tests and a numerical Winkler type approach are used to evaluate the dynamic properties of a total of 30 offshore wind turbines located in the North Sea. Analyses indicate time-varying eigenfrequencies and damping ratios of the lowest...... structural eigenmode. Isolating the oscillation oil damper performance, moveable seabed conditions may lead to the observed time dependency....

Unsteady Aerodynamics Experiment Phase VI: Wind Tunnel Test Configurations and Available Data Campaigns

Energy Technology Data Exchange (ETDEWEB)

Hand, M. M.; Simms, D. A.; Fingersh, L. J.; Jager, D. W.; Cotrell, J. R.; Schreck, S.; Larwood, S. M.

2001-12-01

The primary objective of the insteady aerodynamics experiment was to provide information needed to quantify the full-scale, three-dimensional aerodynamic behavior of horizontal-axis wind turbines. This report is intended to familiarize the user with the entire scope of the wind tunnel test and to support the use of the resulting data.

Validation of US3D for Capsule Aerodynamics using 05-CA Wind Tunnel Test Data

Science.gov (United States)

Schwing, Alan

2012-01-01

Several comparisons of computational fluid dynamics to wind tunnel test data are shown for the purpose of code validation. The wind tunnel test, 05-CA, uses a 7.66% model of NASA's Multi-Purpose Crew Vehicle in the 11-foot test section of the Ames Unitary Plan Wind tunnel. A variety of freestream conditions over four Mach numbers and three angles of attack are considered. Test data comparisons include time-averaged integrated forces and moments, time-averaged static pressure ports on the surface, and Strouhal Number. The applicability of the US3D code to subsonic and transonic flow over a bluff body is assessed on a comprehensive data set. With close comparison, this work validates US3D for highly separated flows similar to those examined here.

Testing and Commissioning of Lillgrund Wind Farm. Lillgrund Pilot Project

Energy Technology Data Exchange (ETDEWEB)

Larsen, Poul Erik; Larsson, Aake; Jeppsson, Joakim; Toernkvist, Mattias (ed.) (Vattenfall Vindkraft AB, Stockholm (Sweden))

2009-04-15

This report gives an overview of the tests carried out in the Lillgrund project. The report covers factory tests, site tests and the performance tests, which can be carried out during the defects liability period. The report describes tests relevant for the wind turbine generators, the electrical system and the foundations. On the whole, the Lillgrund test results have been satisfactory. One of the more problematic issues experienced were when the foundation interface verification showed that the bolts were not meeting the height requirements. Since this shortcoming was detected relatively early in the project life, it was possible to correct the misalignment and keep the additional costs to a minimum. From a management point of view, this highlighted the importance of clear and unambiguous interface specifications and to make sure that the project has a proper interface management function. According to the Contract, Vattenfall has the right to verify a number of performance parameters during the 5-year defect liability period. The performance tests include availability, power curve, electrical system losses and acoustic noise levels. The contract specifies the test criteria, the test methods and procedures and the penalty if the tests result in undesirable levels. In some cases, there is a financial incentive for the supplier if the tests show that the wind farm is performing better than stipulated in the contract. Lillgrund has performed very well thus far and Vattenfall has determined that the contractual performance requirements are being met. Vattenfall has, therefore, not requested to carry out any of these elective Performance Tests

A New Position Measurement System Using a Motion-Capture Camera for Wind Tunnel Tests

Directory of Open Access Journals (Sweden)

Yousok Kim

2013-09-01

Full Text Available Considering the characteristics of wind tunnel tests, a position measurement system that can minimize the effects on the flow of simulated wind must be established. In this study, a motion-capture camera was used to measure the displacement responses of structures in a wind tunnel test, and the applicability of the system was tested. A motion-capture system (MCS could output 3D coordinates using two-dimensional image coordinates obtained from the camera. Furthermore, this remote sensing system had some flexibility regarding lab installation because of its ability to measure at relatively long distances from the target structures. In this study, we performed wind tunnel tests on a pylon specimen and compared the measured responses of the MCS with the displacements measured with a laser displacement sensor (LDS. The results of the comparison revealed that the time-history displacement measurements from the MCS slightly exceeded those of the LDS. In addition, we confirmed the measuring reliability of the MCS by identifying the dynamic properties (natural frequency, damping ratio, and mode shape of the test specimen using system identification methods (frequency domain decomposition, FDD. By comparing the mode shape obtained using the aforementioned methods with that obtained using the LDS, we also confirmed that the MCS could construct a more accurate mode shape (bending-deflection mode shape with the 3D measurements.

Test Plan for Rotary Mode Core Sample Truck Grapple Hoist Level Wind System

Energy Technology Data Exchange (ETDEWEB)

BOGER, R.M.

1999-12-09

A Grapple Hoist Assembly is currently used on the Rotary Mode Core Sampling Trucks (RMCSTs) to actuate the sampler and retrieve the pintle rod during sampling operations. The hoist assembly includes a driven drum approximately two inches wide and six inches in diameter that rotates to pay out or reel in the 5/32-in. cable The current Grapple Hoist Assembly, detailed on drawing H-2-690057, is prone to ''bird nesting'' the cable on the drum. ''Bird nesting'' is a condition in which the cable does not wind onto the drum in a uniformly layered manner, but winds in a random fashion where the cable essentially ''piles up'' inappropriately on the drum and, on some occasions, winds on the drum drive shaft. A system to help control this ''bird nesting'' problem has been designed as an addition to the existing components of the Grapple Hoist Assembly. The new design consists of a mechanism that is timed with, and driven by, the shaft that drives the drum. This mechanism traverses back and forth across the width of the drum to lay the cable on the drum in a uniformly layered manner. This test plan establishes the acceptance criteria, test procedure and test conditions It also describes the test apparatus necessary to verify the adequacy of the level wind system design. The test is defined as qualification testing (LMHC 1999b) and as such will be performed at conditions beyond the parameters that the Grapple Hoist Assembly is allowed to operate by the Safety Equipment List (SEL)(LMHC 1998).

Wind tunnel testing of scaled models of a newly developed Darrieus-style vertical axis wind turbine with auxiliary straight blades

International Nuclear Information System (INIS)

Scungio, M.; Arpino, F.; Focanti, V.; Profili, M.; Rotondi, M.

2016-01-01

Highlights: • Wind tunnel investigations of Darrieus-style VAWT with auxiliary blades have been made. • Results have been compared with those from standard Darrieus VAWT. • Static and dynamic power and torque coefficients were measured and evaluated. • The auxiliary airfoils have demonstrated to give more torque at the lower wind speeds. • The proposed VAWT configuration is able to work in a wide range of wind speeds. - Abstract: Renewable sources of energy, needed because of the increasing price of fossil derivatives, global warming and energy market instabilities, have led to an increasing interest in wind energy. Among the different typologies, small scale Vertical Axis Wind Turbines (VAWT) present the greatest potential for off grid power generation at low wind speeds. In the present work, wind tunnel investigations about the performance of an innovative configuration of straight-blades Darrieus-style vertical axis micro wind turbine, specifically developed for small scale energy conversion at low wind speeds, has been made on scaled models. The micro turbine under investigation consists of three pairs of airfoils. Each pair consists of a main and auxiliary airfoil with different chord lengths. A standard Darrieus configuration, consisting of three single airfoils, was also tested for comparison. The experiments were conducted in a closed circuit open chamber wind tunnel facility available at the Laboratory of Industrial Measurements (LaMI) of the University of Cassino and Lazio Meridionale (UNICLAM). Measured data were reported in terms of dimensionless power and torque coefficients for dynamic performance analysis and static torque coefficient for static performance analysis. The adoption of auxiliary airfoils has demonstrated to give more dynamic torque at the lower wind speeds with respect to a standard Darrieus rotor, resulting in better performance for all the wind speeds considered. In terms of dynamic power coefficient, the standard Darrieus

Wind tunnel test IA300 analysis and results, volume 1

Science.gov (United States)

Kelley, P. B.; Beaufait, W. B.; Kitchens, L. L.; Pace, J. P.

1987-01-01

The analysis and interpretation of wind tunnel pressure data from the Space Shuttle wind tunnel test IA300 are presented. The primary objective of the test was to determine the effects of the Space Shuttle Main Engine (SSME) and the Solid Rocket Booster (SRB) plumes on the integrated vehicle forebody pressure distributions, the elevon hinge moments, and wing loads. The results of this test will be combined with flight test results to form a new data base to be employed in the IVBC-3 airloads analysis. A secondary objective was to obtain solid plume data for correlation with the results of gaseous plume tests. Data from the power level portion was used in conjunction with flight base pressures to evaluate nominal power levels to be used during the investigation of changes in model attitude, eleveon deflection, and nozzle gimbal angle. The plume induced aerodynamic loads were developed for the Space Shuttle bases and forebody areas. A computer code was developed to integrate the pressure data. Using simplified geometrical models of the Space Shuttle elements and components, the pressure data were integrated to develop plume induced force and moments coefficients that can be combined with a power-off data base to develop a power-on data base.

Wing configuration on Wind Tunnel Testing of an Unmanned Aircraft Vehicle

Science.gov (United States)

Daryanto, Yanto; Purwono, Joko; Subagyo

2018-04-01

Control surface of an Unmanned Aircraft Vehicle (UAV) consists of flap, aileron, spoiler, rudder, and elevator. Every control surface has its own special functionality. Some particular configurations in the flight mission often depend on the wing configuration. Configuration wing within flap deflection for takeoff setting deflection of flap 20° but during landing deflection of flap set on the value 40°. The aim of this research is to get the ultimate CLmax for take-off flap deflection setting. It is shown from Wind Tunnel Testing result that the 20° flap deflection gives optimum CLmax with moderate drag coefficient. The results of Wind Tunnel Testing representing by graphic plots show good performance as well as the stability of UAV.

Validation of a wind tunnel testing facility for blade surface pressure measurements

Energy Technology Data Exchange (ETDEWEB)

Fuglsang, P.; Antoniou, I.; Soerensen, N.N.; Madsen, H.A.

1998-04-01

This report concerns development and validation of a 2d testing facility for airfoil pressure measurements. The VELUX open jet wind tunnel was used with a test stand inserted. Reynolds numbers until 1.3 million were achieved with an airfoil chord of 0.45 m. The aerodynamic load coefficients were found from pressure distribution measurements and the total drag coefficient was calculated from wake rake measurements. Stationary inflow as well as dynamic inflow through pitching motion was possible. Wind tunnel corrections were applied for streamline curvature and down-wash. Even though the wind tunnel is not ideal for 2d testing, the overall quality of the flow was acceptable with a uniform flow field at the test stand position and a turbulence intensity of 1 % at the inlet of the test section. Reference values for free stream static and total pressure were found upstream of the test stand. The NACA 63-215 airfoil was tested and the results were compared with measurements from FFA and NACA. The measurements agreed well except for lift coefficient values at high angles of attack and the drag coefficient values at low angles of attack, that were slightly high. Comparisons of the measured results with numerical predictions from the XFOIL code and the EllipSys2D code showed good agreement. Measurements with the airfoil in pitching motion were carried out to study the dynamic aerodynamic coefficients. Steady inflow measurements at high angles of attack were used to investigate the double stall phenomenon. (au) EFP-94; EFP-95; EFP-97. 8 tabs., 82 ills., 16 refs.

An evaluation of the WindEye wind lidar

DEFF Research Database (Denmark)

Dellwik, Ebba; Sjöholm, Mikael; Mann, Jakob

Prevision of the wind field by remote sensing wind lidars has the potential to improve the performance of wind turbines. The functionality of a WindEye lidar developed by Windar Photonics A/S (Denmark) for the wind energy market was tested in a two months long field experiment. The WindEye sensor...... with a high accuracy during the whole campaign....

Wind tunnel tests on a one-foot diameter SR-7L propfan model

Science.gov (United States)

Aljabri, Abdullah S.

1987-01-01

Wind tunnel tests have been conducted on a one-foot diameter model of the SR-7L propfan in the Langley 16-Foot and 4 x 7 Meter Wind Tunnels as part of the Propfan Test Assessment (PTA) Program. The model propfan was sized to be used on a 1/9-scale model of the PTA testbed aircraft. The model propeller was tested in isolation and wing-mounted on the aircraft configuration at various Mach numbers and blade pitch angles. Agreement between data obtained from these tests and data from Hamilton Standard validate that the 1/9-scale propeller accurately simulates the aerodynamics of the SR-7L propfan. Predictions from an analytical computer program are presented and show good agreement with the experimental data.

New Method for Dual-Axis Fatigue Testing of Large Wind Turbine Blades Using Resonance Excitation and Spectral Loading

Energy Technology Data Exchange (ETDEWEB)

White, D.

2004-04-01

The blades of a wind turbine are generally considered to be the most critical component of the wind turbine system. The fundamental purpose of performing fatigue tests on wind turbine blades is to demonstrate that a blade, when manufactured to a certain set of specifications, has the prescribed reliability and service life. The purpose of the research conducted for this project is the advancement of knowledge and capabilities in the area of wind turbine blade fatigue testing.

Mechanical Loads Test Report for the U.S. Department of Energy 1.5-Megawatt Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Santos, Rick [Santos Wind Engineering Technologies, Inc., Portland, ME (United States); van Dam, Jeroen [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2015-07-16

The objective of the test was to obtain a baseline characterization of the mechanical loads of the DOE 1.5 wind turbine located at NREL. The test was conducted in accordance with the International Electrotechnical Commission (IEC) Technical Specification, IEC 61400-13 Wind Turbine Generator Systems – Part 13: Measurement of mechanical loads; First Edition 2001-06 [1]. The National Wind Technology Center (NWTC) at NREL conducted this test in accordance with its quality system procedures so that the final test report meets the full requirements of its accreditation by the American Association for Laboratory Accreditation (A2LA). NREL’s quality system requires that all applicable requirements specified by A2LA and International Standards Organization/IEC 17025 be met or to note any exceptions in the test report.

Development of a test facility for PV-Wind hybrid energy systems

Energy Technology Data Exchange (ETDEWEB)

Engin, Mustafa [Ege Univ., Izmir (Turkey). Ege Tech., Electronics Technolgy; Ege Univ., Izmir (Turkey). Solar Energy Inst.

2010-07-01

To quantify the potential for performance improvements of photovoltaic-wind hybrid energy systems, a test facility has been installed at the Solar Energy Institute, Ege University. Hybrid system consist of a wind turbine, PV array, battery, AC and DC loads, inverters, charge regulators and a data logging and control unit. The collected data are first conditioned using precision electronic circuits and then interfaced to a PC using a data logging unit. The LABVIEW program is used to further process, display and store the collected data in the PC disk. The proposed data logging and control unit permits the rapid system development and has the advantage of flexibility in the case of changes, while it can be easily extended for controlling the of photovoltaic-wind hybrid energy system operation. (orig.)

What scaling means in wind engineering: Complementary role of the reduced scale approach in a BLWT and the full scale testing in a large climatic wind tunnel

Science.gov (United States)

Flamand, Olivier

2017-12-01

Wind engineering problems are commonly studied by wind tunnel experiments at a reduced scale. This introduces several limitations and calls for a careful planning of the tests and the interpretation of the experimental results. The talk first revisits the similitude laws and discusses how they are actually applied in wind engineering. It will also remind readers why different scaling laws govern in different wind engineering problems. Secondly, the paper focuses on the ways to simplify a detailed structure (bridge, building, platform) when fabricating the downscaled models for the tests. This will be illustrated by several examples from recent engineering projects. Finally, under the most severe weather conditions, manmade structures and equipment should remain operational. What “recreating the climate” means and aims to achieve will be illustrated through common practice in climatic wind tunnel modelling.

Finite-element analysis and modal testing of a rotating wind turbine

Science.gov (United States)

Carne, T. G.; Lobitz, D. W.; Nord, A. R.; Watson, R. A.

1982-10-01

A finite element procedure, which includes geometric stiffening, and centrifugal and Coriolis terms resulting from the use of a rotating coordinate system, was developed to compute the mode shapes and frequencies of rotating structures. Special applications of this capability was made to Darrieus, vertical axis wind turbines. In a parallel development effort, a technique for the modal testing of a rotating vertical axis wind turbine is established to measure modal parameters directly. Results from the predictive and experimental techniques for the modal frequencies and mode shapes are compared over a wide range of rotational speeds.

Remote Sensing Wind and Wind Shear System.

Science.gov (United States)

Contents: Remote sensing of wind shear and the theory and development of acoustic doppler; Wind studies; A comparison of methods for the remote detection of winds in the airport environment; Acoustic doppler system development; System calibration; Airport operational tests.

NASA ERA Integrated CFD for Wind Tunnel Testing of Hybrid Wing-Body Configuration

Science.gov (United States)

Garcia, Joseph A.; Melton, John E.; Schuh, Michael; James, Kevin D.; Long, Kurt R.; Vicroy, Dan D.; Deere, Karen A.; Luckring, James M.; Carter, Melissa B.; Flamm, Jeffrey D.;

Wind tunnel testing to predict control room atmospheric dispersion factors

International Nuclear Information System (INIS)

Holmquist, L.J.; Harden, P.A.; Muraida, J.E.

1993-01-01

Recent concerns at Palisades about control room habitability in the event of a loss-of-coolant accident have led to an extensive effort to increase control room habitability margin. The heating, ventilating and air-conditioning (HVAC) system servicing the control room has the potential for unfiltered in-leakage through its normal outside air intake louvered isolation dampers during emergency mode. The current limiting control room habitability analysis allows for 1.2 x 10 -2 m 3 /s (25 ft 3 /min) unfiltered in-leakage into the control room envelope. This leakage value was not thought to be achievable with the existing as-built configuration. Repairing the system was considered as a potential solution; however, this would be costly and could negatively affect plant operation. In addition, the system would still be required to meet the low specified unfiltered in-leakage. A second approach to this problem was to determine the atmospheric dispersion factors (x/Q's) through a wind tunnel test using a scale model of Palisades. The results of the wind tunnel testing could yield more realistic x/Q's for control room habitability than previously employed methods. Palisades selected the wind tunnel study option based on its ease of implementation, realistic results, and low cost. More importantly, the results of the study could increase the allowable unfiltered in-leakage

Design and initial testing of a one-bladed 30-meter-diameter rotor on the NASA/DOE mod-O wind turbine

Science.gov (United States)

Corrigan, R. D.; Ensworth, C. B. F.

1986-01-01

The concept of a one-bladed horizontal-axis wind turbine has been of interest to wind turbine designers for many years. Many designs and economic analyses of one-bladed wind turbines have been undertaken by both United States and European wind energy groups. The analyses indicate significant economic advantages but at the same time, significant dynamic response concerns. In an effort to develop a broad data base on wind turbine design and operations, the NASA Wind Energy Project Office has tested a one-bladed rotor at the NASA/DOE Mod-O Wind Turbine Facility. This is the only known test on an intermediate-sized one-bladed rotor in the United States. The 15.2-meter-radius rotor consists of a tip-controlled blade and a counterweight assembly. A rigorous test series was conducted in the Fall of 1985 to collect data on rotor performance, drive train/generator dynamics, structural dynamics, and structural loads. This report includes background information on one-bladed rotor concepts, and Mod-O one-bladed rotor test configuration, supporting design analysis, the Mod-O one-blade rotor test plan, and preliminary test results.

Development and testing of improved statistical wind power forecasting methods.

Energy Technology Data Exchange (ETDEWEB)

Mendes, J.; Bessa, R.J.; Keko, H.; Sumaili, J.; Miranda, V.; Ferreira, C.; Gama, J.; Botterud, A.; Zhou, Z.; Wang, J. (Decision and Information Sciences); (INESC Porto)

2011-12-06

Wind power forecasting (WPF) provides important inputs to power system operators and electricity market participants. It is therefore not surprising that WPF has attracted increasing interest within the electric power industry. In this report, we document our research on improving statistical WPF algorithms for point, uncertainty, and ramp forecasting. Below, we provide a brief introduction to the research presented in the following chapters. For a detailed overview of the state-of-the-art in wind power forecasting, we refer to [1]. Our related work on the application of WPF in operational decisions is documented in [2]. Point forecasts of wind power are highly dependent on the training criteria used in the statistical algorithms that are used to convert weather forecasts and observational data to a power forecast. In Chapter 2, we explore the application of information theoretic learning (ITL) as opposed to the classical minimum square error (MSE) criterion for point forecasting. In contrast to the MSE criterion, ITL criteria do not assume a Gaussian distribution of the forecasting errors. We investigate to what extent ITL criteria yield better results. In addition, we analyze time-adaptive training algorithms and how they enable WPF algorithms to cope with non-stationary data and, thus, to adapt to new situations without requiring additional offline training of the model. We test the new point forecasting algorithms on two wind farms located in the U.S. Midwest. Although there have been advancements in deterministic WPF, a single-valued forecast cannot provide information on the dispersion of observations around the predicted value. We argue that it is essential to generate, together with (or as an alternative to) point forecasts, a representation of the wind power uncertainty. Wind power uncertainty representation can take the form of probabilistic forecasts (e.g., probability density function, quantiles), risk indices (e.g., prediction risk index) or scenarios

Application of Photoshop-based image analysis and TUNEL for the distribution and quantification of dexamethasone-induced apoptotic cells in rat thymus.

Science.gov (United States)

Hussar, Piret; Tokin, Ivan; Hussar, Ulo; Filimonova, Galina; Suuroja, Toivo

2006-01-01

The aim of the present study was to determine the target site cells in the rat thymus after exposure to the synthetic glucocorticoid, dexamethasone, at therapeutic doses. The findings of histology and histochemistry (Feulgen, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling--TUNEL) with quantification by computerized histomorphometry are described. A quantified investigation of apoptotic and mitotic thymic lymphocytes in 36 young adult Wistar rats was performed at 1-7 days after a 3-day injection of dexamethasone (a total dose of 1.2 mg/rat intraperitoneally). At the first day after dexamethasone administration the moderate involution and atrophy of thymus histology were observed with simultaneous fall in cortical cellularity and mitotic activity of thymocytes. More rapid fall appeared in the inner cortex. The number of apoptotic (TUNEL-positive) cells was significantly increased. On the days 5 and 7 the expression of apoptosis and the cell proliferation were at almost normal level. The findings suggest that dexamethasone-induced apoptosis of cortical thymic lymphocytes, mainly correlated with synchronous inhibition of mitosis and cell number fall in thymus. The main target sites of dexamethasone injury were cells in the inner cortex of lobuli thymi.

Wind tunnel test on PC cable-stayed bridge; PC shachokyo no taifu seino shiken

Energy Technology Data Exchange (ETDEWEB)

Kubo, Y. [Kyushu Inst. of Technology, Kitakyushu (Japan). Faculty of Engineering

1997-05-30

This paper describes the wind tunnel test on a PC cable-stayed bridge. The aerodynamic force that acts on a building is represented by the drag that works in the wind direction, the lift that works perpendicularly to the wind direction, and the aerodynamic moment that causes rotation. In the measurement of wind load, a girder is partially extracted in the wind tunnel and set in a three-component balance, and the drag, lift, and aerodynamic moment are measured using a strain meter while blowing the wind. In a wind tunnel experiment, the similarity on Reynolds number, field number, rigidity, hydraulic force, structural attenuation, and reduced wind velocity is required. However, the wind velocity in the actual bridge uses the same air as that in an experiment. The similarity rule on the Reynolds is not thus satisfied. It is necessary to cause no self-excited vibration (galloping and flutter) as wind-resistant performance and suppress the eddy excitation to less than the allowable amplitude. Moreover, the three-dimensional experiment using an elastic model is conducted in addition to the two-dimensional experiment using a rigid model. In the three-dimensional experiment, various vibration modes that occur in the actual bridge appear. 12 refs., 15 figs.

Study of the stall delay phenomenon and of wind turbine blade dynamics using numerical approaches and NREL's wind tunnel tests

Energy Technology Data Exchange (ETDEWEB)

Breton, Simon-Philippe

2008-06-15

The production of electricity from wind has experienced an enormous growth worldwide in the last 20 years. It is now widely seen as a serious alternative to more conventional energy production methods. Improvements are however still possible to make it more cost-effective. This can be done through a better understanding of the fundamental phenomena involved in the interaction of the wind with the wind turbine rotor. This growth in the production of energy from wind is expected to continue at a similar rate in the years to come, helped by the installation of wind turbines at sea, that is becoming a hot topic in the wind energy field today. The phenomenon of stall delay affecting rotating wind turbine blades is an example of an aerodynamic phenomenon that is not yet fully understood. Several models exist to correct for this effect. Five such models were first tested within a vortex wake simulation code based on the modelling of a prescribed wake behind the rotor of the turbine. Comparison was made with wind tunnel test data acquired in head-on flow on a two-bladed 10.1 diameter wind turbine at the National Renewable Energy Laboratories (NREL) in 2000. It revealed a general overprediction of the stall delay effects, at the same time as great disparity was obtained between the different models. Conclusions from this work served as a starting point for a much more thorough investigation on this subject, where several models were tested in terms of different quantities using the same simulation code, and where the application of some of the models was improved. Overprediction of the loads was once again obtained when comparison was made to the NREL results in head-on flow, and none of the models was found to correctly represent the flow physics involved. The premises on which each of the models relies were discussed as a means of better understanding and modelling this phenomenon. The important issue of tip loss was also covered, and guidelines were suggested to improve

Wind tunneling testing and analysis relating to the spinning of light aircraft

Science.gov (United States)

Mccormick, B. W.; Zilliac, G. G.; Ballin, M. G.

1984-01-01

Included is a summary of two studies related to the spinning of light aircraft. The first study was conducted to demonstrate that the aerodynamic forces and moments acting on a tail of a spinning aircraft can be obtained from static wind-tunnel tests. The second study analytically investigated spinning using a high angle-of-attack aerodynamic model derived from a static wind-tunnel data base. The validity of the aerodynamic model is shown by comparisons with rotary-balance data and forced-oscillation tests. The results of a six-degree-of-freedom analysis show that the dynamics and aerodynamics of the steep- and flat-spin modes of a modified Yankee have been properly modeled.

Large-area photogrammetry based testing of wind turbine blades

Science.gov (United States)

Poozesh, Peyman; Baqersad, Javad; Niezrecki, Christopher; Avitabile, Peter; Harvey, Eric; Yarala, Rahul

2017-03-01

An optically based sensing system that can measure the displacement and strain over essentially the entire area of a utility-scale blade leads to a measurement system that can significantly reduce the time and cost associated with traditional instrumentation. This paper evaluates the performance of conventional three dimensional digital image correlation (3D DIC) and three dimensional point tracking (3DPT) approaches over the surface of wind turbine blades and proposes a multi-camera measurement system using dynamic spatial data stitching. The potential advantages for the proposed approach include: (1) full-field measurement distributed over a very large area, (2) the elimination of time-consuming wiring and expensive sensors, and (3) the need for large-channel data acquisition systems. There are several challenges associated with extending the capability of a standard 3D DIC system to measure entire surface of utility scale blades to extract distributed strain, deflection, and modal parameters. This paper only tries to address some of the difficulties including: (1) assessing the accuracy of the 3D DIC system to measure full-field distributed strain and displacement over the large area, (2) understanding the geometrical constraints associated with a wind turbine testing facility (e.g. lighting, working distance, and speckle pattern size), (3) evaluating the performance of the dynamic stitching method to combine two different fields of view by extracting modal parameters from aligned point clouds, and (4) determining the feasibility of employing an output-only system identification to estimate modal parameters of a utility scale wind turbine blade from optically measured data. Within the current work, the results of an optical measurement (one stereo-vision system) performed on a large area over a 50-m utility-scale blade subjected to quasi-static and cyclic loading are presented. The blade certification and testing is typically performed using International

Relevant Criteria for Testing the Quality of Models for Turbulent Wind Speed Fluctuations

DEFF Research Database (Denmark)

Frandsen, Sten Tronæs; Ejsing Jørgensen, Hans; Sørensen, John Dalsgaard

2008-01-01

Seeking relevant criteria for testing the quality of turbulence models, the scale of turbulence and the gust factor have been estimated from data and compared with predictions from first-order models of these two quantities. It is found that the mean of the measured length scales is approximately...... 10% smaller than the IEC model for wind turbine hub height levels. The mean is only marginally dependent on trends in time series. It is also found that the coefficient of variation of the measured length scales is about 50%. 3  s and 10  s preaveraging of wind speed data are relevant for megawatt......-size wind turbines when seeking wind characteristics that correspond to one blade and the entire rotor, respectively. For heights exceeding 50-60  m, the gust factor increases with wind speed. For heights larger than 60-80  m, present assumptions on the value of the gust factor are significantly...

Background Pressure Profiles for Sonic Boom Vehicle Testing in the NASA Glenn 8- by 6-Foot Supersonic Wind Tunnel

Science.gov (United States)

Castner, Raymond; Shaw, Stephen; Adamson, Eric; Simerly, Stephanie

2013-01-01

In an effort to identify test facilities that offer sonic boom measurement capabilities, an exploratory test program was initiated using wind tunnels at NASA research centers. The subject of this report is the sonic boom pressure rail data collected in the Glenn Research Center 8- by 6-Foot Supersonic Wind Tunnel. The purpose is to summarize the lessons learned based on the test activity, specifically relating to collecting sonic boom data which has a large amount of spatial pressure variation. The wind tunnel background pressure profiles are presented as well as data which demonstrated how both wind tunnel Mach number and model support-strut position affected the wind tunnel background pressure profile. Techniques were developed to mitigate these effects and are presented.

Finite element analysis and modal testing of a rotating wind turbine

Science.gov (United States)

Carne, T. G.; Lobitz, D. W.; Nord, A. R.; Watson, R. A.

A finite element procedure, which includes geometric stiffening, and centrifugal and Coriolis terms resulting from the use of a rotating coordinate system, has been developed to compute the mode shapes and frequencies of rotating structures. Special application of this capability has been made to Darrieus, vertical axis wind turbines. In a parallel development effort, a technique for the modal testing of a rotating vertical axis wind turbine has been established to measure modal parameters directly. Results from the predictive and experimental techniques for the modal frequencies and mode shapes are compared over a wide range of rotational speeds.

Wind Tunnel Testing of Active Control System for Bridges

DEFF Research Database (Denmark)

Hansen, Henriette I.; Thoft-Christensen, Palle

This paper describes preparation of wind tunnel testing of the principle of using flaps to control the motion of suspension bridges. The experiment will take place at the Instituto Superior Technico Lisbon, Portugal. The bridge section model is constructed of foam with an aluminium frame. The flaps...... are regulated by servo motors. Neural networks are used to position the flaps in the optimal positions....

The application of cryogenics to high Reynolds number testing in wind tunnels. I - Evolution, theory, and advantages

Science.gov (United States)

Kilgore, R. A.; Dress, D. A.

1984-01-01

During the time which has passed since the construction of the first wind tunnel in 1870, wind tunnels have been developed to a high degree of sophistication. However, their development has consistently failed to keep pace with the demands placed on them. One of the more serious problems to be found with existing transonic wind tunnels is their inability to test subscale aircraft models at Reynolds numbers sufficiently near full-scale values to ensure the validity of using the wind tunnel data to predict flight characteristics. The Reynolds number capability of a wind tunnel may be increased by a number of different approaches. However, the best solution in terms of model, balance, and model support loads, as well as in terms of capital and operating cost appears to be related to the reduction of the temperature of the test gas to cryogenic temperatures. The present paper has the objective to review the evolution of the cryogenic wind tunnel concept and to describe its more important advantages.

Acoustic Noise Test Report for the U.S. Department of Energy 1.5-Megawatt Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Roadman, Jason [National Renewable Energy Lab. (NREL), Golden, CO (United States); Huskey, Arlinda [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-07-01

A series of tests were conducted to characterize the baseline properties and performance of the U.S. Department of Energy (DOE) 1.5-megawatt wind turbine (DOE 1.5) to enable research model development and quantify the effects of future turbine research modifications. The DOE 1.5 is built on the platform of GE's 1.5-MW SLE commercial wind turbine model. It was installed in a nonstandard configuration at the NWTC with the objective of supporting DOE Wind Program research initiatives such as A2e. Therefore, the test results may not represent the performance capabilities of other GE 1.5-MW SLE turbines. The acoustic noise test documented in this report is one of a series of tests carried out to establish a performance baseline for the DOE 1.5 in the NWTC inflow environment.

Monitoring of Wind Turbine Gearbox Condition through Oil and Wear Debris Analysis: A Full-Scale Testing Perspective

Energy Technology Data Exchange (ETDEWEB)

Sheng, Shuangwen

2016-10-01

Despite the wind industry's dramatic development during the past decade, it is still challenged by premature turbine subsystem/component failures, especially for turbines rated above 1 MW. Because a crane is needed for each replacement, gearboxes have been a focal point for improvement in reliability and availability. Condition monitoring (CM) is a technique that can help improve these factors, leading to reduced turbine operation and maintenance costs and, subsequently, lower cost of energy for wind power. Although technical benefits of CM for the wind industry are normally recognized, there is a lack of published information on the advantages and limitations of each CM technique confirmed by objective data from full-scale tests. This article presents first-hand oil and wear debris analysis results obtained through tests that were based on full-scale wind turbine gearboxes rated at 750 kW. The tests were conducted at the 2.5-MW dynamometer test facility at the National Wind Technology Center at the National Renewable Energy Laboratory. The gearboxes were tested in three conditions: run-in, healthy, and damaged. The investigated CM techniques include real-time oil condition and wear debris monitoring, both inline and online sensors, and offline oil sample and wear debris analysis, both onsite and offsite laboratories. The reported results and observations help increase wind industry awareness of the benefits and limitations of oil and debris analysis technologies and highlight the challenges in these technologies and other tribological fields for the Society of Tribologists and Lubrication Engineers and other organizations to help address, leading to extended gearbox service life.

Wind power development field test project at Ashibe-cho. Detailed wind characteristics survey; Ashibecho ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A detailed wind characteristics survey was conducted at Ashibe-cho, Iki-gun, Nagasaki Prefecture, on the assumption that a wind power generation system would be constructed. The survey was a 1-year project from October 1998 through September 1999, and wind characteristics such as the average wind speed, average wind direction, standard deviation of wind velocity, and the maximum instantaneous wind speed were observed. The observation point was fixed at 20m above ground, the minimum time unit for observation was 10 minutes, and the 10-minute average value was defined as the measured value. For the maximum instantaneous wind speed, the minimum time unit for observation was set to be 2 seconds. The yearly average wind speed was 5.8m/s and the maximum wind speed in the period was 35m/s. Winds came from the prevailing direction of NE (21.3%), and then from NNE (14.7%) and ENE (7.9%). The wind axis was in the NE-SW direction, and the total wind direction occurrence rate from the 6 directions was 60.2%. Turbulence intensity was 0.19 at wind speed 2.0m/s or more and 0.17 at wind speed 4.0m/s or more. Estimated wind turbine yearly operating factors of 66-84% were obtained using rated values of a 150kW, 300kW, and 750kW-class wind turbines. (NEDO)

Simulation of Small Wind Turbine Generation System Using Ring Winding Slotless PMSG by FEM

OpenAIRE

徳永, 翔平; 袈裟丸, 勝己; Tokunaga, Shohei; Kesamaru, Katsumi

2011-01-01

This paper describes a novel small wind turbine generation system with ring winding slotless PMSG. To reduce cogging torque, ring winding PM generator is used for a wind turbine generator. Using finite element analysis, the characteristics of slotless PMSGs are elucidated and the dynamic performance of the proposed system with MPPT control is represented. In this paper, the constant wind test and the quasi-natural wind test are conducted. The results of these tests indicate the proposed syste...

Experiences in simulating and testing coordinated voltage control provided by multiple wind power plants

Energy Technology Data Exchange (ETDEWEB)

Arlaban, T.; Alonso, O.; Ortiz, D. [Acciona Windpower S.A. (Spain); Peiro, J.; Rivas, R. [Red Electrica de Espana SAU (Spain); Quinonez-Varela, G.; Lorenzo, P. [Acciona Energia S.A. (Spain)

2011-07-01

This document presents some field tests performed in a transmission system node in order to check the adequacy of voltage control performance by multiple wind power plants, with an overall capacity of 395 MW. It briefly explains the Spanish TSO motivation towards new voltage control requirements and the necessity of performing such tests in order to set the most convenient voltage control parameters and to verify the stable operation. It presents how different the voltage control capability between modern wind turbines (DFIG) and older ones (SCIG) specifically retrofitted for voltage control is. (orig.)

Characterizing the Influence of Abstraction in Full-Scale Wind Turbine Nacelle Testing: Preprint

Energy Technology Data Exchange (ETDEWEB)

Schkoda, Ryan; Bibo, Amin; Guo, Yi; Lambert, Scott; Wallen, Robb

2016-08-01

In recent years, there has been a growing interest in full-scale wind turbine nacelle testing to complement individual component testing. As a result, several wind turbine nacelle test benches have been built to perform such testing with the intent of loading the integrated components as they are in the field. However, when mounted on a test bench the nacelle is not on the top of a tower and does not have blades attached to it--this is a form of abstraction. This paper aims to quantify the influence of such an abstraction on the dynamic response of the nacelle through a series of simulation case studies. The responses of several nacelle components are studied including the main bearing, main shaft, gearbox supports, generator, and yaw bearing interface. Results are presented to highlight the differences in the dynamic response of the nacelle caused by the abstraction. Additionally, the authors provide recommendations for mitigating the effects of the abstraction.

Controllable Grid Interface for Testing Ancillary Service Controls and Fault Performance of Utility-Scale Wind Power Generation: Preprint

Energy Technology Data Exchange (ETDEWEB)

Gevorgian, Vahan; Koralewicz, Przemyslaw; Wallen, Robb; Muljadi, Eduard

2017-02-01

The rapid expansion of wind power has led many transmission system operators to demand modern wind power plants to comply with strict interconnection requirements. Such requirements involve various aspects of wind power plant operation, including fault ride-through and power quality performance as well as the provision of ancillary services to enhance grid reliability. During recent years, the National Renewable Energy Laboratory (NREL) of the U.S. Department of Energy has developed a new, groundbreaking testing apparatus and methodology to test and demonstrate many existing and future advanced controls for wind generation (and other renewable generation technologies) on the multimegawatt scale and medium-voltage levels. This paper describes the capabilities and control features of NREL's 7-MVA power electronic grid simulator (also called a controllable grid interface, or CGI) that enables testing many active and reactive power control features of modern wind turbine generators -- including inertial response, primary and secondary frequency responses, and voltage regulation -- under a controlled, medium-voltage grid environment. In particular, this paper focuses on the specifics of testing the balanced and unbalanced fault ride-through characteristics of wind turbine generators under simulated strong and weak medium-voltage grid conditions. In addition, this paper provides insights on the power hardware-in-the-loop feature implemented in the CGI to emulate (in real time) the conditions that might exist in various types of electric power systems under normal operations and/or contingency scenarios. Using actual test examples and simulation results, this paper describes the value of CGI as an ultimate modeling validation tool for all types of 'grid-friendly' controls by wind generation.

Aerodynamic research of a racing car based on wind tunnel test and computational fluid dynamics

Directory of Open Access Journals (Sweden)

Wang Jianfeng

2018-01-01

Full Text Available Wind tunnel test and computational fluid dynamics (CFD simulation are two main methods for the study of automotive aerodynamics. CFD simulation software solves the results in calculation by using the basic theory of aerodynamic. Calculation will inevitably lead to bias, and the wind tunnel test can effectively simulate the real driving condition, which is the most effective aerodynamics research method. This paper researches the aerodynamic characteristics of the wing of a racing car. Aerodynamic model of a racing car is established. Wind tunnel test is carried out and compared with the simulation results of computational fluid dynamics. The deviation of the two methods is small, and the accuracy of computational fluid dynamics simulation is verified. By means of CFD software simulation, the coefficients of six aerodynamic forces are fitted and the aerodynamic equations are obtained. Finally, the aerodynamic forces and torques of the racing car travel in bend are calculated.

Multi-site testing and evaluation of remote sensing instruments for wind energy applications

DEFF Research Database (Denmark)

Sanz Rodrigo, J.; Borbon Guillen, F.; Gomez Arranz, P.

2013-01-01

A procedure for testing and evaluation of remote sensing instruments that makes use of two test sites in flat and complex terrain is presented. To illustrate the method, a system intercomparison experiment is presented involving one sodar and two lidars (pulsed and continuous-wave). The wind...

Cross-Wind Modal Properties of Offshore Wind Turbines Identified by Full Scale Testing

DEFF Research Database (Denmark)

Damgaard, Mads; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard

2013-01-01

-2011, the paper evaluates the first natural frequency and modal damping of the structures. In addition, fitting of theoretical energy spectra to measured response spectra of operating turbines is presented as an alternative method of determining the system damping. Analyses show distinctly time-dependent cross......Cross-wind vibrations due to wave loading misaligned with wind turbulence are often a design driver for offshore wind turbine foundations. The phenomenon is characterised by increasing fatigue loads compared to the fore-aft fatigue and a small amount of system damping since almost no aerodynamic...

Field test of a lidar wind profiler

NARCIS (Netherlands)

Kunz, G.J.

1996-01-01

Wind speeds and wind directions are measured remotely using an incoherent backscatter lidar system operating at a wavelength of 1.06 mm with a maximum repetition rate of 13 Hz. The principle of the measurements is based on following detectable atmospheric structures, which are transported by the

A testing procedure for wind turbine generators based on the power grid statistical model

DEFF Research Database (Denmark)

Farajzadehbibalan, Saber; Ramezani, Mohammad Hossein; Nielsen, Peter

2017-01-01

In this study, a comprehensive test procedure is developed to test wind turbine generators with a hardware-in-loop setup. The procedure employs the statistical model of the power grid considering the restrictions of the test facility and system dynamics. Given the model in the latent space...

Efficient preliminary floating offshore wind turbine design and testing methodologies and application to a concrete spar design.

Science.gov (United States)

Matha, Denis; Sandner, Frank; Molins, Climent; Campos, Alexis; Cheng, Po Wen

2015-02-28

The current key challenge in the floating offshore wind turbine industry and research is on designing economic floating systems that can compete with fixed-bottom offshore turbines in terms of levelized cost of energy. The preliminary platform design, as well as early experimental design assessments, are critical elements in the overall design process. In this contribution, a brief review of current floating offshore wind turbine platform pre-design and scaled testing methodologies is provided, with a focus on their ability to accommodate the coupled dynamic behaviour of floating offshore wind systems. The exemplary design and testing methodology for a monolithic concrete spar platform as performed within the European KIC AFOSP project is presented. Results from the experimental tests compared to numerical simulations are presented and analysed and show very good agreement for relevant basic dynamic platform properties. Extreme and fatigue loads and cost analysis of the AFOSP system confirm the viability of the presented design process. In summary, the exemplary application of the reduced design and testing methodology for AFOSP confirms that it represents a viable procedure during pre-design of floating offshore wind turbine platforms. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Effects of wind turbines on UHF television reception: field tests in Denmark, November 1991

International Nuclear Information System (INIS)

Wright, D.T.

1992-01-01

As a result of a planning application for a wind farm comprising 20 wind turbines at Tynewydd Farm, Gilfach Goch in Mid Glamorgan, it became necessary to produce a Report discussing any detrimental effects the proposal might have on UHF television reception. In order to make that Report as definitive as possible, it was decided to carry out field tests on the exact model of wind turbine to be used to Tynewydd. This required a field trip to Denmark, and the opportunity was taken to make measurements on two other models of turbine at the same time. This Report presents the analysis of the results for all three turbines. (Author)

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

Energy Technology Data Exchange (ETDEWEB)

Cotrell, J.

2002-06-01

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

Analysis and elimination method of the effects of cables on LVRT testing for offshore wind turbines

Science.gov (United States)

Jiang, Zimin; Liu, Xiaohao; Li, Changgang; Liu, Yutian

2018-02-01

The current state, characteristics and necessity of the low voltage ride through (LVRT) on-site testing for grid-connected offshore wind turbines are introduced firstly. Then the effects of submarine cables on the LVRT testing are analysed based on the equivalent circuit of the testing system. A scheme for eliminating the effects of cables on the proposed LVRT testing method is presented. The specified voltage dips are guaranteed to be in compliance with the testing standards by adjusting the ratio between the current limiting impedance and short circuit impedance according to the steady voltage relationship derived from the equivalent circuit. Finally, simulation results demonstrate that the voltage dips at the high voltage side of wind turbine transformer satisfy the requirements of testing standards.

Wind power development field test project at Hirashima, Sakito-cho. Detailed wind characteristics survey; Sakitocho Hirashima ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A detailed wind characteristics survey was conducted at Hirashima, Sakito-cho, Nishisonogi-gun, Nagasaki Prefecture, on the assumption that a wind power generation system would be constructed. The survey was a 1-year project from October 1998 through September 1999, and wind characteristics such as the average wind speed, average wind direction, standard deviation of wind velocity, and the maximum instantaneous wind speed were observed. The observation point was fixed at 20m above ground, the minimum time unit for observation was 10 minutes, and the 10-minute average value was defined as the measured value. For the maximum instantaneous wind speed, the minimum time unit for observation was set to be 2 seconds. The yearly average wind speed was 7.1m/s and the maximum wind speed in the period was 37m/s. Winds came prevalently from N (13.9%), and then from NNE (13.3%), NW (12.2%), and NE (10.7%). The total wind direction occurrence rate involving the 4 directions was 50.1%. Turbulence intensity was 0.14 at wind speed 2.0m/s or more and 0.12 at wind speed 4.0m/s or more. Estimated wind turbine yearly operating factors of 77-87% were obtained using rated values of a 150kW, 300kW, and 750kW-class wind turbines. (NEDO)

Wind tunnel tests of biodegradable fugitive dust suppressants being considered to reduce soil erosion by wind at radioactive waste construction sites

International Nuclear Information System (INIS)

Ligotke, M.W.; Dennis, G.W.; Bushaw, L.L.

1993-10-01

Wind tunnel tests were performed of three fugitive dust control agents derived from potato and sugar beet products. These materials are being considered for use as dust suppressants to reduce the potential for transport of radioactive materials by wind from radioactive waste construction and remediation sites. Soil and dust control agent type, solution concentrations, application quantities, aging (or drying) conditions, surface disturbance, and wind and saltating sand eolian erosive stresses were selected and controlled to simulate application and exposure of excavated soil surfaces in the field. A description of the tests, results, conclusions, and recommendations are presented in this report. The results of this study indicate that all three dust control agents can protect exposed soil surfaces from extreme eolian stresses. It is also clear that the interaction and performance of each agent with various soil types may differ dramatically. Thus, soils similar to that received from ML should be best protected by high concentration (∼2.5%) solutions of potato starch at low water application levels (∼1 to 2 L/m 2 ). Because the effectiveness of PS on this soil type is degraded after a moderate amount of simulated rainfall, other options or additives should be considered if surfaces are to be protected for long intervals or during periods of intermittent rainfall and hot, windy conditions. On the other hand, XDCA should be considered when excavating sandy soils. It should be noted, however, that because the Hanford soil test results are based on a small number of tests, it would be prudent to perform additional tests prior to selecting a fugitive dust control agent for use at the Hanford Site. While fermented potato waste was not the best fixative used on either soil, it did perform reasonably well on both soil types (better than XDCA on Idaho soil and better than PS on Hanford soil)

First electrical tests on a machine with an AC superconducting stator winding

International Nuclear Information System (INIS)

Brunet, Y.; Tixador, P.; Laumond, Y.; Sabrie, J.L.

1988-01-01

A three phase superconducting stator winding has been built using a low losses NbTi wire under 50 Hz varying magnetic field and current. It has first been necessary to design an horizontal helium cryostat with fiber-glass composites to avoid the permanent eddy-current losses of the rotating magnetic fields. The liquid helium vessel, containing the armature, is dismountable. The cryostat is 900 mm long and the rotor bore has a diameter of 180 mm. The windings are wounded on five concentric fiber glass cylinders with a thin impregnation of an epoxy film adhesive. The first electrical tests have been performed using a normal iron rotor inside the superconducting stator. No load and permanent tests have been achieved up to a power of 13 kVA. The 18,5 kVA predicted have not been reached because of the present inductor, not yet superconducting

Experimental hydraulic analysis in conduction tunnels at the trunk section working as a channel considering compound roughness; Analisis hidraulico experimental en tuneles de conduccion en seccion baul trabajando como canal, considerando rugosidades compuestas

Energy Technology Data Exchange (ETDEWEB)

Marengo-Mogollon, Humberto; Cortes-Cortes, Carlos [Comision Federal de Electricidad (Mexico); Arreguin-Cortes, Felipe I [Comision Nacional del Agua (Mexico)

2008-01-15

This paper presents the roughness coefficients of a conduction tunnel at the trunk section working as a channel obtained experimentally using a hydraulic model of the diversion tunnel of the Hydroelectric Project called El Cajon (Mexico). A comparative analysis between experimental and theoretical coefficients obtained in the literature is shown. [Spanish] Se presentan los coeficientes de rugosidad compuesta de un tunel de conduccion en seccion baul trabajando como canal obtenidos en forma experimental en un modelo hidraulico del tunel de desvio del Proyecto Hidroelectrico El Cajon (Mexico). Se muestra un analisis comparativo entre los coeficientes experimentales y los teoricos obtenidos en la literatura.

Utilisation of real-scale renewable energy test facility for validation of generic wind turbine and wind power plant controller models

DEFF Research Database (Denmark)

Zeni, Lorenzo; Gevorgian, Vahan; Wallen, Robb

2016-01-01

This article presents an example of application of a modern test facility conceived for experiments regarding the integration of renewable energy in the power system. The capabilities of the test facility are used to validate dynamic simulation models of wind power plants and their controllers....... The models are based on standard and generic blocks. The successful validation of events related to the control of active power (control phenomena in...

Vibration analysis of 1 MW gearbox for the Avedoere wind turbine. Test bed measurements

International Nuclear Information System (INIS)

Crone, A.

1995-03-01

The investigations had several purposes: Firstly, to determine and evaluate the structure-borne noise source strength of the gearbox, which is relevant for the final gear noise emission from the wind turbine. Secondly, to select the potentially least noisy gear set out of two, which have been made for the output gear stage. And Thirdly, to obtain the natural vibration modes of the gearbox structure, in order to determine if the structure-borne noise, transmitted to the wind turbine structure, will be amplified due to resonance conditions. Additional vibration tests were carried out. Among these, trials of 'in situ' measurement of the Transmission Error of the output gear stage, and measurements of the torsional vibrations of the input and output shaft. The test of the two output gear sets (from Flender AG and ELKRAFT A.m.b.A.) had the aim to determine the least noisy one of two different tooth profiles. Both gear sets were intended for the Avedoere Wind Turbine when it, in its first period of operation, is going to operate as a stall regulated turbine. After the first mesurements and the exchange of the Flender-designed gear set with the ELKRAFT-designed gear set, troubles with the backmost bearing of the intermediate shaft arose. The evaluation of the structure-borne noise source strength (expressed as the vibration velocity level), has in general been made at load conditions which correspond to the conditions in the wind turibne at a wind speed of 8 m/s, 10 m above terrain (v 10 ). This condition, is the one normally used when the noise emission from wind turbines is evaluated. At the comparison of the two gear sets against each other, the influence of the torque load on the source strength has also been considered. This comparison may indicate the load at which the profile correction is most effective, and may determine the noise potential of the gearbox at wind speeds lower than 8 m/s, which could also be of interest

Standard test method to determine the performance of tiled roofs to wind-driven rain

Directory of Open Access Journals (Sweden)

Sánchez de Rojas, M. I.

2008-09-01

Full Text Available The extent to which roof coverings can resist water penetration from the combination of wind and rain, commonly referred to as wind driven rain, is important for the design of roofs. A new project of European Standard prEN 15601 (1 specifies a method of test to determine the performance of the roof covering against wind driven rain. The combined action of wind and rain varies considerably with geographical location of a building and the associated differences in the rain and wind climate. Three windrain conditions and one deluge condition covering Northern Europe Coastal, Central Europe and Southern Europe are specified in the project standard, each subdivided into four wind-speeds and rainfall rates to be applied to the test. The project does not contain information on the level of acceptable performance.Para el diseño de los tejados es importante determinar el punto hasta el cual éstos pueden resistirse a la penetración de agua causada por la combinación de viento y lluvia. Un nuevo proyecto de Norma Europeo prEN 15601 (1 especifica un método de ensayo para determinar el comportamiento del tejado frente a la combinación de viento y lluvia. La acción combinada de viento y lluvia varía considerablemente con la situación geográfica de un edificio y las diferencias asociadas al clima de la lluvia y del viento. El proyecto de norma especifica las condiciones de viento y lluvia y una condición de diluvio para cada una de las tres zonas de Europa: Europa del Norte y Costera, Europa Central y Europa del Sur, cada una subdividida en cuatro condiciones de velocidades de viento y caudal de lluvia para ser aplicadas en los ensayos. El proyecto no contiene la información sobre condiciones aceptables.

Uncertainty Analysis of OC5-DeepCwind Floating Semisubmersible Offshore Wind Test Campaign: Preprint

Energy Technology Data Exchange (ETDEWEB)

Robertson, Amy N [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-07-26

This paper examines how to assess the uncertainty levels for test measurements of the Offshore Code Comparison, Continued, with Correlation (OC5)-DeepCwind floating offshore wind system, examined within the OC5 project. The goal of the OC5 project was to validate the accuracy of ultimate and fatigue load estimates from a numerical model of the floating semisubmersible using data measured during scaled tank testing of the system under wind and wave loading. The examination of uncertainty was done after the test, and it was found that the limited amount of data available did not allow for an acceptable uncertainty assessment. Therefore, this paper instead qualitatively examines the sources of uncertainty associated with this test to start a discussion of how to assess uncertainty for these types of experiments and to summarize what should be done during future testing to acquire the information needed for a proper uncertainty assessment. Foremost, future validation campaigns should initiate numerical modeling before testing to guide the test campaign, which should include a rigorous assessment of uncertainty, and perform validation during testing to ensure that the tests address all of the validation needs.

The design, simulation and testing of an urban vertical axis wind turbine with the omni-direction-guide-vane

International Nuclear Information System (INIS)

Chong, W.T.; Fazlizan, A.; Poh, S.C.; Pan, K.C.; Hew, W.P.; Hsiao, F.B.

2013-01-01

Graphical abstract: Solar energy, renewable energy, urban wind energy, environment, augmented wind turbine. Highlights: ► A system for on-site wind–solar hybrid power generation and rain water collection. ► The omni-direction-guide-vane (ODGV) overcomes the weak wind and turbulence conditions in urban areas. ► The ODGV improves the wind turbine performance by speeding-up and guiding the wind. ► The ODGV is designed to blend into the building architecture with safety enhancement. ► The wind tunnel test and CFD simulation results are presented. - Abstract: A novel omni-direction-guide-vane (ODGV) that surrounds a vertical axis wind turbine (VAWT) is designed to improve the wind turbine performance. Wind tunnel testing was performed to evaluate the performance of a 5-bladed (Wortmann FX63-137 airfoil) H-rotor wind turbine, with and without the integration of the ODGV. The test was conducted using a scaled model turbine which was constructed to simulate the VAWT enclosed by the ODGV placed on a building. The VAWT shows an improvement on its self-starting behavior where the cut-in speed was reduced with the integration of the ODGV. Since the VAWT is able to self-start at a lower wind speed, the working hour of the wind turbine would increase. At a wind speed of 6 m/s and under free-running condition (only rotor inertia and bearing friction were applied), the ODGV helps to increase the rotor rotational speed by 182%. With extra load application at the same wind speed (6 m/s), the wind turbine power output was increased by 3.48 times at its peak torque with the aid of the ODGV. The working concept of the ODGV is to minimize the negative torque zone of a lift-type VAWT and to reduce turbulence and rotational speed fluctuation. It was verified by re-simulating the torque coefficient data of a single bladed (NACA 0015 airfoil) VAWT published by the Sandia National Laboratories. From the simulation results, with the presence of the ODGV, it was shown that the

Wind power development field test project at Okkobe-cho. Close survey on wind conditions; Okkobecho ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A survey was made on regional wind conditions on the assumption that a wind power generator was installed around Okkobe Rakuno-no-oka, Okkobe-cho, Monbetsu-gun, Hokkaido. The survey period was one year from Oct., 1998 to Sept., 1999. The observations were carried out on the average wind velocity, average wind direction, standard deviation of velocity, and the maximum instantaneous wind velocity. With a fixed point observation at 20 m above ground, and with the minimum observation time unit of 10 minutes, an average value during the 10 minutes was determined as the measurement of each category. However, the maximum instantaneous wind velocity was determined on the measurement with the minimum observation time unit of 2 seconds. The average wind velocity was 4.8 m/s, the maximum wind velocity during the period was 29.9 m/s, the prevailing wind direction was WSW (17.1%), the wind axis was WSW-ENE, and the total occurrence rate of wind direction was 51.1%. The intensity of turbulence was 0.19 at a wind velocity of 2.0 m/s or above and was 0.16 at 4.0 m/s or above. An estimated annual operation rate of a windmill was 59-77% using the rated value of a 150 kW, 300 kW and 750 kW class windmills. (NEDO)

Effects of wind turbines on UHF television reception: field tests in Denmark

International Nuclear Information System (INIS)

Sorenson, B.

1992-01-01

As a result of a planning application for a windfarm comprising 20 wind turbines at Tynewydd Farm, Gilfach Goch in Mid Glamorgan, a report discussing any detrimental effects the proposal might have on u.h.f. television reception was produced. In order to make the report as definitive as possible, it was decided to carry out field tests on the exact model of wind turbine to be used at Tynewydd. This required a field trip to Denmark, and the opportunity was taken to make measurements on two other models of turbine at the same time. This report presents the analysis of the results for all three turbines. (author)

Nacelle Chine Installation Based on Wind-Tunnel Test Using Efficient Global Optimization

Science.gov (United States)

Kanazaki, Masahiro; Yokokawa, Yuzuru; Murayama, Mitsuhiro; Ito, Takeshi; Jeong, Shinkyu; Yamamoto, Kazuomi

Design exploration of a nacelle chine installation was carried out. The nacelle chine improves stall performance when deploying multi-element high-lift devices. This study proposes an efficient design process using a Kriging surrogate model to determine the nacelle chine installation point in wind-tunnel tests. The design exploration was conducted in a wind-tunnel using the JAXA high-lift aircraft model at the JAXA Large-scale Low-speed Wind Tunnel. The objective was to maximize the maximum lift. The chine installation points were designed on the engine nacelle in the axial and chord-wise direction, while the geometry of the chine was fixed. In the design process, efficient global optimization (EGO) which includes Kriging model and genetic algorithm (GA) was employed. This method makes it possible both to improve the accuracy of the response surface and to explore the global optimum efficiently. Detailed observations of flowfields using the Particle Image Velocimetry method confirmed the chine effect and design results.

Wind energy expo '82 and national conference American Wind Energy Association

Energy Technology Data Exchange (ETDEWEB)

Nelson, V. (ed.)

1982-01-01

Separate abstracts were prepared for 41 papers in this conference report. Wind farms, large wind turbines, new wind turbines, marketing small wind systems, programs, performance, and economics, analytic methods, testing, power conversion, and rotor systems are the principal topics covered.

Wind power development field test project at Maruyama-machi. Close survey on wind conditions; Maruyamamachi ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A survey was made on wind conditions in Maruyama-machi, Awa-gun, Chiba prefecture, on the assumption that a wind power generation system was installed therein. The survey period was one year from Oct., 1998 to Sept., 1999. The observations were carried out on the average wind velocity, average wind direction, standard deviation of velocity, and the maximum instantaneous wind velocity. With a fixed point observation at 20 m above ground, and with the minimum observation time unit of 10 minutes, an average value during the 10 minutes was determined as the measurement of each category. However, the maximum instantaneous wind velocity was determined on the measurement with the minimum observation time unit of 2 seconds. The average annual wind velocity was 3.5 m/s, the maximum wind velocity during the period was 27 m/s, and the wind axis was WSW-ENE, with the total occurrence rate of the wind direction 44.1%. The intensity of turbulence was 0.23 at a wind velocity of 2.0 m/s or above and was 0.22 at 4.0 m/s or above. An estimated annual operation rate of a windmill was 40-60% using the rated value of a 150 kW, 300 kW and 750 kW class windmills. (NEDO)

A Novel Wind Speed Forecasting Model for Wind Farms of Northwest China

Science.gov (United States)

Wang, Jian-Zhou; Wang, Yun

2017-01-01

Wind resources are becoming increasingly significant due to their clean and renewable characteristics, and the integration of wind power into existing electricity systems is imminent. To maintain a stable power supply system that takes into account the stochastic nature of wind speed, accurate wind speed forecasting is pivotal. However, no single model can be applied to all cases. Recent studies show that wind speed forecasting errors are approximately 25% to 40% in Chinese wind farms. Presently, hybrid wind speed forecasting models are widely used and have been verified to perform better than conventional single forecasting models, not only in short-term wind speed forecasting but also in long-term forecasting. In this paper, a hybrid forecasting model is developed, the Similar Coefficient Sum (SCS) and Hermite Interpolation are exploited to process the original wind speed data, and the SVM model whose parameters are tuned by an artificial intelligence model is built to make forecast. The results of case studies show that the MAPE value of the hybrid model varies from 22.96% to 28.87 %, and the MAE value varies from 0.47 m/s to 1.30 m/s. Generally, Sign test, Wilcoxon's Signed-Rank test, and Morgan-Granger-Newbold test tell us that the proposed model is different from the compared models.

Expert group study on recommended practices for wind turbine testing and evaluation

Energy Technology Data Exchange (ETDEWEB)

Ljunggren, S; Gustafsson, A; Trenka, A R

1984-01-01

The major goal of this documents is to facilitate comparisons of noise measurements made in different countries by different investigators. The secondary goal is to provide an engineering data base for the development and validation of analytical acoustic prediction techniques. The evaluation of wind turbines must encompass all aspects of a Wind Energy Conversion System (WECS) ranging from: energy production, quality of power, reliability, durability and safety, through to cost effectiveness or economics, noise characteristics, impact on the environment and electromagnetic interference. The development of internationally agreements on evaluation procedures for each of these areas is needed now to aid in the development of the industry, while strengthening confidence and preventing chaos in the market. It is the purpose of the proposed recommendatons for wind turbine testing to address the development of internationally agreed upon test procedures which deal with each of the above noted aspects for characteizing WECS. The IEA expert committee will pursue this procedures in each of the following areas, power performance, cost of energy from WECS, fatigue evaluation, acountics, electromagnetic interference, safety and reliability and quality of power. This paper addresses the forth item - Acoustics. The expert committee will seek to gain approval of the procedures in each member country through the IEA agreements. The recommendations shall be regularly reviewed and areas in need of further investigation shall be identified. (AB).

Wind and Wake Sensing with UAV Formation Flight: System Development and Flight Testing

Science.gov (United States)

Larrabee, Trenton Jameson

sensing data using UAVs in formation flight. This has been achieved and well documented before in manned aircraft but very little work has been done on UAV wake sensing especially during flight testing. This document describes the development and flight testing of small unmanned aerial system (UAS) for wind and wake sensing purpose including a Ground Control Station (GCS) and UAVs. This research can be stated in four major components. Firstly, formation flight was obtained by integrating a formation flight controller on the WVU Phastball Research UAV aircraft platform from the Flight Control Systems Laboratory (FCSL) at West Virginia University (WVU). Second, a new approach to wind estimation using an Unscented Kalman filter (UKF) is discussed along with results from flight data. Third, wake modeling within a simulator and wake sensing during formation flight is shown. Finally, experimental results are used to discuss the "sweet spot" for energy harvesting in formation flight, a novel approach to cooperative wind estimation, and gust suppression control for a follower aircraft in formation flight.

Development of a wind energy converter and investigation of its operational function. Part 4: Test setup and results of measurement

Science.gov (United States)

Armbrust, S.; Molly, J. P.

1982-12-01

Measurements made during test operations at the MODA.10 plant as well as at a 25 years old 6 kW wind energy converter are presented. The test arrangements, measurement results of both wind energy converters, and the experience gained are described.

Solar wind stream evolution at large heliocentric distances - Experimental demonstration and the test of a model

Science.gov (United States)

Gosling, J. T.; Hundhausen, A. J.; Bame, S. J.

1976-01-01

A stream propagation model which neglects all dissipation effects except those occurring at shock interfaces, was used to compare Pioneer-10 solar wind speed observations, during the time when Pioneer 10, the earth, and the sun were coaligned, with near-earth Imp-7 observations of the solar wind structure, and with the theoretical predictions of the solar wind structure at Pioneer 10 derived from the Imp-7 measurements, using the model. The comparison provides a graphic illustration of the phenomenon of stream steepening in the solar wind with the attendant formation of forward-reverse shock pairs and the gradual decay of stream amplitudes with increasing heliocentric distance. The comparison also provides a qualitative test of the stream propagation model.

Experimental and numerical study of a 10MW TLP wind turbine in waves and wind

DEFF Research Database (Denmark)

Pegalajar Jurado, Antonio Manuel; Hansen, Anders Mandrup; Laugesen, Robert

2016-01-01

with the tests by matching key system features, namely the steady thrust curve and the decay tests in water. The calibrated model is used to reproduce the wind-wave climates in the laboratory, including regular and irregular waves, with and without wind. The model predictions are compared to the measured data......This paper presents tests on a 1:60 version of the DTU 10MW wind turbine mounted on a tension leg platform and their numerical reproduction. Both the experimental setup and the numerical model are Froude-scaled, and the dynamic response of the floating wind turbine to wind and waves is compared......, and a good agreement is found for surge and heave, while some discrepancies are observed for pitch, nacelle acceleration and line tension. The addition of wind generally improves the agreement with test results. The aerodynamic damping is identified in both tests and simulations. Finally, the sources...

Morphing wing system integration with wind tunnel testing =

Science.gov (United States)

Guezguez, Mohamed Sadok

Preserving the environment is a major challenge for today's aviation industry. Within this context, the CRIAQ MDO 505 project started, where a multidisciplinary approach was used to improve aircraft fuel efficiency. This international project took place between several Canadian and Italian teams. Industrial teams are Bombardier Aerospace, Thales Canada and Alenia Aermacchi. The academic partners are from Ecole de Technologie Superieure, Ecole Polytechnique de Montreal and Naples University. Teams from 'CIRA' and IAR-NRC research institutes had, also, contributed on this project. The main objective of this project is to improve the aerodynamic performance of a morphing wing prototype by reducing the drag. This drag reduction is achieved by delaying the flow transition (from laminar to turbulent) by performing shape optimization of the flexible upper skin according to different flight conditions. Four linear axes, each one actuated by a 'BLDC' motor, are used to morph the skin. The skin displacements are calculated by 'CFD' numerical simulation based on flow parameters which are Mach number, the angle of attack and aileron's angle of deflection. The wing is also equipped with 32 pressure sensors to experimentally detect the transition during aerodynamic testing in the subsonic wind tunnel at the IAR-NRC in Ottawa. The first part of the work is dedicated to establishing the necessary fieldbus communications between the control system and the wing. The 'CANopen' protocol is implemented to ensure real time communication between the 'BLDC' drives and the real-time controller. The MODBUS TCP protocol is used to control the aileron drive. The second part consists of implementing the skin control position loop based on the LVDTs feedback, as well as developing an automated calibration procedure for skin displacement values. Two 'sets' of wind tunnel tests were carried out to, experimentally, investigate the morphing wing controller effect; these tests also offered the

Suppression of background noise in a transonic wind-tunnel test section

Science.gov (United States)

Schutzenhofer, L. A.; Howard, P. W.

1975-01-01

Some exploratory tests were recently performed in the transonic test section of the NASA Marshall Space Flight Center 14-in. wind tunnel to suppress the background noise. In these tests, the perforated walls of the test section were covered with fine wire screens. The screens eliminated the edge tones generated by the holes in the perforated walls and significantly reduced the tunnel background noise. The tunnel noise levels were reduced to such a degree by this simple modification at Mach numbers 0.75, 0.9, 1.1, 1.2, and 1.46 that the fluctuating pressure levels of a turbulent boundary layer could be measured on a 5-deg half-angle cone.

Experiences with a high-blockage model tested in the NASA Ames 12-foot pressure wind tunnel

Science.gov (United States)

Coder, D. W.

1984-01-01

Representation of the flow around full-scale ships was sought in the subsonic wind tunnels in order to a Hain Reynolds numbers as high as possible. As part of the quest to attain the largest possible Reynolds number, large models with high blockage are used which result in significant wall interference effects. Some experiences with such a high blockage model tested in the NASA Ames 12-foot pressure wind tunnel are summarized. The main results of the experiment relating to wind tunnel wall interference effects are also presented.

Framework for Testing the Effectiveness of Bat and Eagle Impact-Reduction Strategies at Wind Energy Projects

Energy Technology Data Exchange (ETDEWEB)

Sinclair, Karin [National Renewable Energy Lab. (NREL), Golden, CO (United States); DeGeorge, Elise [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-04-13

The objectives of this framework are to facilitate the study design and execution to test the effectiveness of bat and eagle impact-reduction strategies at wind energy sites. Through scientific field research, the wind industry and its partners can help determine if certain strategies are ready for operational deployment or require further development. This framework should be considered a living document to be improved upon as fatality-reduction technologies advance from the initial concepts to proven readiness (through project- and technology-specific testing) and as scientific field methods improve.

Structural fatigue test results for large wind turbine blade sections

Science.gov (United States)

Faddoul, J. R.; Sullivan, T. L.

1982-01-01

In order to provide quantitative information on the operating life capabilities of wind turbine rotor blade concepts for root-end load transfer, a series of cantilever beam fatigue tests was conducted. Fatigue tests were conducted on a laminated wood blade with bonded steel studs, a low cost steel spar (utility pole) with a welded flange, a utility pole with additional root-end thickness provided by a swaged collar, fiberglass spars with both bonded and nonbonded fittings, and, finally, an aluminum blade with a bolted steel fitting (Lockheed Mod-0 blade). Photographs, data, and conclusions for each of these tests are presented. In addition, the aluminum blade test results are compared to field failure information; these results provide evidence that the cantilever beam type of fatigue test is a satisfactory method for obtaining qualitative data on blade life expectancy and for identifying structurally underdesigned areas (hot spots).

Report on the field test project for wind power development at Kamiyaku Town (wind characteristics investigation); Kamiyakucho ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-11-01

Wind characteristics are observed for a year at the above town located at the northern end of the Yakushima island, Kagoshima Prefecture. The exponential index of the wind speed distribution in the vertical direction is 6.06 with all the directions averaged, and is so high as 8.4/13.6 in the wind directions (W/E). Prudence should be exercised, when to estimate the wind speed at the wind turbine hub altitude, against disjunction from the simple exponential law due to geographical peculiarities of the observation location. Turbulence intensity is low and is 0.15 when the wind speed is 2m/s or more, not exerting an ill effect on wind power development. As for the total wind direction occurrence rate on the prevalent wind axis, 78.2% is recorded, which is much higher than the reference value (60%). The average wind speed on this wind axis is high, and this shows that the location is quite suitable for wind power development. The annual average wind speed of 6.3m/s is much higher than the reference value, this again promising a success. The wind energy density of 478W/m{sup 2} is sufficiently high, as compared with the reference value (215W/m{sup 2}). Since there are possibilities of a maximum instantaneous wind speed of over 60m/s, caution is to be used in determining wind endurance for the wind turbine design. The annual capacity ratios for the 150/300/750kW wind turbine models are 33.8/36.5/36.9%, respectively, higher than the NEDO-provided reference value (17% or higher) and predicting sufficient power generation. (NEDO)

Wind Tunnel Modeling Of Wind Flow Over Complex Terrain

Science.gov (United States)

Banks, D.; Cochran, B.

2010-12-01

This presentation will describe the finding of an atmospheric boundary layer (ABL) wind tunnel study conducted as part of the Bolund Experiment. This experiment was sponsored by Risø DTU (National Laboratory for Sustainable Energy, Technical University of Denmark) during the fall of 2009 to enable a blind comparison of various air flow models in an attempt to validate their performance in predicting airflow over complex terrain. Bohlund hill sits 12 m above the water level at the end of a narrow isthmus. The island features a steep escarpment on one side, over which the airflow can be expected to separate. The island was equipped with several anemometer towers, and the approach flow over the water was well characterized. This study was one of only two only physical model studies included in the blind model comparison, the other being a water plume study. The remainder were computational fluid dynamics (CFD) simulations, including both RANS and LES. Physical modeling of air flow over topographical features has been used since the middle of the 20th century, and the methods required are well understood and well documented. Several books have been written describing how to properly perform ABL wind tunnel studies, including ASCE manual of engineering practice 67. Boundary layer wind tunnel tests are the only modelling method deemed acceptable in ASCE 7-10, the most recent edition of the American Society of Civil Engineers standard that provides wind loads for buildings and other structures for buildings codes across the US. Since the 1970’s, most tall structures undergo testing in a boundary layer wind tunnel to accurately determine the wind induced loading. When compared to CFD, the US EPA considers a properly executed wind tunnel study to be equivalent to a CFD model with infinitesimal grid resolution and near infinite memory. One key reason for this widespread acceptance is that properly executed ABL wind tunnel studies will accurately simulate flow separation

Wind tunnel test on airfoil Riso-B1-18 with an Active Trailing Edge Flap

DEFF Research Database (Denmark)

Bak, Christian; Gaunaa, Mac; Andersen, Peter Bjørn

2010-01-01

A wind tunnel test of the wind turbine airfoil Risø-B1-18 equipped with an Active Trailing Edge Flap (ATEF) was carried out. The ATEF was 9% of the total chord, made of piezo electric actuators attached to the trailing edge of a non-deformable airfoil and actuated using an (electric) amplifier....... The airfoil was tested at Re = 1.66 × 106. Steady state and dynamic tests were carried out with prescribed deflections of the ATEF. The steady state tests showed that deflecting the ATEF towards the pressure side (positive ) translated the lift curve to higher lift values and deflecting the ATEF towards...... the suction side (negative ) translated the lift curve to lower lift values. Testing the airfoil for a step change of the ATEF from = -3.0 to +1.8 showed that the obtainable cl was 0.10 to 0.13 in the linear part of the lift curve. Modeling the step response with an indicial function formulation showed...

Fundamentals for remote structural health monitoring of wind turbine blades - a preproject. Annex E. Full-scale test of wind turbine blade, using sensors and NDT

DEFF Research Database (Denmark)

Kristensen, O.J.D.; McGugan, Malcolm; Sendrup, P.

2002-01-01

A 19.1 metre wind turbine blade was subjected to static tests. The purpose of the test series was to verify the abilities of different types of sensors to detect damage in wind turbine blades. Prior to each of the static test-series an artificial damagewas made on the blade. The damage made...... for each test-series was surveyed during each series by acoustic emission, fiber optic micro bend displacement transducers and strain gauges. The propagation of the damage was determined by use of ultra sonic andX-ray surveillance during stops in the test-series. By use of acoustic emission it was possible...... to measure damage propagation before the propagation was of visible size. By use of fiber optic micro bend displacement transducers and strain gauges it waspossible to measure minor damage propagation. By use of both ultra sonic, and X-ray NDT-equipment it were possible to determine the size of propagated...

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

Energy Technology Data Exchange (ETDEWEB)

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

1995-10-01

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

Performance tests of a power-electronics converter for multi-megawatt wind turbines using a grid emulator

International Nuclear Information System (INIS)

Averous, Nurhan Rizqy; Berthold, Anica; Monti, Antonello; De Doncker, Rik W.; Schneider, Alexander; Schwimmbeck, Franz

2016-01-01

A vast increase of wind turbines (WT) contribution in the modern electrical grids have led to the development of grid connection requirements. In contrast to the conventional test method, testing power-electronics converters for WT using a grid emulator at Center for Wind Power Drives (CWD) RWTH Aachen University offers more flexibility for conducting test scenarios. Further analysis on the performance of the device under test (DUT) is however required when testing with grid emulator since the characteristic of the grid emulator might influence the performance of the DUT. This paper focuses on the performance analysis of the DUT when tested using grid emulator. Beside the issue regarding the current harmonics, the performance during Fault Ride-Through (FRT) is discussed in detail. A power hardware in the loop setup is an attractive solution to conduct a comprehensive study on the interaction between the power-electronics converters and the electrical grids. (paper)

Performance tests of a power-electronics converter for multi-megawatt wind turbines using a grid emulator

Science.gov (United States)

Rizqy Averous, Nurhan; Berthold, Anica; Schneider, Alexander; Schwimmbeck, Franz; Monti, Antonello; De Doncker, Rik W.

2016-09-01

A vast increase of wind turbines (WT) contribution in the modern electrical grids have led to the development of grid connection requirements. In contrast to the conventional test method, testing power-electronics converters for WT using a grid emulator at Center for Wind Power Drives (CWD) RWTH Aachen University offers more flexibility for conducting test scenarios. Further analysis on the performance of the device under test (DUT) is however required when testing with grid emulator since the characteristic of the grid emulator might influence the performance of the DUT. This paper focuses on the performance analysis of the DUT when tested using grid emulator. Beside the issue regarding the current harmonics, the performance during Fault Ride-Through (FRT) is discussed in detail. A power hardware in the loop setup is an attractive solution to conduct a comprehensive study on the interaction between the power-electronics converters and the electrical grids.

Report on field test project for wind power development at Nagashima-cho. Detailed wind characteristics survey; Nagashimacho ni okeru furyoku field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A detailed wind characteristics survey was conducted to study the feasibility of a wind power generation system for Nagashima-cho, Izumi-gun, Kagoshima Prefecture. Observation instruments were installed at the top of a hill approximately 80m above the sea level situated to the northwest of the Nagashima-cho town hall and, in the period October 1998 through September 1999, data were collected at a point 20m above ground, such as the average wind speed and direction, wind velocity standard deviation, and the maximum instantaneous wind velocity. The data were analyzed, and findings were obtained, as mentioned below. The annual average wind speed was 5.0m, strong in winter and weak in summer. The annual wind direction occurrence rate was 61.8%, turbulence intensity was 0.17 at wind speeds of 4m/s and more, these not presenting any particular problem. Wind energy density was 148W/m{sup 2}. Both wind speed conditions and energy density were slightly lower than the reference levels indicated for evaluation. Studies were made on the assumption that three classes of wind turbines (150, 300, and 750kW) would be introduced, and then it was found that both operating factors and facility availability rates exceeded the required levels. Since there were no detrimental factors in the surrounding conditions, it was concluded that possibilities were high that wind power generation at the site would be practical. (NEDO)

A spinner-integrated wind lidar for enhanced wind turbine control

DEFF Research Database (Denmark)

Mikkelsen, Torben; Angelou, Nikolas; Hansen, Kasper Hjorth

2013-01-01

A field test with a continuous wave wind lidar (ZephIR) installed in the rotating spinner of a wind turbine for unimpeded preview measurements of the upwind approaching wind conditions is described. The experimental setup with the wind lidar on the tip of the rotating spinner of a large 80 m roto...... of the spinner lidar data, is investigated. Finally, the potential for enhancing turbine control and performance based on wind lidar preview measurements in combination with feed-forward enabled turbine controllers is discussed. Copyright © 2012 John Wiley & Sons, Ltd....

Wind loads on flat plate photovoltaic array fields (nonsteady winds)

Science.gov (United States)

Miller, R. D.; Zimmerman, D. K.

1981-01-01

Techniques to predict the dynamic response and the structural dynamic loads of flat plate photovoltaic arrays due to wind turbulence were analyzed. Guidelines for use in predicting the turbulent portion of the wind loading on future similar arrays are presented. The dynamic response and the loads dynamic magnification factor of the two array configurations are similar. The magnification factors at a mid chord and outer chord location on the array illustrated and at four points on the chord are shown. The wind tunnel test experimental rms pressure coefficient on which magnification factors are based is shown. It is found that the largest response and dynamic magnification factor occur at a mid chord location on an array and near the trailing edge. A technique employing these magnification factors and the wind tunnel test rms fluctuating pressure coefficients to calculate design pressure loads due to wind turbulence is presented.

Wind power development field test project at Aoyama Heights, Aoyama-cho. Detailed wind characteristics survey; Aoyamacho Aoyama Kogen ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A detailed wind characteristics survey was conducted at Aoyama Heights, Aoyama-cho, Naga-gun, Mie Prefecture, on the assumption that a wind power generation system would be constructed. The survey was a 1-year project from October 1998 through September 1999, and wind characteristics such as the average wind speed, average wind direction, standard deviation of wind velocity, and the maximum instantaneous wind speed were observed. The observation point was fixed at 20m above ground, the minimum time unit for observation was 10 minutes, and the 10-minute average value was defined as the measured value. For the maximum instantaneous wind speed, the minimum time unit for observation was set to be 2 seconds. The yearly average wind speed was 5.3m/s and the maximum wind speed in the period was 32m/s. Winds came prevalently from WNW (31.6%), and then from NW (16.8%), ESE (20.9%), and E (9.9%). The wind axis was in the direction of WNW-ESE, and the total wind direction occurrence rate was 89.0%. Turbulence intensity was 0.25 at wind speed 2.0m/s or more and 0.23 at wind speed 4.0m/s or more. Estimated wind turbine yearly operating factors of 70-84% were obtained using rated values of a 150kW, 300kW, and 750kW-class wind turbines. (NEDO)

Tunel Blanka, tunel do historie Prahy

Czech Academy of Sciences Publication Activity Database

Herichová, Iva; Fridrichová-Sýkorová, Ivana; Tomková, Kateřina

2012-01-01

Roč. 21, č. 4 (2012), s. 66-73 ISSN 1211-0728 Institutional research plan: CEZ:AV0Z80020508 Keywords : rescue archaeological excavation * Prague * cemetery * Palaeolithic Subject RIV: AC - Archeology, Anthropology, Ethnology

Report on the field test project for wind power development at Yaku Town (wind characteristics investigation); Yakumachi ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-11-01

Wind characteristics are observed for a year at Yakushima Young Travellers' Village of the above-named town, Kagoshima Prefecture. The exponential index of the wind speed distribution in the vertical direction is between 1.6 and 4.7, or 3.5 on the average, relatively small due probably to the peculiar terrain and causing no trouble in the development. Turbulence intensity is 0.16 at when the wind speed is 2m/s or more, low enough to meet the reference value (0.30 or less). The total occurrence rate on the prevalent wind axis (SSE-NNW) is 48%, falling short of the reference value (60% or more). The average wind speed in the prevalent wind direction is high and the wind energy density concentrates on the prevalent wind axis, this showing that the site is good for wind power development. The annual average wind speed is 5.6m/s, slightly lower than the reference value (5.8m/s or more). Since there are possibilities of a maximum instantaneous wind speed of over 60m/s, caution is to be used in determining the wind endurance level for the wind turbine design. The annual wind energy density is 325W/m{sup 2}, fully meeting the reference value (215W/m{sup 2} or more). The annual operation rates of the 150/300/750kW wind turbine models are 61/65/80%, and these meet the reference value (45% or more). Their annual capacity ratios are 24.5/26.6/27.7%, and these again meet the reference value (17% or more). (NEDO)

Development of a Wind Turbine Test Rig and Rotor for Trailing Edge Flap Investigation: Static Flap Angles Case

International Nuclear Information System (INIS)

Abdelrahman, Ahmed; Johnson, David A

2014-01-01

One of the strategies used to improve performance and increase the life-span of wind turbines is active flow control. It involves the modification of the aerodynamic characteristics of a wind turbine blade by means of moveable aerodynamic control surfaces. Trailing edge flaps are relatively small moveable control surfaces placed at the trailing edge of a blade's airfoil that modify the lift of a blade or airfoil section. An instrumented wind turbine test rig and rotor were specifically developed to enable a wide-range of experiments to investigate the potential of trailing edge flaps as an active control technique. A modular blade based on the S833 airfoil was designed to allow accurate instrumentation and customizable settings. The blade is 1.7 meters long, had a constant 178mm chord and a 6° pitch. The modular aerodynamic parts were 3D printed using plastic PC-ABS material. The blade design point was within the range of wind velocities in the available large test facility. The wind facility is a large open jet wind tunnel with a maximum velocity of 11m/s in the test area. The capability of the developed system was demonstrated through an initial study of the effect of stationary trailing edge flaps on blade load and performance. The investigation focused on measuring the changes in flapwise bending moment and power production for different trailing edge flap spanwise locations and deflection angles. The relationship between the load reduction and deflection angle was linear as expected from theory and the highest reduction was caused by the flap furthest from the rotor center. Overall, the experimental setup proved to be effective in measuring small changes in flapwise bending moment within the wind turbine blade and will provide insight when (active) flap control is targeted

Report on the field test project for wind power development at Soyo Town (wind characteristics investigation); Soyomachi ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-11-01

Wind characteristics are observed for a year at Soyo Town, Aso-gun, Kumamoto Prefecture. The annual average wind speed is 5.9m/s and 5.6m/s at 20m and 10m above ground, respectively, satisfying the reference values of 5.6m/s and 5.0m/s. The prevalent wind direction is WNW (occurrence rate: 32.8%). The wind from the directions with WNW at their middle occupies 75%, stable and satisfying the reference value of 60%. Strong winds come frequently from the direction of high occurrence, which is advantageous in arranging plural wind turbine systems. The exponential index in the wind speed vertical distribution is 13.3, but wind distribution is not simple at a mountain top site like the observation station in this report. Wind characteristics are similar to those at places with mild inundations, and the maximum instantaneous wind speed of 40.8m/s will not pose a problem. The wind energy density is 205W/m{sup 2}, satisfying the reference value of 150. Wind power systems of 150kW, 300kW, and 750kW are assumed. When the exponential index is 13.3, their annual operation rates will be 70%, 71%, and 82%; and their capacity ratios are 22.6%, 23.9%, and 22.9%, all satisfying the reference values. They will collect 297MWh, 629MWh, and 1507MWh of wind energy per year. It is concluded that Soyo Town is fully qualified as a site for wind power development. (NEDO)

The Dutch wind tunnel guideline for wind loads

NARCIS (Netherlands)

Geurts, C.P.W.; Bentum, van C.A.; Willemsen, E.

2013-01-01

This paper addresses questions that arose during development and application of the Dutch guideline for wind tunnel testing to determine wind loads on buildings. This guideline (CUR 103) is being used since 2005, and a first revision is foreseen. Within this revision, the relation with Eurocode EN

Accionamiento de un ventilador industrial para prueba de aerogeneradores; Drive of an industrial fan for wind testing

Directory of Open Access Journals (Sweden)

Francisco Eneldo López Monteagudo

2015-04-01

Full Text Available En este trabajo se implementó el control de un ventilador industrial utilizado para prueba de aerogeneradores, el cual es empleado como un dispositivo interno en la elaboración de un túnel de viento, para realizar pruebas de medición de viento. El proyecto consistió en regular la velocidad de un ventilador industrial utilizado en un túnel de viento, para realizar pruebas de sistemas de control en aerogeneradores, generándose señales de viento reguladas en valores constantes, ó que sigan un perfil definido por una base de datos de valores reales medidos con un anemómetro. Para implementar el sistema de control y la comunicación de los dispositivos, se empleó un procesador digital de señales (PDS de Texas Instruments EZDSP2407, que actúa como interfaz para transmitir los datos entre el entorno de programación (VisSim Embedded Control Developer (ECD. Además se utilizó un variador de velocidad de 3HP de la marca SIEMENS modelo Micromaster 420. In this work, a fan control industrial wind turbines used for test, which is used as an internal device in the development of a wind tunnel for testing wind measurement. The project consists of regulating the speed of an industrial fan used in a wind tunnel to test control systems in wind turbines, wind generating regulated signals in constant, or to follow a profile defined by a database of values actual measured with an anemometer. To implement the control system and communication devices, in this project employed a digital signal processor (DSP from Texas Instruments EZDSP2407, which acts as an interface to transmit data between the programming environments (VisSim Embedded Control Developer (ECD. Also uses a variable speed 3HP SIEMENS Micromaster model 420.

Wind Loads on Structures

DEFF Research Database (Denmark)

Dyrbye, Claes; Hansen, Svend Ole

Wind loads have to be taken into account when designing civil engineering structures. The wind load on structures can be systematised by means of the wind load chain: wind climate (global), terrain (wind at low height), aerodynamic response (wind load to pressure), mechanical response (wind...... pressure to structural response) and design criteria. Starting with an introduction of the wind load chain, the book moves on to meteorological considerations, atmospheric boundary layer, static wind load, dynamic wind load and scaling laws used in wind-tunnel tests. The dynamic wind load covers vibrations...... induced by wind turbulence, vortex shedding, flutter and galloping. The book gives a comprehensive treatment of wind effects on structures and it will be useful for consulting engineers designing wind-sensitive structures. It will also be valuable for students of civil engineering as textbook...

Impact of relative position vehicle-wind blower in a roller test bench under climatic chamber

International Nuclear Information System (INIS)

Fernández-Yáñez, P.; Armas, O.; Martínez-Martínez, S.

2016-01-01

Highlights: • Air simulation model was developed for a vehicle test bench under climatic chamber. • Good accuracy between experimental data and simulated values were obtained. • Wind blower-vehicle relative position alters external cooling of after-treatment devices. • Vehicle emission certification can be affected by wind blower-vehicle relative position. - Abstract: In terms of energy efficiency and exhaust emissions control, an appropriate design of cooling systems of climatic chambers destined to vehicle certification and/or perform scientific research is becoming increasingly important. European vehicle emissions certification (New European Driving Cycle, NEDC) establishes the position of the wind-simulation blower at 200 mm above floor level. This height is fixed and kept constant independently of the vehicle tested. The position of the blower with respect to the vehicle can modify the external forced convection under the car, where after-treatment devices are located. Consequently, the performance of such devices could be modified and emission results during the certification cycle could be non-representative of real-world driving conditions. The aim of this work is to study the influence of different wind blower-vehicle relative heights on the air velocity and temperature profiles under the car by means of a simple computational fluid dynamics (CFD) approach. A steady state three-dimensional CFD model was developed and applied to the estimation of the air velocity and temperature profiles inside of a climatic chamber equipped with a vehicle roller (chassis dyno) test bench. The simulations reproduce one steady-state condition from NEDC, specifically the EU17 mode (120 km/h, maximum velocity during the cycle). The cool air propelling temperature was 20 °C (minimum temperature in the NEDC range). Simulations were performed employing the Reynolds-Averaged Navier-Stokes (RANS) approach with the realizable k-ε model to provide closure. Air velocity and

Wind power development field test project at Kodomari-mura 'Marinetopia'. Close survey on wind conditions; Kodomarimura Marinetopia ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A survey was made on wind conditions in Imabetsu-machi, Higashi Tsugaru-gun, Aomori prefecture, on the assumption that a wind power generation system was installed therein. The survey period was one year from Oct., 1998 to Sept., 1999. The observations were carried out on the average wind velocity, average wind direction, standard deviation of velocity, and the maximum instantaneous wind velocity. With a fixed point observation at 20 m above ground, and with the minimum observation time unit of 10 minutes, an average value during the 10 minutes was determined as the measurement of each category. However, the maximum instantaneous wind velocity was determined on the measurement with the minimum observation time unit of 2 seconds. The annual average wind velocity was 4.8 m/s, the maximum wind velocity during the period was 35 m/s, the prevailing wind direction was NW-WNW and ESE-SEW, and the occurrence rate of wind direction at the wind axis of NW-SE was 88.1%. The intensity of turbulence was 0.24 at a wind velocity of 2.0 m/s or above and was 0.20 at 4.0 m/s or above. An estimated annual operation rate of a windmill was 46-64% using the rated value of a 150 kW, 300 kW and 750 kW class windmills. (NEDO)

Stochastic Analysis of Wind Energy for Wind Pump Irrigation in Coastal Andhra Pradesh, India

Science.gov (United States)

Raju, M. M.; Kumar, A.; Bisht, D.; Rao, D. B.

2014-09-01

The rapid escalation in the prices of oil and gas as well as increasing demand for energy has attracted the attention of scientists and researchers to explore the possibility of generating and utilizing the alternative and renewable sources of wind energy in the long coastal belt of India with considerable wind energy resources. A detailed analysis of wind potential is a prerequisite to harvest the wind energy resources efficiently. Keeping this in view, the present study was undertaken to analyze the wind energy potential to assess feasibility of the wind-pump operated irrigation system in the coastal region of Andhra Pradesh, India, where high ground water table conditions are available. The stochastic analysis of wind speed data were tested to fit a probability distribution, which describes the wind energy potential in the region. The normal and Weibull probability distributions were tested; and on the basis of Chi square test, the Weibull distribution gave better results. Hence, it was concluded that the Weibull probability distribution may be used to stochastically describe the annual wind speed data of coastal Andhra Pradesh with better accuracy. The size as well as the complete irrigation system with mass curve analysis was determined to satisfy various daily irrigation demands at different risk levels.

Fundamentals for remote structural health monitoring of wind turbine blades - a pre-project. Annex D - Full-scale test of wind turbine blade, using sensors and NDT

Energy Technology Data Exchange (ETDEWEB)

Kristensen, O.J.D.; McGugan, M.; Sendrup, P.; Rheinlaender, J.; Rusborg, J.; Hansen, A.M.; Debel, C.P.; Soerensen, B.F.

2002-05-01

A 19.1 metre wind turbine blade was subjected to static tests. The purpose of the test series was to verify the abilities of different types of sensors to detect damage in wind turbine blades. Prior to each of the static test-series an artificial damage was made on the blade. The damage made for each test-series was surveyed during each series by acoustic emission, fiber optic micro bend displacement transducers and strain gauges. The propagation of the damage was determined by use of ultra sonic and X-ray surveillance during stops in the test series. By use of acoustic emission it was possible to measure damage propagation before the propagation was of visible size. By use of fiber optic micro bend displacement transducers and strain gauges it was possible to measure minor damage propagation. By use of both ultra sonic, and X-ray NDT-equipment it were possible to determine the size of propagated damage. (au)

Design of Linear Control System for Wind Turbine Blade Fatigue Testing

DEFF Research Database (Denmark)

Toft, Anders; Roe-Poulsen, Bjarke Nørskov; Christiansen, Rasmus

2016-01-01

This paper proposes a linear method for wind turbine blade fatigue testing at Siemens Wind Power. The setup consists of a blade, an actuator (motor and load mass) that acts on the blade with a sinusoidal moment, and a distribution of strain gauges to measure the blade flexure. Based...... difficult to control. To make a linear controller, a different approach has been chosen, namely making a controller which is not regulating on the input frequency, but on the input amplitude. A non-linear mechanical model for the blade and the motor has been constructed. This model has been simplified based...... on the desired output, namely the amplitude of the blade. Furthermore, the model has been linearised to make it suitable for linear analysis and control design methods.\\\\ The controller is designed based on a simplified and linearised model, and its gain parameter determined using pole placement. The model...

Wind-tunnel Tests of a Hall High-life Wing

Science.gov (United States)

Weick, Fred E; Sanders, Robert

1932-01-01

Wind-tunnel tests have been made to find the lift, drag, and center-of-pressure characteristics of a Hall high-lift wing model. The Hall wing is essentially a split-flap airfoil with an internal air passage. Air enters the passage through an opening in the lower surface somewhat back of and parallel to the leading edge, and flows out through an opening made by deflecting the rear portion of the under surface downward as a flap. For ordinary flight conditions the front opening and the rear flap can be closed, providing in effect a conventional airfoil (the Clark Y in this case). The tests were made with various flap settings and with the entrance to the passage both open and closed. The highest lift coefficient found, C(sub L) = 2.08, was obtained with the passage closed.

Correaltion of full-scale drag predictions with flight measurements on the C-141A aircraft. Phase 2: Wind tunnel test, analysis, and prediction techniques. Volume 1: Drag predictions, wind tunnel data analysis and correlation

Science.gov (United States)

Macwilkinson, D. G.; Blackerby, W. T.; Paterson, J. H.

1974-01-01

The degree of cruise drag correlation on the C-141A aircraft is determined between predictions based on wind tunnel test data, and flight test results. An analysis of wind tunnel tests on a 0.0275 scale model at Reynolds number up to 3.05 x 1 million/MAC is reported. Model support interference corrections are evaluated through a series of tests, and fully corrected model data are analyzed to provide details on model component interference factors. It is shown that predicted minimum profile drag for the complete configuration agrees within 0.75% of flight test data, using a wind tunnel extrapolation method based on flat plate skin friction and component shape factors. An alternative method of extrapolation, based on computed profile drag from a subsonic viscous theory, results in a prediction four percent lower than flight test data.

Acoustic Modifications of the Ames 40x80 Foot Wind Tunnel and Test Techniques for High-Speed Research Model Testing

Science.gov (United States)

Soderman, Paul T.; Olson, Larry (Technical Monitor)

1995-01-01

The NFAC 40- by 80- Foot Wind Tunnel at Ames is being refurbished with a new, deep acoustic lining in the test section which will make the facility nearly anechoic over a large frequency range. The modification history, key elements, and schedule will be discussed. Design features and expected performance gains will be described. Background noise reductions will be summarized. Improvements in aeroacoustic research techniques have been developed and used recently at NFAC on several wind tunnel tests of High Speed Research models. Research on quiet inflow microphones and struts will be described. The Acoustic Survey Apparatus in the 40x80 will be illustrated. A special intensity probe was tested for source localization. Multi-channel, high speed digital data acquisition is now used for acoustics. And most important, phased microphone arrays have been developed and tested which have proven to be very powerful for source identification and increased signal-to-noise ratio. Use of these tools for the HEAT model will be illustrated. In addition, an acoustically absorbent symmetry plane was built to satisfy the HEAT semispan aerodynamic and acoustic requirements. Acoustic performance of that symmetry plane will be shown.

Analysis of the imbalance price scheme in the Spanish electricity market: A wind power test case

International Nuclear Information System (INIS)

Bueno-Lorenzo, Miriam; Moreno, M. Ángeles; Usaola, Julio

2013-01-01

This work investigates the interaction between wind power and electricity markets. The paper is focused on balancing markets pricing policies. The proposal of a new imbalance price scheme is included and conveniently evaluated. This proposed scheme tries to minimise the use of ancillary services to compensate for deviations in searching for a more efficient market design. The effectiveness of imbalance prices as market signals is also examined, and policy recommendations regarding imbalance services are discussed. Two test cases are included that analyse the participation of a wind power producer in the Spanish electricity market using a stochastic optimisation strategy. For this purpose, the uncertainty of the variables is considered, i.e., wind power production and prediction, intraday and imbalance prices. Test cases were run with real data for 10 months, and realistic results are presented along with a hypothetical test case. The regulation of the imbalance prices may not be adequate for the Spanish electricity market because an error drop is not sufficiently encouraged. Therefore, we suggest the application of a new imbalance price scheme, which includes an additional constraint. The conclusions of this paper can be assumed to be general policy recommendations

Wind Energy Department annual progress report 2002

Energy Technology Data Exchange (ETDEWEB)

Johansen, B.D.; Riis, U. (eds.)

2003-12-01

Research and development activities of the Wind Energy Department range from boundary layer meteorology, fluid dynamics, and structural mechanics to power and control engineering as well as wind turbine loading and safety. The overall purpose of our work is to meet the needs for knowledge, methods and procedures from government, the scientific community, and the wind turbine industry in particular. Our assistance to the wind turbine manufacturers serve to pave the way for technological development and thus further the exploitation of wind energy worldwide. We do this by means of research and innovation, education, testing and consultancy. In providing services for the wind turbine industry, we are involved in technology development, design, testing, procedures for operation and maintenance, certification and international wind turbine projects s as well as the solution of problems encountered in the application of wind energy, e.g. grid connection. A major proportion of these activities are on a commercial basis, for instance consultancy, software development, accredited testing of wind turbines and blades as well as approval and certification in co-operation with Det Norske Veritas. The departments activities also include research into atmospheric physics and environmental issues related to the atmosphere. One example is the development of online warning systems for airborne bacteria and other harmful substances. The department is organized in programmes according to its main scientific and technical activities. Research programmes: 1) Aeroelastic Design, AED; 2) Atmospheric Phyrics, ATM; 3) Electrical DEsign and Control, EDS; 4) Wind Power Meteorology, VKM; 5) Wind Turbines, VIM; 6) Wind Turbine Diagnostics, VMD. Commercial programmes: 1) The Test Station for Large Wind Turbines, Hoevsoere, HOeV; 2) Risoe Wind Consult, INR; 3) Wind Turbine Testing; 4) Sparkaer Blade Test Centre.(au)

Characterization of wind velocities in the wake of a full scale wind turbine using three ground-based synchronized WindScanners

DEFF Research Database (Denmark)

Yazicioglu, Hasan; Angelou, Nikolas; Mikkelsen, Torben Krogh

2016-01-01

The wind energy community is in need of detailed full-field measurements in the wake of wind turbines. Here, three dimensional(3D) wind vector field measurements obtained in the near-wake region behind a full-scale test turbine are presented. Specifically, the wake of a NEG Nordtank turbine...

Characterization of a Power Electronic Grid Simulator for Wind Turbine Generator Compliance Testing

DEFF Research Database (Denmark)

Glasdam, Jakob Bærholm; Gevorgian, V.; Wallen, R.

2014-01-01

This paper presents the commissioning results and testing capabilities of a multi-megawatt power electronic grid simulator situated in National Renewable Energy Laboratory’s (NREL’s) new testing facility. The commissioning is done using a commercial type 4 multi-megawatt sized wind turbine...... generator (WTG) installed in NREL’s new 5 MW dynamometer and a kilowatt sized type 1 WTG connected to the existing 2.5 MW dynamometer at NREL. The paper demonstrates the outstanding testing capability of the grid simulator and its application in the grid code compliance evaluation of WTGs including balanced...

Photogrammetry Applied to Wind Tunnel Testing

Science.gov (United States)

Liu, Tian-Shu; Cattafesta, L. N., III; Radeztsky, R. H.; Burner, A. W.

2000-01-01

In image-based measurements, quantitative image data must be mapped to three-dimensional object space. Analytical photogrammetric methods, which may be used to accomplish this task, are discussed from the viewpoint of experimental fluid dynamicists. The Direct Linear Transformation (DLT) for camera calibration, used in pressure sensitive paint, is summarized. An optimization method for camera calibration is developed that can be used to determine the camera calibration parameters, including those describing lens distortion, from a single image. Combined with the DLT method, this method allows a rapid and comprehensive in-situ camera calibration and therefore is particularly useful for quantitative flow visualization and other measurements such as model attitude and deformation in production wind tunnels. The paper also includes a brief description of typical photogrammetric applications to temperature- and pressure-sensitive paint measurements and model deformation measurements in wind tunnels.

Power-hardware-in-the-loop test of VSC-HVDC connection for off-shore wind power plants

Energy Technology Data Exchange (ETDEWEB)

Sharma, Ranjan [Siemens Wind Power A/S, Brande (Denmark); Technical Univ. of Denmark (Denmark). Center for Electric Technology; Cha, Seung T.; Wu, Qiuwei; Rasmussen, Tonny W.; Oestergaard, Jacob [Technical Univ. of Denmark (Denmark). Center for Electric Technology; Jensen, Kim H. [Siemens Wind Power A/S, Brande (Denmark)

2011-07-01

This paper present a power-hardware-in-the-loop (PHIL) test of an off-shore wind power plant (WPP) interconnected to the on-shore grid via a VSC-HVDC connection. The intention of the PHIL test is to verify the hardware interaction and the control co-ordination between the plant side VSC of the HVDC system and the wind turbines within the WPP in order to ensure smooth operation of the WPP under both normal and fault operating condition. The PHIL test platform is comprised of a real time digital simulator (RTDS), a Spitzenberger Spies three phase 7,5 kW power amplifier, a purpose built VSC and a DC chopper. The WPP is simulated in the RTDS as a single full-scale wind turbine. The simulated WPP interacts with the WPP side VSC through the power amplifier. The interface between the RTDS and the power amplifier is done via an analogue GTAO I/O card of the RTDS and the input channel of the amplifier. The amplifier scales up the voltages at the point of connection of the WPP in the RTDS to the voltage level for the WPP side VSC. The WPP side VSC converter is equipped with a DC chopper. The test results show the successful control coordination between the WPP and the plant side VSC converter of the HVDC connection of the WPP. (orig.)

Next Generation Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Cheraghi, S. Hossein [Western New England Univ., Springfield, MA (United States); Madden, Frank [FloDesign Wind Turbine Corp., Waltham, MA (United States)

2012-09-01

The goal of this collaborative effort between Western New England University's College of Engineering and FloDesign Wind Turbine (FDWT) Corporation to wok on a novel areodynamic concept that could potentially lead to the next generation of wind turbines. Analytical studies and early scale model tests of FDWT's Mixer/Ejector Wind Turbine (MEWT) concept, which exploits jet-age advanced fluid dynamics, indicate that the concept has the potential to significantly reduce the cost of electricity over conventional Horizontal Axis Wind Turbines while reducing land usage. This project involved the design, fabrication, and wind tunnel testing of components of MEWT to provide the research and engineering data necessary to validate the design iterations and optimize system performance. Based on these tests, a scale model prototype called Briza was designed, fabricated, installed and tested on a portable tower to investigate and improve the design system in real world conditions. The results of these scale prototype efforts were very promising and have contributed significantly to FDWT's ongoing development of a product scale wind turbine for deployment in multiple locations around the U.S. This research was mutually beneficial to Western New England University, FDWT, and the DOE by utilizing over 30 student interns and a number of faculty in all efforts. It brought real-world wind turbine experience into the classroom to further enhance the Green Engineering Program at WNEU. It also provided on-the-job training to many students, improving their future employment opportunities, while also providing valuable information to further advance FDWT's mixer-ejector wind turbine technology, creating opportunities for future project innovation and job creation.

Wind power development field test project at Rokkasho-mura, Aomori prefecture. Close survey on wind conditions; Aomoriken Rokkashomura ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A survey was made on wind conditions in Rokkasho-mura, Kamikita-gun, Aomori prefecture, on the assumption that a wind power generation system was installed therein. The survey period was one year from Oct., 1998 to Sept., 1999. The observations were carried out on the average wind velocity, average wind direction, standard deviation of velocity, and the maximum instantaneous wind velocity. With a fixed point observation at 20 m above ground, and with the minimum observation time unit of 10 minutes, an average value during the 10 minutes was determined as the measurement of each category. However, the maximum instantaneous wind velocity was determined on the measurement with the minimum observation time unit of 2 seconds. The annual average wind velocity was 4.6 m/s, the maximum wind velocity during the period was 26.0 m/s, the prevailing wind direction was NW (20.8%), WNW (18.0%), and SE (13.5%), and the total occurrence rate of wind direction at the wind axis of NW-SE was 75.7%. The intensity of turbulence was 0.25 at a wind velocity of 2.0 m/s or above and was 0.21 at 4.0 m/s or above. An estimated annual operation rate of a windmill was 59-72% using the rated value of a 150 kW, 300 kW and 750 kW class windmills. (NEDO)

Preliminary Design of a LSA Aircraft Using Wind Tunnel Tests

Directory of Open Access Journals (Sweden)

Norbert ANGI

2015-12-01

Full Text Available This paper presents preliminary results concerning the design and aerodynamic calculations of a light sport aircraft (LSA. These were performed for a new lightweight, low cost, low fuel consumption and long-range aircraft. The design process was based on specific software tools as Advanced Aircraft Analysis (AAA, XFlr 5 aerodynamic and dynamic stability analysis, and Catia design, according to CS-LSA requirements. The calculations were accomplished by a series of tests performed in the wind tunnel in order to assess experimentally the aerodynamic characteristics of the airplane.

A multi-frequency fatigue testing method for wind turbine rotor blades

DEFF Research Database (Denmark)

Eder, Martin Alexander; Belloni, Federico; Tesauro, Angelo

2017-01-01

Rotor blades are among the most delicate components of modern wind turbines. Reliability is a crucial aspect, since blades shall ideally remain free of failure under ultra-high cycle loading conditions throughout their designated lifetime of 20–25 years. Full-scale blade tests are the most accurate...... means to experimentally simulate damage evolution under operating conditions, and are therefore used to demonstrate that a blade type fulfils the reliability requirements to an acceptable degree of confidence. The state-of-the-art testing method for rotor blades in industry is based on resonance...... higher modes contribute more significantly due to their higher cycle count. A numerical feasibility study based on a publicly available large utility rotor blade is used to demonstrate the ability of the proposed approach to outperform the state-of-the-art testing method without compromising fatigue test...

Endurance Wind Power : practical insights into small wind

International Nuclear Information System (INIS)

Hicks, D.

2008-01-01

This presentation discussed practical issues related to purchasing and installing small wind turbines in Canada. Wind power capacity can be estimated by looking at provincial wind maps as well as by seeking wind data at local airports. Wind resources are typically measured at heights of between 20 meters and 50 m. The height of a wind turbine tower can significantly increase the turbine's wind generating capacity. Turbine rotors should always be placed 30 feet higher than obstacles within 500 feet. Many provinces have now mandated utilities to accept renewable energy resources from grid-connected wind energy plants. Net billing systems are used to determine the billing relationship between power-producing consumers and the utilities who will buy the excess power and sell it to other consumers. Utilities are not yet mandated to purchase excess power, and it is likely that federal and provincial legislation will be needed to ensure that net billing systems continue to grow. Many Canadian municipalities have no ordinances related to wind turbine placements. Consumers interested in purchasing small wind turbines should ensure that the turbine has been certified by an accredited test facility and has an adequate safety system. The noise of the turbine as well as its power performance in relation to the purchaser's needs must also be considered. It was concluded that small wind turbines can provide a means for electricity consumers to reduce their carbon footprint and hedge against the inflationary costs of fossil-fuelled energy resources. tabs., figs

Modeling and Operational Testing of an Isolated Variable Speed PMSG Wind Turbine with Battery Energy Storage

Directory of Open Access Journals (Sweden)

BAROTE, L.

2012-05-01

Full Text Available This paper presents the modeling and operational testing of an isolated permanent magnet synchronous generator (PMSG, driven by a small wind turbine with a battery energy storage system during wind speed and load variations. The whole system is initially modeled, including the PMSG, the boost converter and the storage system. The required power for the connected loads can be effectively delivered and supplied by the proposed wind turbine and energy storage systems, subject to an appropriate control method. Energy storage devices are required for power balance and power quality in stand alone wind energy systems. The main purpose is to supply 230 V / 50 Hz domestic appliances through a single-phase inverter. The experimental waveforms, compared to the simulation results, show a good prediction of the electrical variable parameters. Furthermore, it can be seen that the results validate the stability of the supply.

Self streamlining wind tunnel: Further low speed testing and final design studies for the transonic facility

Science.gov (United States)

Wolf, S. W. D.

1978-01-01

Work was continued with the low speed self streamlining wind tunnel (SSWT) using the NACA 0012-64 airfoil in an effort to explain the discrepancies between the NASA Langley low turbulence pressure tunnel (LTPT) and SSWT results obtained with the airfoil stalled. Conventional wind tunnel corrections were applied to straight wall SSWT airfoil data, to illustrate the inadequacy of standard correction techniques in circumstances of high blockage. Also one SSWT test was re-run at different air speeds to investigate the effects of such changes (perhaps through changes in Reynold's number and freestream turbulence levels) on airfoil data and wall contours. Mechanical design analyses for the transonic self-streamlining wind tunnel (TSWT) were completed by the application of theoretical airfoil flow field data to the elastic beam and streamline analysis. The control system for the transonic facility, which will eventually allow on-line computer operation of the wind tunnel, was outlined.

Wind energy information guide

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-04-01

This book is divided into nine chapters. Chapters 1--8 provide background and annotated references on wind energy research, development, and commercialization. Chapter 9 lists additional sources of printed information and relevant organizations. Four indices provide alphabetical access to authors, organizations, computer models and design tools, and subjects. A list of abbreviations and acronyms is also included. Chapter topics include: introduction; economics of using wind energy; wind energy resources; wind turbine design, development, and testing; applications; environmental issues of wind power; institutional issues; and wind energy systems development.

Development and Operation of an Automatic Rotor Trim Control System for use During the UH-60 Individual Blade Control Wind Tunnel Test

Science.gov (United States)

Theodore, Colin R.

2010-01-01

A full-scale wind tunnel test to evaluate the effects of Individual Blade Control (IBC) on the performance, vibration, noise and loads of a UH-60A rotor was recently completed in the National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-Foot Wind Tunnel [1]. A key component of this wind tunnel test was an automatic rotor trim control system that allowed the rotor trim state to be set more precisely, quickly and repeatably than was possible with the rotor operator setting the trim condition manually. The trim control system was also able to maintain the desired trim condition through changes in IBC actuation both in open- and closed-loop IBC modes, and through long-period transients in wind tunnel flow. This ability of the trim control system to automatically set and maintain a steady rotor trim enabled the effects of different IBC inputs to be compared at common trim conditions and to perform these tests quickly without requiring the rotor operator to re-trim the rotor. The trim control system described in this paper was developed specifically for use during the IBC wind tunnel test

Report on the field test project for wind power development at Yugawara Town (wind characteristics investigation); Yugawaramachi ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-11-01

Wind characteristics are observed in the period November 1997 through October 1998 at Yugawara Town, Kanagawa Prefecture. The average wind speed is 5.1m/s and 5.0m/s at 20m and 10m above ground, respectively, suggesting that the difference in altitude causes but a very small difference in wind speed and that a large wind speed component exists in the vertical direction. Under the 16 compass point system, the wind direction occurrence rate is the highest in the NE direction and the second highest in the W direction. The two directions are prevalent, and their occurrence rates on the wind axes total 62.6%. The occurrence rate of wind speeds of not less than 5m/s is 40%. Turbulence intensity is 0.23 and 0.17 for the average wind speed of not less than 2m/s and for the average wind speed of not less than 4m/s, respectively, suggesting but a little impact of air current turbulence. The amounts of energy to be acquired by wind turbine systems of 150kW, 300kW, and 750kW are estimated at 301,363kWh, 651,593kWh, and 1,668,825kWh, respectively. Their annual capacity ratios are 22.9%, 24.8%, and 25.4%, respectively. Since difference in wind speed due to difference in altitude is small, it is supposed that the wind speed at the hub altitude is not so high. It is inferred consequently that service operation will be quite difficult to realize. Difficulties will be also encountered in relation to the route of turbine system transportation, power distribution line, and the distance to a transformation station. (NEDO)

Full-Span Tiltrotor Aeroacoustic Model (TRAM) Overview and 40- by 80-Foot Wind Tunnel Test. [conducted in the 40- by 80-Foot Wind Tunnel at Ames Research Center

Science.gov (United States)

McCluer, Megan S.; Johnson, Jeffrey L.; Rutkowski, Michael (Technical Monitor)

2001-01-01

Most helicopter data trends cannot be extrapolated to tiltrotors because blade geometry and aerodynamic behavior, as well as rotor and fuselage interactions, are significantly different for tiltrotors. A tiltrotor model has been developed to investigate the aeromechanics of tiltrotors, to develop a comprehensive database for validating tiltrotor analyses, and to provide a research platform for supporting future tiltrotor designs. The Full-Span Tiltrotor Aeroacoustic Model (FS TRAM) is a dual-rotor, powered aircraft model with extensive instrumentation for measurement of structural and aerodynamic loads. This paper will present the Full-Span TRAM test capabilities and the first set of data obtained during a 40- by 80-Foot Wind Tunnel test conducted in late 2000 at NASA Ames Research Center. The Full-Span TRAM is a quarter-scale representation of the V-22 Osprey aircraft, and a heavily instrumented NASA and U.S. Army wind tunnel test stand. Rotor structural loads are monitored and recorded for safety-of-flight and for information on blade loads and dynamics. Left and right rotor balance and fuselage balance loads are monitored for safety-of-flight and for measurement of vehicle and rotor aerodynamic performance. Static pressure taps on the left wing are used to determine rotor/wing interactional effects and rotor blade dynamic pressures measure blade airloads. All of these measurement capabilities make the FS TRAM test stand a unique and valuable asset for validation of computational codes and to aid in future tiltrotor designs. The Full-Span TRAM was tested in the NASA Ames Research Center 40- by 80-Foot Wind Tunnel from October through December 2000. Rotor and vehicle performance measurements were acquired in addition to wing pressures, rotor acoustics, and Laser Light Sheet (LLS) flow visualization data. Hover, forward flight, and airframe (rotors off) aerodynamic runs were performed. Helicopter-mode data were acquired during angle of attack and thrust sweeps for

Small Wind Research Turbine: Final Report

Energy Technology Data Exchange (ETDEWEB)

Corbus, D.; Meadors, M.

2005-10-01

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

Generation of electricity by wind power

Energy Technology Data Exchange (ETDEWEB)

Golding, E W

1976-01-01

Information on wind power is presented concerning the history of windmills; estimation of the energy obtainable from the wind; wind characteristics and distribution; wind power sites; wind surveys; wind flow over hills; measurement of wind velocity; wind structure and its determination; wind data and energy estimation; testing of wind driven ac generators; wind-driven machines; propeller type windmills; plants for isolated premises and small communities; economy of wind power generation; construction costs for large wind-driven generators; relationship of wind power to other power sources; research and development; and international cooperation.

The development and testing of a novel cross axis wind turbine

Science.gov (United States)

Chong, W. T.; Muzammil, W. K.; Gwani, M.; Wong, K. H.; Fazlizan, A.; Wang, C. T.; Poh, S. C.

2016-06-01

A novel cross axis wind turbine (CAWT) which comprises of a cross axis blades arrangement was presented and investigated experimentally. The CAWT is a new type of wind turbine that extracts wind energy from airflow coming from the horizontal and vertical directions. The wind turbine consists of three vertical blades and six horizontal blades arranged in a cross axis orientation. Hubs in the middle of the CAWT link the horizontal and vertical blades through connectors to form the CAWT. The study used a 45° deflector to guide the oncoming airflow upward (vertical wind direction). The results from the study showed that the CAWT produced significant improvements in power output and rotational speed performance compared to a conventional straight-bladed vertical axis wind turbine (VAWT).

Distributed Wind Competitiveness Improvement Project

Energy Technology Data Exchange (ETDEWEB)

2018-02-27

The Competitiveness Improvement Project (CIP) is a periodic solicitation through the U.S. Department of Energy and its National Renewable Energy Laboratory. The Competitiveness Improvement Project (CIP) is a periodic solicitation through the U.S. Department of Energy and its National Renewable Energy Laboratory. Manufacturers of small and medium wind turbines are awarded cost-shared grants via a competitive process to optimize their designs, develop advanced manufacturing processes, and perform turbine testing. The goals of the CIP are to make wind energy cost competitive with other distributed generation technology and increase the number of wind turbine designs certified to national testing standards. This fact sheet describes the CIP and funding awarded as part of the project.ufacturers of small and medium wind turbines are awarded cost-shared grants via a competitive process to optimize their designs, develop advanced manufacturing processes, and perform turbine testing. The goals of the CIP are to make wind energy cost competitive with other distributed generation technology and increase the number of wind turbine designs certified to national testing standards. This fact sheet describes the CIP and funding awarded as part of the project.

TOPFARM wind farm optimization tool

DEFF Research Database (Denmark)

Réthoré, Pierre-Elouan; Fuglsang, Peter; Larsen, Torben J.

A wind farm optimization framework is presented in detail and demonstrated on two test cases: 1) Middelgrunden and 2) Stags Holt/Coldham. A detailed flow model describing the instationary flow within a wind farm is used together with an aeroelastic model to determine production and fatigue loading...... of wind farm wind turbines. Based on generic load cases, the wind farm production and fatigue evaluations are subsequently condensed in a large pre-calculated database for rapid calculation of lifetime equivalent loads and energy production in the optimization loop.. The objective function defining....... The Middelgrunden test case resulted in an improvement of the financial balance of 2.1 M€ originating from a very large increase in the energy production value of 9.3 M€ mainly counterbalanced by increased electrical grid costs. The Stags Holt/Coldham test case resulted in an improvement of the financial balance...

Testing a ground-based canopy model using the wind river canopy crane

Science.gov (United States)

Robert Van Pelt; Malcolm P. North

1999-01-01

A ground-based canopy model that estimates the volume of occupied space in forest canopies was tested using the Wind River Canopy Crane. A total of 126 trees in a 0.25 ha area were measured from the ground and directly from a gondola suspended from the crane. The trees were located in a low elevation, old-growth forest in the southern Washington Cascades. The ground-...

Development and Operation of an Automatic Rotor Trim Control System for the UH-60 Individual Blade Control Wind Tunnel Test

Science.gov (United States)

Theodore, Colin R.; Tischler, Mark B.

2010-01-01

An automatic rotor trim control system was developed and successfully used during a wind tunnel test of a full-scale UH-60 rotor system with Individual Blade Control (IBC) actuators. The trim control system allowed rotor trim to be set more quickly, precisely and repeatably than in previous wind tunnel tests. This control system also allowed the rotor trim state to be maintained during transients and drift in wind tunnel flow, and through changes in IBC actuation. The ability to maintain a consistent rotor trim state was key to quickly and accurately evaluating the effect of IBC on rotor performance, vibration, noise and loads. This paper presents details of the design and implementation of the trim control system including the rotor system hardware, trim control requirements, and trim control hardware and software implementation. Results are presented showing the effect of IBC on rotor trim and dynamic response, a validation of the rotor dynamic simulation used to calculate the initial control gains and tuning of the control system, and the overall performance of the trim control system during the wind tunnel test.

Field Test Results of Using a Nacelle-Mounted Lidar for Improving Wind Energy Capture by Reducing Yaw Misalignment (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Fleming, P.; Scholbrock, A.; Wright, A.

2014-11-01

Presented at the Nordic Wind Power Conference on November 5, 2014. This presentation describes field-test campaigns performed at the National Wind Technology Center in which lidar technology was used to improve the yaw alignment of the Controls Advanced Research Turbine (CART) 2 and CART3 wind turbines. The campaigns demonstrated that whether by learning a correction function to the nacelle vane, or by controlling yaw directly with the lidar signal, a significant improvement in power capture was demonstrated.

Experimental tests of the effect of rotor diameter ratio and blade number to the cross-flow wind turbine performance

Science.gov (United States)

Susanto, Sandi; Tjahjana, Dominicus Danardono Dwi Prija; Santoso, Budi

2018-02-01

Cross-flow wind turbine is one of the alternative energy harvester for low wind speeds area. Several factors that influence the power coefficient of cross-flow wind turbine are the diameter ratio of blades and the number of blades. The aim of this study is to find out the influence of the number of blades and the diameter ratio on the performance of cross-flow wind turbine and to find out the best configuration between number of blades and diameter ratio of the turbine. The experimental test were conducted under several variation including diameter ratio between outer and inner diameter of the turbine and number of blades. The variation of turbine diameter ratio between inner and outer diameter consisted of 0.58, 0.63, 0.68 and 0.73 while the variations of the number of blades used was 16, 20 and 24. The experimental test were conducted under certain wind speed which are 3m/s until 4 m/s. The result showed that the configurations between 0.68 diameter ratio and 20 blade numbers is the best configurations that has power coefficient of 0.049 and moment coefficient of 0.185.

Husum wind `97. Amiable and powerful. Proceedings; Husum Wind `97. Liebenswert und leistungsstark. Kongressband

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

The Husum Fair and Congress on Wind Energy 97 wants to inform on and demonstrate the state of the art of wind energy and its potentials of development. This conference volume contains 21 papers in seven sections: Wind energy - society and environment; forum of the wind power plant manufacturers represented at the Husum Wind 97; foreign markets for wind power plants; development prospects for wind power; wind power in retrospective and relevant operating experience; panel discussion ``The amendment to the act on remuneration for power fed into the mains - wind power in the lull``; excursion to the test field WINDTEST, Kaiser-Wilhelm-Koog. (AKF)

Trading wind generation from short-term probabilistic forecasts of wind power

DEFF Research Database (Denmark)

Pinson, Pierre; Chevallier, Christophe; Kariniotakis, Georges

2007-01-01

Due to the fluctuating nature of the wind resource, a wind power producer participating in a liberalized electricity market is subject to penalties related to regulation costs. Accurate forecasts of wind generation are therefore paramount for reducing such penalties and thus maximizing revenue......, as well as on modeling of the sensitivity a wind power producer may have to regulation costs. The benefits resulting from the application of these strategies are clearly demonstrated on the test case of the participation of a multi-MW wind farm in the Dutch electricity market over a year....... participation. Such strategies permit to further increase revenues and thus enhance competitiveness of wind generation compared to other forms of dispatchable generation. This paper formulates a general methodology for deriving optimal bidding strategies based on probabilistic forecasts of wind generation...

Advisory Committee Societal and Environmental Aspects Test Wind Farm Oosterbierum. Adviescommissie Maatschappelijke en Milieu-Aspecten Proefwindpark Oosterbierum (NL); Eindrapportage van de onderzoeksresultaten

Energy Technology Data Exchange (ETDEWEB)

1992-12-01

An overview is given of the results of research on the title wind farm. The test wind turbine array consists of 3 rows of six 300 kW horizontal axis turbines, with an axis height of 35 meters, and a rotor diameter of 30 meters. The purpose of the test wind farm was to gain experience with regard to planning aspects, environmental aspects (flora and fauna) and societal acceptation and perception. The title committee (AMMA, abbreviated in Dutch) was installed in 1982 with the purpose to formulate the problems and research proposals, to advise research bureaus and institutes on the sub-studies, and to evaluate the results of the surveys and studies and to assess the possibility of using wind energy within the electric power supply in the Netherlands. All seven sub-studies, started by AMMA, are described briefly: a study on the effects of the wind farm on birds, a study on the effect of the wind farm on traffic, attracted by the wind turbine array, a study on the impact of the wind turbines on the agricultural management, an analysis of the effects on the landscape, a study on the visual perception of the wind turbines, a social-psychological study or the societal acceptation of wind power plants, and a study on the effects of surrounding objects on the wind availability for wind farms. If wind energy must contribute to the Dutch power supply as planned, many energy efficient and profitable wind turbines have to be installed in the Netherlands, excluding the areas which are important for birds or recreational areas. 4 figs., 28 refs.

Design and Wind Tunnel Testing of a Thick, Multi-Element High-Lift Airfoil

DEFF Research Database (Denmark)

Zahle, Frederik; Gaunaa, Mac; Sørensen, Niels N.

2012-01-01

In this work a 2D CFD solver has been used to optimize the shape of a leading edge slat with a chord length of 30% of the main airfoil which was 40% thick. The airfoil configuration was subsequently tested in a wind tunnel and compared to numerical predictions. The multi-element airfoil was predi...

Wind class sampling of satellite SAR imagery for offshore wind resource mapping

DEFF Research Database (Denmark)

Badger, Merete; Badger, Jake; Nielsen, Morten

2010-01-01

developed for mesoscale modeling of wind resources. Its performance in connection with sampling of SAR scenes is tested against two sets of random SAR samples and meteorological observations at three sites in the North Sea during 2005–08. Predictions of the mean wind speed and the Weibull scale parameter......High-resolution wind fields retrieved from satellite synthetic aperture radar (SAR) imagery are combined for mapping of wind resources offshore where site measurements are costly and sparse. A new sampling strategy for the SAR scenes is introduced, based on a method for statistical......-dynamical downscaling of large-scale wind conditions using a set of wind classes that describe representative wind situations. One or more SAR scenes are then selected to represent each wind class and the classes are weighted according to their frequency of occurrence. The wind class methodology was originally...

Power reserve provision with wind farms. Grid integration of wind power

Energy Technology Data Exchange (ETDEWEB)

Gesino, Alejandro J.

2011-07-01

Wind power is, admittedly, different from other power technologies and integrating large amounts of it in the existing power systems is a challenge that requires innovative approaches to keep the sustainability of the power system operation. In the coming years its contribution to the system security will become mandatory as far as the trend goes towards more decentralized structures and an increase in complexity due to a higher number of market participants. This PhD addresses one of the fundamental ancillary services researching about a secure and flexible methodology for power reserve provision with wind farms. Based on the current needs and security standards of those highly developed European grid codes, a new model for power reserve provision with wind power is developed. This methodology, algorithms and variables are tested based on real scenarios from five German wind farm clusters. Finally, once the methodology for power reserve provision with wind power has been tested, real control capabilities from already installed wind farms in Germany and Portugal are analyzed. Their capabilities of following control commands as well as an error deviation analysis are also presented. (orig.)

Design and test of box girder for a large wind turbine blade

DEFF Research Database (Denmark)

Nielsen, Per Hørlyk; Tesauro, Angelo; Bitsche, Robert

This report is covering the structural design and full scale test of a box girder as a part of the project “Demonstration of new blade design using manufacturing process simulations” supported by the EUDP program. A box girder with a predetermined outer geometry was designed using new inventions...... that the manufacturing process could include the new inventions. Subsequently the box girder was transported to the blade test facility at DTU Wind Energy. A series of test was performed with the blade to investigate the behaviour during loading, and finally the girder was loaded to ultimate failure. The report includes...... the description of the test setup, the test and an overview over the results from the test performed on the box girder. During the final test the box girder failed at 58 % of the expected ultimate load. Unfortunately, no definite conclusion could be made concerning the failure mechanism....

Strength and fatigue testing of large size wind turbines rotors. Vol. II: Full size natural vibration and static strength test, a reference case

Energy Technology Data Exchange (ETDEWEB)

Arias, F.; Soria, E.

1996-12-01

This report shows the methods and procedures selected to define a strength test for large size wind turbine, anyway in particular it application on a 500 kW blade and it results obtained in the test carried out in july of 1995 in Asinel`s test plant (Madrid). Henceforth, this project is designed in an abbreviate form whit the acronym SFAT. (Author)

Strength and fatigue testing of large size wind turbines rotors. Volume II. Full size natural vibration and static strength test, a reference case

International Nuclear Information System (INIS)

Arias, F.; Soria, E.

1996-01-01

This report shows the methods and procedures selected to define a strength test for large size wind turbine, anyway in particularly it application on a 500 kW blade and it results obtained in the test carried out in july of 1995 in Asinel test plant (Madrid). Henceforth, this project is designed in an abbreviate form whit the acronym SFAT. (Author)

An investigation of drag reduction for tractor trailer vehicles with air deflector and boattail. [wind tunnel tests

Science.gov (United States)

Muirhead, V. U.

1981-01-01

A wind tunnel investigation was conducted to determine the influence of several physical variables on the aerodynamic drag of a trailer model. The physical variables included: a cab mounted wind deflector, boattail on trailer, flow vanes on trailer front, forced transition on trailer, and decreased gap between tractor and trailer. Tests were conducted at yaw angles (relative wind angles) of 0, 5, 10, 20, and 30 degrees and Reynolds numbers of 3.58 x 10 to the 5th power 6.12 x 10 to the 5th power based upon the equivalent diameter of the vehicles. The wind deflector on top of the cab produced a calculated reduction in fuel consumption of about 5 percent of the aerodynamic portion of the fuel budget for a wind speed of 15.3 km/hr (9.5 mph) over a wind angle range of 0 deg to 180 deg and for a vehicle speed of 88.5 km/hr (55 mph). The boattail produced a calculated 7 percent to 8 percent reduction in fuel consumption under the same conditions. The decrease in gap reduced the calculated fuel consumption by about 5 percent of the aerodynamic portion of the fuel budget.

The VolturnUS 1:8 Floating Wind Turbine: Design, Construction, Deployment, Testing, Retrieval, and Inspection of the First Grid-Connected Offshore Wind Turbine in US

Energy Technology Data Exchange (ETDEWEB)

Dagher, Habib [Univ. of Maine, Orono, ME (United States); Viselli, Anthony [Univ. of Maine, Orono, ME (United States); Goupee, Andrew [Univ. of Maine, Orono, ME (United States); Kimball, Richard [Maine Maritime Academy, Castine, ME (United States); Allen, Christopher [Univ. of Maine, Orono, ME (United States)

2017-08-15

Volume II of the Final Report for the DeepCwind Consortium National Research Program funded by US Department of Energy Award Number: DE-EE0003278.001 summarizes the design, construction, deployment, testing, numerical model validation, retrieval, and post-deployment inspection of the VolturnUS 1:8-scale floating wind turbine prototype deployed off Castine, Maine on June 2nd, 2013. The 1:8 scale VolturnUS design served as a de-risking exercise for a commercial multi-MW VolturnUS design. The American Bureau of Shipping Guide for Building and Classing Floating Offshore Wind Turbine Installations was used to design the prototype. The same analysis methods, design methods, construction techniques, deployment methods, mooring, and anchoring planned for full-scale were used. A commercial 20kW grid-connected turbine was used and was the first offshore wind turbine in the US.

Wind Energy Facilities

Energy Technology Data Exchange (ETDEWEB)

Laurie, Carol

2017-02-01

This book takes readers inside the places where daily discoveries shape the next generation of wind power systems. Energy Department laboratory facilities span the United States and offer wind research capabilities to meet industry needs. The facilities described in this book make it possible for industry players to increase reliability, improve efficiency, and reduce the cost of wind energy -- one discovery at a time. Whether you require blade testing or resource characterization, grid integration or high-performance computing, Department of Energy laboratory facilities offer a variety of capabilities to meet your wind research needs.

Testing and comparison of lidars for profile and turbulence measurements in wind energy

International Nuclear Information System (INIS)

Courtney, M; Wagner, R; Lindeloew, P

2008-01-01

Lidar profilers are beginning to gain a foothold in wind energy. Both of the currently available commercially systems have been extensively tested at the Hovsore facility in Denmark and valuable insights have been gained. The extensively instrumented facility will be described and some examples of the results given, illustrating the strength and weaknesses of the two contrasting profilers

Fatigue testing of a carbon fibre composite wind turbine blade with associated material characterisation

Energy Technology Data Exchange (ETDEWEB)

Lowe, G A; Richardson, D J [Univ. of the West of England, Faculty of Engineering, Bristol (United Kingdom)

1996-09-01

Within the EC project JOULE 2, the University of the West of England (UWE) tested a carbon fibre reinforced epoxy (CFRE) full scale wind turbine blade together with an associated material test coupon programme. All the work was closely linked with the manufacturer Polymarine BV of the Netherlands, who designed and manufactured the blade and provided test specimens, the UWE carried out the research into the validation of the design calculations together with a check of the strength and fatigue life of the blade. (au)

Wind tunnel tests with combined pitch and free-floating flap control: data-driven iterative feedforward controller tuning

Directory of Open Access Journals (Sweden)

S. T. Navalkar

2016-10-01

Full Text Available Wind turbine load alleviation has traditionally been addressed in the literature using either full-span pitch control, which has limited bandwidth, or trailing-edge flap control, which typically shows low control authority due to actuation constraints. This paper combines both methods and demonstrates the feasibility and advantages of such a combined control strategy on a scaled prototype in a series of wind tunnel tests. The pitchable blades of the test turbine are instrumented with free-floating flaps close to the tip, designed such that they aerodynamically magnify the low stroke of high-bandwidth actuators. The additional degree of freedom leads to aeroelastic coupling with the blade flexible modes. The inertia of the flaps was tuned such that instability occurs just beyond the operational envelope of the wind turbine; the system can however be stabilised using collocated closed-loop control. A feedforward controller is shown to be capable of significant reduction of the deterministic loads of the turbine. Iterative feedforward tuning, in combination with a stabilising feedback controller, is used to optimise the controller online in an automated manner, to maximise load reduction. Since the system is non-linear, the controller gains vary with wind speed; this paper also shows that iterative feedforward tuning is capable of generating the optimal gain schedule online.

Aggregated wind power plant models consisting of IEC wind turbine models

DEFF Research Database (Denmark)

Altin, Müfit; Göksu, Ömer; Hansen, Anca Daniela

2015-01-01

The common practice regarding the modelling of large generation components has been to make use of models representing the performance of the individual components with a required level of accuracy and details. Owing to the rapid increase of wind power plants comprising large number of wind...... turbines, parameters and models to represent each individual wind turbine in detail makes it necessary to develop aggregated wind power plant models considering the simulation time for power system stability studies. In this paper, aggregated wind power plant models consisting of the IEC 61400-27 variable...... speed wind turbine models (type 3 and type 4) with a power plant controller is presented. The performance of the detailed benchmark wind power plant model and the aggregated model are compared by means of simulations for the specified test cases. Consequently, the results are summarized and discussed...

Second-Generation Large Civil Tiltrotor 7- by 10-Foot Wind Tunnel Test Data Report

Science.gov (United States)

Theodore, Colin R.; Russell, Carl R.; Willink, Gina C.; Pete, Ashley E.; Adibi, Sierra A.; Ewert, Adam; Theuns, Lieselotte; Beierle, Connor

2016-01-01

An approximately 6-percent scale model of the NASA Second-Generation Large Civil Tiltrotor (LCTR2) Aircraft was tested in the U.S. Army 7- by 10-Foot Wind Tunnel at NASA Ames Research Center January 4 to April 19, 2012, and September 18 to November 1, 2013. The full model was tested, along with modified versions in order to determine the effects of the wing tip extensions and nacelles; the wing was also tested separately in the various configurations. In both cases, the wing and nacelles used were adopted from the U.S. Army High Efficiency Tilt Rotor (HETR) aircraft, in order to limit the cost of the experiment. The full airframe was tested in high-speed cruise and low-speed hover flight conditions, while the wing was tested only in cruise conditions, with Reynolds numbers ranging from 0 to 1.4 million. In all cases, the external scale system of the wind tunnel was used to collect data. Both models were mounted to the scale using two support struts attached underneath the wing; the full airframe model also used a third strut attached at the tail. The collected data provides insight into the performance of the preliminary design of the LCTR2 and will be used for computational fluid dynamics (CFD) validation and the development of flight dynamics simulation models.

Design, Fabrication, and Performance Test of a 100-W Helical-Blade Vertical-Axis Wind Turbine at Low Tip-Speed Ratio

Directory of Open Access Journals (Sweden)

Dowon Han

2018-06-01

Full Text Available A 100-W helical-blade vertical-axis wind turbine was designed, manufactured, and tested in a wind tunnel. A relatively low tip-speed ratio of 1.1 was targeted for usage in an urban environment at a rated wind speed of 9 m/s and a rotational speed of 170 rpm. The basic dimensions were determined through a momentum-based design method according to the IEC 61400-2 protocol. The power output was estimated by a mathematical model that takes into account the aerodynamic performance of the NACA0018 blade shape. The lift and drag of the blade with respect to the angle of attack during rotation were calculated using 2D computational fluid dynamics (CFD simulation to take into account stall region. The average power output calculated by the model was 108.34 W, which satisfies the target output of 100 W. The manufactured wind turbine was tested in a large closed-circuit wind tunnel, and the power outputs were measured for given wind speeds. At the design condition, the measured power output was 114.7 W, which is 5.9% higher than that of the mathematical model. This result validates the proposed design method and power estimation by the mathematical model.

Reliability assessment of Wind turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2015-01-01

Wind turbines can be considered as structures that are in between civil engineering structures and machines since they consist of structural components and many electrical and machine components together with a control system. Further, a wind turbine is not a one-of-a-kind structure...... but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...

Efficient preliminary floating offshore wind turbine design and testing methodologies and application to a concrete spar design

OpenAIRE

Matha, Denis; Sandner, Frank; Molins i Borrell, Climent; Campos Hortigüela, Alexis; Cheng, Po Wen

2015-01-01

The current key challenge in the floating offshore wind turbine industry and research is on designing economic floating systems that can compete with fixed-bottom offshore turbines in terms of levelized cost of energy. The preliminary platform design, as well as early experimental design assessments, are critical elements in the overall design process. In this contribution, a brief review of current floating offshore wind turbine platform pre-design and scaled testing methodologies is provide...

Heat-flux gage measurements on a flat plate at a Mach number of 4.6 in the VSD high speed wind tunnel, a feasibility test (LA28). [wind tunnel tests of measuring instruments for boundary layer flow

Science.gov (United States)

1975-01-01

The feasibility of employing thin-film heat-flux gages was studied as a method of defining boundary layer characteristics at supersonic speeds in a high speed blowdown wind tunnel. Flow visualization techniques (using oil) were employed. Tabulated data (computer printouts), a test facility description, and photographs of test equipment are given.

Development, construction and testing of a vertical axis 200 kW wind turbine

Energy Technology Data Exchange (ETDEWEB)

1974-12-20

It is proposed to design and develop a large vertical axis wind turbine that will generate economically 200 kilowatts of power at a wind speed of about 30 miles per hour. The scope of this proposal is to carry out studies, build, erect and test an electrical power generation plant that will feed into existing power grids. Preliminary technical studies indicate that the power of the turbine increases with the third power of the the wind speed. The rotor power loading should be as high as the prevailing winds allow; thus it would always be advisable to let the rotor run at as high an rpm as the economics will allow. For turbines up to about 100 ft in diameter, an extruded blade seems to be the best solution for economic rotor design. A 300 ft/s runaway tip speed seems to be acceptable as an rpm limit. Structurally, it is advantageous to increase the blade airfoil section to 18%. The proposed program has a very high probability of success in that each element of the total system involves a very low technical risk. The manufacturing methods rely on existing technology, and preliminary research indicates that readily available commercial materials can be used. There will be no involvement with highly stressed, fatigue-sensitive components. The total unit energy cost will be about fifty percent less for the proposed 90 ft. turbine than for the 15 ft. turbine produced for the National Research Council. 8 figs., 12 tabs.

Wind Turbine Blade Nondestructive Testing with a Transportable Radiography System

Directory of Open Access Journals (Sweden)

J. G. Fantidis

2011-01-01

Full Text Available Wind turbines are becoming widely used as they are an environmentally friendly way for energy production without emissions; however, they are exposed to a corrosive environment. In addition, as wind turbines typically are the tallest structures in the surrounding area of a wind farm, it is expected that they will attract direct lightning strikes several times during their operating life. The purpose of this paper is to show that the radiography with a transportable unit is a solution to find defects in the wind turbine blade and reduce the cost of inspection. A transportable neutron radiography system, incorporating an Sb–Be source, has been simulated using the MCNPX code. The simulated system has a wide range of radiography parameters.

Design, Analysis, Hybrid Testing and Orientation Control of a Floating Platform with Counter-Rotating Vertical-Axis Wind Turbines

Science.gov (United States)

Kanner, Samuel Adam Chinman

The design and operation of two counter-rotating vertical-axis wind turbines on a floating, semi-submersible platform is studied. The technology, called the Multiple Integrated and Synchronized Turbines (MIST) platform has the potential to reduce the cost of offshore wind energy per unit of installed capacity. Attached to the platform are closely-spaced, counter-rotating turbines, which can achieve a higher power density per planform area because of synergistic interaction effects. The purpose of the research is to control the orientation of the platform and rotational speeds of the turbines by modifying the energy absorbed by each of the generators of the turbines. To analyze the various aspects of the platform and wind turbines, the analysis is drawn from the fields of hydrodynamics, electromagnetics, aerodynamics and control theory. To study the hydrodynamics of the floating platform in incident monochromatic waves, potential theory is utilized, taking into account the slow-drift yaw motion of the platform. Steady, second-order moments that are spatially dependent (i.e., dependent on the platform's yaw orientation relative to the incident waves) are given special attention since there are no natural restoring yaw moment. The aerodynamics of the counter-rotating turbines are studied in collaboration with researchers at the UC Berkeley Mathematics Department using a high-order, implicit, large-eddy simulation. An element flipping technique is utilized to extend the method to a domain with counter-rotating turbines and the effects from the closely-spaced turbines is compared with existing experimental data. Hybrid testing techniques on a model platform are utilized to prove the controllability of the platform in lieu of a wind-wave tank. A 1:82 model-scale floating platform is fabricated and tested at the UC Berkeley Physical-Model Testing Facility. The vertical-axis wind turbines are simulated by spinning, controllable actuators that can be updated in real-time of

Report on a wind power development field test project (detailed wind condition investigation) in the city of Choshi; Choshishi ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-11-01

This paper describes observation on the annual wind condition at the Yokka-ichibadai in the city of Choshi. The average wind velocities were 4.7 and 3.8 m/s at the ground height of 20 and 10 meters, respectively, not having reached the NEDO's criterion values 5.6 and 5.0 m/s. The annual wind direction emergence rate on the wind axis was 70%, meeting the criterion value of 60% or higher, and the wind direction is stable. The exponent for the vertical wind velocity distribution was 3.3, which is similar to that in the urban area. Disturbance in the wind condition was 0.18, meeting the criterion value of 0.30 or lower. The maximum momentary wind velocity was 31.9 m/s, which is well below the criterion of 60 m/s presenting no problem as a wind mill construction site. The wind energy density was 94 W/m{sup 2}, being only 63% of the criterion value, when all the azimuths were used as the object. The result of the investigation is that the average wind velocity is low and the wind energy density is also low. However, if the size of wind mill to be introduced is set to the class B (300 kW), it is possible to attain an annual operation rate of 58%, an annual energy acquisition amount of 515 MWh, and a facility utilization rate of 19.6%. If set to the class C (750 kW), an operation rate of 78%, an annual energy acquisition of 1296 MWh, and a facility utilization rate of 19.7% can be obtained, meeting the criterion value. (NEDO)

Wake losses optimization of offshore wind farms with moveable floating wind turbines

International Nuclear Information System (INIS)

Rodrigues, S.F.; Teixeira Pinto, R.; Soleimanzadeh, M.; Bosman, Peter A.N.; Bauer, P.

2015-01-01

Highlights: • We present a layout optimization framework for wind farms with moveable turbines. • Using moveable wind turbines in optimized layouts maximizes energy production. • Turbine and wind farm designers should cooperate to optimize offshore wind projects. - Abstract: In the future, floating wind turbines could be used to harvest energy in deep offshore areas where higher wind mean speeds are observed. Currently, several floating turbine concepts are being designed and tested in small scale projects; in particular, one concept allows the turbine to move after installation. This article presents a novel layout optimization framework for wind farms composed of moveable floating turbines. The proposed framework uses an evolutionary optimization strategy in a nested configuration which simultaneously optimizes the anchoring locations and the wind turbine position within the mooring lines for each individual wind direction. The results show that maximum energy production is obtained when moveable wind turbines are deployed in an optimized layout. In conclusion, the framework represents a new design optimization tool for future offshore wind farms composed of moveable floating turbines

Second wind in the offshore wind industry

International Nuclear Information System (INIS)

Philippe, Edouard; Neyme, Eric; Deboos, Christophe; Villageois, Jean-Remy; Gouverneur, Philippe; Gerard, Bernard; Fournier, Eric; Petrus, Raymond; Lemarquis, David; Dener, Marc; Bivaud, Jean-Pierre; Lemaire, Etienne; Nielsen, Steffen; Lafon, Xavier; Lagandre, Pierre; Nadai, Alain; Pinot de Villechenon, Edouard; Westhues, Markus; Herpers, Frederick; Bisiaux, Christophe; Sperlich, Miriam; Bales, Vincent; Vandenbroeck, Jan; His, Stephane; Derrey, Thierry; Barakat, Georges; Dakyo, Brayima; Carme, Laurent; Petit, Frederic; Ytournel, Sophie; Westhues, Markus; Diller, Armin; Premont, Antoine de; Ruer, Jacques; Lanoe, Frederic; Declercq, Jan; Holmager, Morten; Fidelin, Daniel; Guillet, Jerome; Dudziak, Gregory; Lapierre, Anne; Couturier, Ludovic; Audineau, Jean-Pierre; Rouaix, Eric; De Roeck, Yann-Herve; Quesnel, Louis; Duguet, Benjamin

2011-06-01

After several keynote addresses, this publication contains contributions and Power Point presentations proposed during this conference on the development of offshore wind energy. The successive sessions addressed the following issues: the offshore mass production of electricity (examples of Denmark and Belgium, laying and protecting offshore cables), the space, economic and environmental planning (the Danish experience, the role of the Coastal area integrated management, importance of the public debate, so on), the logistics of port infrastructures (simulation tools, example of Bremerhaven, issues related to project management), innovation at the core of industrial strategies (high power wind turbines, the 6 MW Alstom turbine, chain value and innovation in offshore wind energy, the Vertiwing innovating project of a floating wind turbine, a bench test in Charleston, foundations, gravity base structures, the British experience, the Danish experience), the economic and organisational conditions for development, the validation and certification of technologies

Full-scale wind-tunnel tests of high-lift system modifications on a carrier based fighter aircraft

Science.gov (United States)

Meyn, Larry A.; Zell, Peter T.; Hagan, John L.; Schoch, David

1993-01-01

Modifications to the high-lift system of a full-scale F/A-I8A were tested in the 80- by 120-Foot Wind Tunnel of the National Full-Scale Aerodynamics Complex at the NASA Ames Research Center in Moffett Field, California. The objective was to measure the effect of simple modifications on the aerodynamic performance of the high-lift system. The modifications included the placement of a straight fairing in the shroud cove above the trailing-edge flap and the addition of seals to prevent air leakage through the hinge lines of the leading-edge flap, the trailing-edge shroud, and the wing fold. The test was carried out on an actual F/A-18A with it's flaps deployed in the landing approach configuration. The angle of attack ranged from 0 to 16 degrees and the wind speed was 100 knots. At an angle of attack of 8 degrees, the trimmed lift coefficient was improved by 0.09 with all wing seals in place. This corresponds to a reduction in the approach speed for the F/A-I8A of about 5 knots. The seal along the wing fold hinge, a feature present on many naval aircraft, provided one third of the total increment in trimmed lift. A comparison of the full-scale wind-tunnel results with those obtained from flight test is also presented.

Wall correction model for wind tunnels with open test section

DEFF Research Database (Denmark)

Sørensen, Jens Nørkær; Shen, Wen Zhong; Mikkelsen, Robert Flemming

2006-01-01

In the paper we present a correction model for wall interference on rotors of wind turbines or propellers in wind tunnels. The model, which is based on a one-dimensional momentum approach, is validated against results from CFD computations using a generalized actuator disc principle. In the model...... good agreement with the CFD computations, demonstrating that one-dimensional momentum theory is a reliable way of predicting corrections for wall interference in wind tunnels with closed as well as open cross sections....

Propulsion and airframe aerodynamic interactions of supersonic V/STOL configurations. Volume 2: Wind tunnel test force and moment data report

Science.gov (United States)

Zilz, D. E.

1985-01-01

A wind tunnel model of a supersonic V/STOL fighter configuration has been tested to measure the aerodynamic interaction effects which can result from geometrically close-coupled propulsion system/airframe components. The approach was to configure the model to represent two different test techniques. One was a conventional test technique composed of two test modes. In the Flow-Through mode, absolute configuration aerodynamics are measured, including inlet/airframe interactions. In the Jet-Effects mode, incremental nozzle/airframe interactions are measured. The other test technique is a propulsion simulator approach, where a sub-scale, externally powered engine is mounted in the model. This allows proper measurement of inlet/airframe and nozzle/airframe interactions simultaneously. This is Volume 2 of 2: Wind Tunnel Test Force and Moment Data Report.

Site calibration for the wind turbine performance evaluation

International Nuclear Information System (INIS)

Nam, Yoon Su; Yoo, Neung Soo; Lee, Jung Wan

2004-01-01

The accurate wind speed information at the hub height of a wind turbine is very essential to the exact estimation of the wind turbine power performance testing. Several method on the site calibration, which is a technique to estimate the wind speed at the wind turbine's hub height based on the measured wind data using a reference meteorological mast, are introduced. A site calibration result and the wind resource assessment for the TaeKwanRyung test site are presented using three-month wind data from a reference meteorological mast and the other mast temporarily installed at the site of wind turbine. Besides, an analysis on the uncertainty allocation for the wind speed correction using site calibration is performed

Report on field test project for wind power development at Onejime Athletic Park. Detailed wind characteristics survey; Onejime Undo Koen ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A detailed wind characteristics survey was conducted to study the feasibility of a wind power generation system for Onejime Athletic Park, Kimotsugu-gun, Kagoshima Prefecture. Observation instruments were installed at a wasteland beside the park and, in the period October 1, 1998, through September 30, 1999, data were collected at a point 20m above ground, such as the average wind speed and direction, wind velocity standard deviation, and the maximum instantaneous wind velocity. The data were analyzed, and findings were obtained, as mentioned below. The wind axis along which the wind direction occurrence rate was the highest ran WNW-ESE at an occurrence rate of 65.8%. Turbulence intensity was 0.23 at wind speeds of 2m/s and more, the maximum instantaneous wind velocity was 40m/s, all these fully satisfying the evaluation levels set forth by NEDO (New Energy and Industrial Technology Development Organization). On the other hand, the average wind speed was 3.48m/s and wind energy density was 69W/m{sup 2}, these failing to satisfy the levels indicated by NEDO. Studies were made on the assumption that 150, 300, and 750kW-class wind turbines would be introduced, and then it was found that their annual operating factors and facility availability rates both failed to meet the NEDO standards concerned and that therefore the site in question was not fit for wind power generation. (NEDO)

Modeling wind speed and wind power distributions in Rwanda

Energy Technology Data Exchange (ETDEWEB)

Safari, Bonfils [Department of Physics, National University of Rwanda, P.O. Box 117, Huye District, South Province (Rwanda)

2011-02-15

Utilization of wind energy as an alternative energy source may offer many environmental and economical advantages compared to fossil fuels based energy sources polluting the lower layer atmosphere. Wind energy as other forms of alternative energy may offer the promise of meeting energy demand in the direct, grid connected modes as well as stand alone and remote applications. Wind speed is the most significant parameter of the wind energy. Hence, an accurate determination of probability distribution of wind speed values is very important in estimating wind speed energy potential over a region. In the present study, parameters of five probability density distribution functions such as Weibull, Rayleigh, lognormal, normal and gamma were calculated in the light of long term hourly observed data at four meteorological stations in Rwanda for the period of the year with fairly useful wind energy potential (monthly hourly mean wind speed anti v{>=}2 m s{sup -1}). In order to select good fitting probability density distribution functions, graphical comparisons to the empirical distributions were made. In addition, RMSE and MBE have been computed for each distribution and magnitudes of errors were compared. Residuals of theoretical distributions were visually analyzed graphically. Finally, a selection of three good fitting distributions to the empirical distribution of wind speed measured data was performed with the aid of a {chi}{sup 2} goodness-of-fit test for each station. (author)

DEVIATION OF STELLAR ORBITS FROM TEST PARTICLE TRAJECTORIES AROUND SGr A* DUE TO TIDES AND WINDS

International Nuclear Information System (INIS)

Psaltis, Dimitrios; Li, Gongjie; Loeb, Abraham

2013-01-01

Monitoring the orbits of stars around Sgr A* offers the possibility of detecting the precession of their orbital planes due to frame dragging, of measuring the spin and quadrupole moment of the black hole, and of testing the no-hair theorem. Here we investigate whether the deviations of stellar orbits from test-particle trajectories due to wind mass loss and tidal dissipation of the orbital energy compromise such measurements. We find that the effects of stellar winds are, in general, negligible. On the other hand, for the most eccentric orbits (e > 0.96) for which an optical interferometer, such as GRAVITY, will detect orbital plane precession due to frame dragging, the tidal dissipation of orbital energy occurs at timescales comparable to the timescale of precession due to the quadrupole moment of the black hole. As a result, this non-conservative effect is a potential source of systematic uncertainty in testing the no-hair theorem with stellar orbits

DEVIATION OF STELLAR ORBITS FROM TEST PARTICLE TRAJECTORIES AROUND SGr A* DUE TO TIDES AND WINDS

Energy Technology Data Exchange (ETDEWEB)

Psaltis, Dimitrios [Astronomy Department, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Li, Gongjie; Loeb, Abraham, E-mail: dpsaltis@email.arizona.edu, E-mail: gli@cfa.harvard.edu, E-mail: aloeb@cfa.harvard.edu [Institute for Theory and Computation, Harvard-Smithsonian CfA, 60 Garden Street, Cambridge, MA (United States)

2013-11-01

Monitoring the orbits of stars around Sgr A* offers the possibility of detecting the precession of their orbital planes due to frame dragging, of measuring the spin and quadrupole moment of the black hole, and of testing the no-hair theorem. Here we investigate whether the deviations of stellar orbits from test-particle trajectories due to wind mass loss and tidal dissipation of the orbital energy compromise such measurements. We find that the effects of stellar winds are, in general, negligible. On the other hand, for the most eccentric orbits (e > 0.96) for which an optical interferometer, such as GRAVITY, will detect orbital plane precession due to frame dragging, the tidal dissipation of orbital energy occurs at timescales comparable to the timescale of precession due to the quadrupole moment of the black hole. As a result, this non-conservative effect is a potential source of systematic uncertainty in testing the no-hair theorem with stellar orbits.

Multi-component wind measurements of wind turbine wakes performed with three LiDARs

Science.gov (United States)

Iungo, G. V.; Wu, Y.-T.; Porté-Agel, F.

2012-04-01

Field measurements of the wake flow produced from the interaction between atmospheric boundary layer and a wind turbine are performed with three wind LiDARs. The tested wind turbine is a 2 MW Enercon E-70 located in Collonges, Switzerland. First, accuracy of mean values and frequency resolution of the wind measurements are surveyed as a function of the number of laser rays emitted for each measurement. Indeed, measurements performed with one single ray allow maximizing sampling frequency, thus characterizing wake turbulence. On the other hand, if the number of emitted rays is increased accuracy of mean wind is increased due to the longer sampling period. Subsequently, two-dimensional measurements with a single LiDAR are carried out over vertical sections of the wind turbine wake and mean wake flow is obtained by averaging 2D measurements consecutively performed. The high spatial resolution of the used LiDAR allows characterizing in details velocity defect present in the central part of the wake and its downstream recovery. Single LiDAR measurements are also performed by staring the laser beam at fixed directions for a sampling period of about ten minutes and maximizing the sampling frequency in order to characterize wake turbulence. From these tests wind fluctuation peaks are detected in the wind turbine wake at blade top-tip height for different downstream locations. The magnitude of these turbulence peaks is generally reduced by moving downstream. This increased turbulence level at blade top-tip height observed for a real wind turbine has been already detected from previous wind tunnel tests and Large Eddy simulations, thus confirming the presence of a source of dangerous fatigue loads for following wind turbines within a wind farm. Furthermore, the proper characterization of wind fluctuations through LiDAR measurements is proved by the detection of the inertial subrange from spectral analysis of these velocity signals. Finally, simultaneous measurements with two

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

Science.gov (United States)

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

2015-02-28

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

Overload prevention in model supports for wind tunnel model testing

Directory of Open Access Journals (Sweden)

Anton IVANOVICI

2015-09-01

Full Text Available Preventing overloads in wind tunnel model supports is crucial to the integrity of the tested system. Results can only be interpreted as valid if the model support, conventionally called a sting remains sufficiently rigid during testing. Modeling and preliminary calculation can only give an estimate of the sting’s behavior under known forces and moments but sometimes unpredictable, aerodynamically caused model behavior can cause large transient overloads that cannot be taken into account at the sting design phase. To ensure model integrity and data validity an analog fast protection circuit was designed and tested. A post-factum analysis was carried out to optimize the overload detection and a short discussion on aeroelastic phenomena is included to show why such a detector has to be very fast. The last refinement of the concept consists in a fast detector coupled with a slightly slower one to differentiate between transient overloads that decay in time and those that are the result of aeroelastic unwanted phenomena. The decision to stop or continue the test is therefore conservatively taken preserving data and model integrity while allowing normal startup loads and transients to manifest.

An innovative medium speed wind turbine rotor blade design for low wind regime (electrical power generation)

International Nuclear Information System (INIS)

Abas Abd Wahab; Chong Wen Tong

2001-01-01

This paper describes the preliminary study of a small-scale wind turbine rotor blade (a low wind speed region turbine). A new wind turbine rotor blade (AE2 blade) for stand alone system has been conceptualized, designed, constructed and tested. The system is a reduced size prototype (half-scaled) to develop an efficient (adapted to Malaysian wind conditions)and cost effective wind energy conversion system (WECS) with local design and production technique. The blades were constructed from aluminium sheet with metal blending technique. The layout and design of rotor blade, its innovative features and test results are presented. Results from indoor test showed that the advantages of AE2 blade in low speed, with the potential of further improvements. The best rotor efficiency, C P attained with simple AE2 blades rotor (number of blade = 3) was 37.3% (Betz efficiency = 63%) at tip speed ratio (TSR) = 3.6. From the fabrication works and indoor testing, the AE2 blade rotor has demonstrated its structural integrity (ease of assembly and transportation), simplicity, acceptable performance and low noise level. (Author)

Test and analysis results for two Synergy Power Corp. wind turbines

Energy Technology Data Exchange (ETDEWEB)

Davis, D.; Hansen, C. [Windward Engineering, L.C., Salt Lake City, UT (United States)

1996-12-31

The testing and modeling of small (rotor diameter 10.3 m and 12.8 m) wind turbines is the subject of this paper. The paper focuses primarily on the ADAMS computer model for dynamic analysis. The code calculates design loads, optimizes tilt configuration, and helps to interpret test results. A comparison of some of the modeling predictions is made to test data for validation purposes. The ADAMS model was found to accurately predict performance characteristics and loads for free-tilting turbines. ADAMS was found to be relatively successful in modeling the free tilt and variable rotors. The model also showed that tilting behavior is dependent on the restoring moment from the rotor aerodynamics as well as on surface aerodynamics. The effects of changes in air density on the power curve, load predictions, and analysis of emergency stops were also performed satisfactorily with the model. 15 figs.

Predicting Faults in Wind Turbines Using SCADA Data

DEFF Research Database (Denmark)

Borchersen, Anders Bech; Larsen, Jesper Abildgaard; Stoustrup, Jakob

2013-01-01

The cost of operation and maintenance of wind turbines is a significant part of the overall cost of wind turbines. To reduce this cost a method for enabling early fault detection is proposed and tested in this paper. The method is taking advantage of the fact that wind turbines in wind farms...... and tested on historical Supervisory Control And Data Acquisition (SCADA) data from nine operational turbines over a testing period of nine months. The performance of the fault detection is found to be acceptable based on the testing period. During the testing period several gear related services were...

Development and test of an axial flux type PM synchronous motor with liquid nitrogen cooled HTS armature windings

International Nuclear Information System (INIS)

Sugimoto, H; Morishita, T; Tsuda, T; Takeda, T; Togawa, H; Oota, T; Ohmatsu, K; Yoshida, S

2008-01-01

We developed an axial gap permanent magnet type superconducting synchronous motor cooled by liquid nitrogen (LN 2 ). The motor includes 8 poles and 6 armature windings. The armature windings are made from BSCCO wire operated at the temperature level between 66K∼70K. The design of the rated output is 400kW at 250rpm. Because HTS wires produce AC loss, there are few motors developed with a superconducting armature winding. In a large capacity motor, HTS windings need to be connected in parallel way. However, the parallel connection causes different current flowing to each HTS winding. To solve this problem, we connected a current distributor to the motor. As a result, not only the current difference can be suppressed, but also the current of each winding can be adjusted freely. The low frequency and less flux penetrating HTS wire because of current distributor contribute to low AC loss. This motor is an axial gap rotating-field one, the cooling parts are fixed. This directly leads to simple cooling system. The motor is also brushless. This paper presents the structure, the analysis of the motor and the tests

Wind loads on flat plate photovoltaic array fields

Science.gov (United States)

Miller, R. D.; Zimmerman, D. K.

1981-01-01

The results of an experimental analysis (boundary layer wind tunnel test) of the aerodynamic forces resulting from winds acting on flat plate photovoltaic arrays are presented. Local pressure coefficient distributions and normal force coefficients on the arrays are shown and compared to theoretical results. Parameters that were varied when determining the aerodynamic forces included tilt angle, array separation, ground clearance, protective wind barriers, and the effect of the wind velocity profile. Recommended design wind forces and pressures are presented, which envelop the test results for winds perpendicular to the array's longitudinal axis. This wind direction produces the maximum wind loads on the arrays except at the array edge where oblique winds produce larger edge pressure loads. The arrays located at the outer boundary of an array field have a protective influence on the interior arrays of the field. A significant decrease of the array wind loads were recorded in the wind tunnel test on array panels located behind a fence and/or interior to the array field compared to the arrays on the boundary and unprotected from the wind. The magnitude of this decrease was the same whether caused by a fence or upwind arrays.

Assessment of C-Type Darrieus Wind Turbine Under Low Wind Speed Condition

Science.gov (United States)

Misaran, M. S.; Rahman, Md. M.; Muzammil, W. K.; Ismail, M. A.

2017-07-01

Harvesting wind energy in in a low wind speed region is deem un-economical if not daunting task. Study shows that a minimum cut in speed of 3.5 m/s is required to extract a meaningful wind energy for electricity while a mean speed of 6 m/s is preferred. However, in Malaysia the mean speed is at 2 m/s with certain potential areas having 3 m/s mean speed. Thus, this work aims to develop a wind turbine that able to operate at lower cut-in speed and produce meaningful power for electricity generation. A C-type Darrieus blade is selected as it shows good potential to operate in arbitrary wind speed condition. The wind turbine is designed and fabricated in UMS labs while the performance of the wind turbine is evaluated in a simulated wind condition. Test result shows that the wind turbine started to rotate at 1 m/s compared to a NACA 0012 Darrieus turbine that started to rotate at 3 m/s. The performance of the turbine shows that it have good potential to be used in an intermittent arbitrary wind speed condition as well as low mean wind speed condition.

HNEI wind-hydrogen program

International Nuclear Information System (INIS)

Neill, D.; Holst, B.; Yu, C.; Huang, N.; Wei, J.

1990-01-01

This paper reports on wind powered hydrogen production which is promising for Hawaii because Hawaii's wind energy potential exceeds the state's current electrical energy requirements by more than twenty-fold. Wind energy costs are now approaching $0.06 to $0.08/kWh, and the U.S. Department of Energy has set a goal of $0.04/kWh. These conditions make wind power a good source for electrolytic production of hydrogen. HNEI's wind-hydrogen program, at the HNEI-Kahua Wind Energy Storage Test facility on the island of Hawaii, is developing energy storage and power electronic systems for intermittent wind and solar devices to provide firm power to the utility or to a stand-alone hybrid system. In mid 1990, the first wind-hydrogen production/storage/ generation system is scheduled for installation. HNEI's wind- hydrogen program will provide research, development, demonstration, and education on the great potential and benefits of hydrogen

FAST Model Calibration and Validation of the OC5-DeepCwind Floating Offshore Wind System Against Wave Tank Test Data

Energy Technology Data Exchange (ETDEWEB)

Wendt, Fabian F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Robertson, Amy N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jonkman, Jason [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-06-03

During the course of the Offshore Code Comparison Collaboration, Continued, with Correlation (OC5) project, which focused on the validation of numerical methods through comparison against tank test data, the authors created a numerical FAST model of the 1:50-scale DeepCwind semisubmersible system that was tested at the Maritime Research Institute Netherlands ocean basin in 2013. This paper discusses several model calibration studies that were conducted to identify model adjustments that improve the agreement between the numerical simulations and the experimental test data. These calibration studies cover wind-field-specific parameters (coherence, turbulence), hydrodynamic and aerodynamic modeling approaches, as well as rotor model (blade-pitch and blade-mass imbalances) and tower model (structural tower damping coefficient) adjustments. These calibration studies were conducted based on relatively simple calibration load cases (wave only/wind only). The agreement between the final FAST model and experimental measurements is then assessed based on more-complex combined wind and wave validation cases.

A methodology for the design and testing of atmospheric boundary layer models for wind energy applications

Directory of Open Access Journals (Sweden)

J. Sanz Rodrigo

2017-02-01

Full Text Available The GEWEX Atmospheric Boundary Layer Studies (GABLS 1, 2 and 3 are used to develop a methodology for the design and testing of Reynolds-averaged Navier–Stokes (RANS atmospheric boundary layer (ABL models for wind energy applications. The first two GABLS cases are based on idealized boundary conditions and are suitable for verification purposes by comparing with results from higher-fidelity models based on large-eddy simulation. Results from three single-column RANS models, of 1st, 1.5th and 2nd turbulence closure order, show high consistency in predicting the mean flow. The third GABLS case is suitable for the study of these ABL models under realistic forcing such that validation versus observations from the Cabauw meteorological tower are possible. The case consists on a diurnal cycle that leads to a nocturnal low-level jet and addresses fundamental questions related to the definition of the large-scale forcing, the interaction of the ABL with the surface and the evaluation of model results with observations. The simulations are evaluated in terms of surface-layer fluxes and wind energy quantities of interest: rotor equivalent wind speed, hub-height wind direction, wind speed shear and wind direction veer. The characterization of mesoscale forcing is based on spatially and temporally averaged momentum budget terms from Weather Research and Forecasting (WRF simulations. These mesoscale tendencies are used to drive single-column models, which were verified previously in the first two GABLS cases, to first demonstrate that they can produce similar wind profile characteristics to the WRF simulations even though the physics are more simplified. The added value of incorporating different forcing mechanisms into microscale models is quantified by systematically removing forcing terms in the momentum and heat equations. This mesoscale-to-microscale modeling approach is affected, to a large extent, by the input uncertainties of the mesoscale

Probabilistic Design of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Toft, H.S.

2010-01-01

Probabilistic design of wind turbines requires definition of the structural elements to be included in the probabilistic basis: e.g., blades, tower, foundation; identification of important failure modes; careful stochastic modeling of the uncertain parameters; recommendations for target reliability....... It is described how uncertainties in wind turbine design related to computational models, statistical data from test specimens, results from a few full-scale tests and from prototype wind turbines can be accounted for using the Maximum Likelihood Method and a Bayesian approach. Assessment of the optimal...... reliability level by cost-benefit optimization is illustrated by an offshore wind turbine example. Uncertainty modeling is illustrated by an example where physical, statistical and model uncertainties are estimated....

WindScanner.eu - a new remote sensing research infrastructure for on- and offshore wind energy

Energy Technology Data Exchange (ETDEWEB)

Mikkelsen, Torben; Knudsen, Soeren; Sjoeholm, M.; Angeloua, N.; Tegtmeier, A. [Technical Univ. og Denmark. DTU Wind Energy, DTU Risoe Campus, Roskilde (Denmark)

2012-07-01

A new remote sensing based research infrastructure for atmospheric boundary-layer wind and turbulence measurements named WindScanner have during the past three years been in its early phase of development at DTU Wind Energy in Denmark. During the forthcoming three years the technology will be disseminated throughout Europe to pilot European wind energy research centers. The new research infrastructure will become an open source infrastructure that also invites collaboration with wind energy related atmospheric scientists and wind energy industry overseas. Recent achievements with 3D WindScanners and spin-off innovation activity are described. The Danish WindScanner.dk research facility is build from new and fast-scanning remote sensing equipment spurred from achievements within fiber optics and telecommunication technologies. At the same time the wind energy society has demanded excessive 3D wind flow and ever taller wind profile measurements for the wind energy resource assessment studies on- and off shore of the future. Today, hub heights on +5 MW wind turbines exceed the 100 m mark. At the Danish DTU test site Oesterild testing is ongoing with a Siemens turbine with hub height 120 meters and a rotor diameter of 154 meters; hence its blade tips reaches almost 200 meters into the sky. The wind speed profiles over the rotor planes are consequently no longer representatively measured by a single cup anemometer at hub height from a nearby met-mast; power curve assessment as well as turbine control call for multi-height multi point measurement strategies of wind speed and wind shear within the turbines entire rotor plane. The development of our new remote sensing-based WindScanner.dk facility as well as the first measurement results obtained to date are here presented, including a first wind lidar measurement of turbulence in complex terrain within an internal boundary layer developing behind an escarpment. Also measurements of wind speed and direction profiles

Early wind engineering experiments in Denmark

DEFF Research Database (Denmark)

Larose, Guy; Franck, Niels

1997-01-01

A review of works by Danish wind engineers is presented to commemorate the 100th year anniversary of the first wind tunnel experiments. Pioneer tests by Irminger and Nøkkentved in "artificial" wind on scaled models are described. The early experiments aimed at measuring the surface pressure......" that governs today´s wind engineering practice and gave birth to the boundary layer wind tunnel....

Fluoro-Jade and TUNEL staining as useful tools to identify ischemic brain damage following moderate extradural compression of sensorimotor cortex.

Science.gov (United States)

Kundrotiene, Jurgita; Wägner, Anna; Liljequist, Sture

2004-01-01

Cerebral ischemia was produced by moderate compression for 30 min of a specific brain area in the sensorimotor cortex of Sprague-Dawley rats. On day 1, that is 24 h after the transient sensorimotor compression, ischemia-exposed animals displayed a marked focal neurological deficit documented as impaired beam walking performance. This functional disturbance was mainly due to contralateral fore- and hind-limb paresis. As assessed by daily beam walking tests it was shown that there was a spontaneous recovery of motor functions over a period of five to seven days after the ischemic event. Using histopathological analysis (Nissl staining) we have previously reported that the present experimental paradigm does not produce pannecrosis (tissue cavitation) despite the highly reproducible focal neurological deficit. We now show how staining with fluorescent markers for neuronal death, that is Fluoro-Jade and TUNEL, respectively, identifies regional patterns of selective neuronal death. These observations add further support to the working hypothesis that the brain damage caused by cortical compression-induced ischemia consists of scattered, degenerating neurons in specific brain regions. Postsurgical administration of the AMPA receptor specific antagonist, LY326325 (30 mg/kg; i.p., 70 min after compression), not only improved beam walking performance on day 1 to 3, respectively but also significantly reduced the number of Fluoro-Jade stained neurons on day 5. These results suggest that enhanced AMPA/glutamate receptor activity is at least partially responsible for the ischemia-produced brain damage detected by the fluorescent marker Fluoro-Jade.

IEA Wind Task 32: Wind lidar identifying and mitigating barriers to the adoption of wind lidar

DEFF Research Database (Denmark)

Clifton, Andrew; Clive, Peter; Gottschall, Julia

2018-01-01

IEA Wind Task 32 exists to identify and mitigate barriers to the adoption of lidar for wind energy applications. It leverages ongoing international research and development activities in academia and industry to investigate site assessment, power performance testing, controls and loads, and complex...... flows. Since its initiation in 2011, Task 32 has been responsible for several recommended practices and expert reports that have contributed to the adoption of ground-based, nacelle-based, and floating lidar by the wind industry. Future challenges include the development of lidar uncertainty models......, best practices for data management, and developing community-based tools for data analysis, planning of lidar measurements and lidar configuration. This paper describes the barriers that Task 32 identified to the deployment of wind lidar in each of these application areas, and the steps that have been...

Current limiting characteristics of transformer type SFCL with coupled secondary windings according to its winding direction

Energy Technology Data Exchange (ETDEWEB)

Lim, Sung Hun [Dept. of Electrical Engineering, Soongsil University, Seoul (Korea, Republic of); Han, Tae Hee [Dept. of Aero Materials Engineering, Jungwon University, Goesan (Korea, Republic of)

2017-06-15

In this paper, the current limiting characteristics of the transformer type superconducting fault current limiter (SFCL) with the two coupled secondary windings due to its winding direction were analyzed. To analyze the dependence of transient fault current limiting characteristics on the winding direction of the additional secondary winding, the fault current limiting tests of the SFCL with an additional secondary winding, wound as subtractive polarity winding and additive polarity winding, were carried out. The time interval of quench occurrence between two superconducting elements comprising the transformer type SFCL with the additional secondary winding was confirmed to be affected by the winding direction of the additional secondary winding. In case of the subtractive polarity winding of the additional secondary winding, the time interval of the quench occurrence in two superconducting elements was shorter than the case of the additive polarity winding.

Current limiting characteristics of transformer type SFCL with coupled secondary windings according to its winding direction

International Nuclear Information System (INIS)

Lim, Sung Hun; Han, Tae Hee

2017-01-01

In this paper, the current limiting characteristics of the transformer type superconducting fault current limiter (SFCL) with the two coupled secondary windings due to its winding direction were analyzed. To analyze the dependence of transient fault current limiting characteristics on the winding direction of the additional secondary winding, the fault current limiting tests of the SFCL with an additional secondary winding, wound as subtractive polarity winding and additive polarity winding, were carried out. The time interval of quench occurrence between two superconducting elements comprising the transformer type SFCL with the additional secondary winding was confirmed to be affected by the winding direction of the additional secondary winding. In case of the subtractive polarity winding of the additional secondary winding, the time interval of the quench occurrence in two superconducting elements was shorter than the case of the additive polarity winding

Reliability assessment of wind farm-connected grids using Monte-Carlo testing

Energy Technology Data Exchange (ETDEWEB)

Belanger, Jean; Dufour, Christian [Opal-RT Technologies Inc., Montreal, QC (Canada); Paquin, Jean-Nicolas [BBA Inc., Mont-Saint-Hilaire, QC (Canada)

2010-07-01

The future of the power grid lies in large scale integration of distributed generation devices with the utility system, at either a medium- or low-voltage level. These new distribued generation technologies can offer benefits and opportunities to manufacturers and utilities in need of supplementary energy sources. However, a large increase in the number of distributed generation interconnections may potentially cause a number of technical concerns relating to the operation of the system in question. Because existing distribution networks were not originally designed to include complex distributed power-electronic systems, detailed testing of existing and future protection and control devices is necessary. The growing use of photovoltaic devices, wind turbines and other complex power electronic systems is changing the nature of distribution systems. The performance and stresses on wind farm and microgrid components will therefore depend on control and protection system reaction. In fact, this new generation of intelligent microgrids is becoming as complex as sophisticated high-voltage AC/DC transmission systems. This paper describes how the Monte Carlo simulation technique and parallel simulators can be used to evaluate worst-case stresses for different fault and operating conditions. (orig.)

Wall Correction Model for Wind Tunnels with Open Test Section

DEFF Research Database (Denmark)

Sørensen, Jens Nørkær; Shen, Wen Zhong; Mikkelsen, Robert Flemming

2004-01-01

, the corrections from the model are in very good agreement with the CFD computaions, demonstrating that one-dimensional momentum theory is a reliable way of predicting corrections for wall interference in wind tunnels with closed as well as open cross sections. Keywords: Wind tunnel correction, momentum theory...

Wind turbine blades for harnessing energy from Malaysian low speed wind - manufacturing technique

International Nuclear Information System (INIS)

Abas Abd Wahab; Azmin Shakrine

2000-01-01

Blades for wind turbine to harness energy in the Malaysia low speed winds have been designed. During wind tunnel testing, wind turbine model using this type of blades has cut in speed of 1.5 m/s and turned at 450 rpm at 4 m/s wind. The blades, due to their critical dimensions of 1.2 m length, 5 cm thickness, tapered and 15 degree twist, were difficult to produce especially in large number. Several production methods have been studied but for economical mass production, fibreglass blades using CNC cutting mould were chosen. The blade and mould designs and the manufacturing processes are briefly outlined in this paper. (Author)

Wind Data Analysis and Wind Flow Simulation Over Large Areas

Directory of Open Access Journals (Sweden)

Terziev Angel

2014-03-01

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

Analysis of technological innovation in Danish wind turbine industry - including the Test Station for Windturbines dual roll as research institution and certification authority

International Nuclear Information System (INIS)

Dannemand Andersen, P.

1993-01-01

The overall aim of this thesis is to examine the interactions between the Danish wind turbine industry and the Test Station for Wind Turbines. Because these interactions are concerning technological innovation, it follows that the innovation processes within the enterprises must be analyzed and modelled. The study is carried out as an iterative model-developing process using case study methods. The findings from some less structured interviews are discussed with literature and forms a basis for models and new interviews. The thesis is based on interviews with 20 R and D engineers in the Danish wind turbine industry, 7 engineers at The Test Station and 7 people involved in wind power abroad (American and British). The theoretical frame for this thesis is sociology/organizational theory and industrial engineering. The thesis consists of five main sections, dealing with technology and knowledge, innovation processes, organizational culture, innovation and interaction between the Test Station's research activities and the companies' innovation processes, and finally interaction through the Test Stations certification activity. First a taxonomy for technology and knowledge is established in order to clarify what kind of technology the interactions are all about, and what kind of knowledge is transferred during the interactions. This part of the thesis also contains an analysis of the patents drawn by the Danish wind turbine industry. The analysis shows that the Danish wind turbine industry do not use patents. Instead the nature of the technology and the speed of innovation are used to protect the industry's knowledge. (EG) (192 refs.)

Baseline investigations of bats and birds at Wind Turbine Test Centre Østerild

DEFF Research Database (Denmark)

The Department of Bioscience, Aarhus University was commissioned by the Danish Nature Agency to undertake a bat and bird monitoring programme prior to the construction of a national test centre for wind turbines near Østerild in Thy, Denmark. The occurrence and activity level of bats in Østerild...... Plantation and the vicinity were monitored in summer and autumn 2011. Bats were recorded on 57-100% of surveyed nights at individual wind turbine sites, ponds and lakes. A total of seven species were recorded. Pond bats were recorded at all sites and throughout the survey period in the plantation. Whooper...... swan, taiga bean goose, pink-footed goose and common crane were included as focal species in the ornithological investigations. In addition, species specific data on all bird species occurring regularly in the study area were collected. On the basis of a preliminary assessment of collision risk...

Soil erosion rates caused by wind and saltating sand stresses in a wind tunnel

International Nuclear Information System (INIS)

Ligotke, M.W.

1993-02-01

Wind erosion tests were performed in a wind tunnel in support of the development of long-term protective barriers to cap stabilized waste sites at the Hanford Site. Controlled wind and saltating sand erosive stresses were applied to physical models of barrier surface layers to simulate worst-case eolian erosive stresses. The goal of these tests was to provide information useful to the design and evaluation of the surface layer composition of an arid-region waste site barrier concept that incorporates a deep fine-soil reservoir. A surface layer composition is needed that will form an armor resistant to eolian erosion during periods of extreme dry climatic conditions, especially when such conditions result in the elimination or reduction of vegetation by water deprivation or wildfire. Because of the life span required of Hanford waste barriers, it is important that additional work follow these wind tunnel studies. A modeling effort is planned to aid the interpretation of test results with respect to the suitability of pea gravel to protect the finite-soil reservoir during long periods of climatic stress. It is additionally recommended that wind tunnel tests be continued and field data be obtained at prototype or actual barrier sites. Results wig contribute to barrier design efforts and provide confidence in the design of long-term waste site caps for and regions

Wake losses optimization of offshore wind farms with moveable floating wind turbines

NARCIS (Netherlands)

S.F. Rodrigues; R. Teixeira Pinto (Rodrigo); M. Soleimanzadeh (Maryam); P.A.N. Bosman (Peter); P. Bauer (Pavol)

2015-01-01

htmlabstractIn the future, floating wind turbines could be used to harvest energy in deep offshore areas where higher wind mean speeds are observed. Currently, several floating turbine concepts are being designed and tested in small scale projects; in particular, one concept allows the turbine to

Wind Energy Conference, Boulder, Colo., April 9-11, 1980, Technical Papers

Science.gov (United States)

1980-03-01

Papers are presented concerning the technology, and economics of wind energy conversion systems. Specific topics include the aerodynamic analysis of the Darrieus rotor, the numerical calculation of the flow near horizontal-axis wind turbine rotors, the calculation of dynamic wind turbine rotor loads, markets for wind energy systems, an oscillating-wing windmill, wind tunnel tests of wind rotors, wind turbine generator wakes, the application of a multi-speed electrical generator to wind turbines, the feasibility of wind-powered systems for dairy farms, and wind characteristics over uniform and complex terrain. Attention is also given to performance tests of the DOE/NASA MOD-1 2000-kW wind turbine generator, the assessment of utility-related test data, offshore wind energy conversion systems, and the optimization of wind energy utilization economics through load management.

Comparative evaluation of different offshore wind turbine installation vessels for Korean west–south wind farm

Directory of Open Access Journals (Sweden)

Dang Ahn

2017-01-01

Full Text Available The purpose of this study is to evaluate various means of wind power turbines installation in the Korean west–south wind farm (Test bed 100 MW, Demonstrate site 400 MW. We presented the marine environment of the southwest offshore wind farm in order to decide the appropriate installation vessel to be used in this site. The various vessels would be WTIV (Wind turbine installation vessel, jack-up barge, or floating crane … etc. We analyzed the installation cost of offshore wind turbine and the transportation duration for each vessel. The analysis results showed the most suitable installation means for offshore wind turbine in the Korean west–south wind farm.

Mean and peak wind load reduction on heliostats

Energy Technology Data Exchange (ETDEWEB)

Peterka, J.A.; Tan, L.; Bienkiewcz, B.; Cermak, J.E.

1987-09-01

This report presents the results of wind-tunnel tests supported through the Solar Energy Research Institute (SERI) by the Office of Solar Thermal Technology of the US Department of Energy as part of the SERI research effort on innovative concentrators. As gravity loads on drive mechanisms are reduced through stretched-membrane technology, the wind-load contribution of the required drive capacity increases in percentage. Reduction of wind loads can provide economy in support structure and heliostat drive. Wind-tunnel tests have been directed at finding methods to reduce wind loads on heliostats. The tests investigated both mean and peak forces, and moments. A significant increase in ability to predict heliostat wind loads and their reduction within a heliostat field was achieved. In addition, a preliminary review of wind loads on parabolic dish collectors was conducted, resulting in a recommended research program for these type collectors. 42 refs., 38 figs., 1 tab.

Wind Tunnel Test of a Risk-Reduction Wing/Fuselage Model to Examine Juncture-Flow Phenomena

Science.gov (United States)

Kegerise, Michael A.; Neuhart, Dan H.

2016-01-01

A wing/fuselage wind-tunnel model was tested in the Langley 14- by 22-foot Subsonic Wind Tunnel in preparation for a highly-instrumented Juncture Flow Experiment to be conducted in the same facility. This test, which was sponsored by the NASA Transformational Tool and Technologies Project, is part of a comprehensive set of experimental and computational research activities to develop revolutionary, physics-based aeronautics analysis and design capability. The objectives of this particular test were to examine the surface and off-body flow on a generic wing/body combination to: 1) choose a final wing for a future, highly instrumented model, 2) use the results to facilitate unsteady pressure sensor placement on the model, 3) determine the area to be surveyed with an embedded laser-doppler velocimetry (LDV) system, 4) investigate the primary juncture corner- flow separation region using particle image velocimetry (PIV) to see if the particle seeding is adequately entrained and to examine the structure in the separated region, and 5) to determine the similarity of observed flow features with those predicted by computational fluid dynamics (CFD). This report documents the results of the above experiment that specifically address the first three goals. Multiple wing configurations were tested at a chord Reynolds number of 2.4 million. Flow patterns on the surface of the wings and in the region of the wing/fuselage juncture were examined using oil- flow visualization and infrared thermography. A limited number of unsteady pressure sensors on the fuselage around the wing leading and trailing edges were used to identify any dynamic effects of the horseshoe vortex on the flow field. The area of separated flow in the wing/fuselage juncture near the wing trailing edge was observed for all wing configurations at various angles of attack. All of the test objectives were met. The staff of the 14- by 22-foot Subsonic Wind Tunnel provided outstanding support and delivered

Ice Accretion on Wind Turbine Blades

DEFF Research Database (Denmark)

Hudecz, Adriána; Koss, Holger; Hansen, Martin Otto Laver

2013-01-01

In this paper, both experimental and numerical simulations of the effects of ice accretion on a NACA 64-618 airfoil section with 7° angle of attack are presented. The wind tunnel tests were conducted in a closed-circuit climatic wind tunnel at Force Technology in Denmark. The changes of aerodynamic...... forces were monitored as ice was building up on the airfoil for glaze, rime and mixed ice. In the first part of the numerical analysis, the resulted ice profiles of the wind tunnel tests were compared to profiles estimated by using the 2D ice accretion code TURBICE. In the second part, Ansys Fluent...... of the rime iced ice profile follows the streamlines quite well, disturbing the flow the least. The TURBICE analysis agrees fairly with the profiles produced during the wind tunnel testing....

Atmospheric Full Scale Testing of a Morphing Trailing Edge Flap System for Wind Turbine Blades

DEFF Research Database (Denmark)

Barlas, Athanasios; Aagaard Madsen, Helge

2015-01-01

at the Risø Campus of DTU Wind Energy in Denmark. The design and instrumentation of the wing section and the AFS are described. The general description and objectives of the rotating test rig at the Risø campus of DTU are presented, along with an overview of sensors on the setup and the test cases. The post-processing...... of data is discussed and results of steady, flap step and azimuth control flap cases are presented....

Wind turbine power performance verification in complex terrain and wind farms

DEFF Research Database (Denmark)

Friis Pedersen, Troels; Gjerding, S.; Enevoldsen, P.

2002-01-01

is a power performance verification procedure for individual wind turbines. The third is a power performance measurement procedure of whole wind farms, and the fourth is a power performance measurement procedurefor non-grid (small) wind turbines. This report presents work that was made to support the basis......The IEC/EN 61400-12 Ed 1 standard for wind turbine power performance testing is being revised. The standard will be divided into four documents. The first one of these is more or less a revision of the existing document on power performance measurementson individual wind turbines. The second one...... then been investigated in more detail. The work has given rise to a range of conclusionsand recommendations regarding: guaranties on power curves in complex terrain; investors and bankers experience with verification of power curves; power performance in relation to regional correction curves for Denmark...

FAST Model Calibration and Validation of the OC5- DeepCwind Floating Offshore Wind System Against Wave Tank Test Data: Preprint

Energy Technology Data Exchange (ETDEWEB)

Wendt, Fabian F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Robertson, Amy N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jonkman, Jason [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-08-09

During the course of the Offshore Code Comparison Collaboration, Continued, with Correlation (OC5) project, which focused on the validation of numerical methods through comparison against tank test data, the authors created a numerical FAST model of the 1:50-scale DeepCwind semisubmersible system that was tested at the Maritime Research Institute Netherlands ocean basin in 2013. This paper discusses several model calibration studies that were conducted to identify model adjustments that improve the agreement between the numerical simulations and the experimental test data. These calibration studies cover wind-field-specific parameters (coherence, turbulence), hydrodynamic and aerodynamic modeling approaches, as well as rotor model (blade-pitch and blade-mass imbalances) and tower model (structural tower damping coefficient) adjustments. These calibration studies were conducted based on relatively simple calibration load cases (wave only/wind only). The agreement between the final FAST model and experimental measurements is then assessed based on more-complex combined wind and wave validation cases.

IEA Wind Task 32: Wind Lidar Identifying and Mitigating Barriers to the Adoption of Wind Lidar

Directory of Open Access Journals (Sweden)

Andrew Clifton

2018-03-01

Full Text Available IEA Wind Task 32 exists to identify and mitigate barriers to the adoption of lidar for wind energy applications. It leverages ongoing international research and development activities in academia and industry to investigate site assessment, power performance testing, controls and loads, and complex flows. Since its initiation in 2011, Task 32 has been responsible for several recommended practices and expert reports that have contributed to the adoption of ground-based, nacelle-based, and floating lidar by the wind industry. Future challenges include the development of lidar uncertainty models, best practices for data management, and developing community-based tools for data analysis, planning of lidar measurements and lidar configuration. This paper describes the barriers that Task 32 identified to the deployment of wind lidar in each of these application areas, and the steps that have been taken to confirm or mitigate the barriers. Task 32 will continue to be a meeting point for the international wind lidar community until at least 2020 and welcomes old and new participants.

Wind tunnel experimental study on the effect of PAM on soil wind erosion control.

Science.gov (United States)

He, Ji-Jun; Cai, Qiang-Guo; Tang, Ze-Jun

2008-10-01

In recent years, high-molecular-weight anionic polyacrylamide (PAM) have been widely tested on a variety of soils, primarily in water erosion control. However, little information is available regarding the effectiveness of PAM on preventing soil loss from wind erosion. The research adopted room wind tunnel experiment, two kinds of soils were used which were from the agro-pastoral area of Inner Mongolia, the northwest of China, the clay content of soils were 22.0 and 13.7%, respectively. For these tests, all the treatments were performed under the condition of wind velocity of 14 m s(-1) and a blown angle of 8.75%, according to the actual situation of experimented area. The study results indicated that using PAM on the soil surface could enhance the capability of avoiding the wind erosion, at the same time, the effect of controlling wind soil erosion with 4 g m(-2) PAM was better than 2 g m(-2) PAM's. Economically, the 2 g m(-2) PAM used in soil surface can control wind erosion effectively in this region. The prophase PAM accumulated in soil could not improve the capability of avoiding the wind erosion, owing to the degradation of PAM in the soil and the continual tillage year after year. The texture of soil is a main factor influencing the capability of soil avoiding wind erosion. Soil with higher clay content has the higher capability of preventing soil from wind erosion than one with the opposite one under the together action of PAM and water.

Wind Tunnel Testing of a 120th Scale Large Civil Tilt-Rotor Model in Airplane and Helicopter Modes

Science.gov (United States)

Theodore, Colin R.; Willink, Gina C.; Russell, Carl R.; Amy, Alexander R.; Pete, Ashley E.

2014-01-01

In April 2012 and October 2013, NASA and the U.S. Army jointly conducted a wind tunnel test program examining two notional large tilt rotor designs: NASA's Large Civil Tilt Rotor and the Army's High Efficiency Tilt Rotor. The approximately 6%-scale airframe models (unpowered) were tested without rotors in the U.S. Army 7- by 10-foot wind tunnel at NASA Ames Research Center. Measurements of all six forces and moments acting on the airframe were taken using the wind tunnel scale system. In addition to force and moment measurements, flow visualization using tufts, infrared thermography and oil flow were used to identify flow trajectories, boundary layer transition and areas of flow separation. The purpose of this test was to collect data for the validation of computational fluid dynamics tools, for the development of flight dynamics simulation models, and to validate performance predictions made during conceptual design. This paper focuses on the results for the Large Civil Tilt Rotor model in an airplane mode configuration up to 200 knots of wind tunnel speed. Results are presented with the full airframe model with various wing tip and nacelle configurations, and for a wing-only case also with various wing tip and nacelle configurations. Key results show that the addition of a wing extension outboard of the nacelles produces a significant increase in the lift-to-drag ratio, and interestingly decreases the drag compared to the case where the wing extension is not present. The drag decrease is likely due to complex aerodynamic interactions between the nacelle and wing extension that results in a significant drag benefit.

Computational testing and design of materials for wind energy and structural applications

DEFF Research Database (Denmark)

Mishnaevsky, Leon

2012-01-01

The requirements to wind turbine blades and other elements are quite high, In the ideal case, a wind turbine should work for 20.30 years without or with minimum maintenance. That is why the damage resistance and strength of wind blade materials is of great importance. A way to enhance the strengt...

Small Wind Turbine Technology Assessment

International Nuclear Information System (INIS)

Avia Aranda, F.; Cruz Cruz, I.

1999-01-01

The result of the study carried out under the scope of the ATYCA project Test Plant of Wind Systems for Isolated Applications, about the state of art of the small wind turbine technology (wind turbines with swept area smaller than 40 m 2 ) is presented. The study analyzes the collected information on 60 models of wind turbines from 23 manufacturers in the worldwide market. Data from Chinese manufacturers, that have a large participation in the total number of small wind turbines in operation, are not included, due to the unavailability of the technical information. (Author) 15 refs

Drying of mango pulp in a dryer of laboratory tunnel type; Secado de pulpa de mango en un secador de laboratorio tipo tunel

Energy Technology Data Exchange (ETDEWEB)

Pacheco Resendiz, Oscar; Chagoyan Serrano, Jose; Flores I, Alfredo; Rodriguez M, Jose A [Universidad Autonoma de Baja California Sur (Mexico)

2000-07-01

The result of four tests of drying of mango pulp Kent are presented, which were carried out in a dryer of the tunnel type in constant conditions of temperature, speed and absolute humidity of the air. The temperatures at which the tests were conducted were 35, 40, 45 and 50 Celsius degrees. The average speed of the drying air was 2.35 m/s. For the four tests the drying variables were measured for the purpose of controlling the process. The tests were suspended after 10 hours. The initial and final moisture contents of the samples on a wet weight basis for the test at 35 were 87.04% and 58.94% for that at 40 were 87.42% and 17.25%, for that at 45 were 87.55% and 13.29%, and for that at 50 were 87.43% and 48%. The graphs of the evolution of moisture content of the samples dried under the specified conditions are compared. [Spanish] Se presentan los resultados de cuatro pruebas de secado de pulpa de mango Kent, las cuales se realizaron en un secador tipo tunel en condiciones constantes de temperatura, velocidad y humedad absoluta del aire. Las temperaturas empleadas fueron 35, 40, 45 y 50 grados Celsius y la velocidad del aire de secado fue de 2.35 m/s. Para las cuatro pruebas se midieron las variables de secado mencionadas con el fin de controlar el proceso. Las pruebas se suspendieron al cumplirse 10 h. Las humedades inicial y final base humeda de las muestras para la prueba de 35 fueron 87.04% y 58.94%, para la de 40 fueron 87.42% y 17.25% y para la de 45 fueron de 87.55% y 13.29% y para la de 50 fueron de 87.43% y 48%. Se comparan entre si las graficas de la evolucion del contenido de humedad de las muestras que se secaron a las condiciones ya mencionadas.

Advanced Performance Hydraulic Wind Energy

Science.gov (United States)

Jones, Jack A.; Bruce, Allan; Lam, Adrienne S.

2013-01-01

The Jet Propulsion Laboratory, California Institute of Technology, has developed a novel advanced hydraulic wind energy design, which has up to 23% performance improvement over conventional wind turbine and conventional hydraulic wind energy systems with 5 m/sec winds. It also has significant cost advantages with levelized costs equal to coal (after carbon tax rebate). The design is equally applicable to tidal energy systems and has passed preliminary laboratory proof-of-performance tests, as funded by the Department of Energy.

Analysis of trends between solar wind velocity and energetic electron fluxes at geostationary orbit using the reverse arrangement test

Science.gov (United States)

Aryan, Homayon; Boynton, Richard J.; Walker, Simon N.

2013-02-01

A correlation between solar wind velocity (VSW) and energetic electron fluxes (EEF) at the geosynchronous orbit was first identified more than 30 years ago. However, recent studies have shown that the relation between VSW and EEF is considerably more complex than was previously suggested. The application of process identification technique to the evolution of electron fluxes in the range 1.8 - 3.5 MeV has also revealed peculiarities in the relation between VSW and EEF at the geosynchronous orbit. It has been revealed that for a constant solar wind density, EEF increase with VSW until a saturation velocity is reached. Beyond the saturation velocity, an increase in VSW is statistically not accompanied with EEF enhancement. The present study is devoted to the investigation of saturation velocity and its dependency upon solar wind density using the reverse arrangement test. In general, the results indicate that saturation velocity increases as solar wind density decreases. This implies that solar wind density plays an important role in defining the relationship between VSW and EEF at the geosynchronous orbit.

Wind turbine optimal control during storms

International Nuclear Information System (INIS)

Petrović, V; Bottasso, C L

2014-01-01

This paper proposes a control algorithm that enables wind turbine operation in high winds. With this objective, an online optimization procedure is formulated that, based on the wind turbine state, estimates those extremal wind speed variations that would produce maximal allowable wind turbine loads. Optimization results are compared to the actual wind speed and, if there is a danger of excessive loading, the wind turbine power reference is adjusted to ensure that loads stay within allowed limits. This way, the machine can operate safely even above the cut-out wind speed, thereby realizing a soft envelope-protecting cut-out. The proposed control strategy is tested and verified using a high-fidelity aeroservoelastic simulation model

Generic 12-Bus Test System for Wind Power Integration Studies

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz; Altin, Müfit; Göksu, Ömer

2012-01-01

, inertial response, frequency control, damping of electromechanical oscillations, balanced and unbalanced fault management, etc. Hence, the power system components: conventional power plants with controls, transmission lines, transformers and loads should be represented accurately to achieve realistic power......High wind power penetration levels into power systems requires an appropriate power system model when assessing impact on the overall system stability. The model should capture the wide range of dynamics related to the wind integration studies, such as voltage control, synchronizing power control...... system characteristics. Additionally, the power system model should be simple and computationally manageable in order to simulate multiple scenarios with different control parameters in a reasonable time. In this paper, a generic power system model is presented in order to comprehend the wind integration...

Particle transport patterns of short-distance soil erosion by wind-driven rain, rain and wind

Science.gov (United States)

Marzen, Miriam; Iserloh, Thomas; de Lima, João L. M. P.; Ries, Johannes B.

2015-04-01

Short distance erosion of soil surface material is one of the big question marks in soil erosion studies. The exact measurement of short-distance transported soil particles, prior to the occurrence of overland flow, is a challenge to soil erosion science due to the particular requirements of the experimental setup and test procedure. To approach a quantification of amount and distance of each type of transport, we applied an especially developed multiple-gutter system installed inside the Trier Portable Wind and Rainfall Simulator (PWRS). We measured the amount and travel distance of soil particles detached and transported by raindrops (splash), wind-driven rain (splash-saltation and splash-drift) and wind (saltation). The test setup included three different erosion agents (rain/ wind-driven rain/ wind), two substrates (sandy/ loamy), three surface structures (grain roughness/ rills lengthwise/ rills transversal) and three slope angles (0°/+7°/-7°). The results present detailed transport patterns of the three erosion agents under the varying soil and surface conditions up to a distance of 1.6 m. Under the applied rain intensity and wind velocity, wind-driven rain splash generates the highest erosion. The erodibility and travel distance of the two substrates depend on the erosion agent. The total erosion is slightly higher for the slope angle -7° (downslope), but for wind-driven rain splash, the inclination is not a relevant factor. The effect of surface structures (rills) changes with traveling distance. The wind driven rain splash generates a much higher amount of erosion and a further travel distance of the particles due to the combined action of wind and rain. The wind-driven rain factor appears to be much more significant than the other factors. The study highlights the effects of different erosion agents and surface parameters on short-distance particle transport and the powerful impact of wind-driven rain on soil erosion.

Wind speed reductions by large-scale wind turbine deployments lower turbine efficiencies and set low wind power potentials

Science.gov (United States)

Miller, Lee; Kleidon, Axel

2017-04-01

Wind turbines generate electricity by removing kinetic energy from the atmosphere. Large numbers of wind turbines are likely to reduce wind speeds, which lowers estimates of electricity generation from what would be presumed from unaffected conditions. Here, we test how well wind power potentials that account for this effect can be estimated without explicitly simulating atmospheric dynamics. We first use simulations with an atmospheric general circulation model (GCM) that explicitly simulates the effects of wind turbines to derive wind power limits (GCM estimate), and compare them to a simple approach derived from the climatological conditions without turbines [vertical kinetic energy (VKE) estimate]. On land, we find strong agreement between the VKE and GCM estimates with respect to electricity generation rates (0.32 and 0.37 We m-2) and wind speed reductions by 42 and 44%. Over ocean, the GCM estimate is about twice the VKE estimate (0.59 and 0.29 We m-2) and yet with comparable wind speed reductions (50 and 42%). We then show that this bias can be corrected by modifying the downward momentum flux to the surface. Thus, large-scale limits to wind power can be derived from climatological conditions without explicitly simulating atmospheric dynamics. Consistent with the GCM simulations, the approach estimates that only comparatively few land areas are suitable to generate more than 1 We m-2 of electricity and that larger deployment scales are likely to reduce the expected electricity generation rate of each turbine. We conclude that these atmospheric effects are relevant for planning the future expansion of wind power.

Damping Estimation of a Prototype Bucket Foundation for Offshore Wind Turbines Identified by Full Scale Testing

DEFF Research Database (Denmark)

Damgaard, Mads; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard

2013-01-01

-3.0 MW offshore wind turbine installed on a prototype bucket foundation. The foundation and the turbine tower are equipped with a monitoring system with 15 Kinemetrics force balance accelerometers and a Digitexx acquisition system. Using free vibration decays from “rotor-stop” tests and operational modal...

Field Testing of LIDAR-Assisted Feedforward Control Algorithms for Improved Speed Control and Fatigue Load Reduction on a 600-kW Wind Turbine: Preprint

Energy Technology Data Exchange (ETDEWEB)

Kumar, Avishek A.; Bossanyi, Ervin A.; Scholbrock, Andrew K.; Fleming, Paul; Boquet, Mathieu; Krishnamurthy, Raghu

2015-12-14

A severe challenge in controlling wind turbines is ensuring controller performance in the presence of a stochastic and unknown wind field, relying on the response of the turbine to generate control actions. Recent technologies such as LIDAR, allow sensing of the wind field before it reaches the rotor. In this work a field-testing campaign to test LIDAR Assisted Control (LAC) has been undertaken on a 600-kW turbine using a fixed, five-beam LIDAR system. The campaign compared the performance of a baseline controller to four LACs with progressively lower levels of feedback using 35 hours of collected data.

Analyses of CsI aerosol deposition tests in WIND project with ART and VICTORIA codes

International Nuclear Information System (INIS)

Yuchi, Y.; Shibazaki, H.; Kudo, T.

2000-01-01

Deposition behavior of cesium iodide (CsI) was analyzed with ART and VICTORIA-92 codes for a test of the aerosol re-vaporization test series performed in WIND project at JAERI. In the test analyzed, CsI aerosol was injected into piping of test section where metaboric acid (HBO 2 ) was placed in advance on the floor area. It was confirmed in the present analysis that similar results on the CsI deposition were obtained between ART and VICTORIA when influences of chemical interactions were negligibly small. The analysis with VICTORIA agreed satisfactorily with the test results in analytical cases that cesium metaborate (CsBO 2 ) was injected into the test section instead of CsI to simulate the pre-existence of HBO 2 effect. (author)

Plans for Testing the NREL Unsteady Aerodynamics Experiment 10m Diameter HAWT in the NASA Ames Wind Tunnel: Minutes, Conclusions, and Revised Text Matrix from the 1st Science Panel Meeting

Energy Technology Data Exchange (ETDEWEB)

Simms, D.; Schreck, S.; Hand, M.; Fingersh, L.; Cotrell, J.; Pierce, K.; Robinson, M.

2000-08-28

Currently, the NREL Unsteady Aerodynamics Experiment (UAE) research turbine is scheduled to enter the NASA Ames 80-ft x 120-ft wind tunnel in early 2000. To prepare for this 3-week test, a Science Panel meeting was convened at the National Wind Technology Center (NWTC) in October 1998. During this meeting, the Science Panel and representatives from the wind energy community provided numerous detailed recommendations regarding test activities and priorities. The Unsteady Aerodynamics team of the NWTC condensed this guidance and drafted a detailed test plan. This test plan represents an attempt to balance diverse recommendations received from the Science Panel meeting, while taking into account multiple constraints imposed by the UAE research turbine, the NASA Ames 80-ft x 120-ft wind tunnel, and other sources. The NREL-NASA Ames wind tunnel tests will primarily be focused on obtaining rotating blade pressure data. NREL has been making these types of measurements since 1987 and has considerable experience in doing so. The purpose of this wind tunnel test is to acquire accurate quantitative aerodynamic and structural measurements, on a wind turbine that is geometrically and dynamically representative of full-scale machines, in an environment free from pronounced inflow anomalies. These data will be exploited to develop and validate enhanced engineering models for designing and analyzing advanced wind energy machines.

Invited article: Electric solar wind sail: toward test missions.

Science.gov (United States)

Janhunen, P; Toivanen, P K; Polkko, J; Merikallio, S; Salminen, P; Haeggström, E; Seppänen, H; Kurppa, R; Ukkonen, J; Kiprich, S; Thornell, G; Kratz, H; Richter, L; Krömer, O; Rosta, R; Noorma, M; Envall, J; Lätt, S; Mengali, G; Quarta, A A; Koivisto, H; Tarvainen, O; Kalvas, T; Kauppinen, J; Nuottajärvi, A; Obraztsov, A

2010-11-01

The electric solar wind sail (E-sail) is a space propulsion concept that uses the natural solar wind dynamic pressure for producing spacecraft thrust. In its baseline form, the E-sail consists of a number of long, thin, conducting, and centrifugally stretched tethers, which are kept in a high positive potential by an onboard electron gun. The concept gains its efficiency from the fact that the effective sail area, i.e., the potential structure of the tethers, can be millions of times larger than the physical area of the thin tethers wires, which offsets the fact that the dynamic pressure of the solar wind is very weak. Indeed, according to the most recent published estimates, an E-sail of 1 N thrust and 100 kg mass could be built in the rather near future, providing a revolutionary level of propulsive performance (specific acceleration) for travel in the solar system. Here we give a review of the ongoing technical development work of the E-sail, covering tether construction, overall mechanical design alternatives, guidance and navigation strategies, and dynamical and orbital simulations.

Partial analysis of wind power limit for large disturbance using fixed speed wind turbine

International Nuclear Information System (INIS)

Santos Fuentefria, Ariel; Cairo Rodriguez, Daniel; Boza Valerino, Juan Gualberto

2014-01-01

The amount of wind power that allow an electric network without losing his stability as known as wind power limit. The wind power limit fundamentally depends on the wind turbine technology and the weakness level of the system. To know the system behaviors in dynamic performance having into account the worst disturbance is a very important matter, a short circuit in one of the most power transference line or the loss of a large generation unit was a large disturbance that can affect system stability. The wind power limit may change with the nature of the disturbance. To know the wind power limit considering this conditions allow use the wind at maximum level. In the present paper the behavior of fixed speed wind turbine for different fault types is analyzed, at those conditions, the wind power is increasing until the system become voltage unstable. For the analysis the IEEE 14 Bus Test Case is used. The Power System Analysis Toolbox (PSAT) package is used for the simulation. (author)

TOPFARM wind farm optimization tool

Energy Technology Data Exchange (ETDEWEB)

Rethore, P.-E.; Fuglsang, P.; Larsen, Torben J.; Buhl, T.; Larsen, Gunner C.

2011-02-15

A wind farm optimization framework is presented in detail and demonstrated on two test cases: 1) Middelgrunden and 2) Stags Holt/Coldham. A detailed flow model describing the instationary flow within a wind farm is used together with an aeroelastic model to determine production and fatigue loading of wind farm wind turbines. Based on generic load cases, the wind farm production and fatigue evaluations are subsequently condensed in a large pre-calculated database for rapid calculation of lifetime equivalent loads and energy production in the optimization loop. The objective function defining the optimization problem includes elements as energy production, turbine degradation, operation and maintenance costs, electrical grid costs and foundation costs. The objective function is optimized using a dedicated multi fidelity approach with the locations of individual turbines in the wind farm spanning the design space. The results are over all satisfying and are giving some interesting insights on the pros and cons of the design choices. They show in particular that the inclusion of the fatigue loads costs give rise to some additional details in comparison with pure power based optimization. The Middelgrunden test case resulted in an improvement of the financial balance of 2.1 M Euro originating from a very large increase in the energy production value of 9.3 M Euro mainly counterbalanced by increased electrical grid costs. The Stags Holt/Coldham test case resulted in an improvement of the financial balance of 3.1 M Euro. (Author)

Autonomous Aerial Sensors for Wind Power Meteorology

DEFF Research Database (Denmark)

Giebel, Gregor; Schmidt Paulsen, Uwe; Reuder, Joachim

2011-01-01

, UAVs could be quite cost-effective. In order to test this assumption and to test the limits of UAVs for wind power meteorology, this project assembles four different UAVs from four participating groups. Risø has built a lighter-than-air kite with a long tether, Bergen University flies a derivative......This paper describes a new approach for measurements in wind power meteorology using small unmanned flying platforms. Large-scale wind farms, especially offshore, need an optimisation between installed wind power density and the losses in the wind farm due to wake effects between the turbines. Good...... movement. In any case, a good LIDAR or SODAR will cost many tenthousands of euros. Another current problem in wind energy is the coming generation of wind turbines in the 10-12MW class, with tip heights of over 200m. Very few measurement masts exist to verify our knowledge of atmospheric physics, and most...

Wind effects on long-span bridges: Probabilistic wind data format for buffeting and VIV load assessments

Science.gov (United States)

Hoffmann, K.; Srouji, R. G.; Hansen, S. O.

2017-12-01

The technology development within the structural design of long-span bridges in Norwegian fjords has created a need for reformulating the calculation format and the physical quantities used to describe the properties of wind and the associated wind-induced effects on bridge decks. Parts of a new probabilistic format describing the incoming, undisturbed wind is presented. It is expected that a fixed probabilistic format will facilitate a more physically consistent and precise description of the wind conditions, which in turn increase the accuracy and considerably reduce uncertainties in wind load assessments. Because the format is probabilistic, a quantification of the level of safety and uncertainty in predicted wind loads is readily accessible. A simple buffeting response calculation demonstrates the use of probabilistic wind data in the assessment of wind loads and responses. Furthermore, vortex-induced fatigue damage is discussed in relation to probabilistic wind turbulence data and response measurements from wind tunnel tests.

The Effect of Wind Forcing on Modeling Coastal Circulation at a Marine Renewable Test Site

Directory of Open Access Journals (Sweden)

Lei Ren

2017-12-01

Full Text Available The hydrodynamic circulation in estuaries is primarily driven by tides, river inflows and surface winds. While tidal and river data can be quite easily obtained for input to hydrodynamic models, sourcing accurate surface wind data is problematic. Inaccurate wind data can lead to inaccuracies in the surface currents computed by three-dimensional hydrodynamic models. In this research, a high-resolution wind model was coupled with a three-dimensional hydrodynamic model of Galway Bay, a semi-enclosed estuary on the west coast of Ireland, to investigate the effect of wind forcing on model accuracy. Two wind-forcing conditions were investigated: (1 using wind data measured onshore on the NUI Galway campus (NUIG and (2 using offshore wind data provided by a high resolution wind model (HR. A scenario with no wind forcing (NW was also assessed. The onshore wind data varied with time but the speed and direction were applied across the full model domain. The modeled offshore wind fields varied with both time and space. The effect of wind forcing on modeled hydrodynamics was assessed via comparison of modeled surface currents with surface current measurements obtained from a High-Frequency (HF radar Coastal Ocean Dynamics Applications Radar (CODAR observation system. Results indicated that winds were most significant in simulating the north-south surface velocity component. The model using high resolution temporally- and spatially-varying wind data achieved better agreement with the CODAR surface currents than the model using the onshore wind measurements and the model without any wind forcing.

Atmospheric diffusion wind tunnel with automatic measurement

Energy Technology Data Exchange (ETDEWEB)

Maki, S; Sakai, J; Murata, E

1974-01-01

A wind tunnel which permits estimates of atmospheric diffusion is described. Smoke from power plant smoke stacks, for example, can be simulated and traced to determine the manner of diffusion in the air as well as the grade of dilution. The wind tunnel is also capable of temperature controlled diffusion tests in which temperature distribution inside the wind tunnel is controlled. A minimum wind velocity of 10 cm can be obtained with accuracy within plus or minus 0.05 percent using a controlled direct current motor; diffusion tests are often made at low wind velocity. Fully automatic measurements can be obtained by using a minicomputer so that the operation and reading of the measuring instruments can be remotely controlled from the measuring chamber. (Air Pollut. Abstr.)

Wind energy in a global world

DEFF Research Database (Denmark)

Hjuler Jensen, Peter

2007-01-01

For the past 25 years there has been a dramatic development in the wind energy sector, with regard to the increase in overall utilisation of wind energy as well as technological development, the development of markets and expectations to the role of wind energy in the global electricity supply...... system. The purpose of this paper is to outline developments in the global capacity of wind energy this past quarter of a century, including technology, market aspects, scientific developments, testing and certification, formulation of standards and scenarios for the future development of wind energy...

Design and test of box girder for a large wind turbine blade

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Per H.; Tesauro, A.; Bitsche, R. [Technical Univ. of Denmark. DTU Wind Energy, DTU Risoe Campus, Roskilde (Denmark)] [and others

2012-09-15

This report is covering the structural design and full scale test of a box girder as a part of the project ''Demonstration of new blade design using manufacturing process simulations'' supported by the EUDP program. A box girder with a predetermined outer geometry was designed using new inventions, which create an inner structure in the box girder. With a combination of advanced FEM analysis and the inventions it was possible to reduce the material thickness of the cap by up to 40%. The new design of the box girder was manufactured at SSP Technology A/S, where it was demonstrated that the manufacturing process could include the new inventions. Subsequently the box girder was transported to the blade test facility at DTU Wind Energy. A series of test was performed with the blade to investigate the behaviour during loading, and finally the girder was loaded to ultimate failure. The report includes the description of the test setup, the test and an overview over the results from the test performed on the box girder. During the final test the box girder failed at 58 % of the expected ultimate load. Unfortunately, no definite conclusion could be made concerning the failure mechanism. (Author)

Wind power development field test project at Ebetsu plant of Oji Paper Co., Ltd. Close survey on wind conditions; Oji seishi Ebetsu kojo ni okeru furyoku kaihatsu field test jigyo (fukyo seisa) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

A survey was made on wind conditions at the Ebetsu plant of Oji Paper Co., Ltd., on the assumption that a demonstrative equipment of a wind power generation system was installed in the plant. The survey period was one year from Oct., 1998 to Sept., 1999. The observations were carried out on the average wind velocity, average wind direction, standard deviation of velocity, and the maximum instantaneous wind velocity. With a fixed point observation at 20 m above ground, and with the minimum observation time unit of 10 minutes, an average value during the 10 minutes was determined as the measurement of each category. However, the maximum instantaneous wind velocity was determined on the measurement with the minimum observation time unit of 2 seconds. The average wind velocity was 3.2 m/s, the maximum wind velocity during the period was 34 m/s, and the prevailing wind direction was SSE (25.6%), while the total occurrence probability on the wind axis with NW-SE as the main axis was 62.9%. The intensity of turbulence was 0.28 at a wind velocity of 2.0 m/s or above and was 0.25 at 4.0 m/s or above. An estimated annual operation rate of a windmill was 37-59% using the rated value of a 150 kW, 300 kW and 750 kW class windmills. (NEDO)

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

Science.gov (United States)

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.

A nonlinear dynamics approach for incorporating wind-speed patterns into wind-power project evaluation.

Science.gov (United States)

Huffaker, Ray; Bittelli, Marco

2015-01-01

Wind-energy production may be expanded beyond regions with high-average wind speeds (such as the Midwest U.S.A.) to sites with lower-average speeds (such as the Southeast U.S.A.) by locating favorable regional matches between natural wind-speed and energy-demand patterns. A critical component of wind-power evaluation is to incorporate wind-speed dynamics reflecting documented diurnal and seasonal behavioral patterns. Conventional probabilistic approaches remove patterns from wind-speed data. These patterns must be restored synthetically before they can be matched with energy-demand patterns. How to accurately restore wind-speed patterns is a vexing problem spurring an expanding line of papers. We propose a paradigm shift in wind power evaluation that employs signal-detection and nonlinear-dynamics techniques to empirically diagnose whether synthetic pattern restoration can be avoided altogether. If the complex behavior of observed wind-speed records is due to nonlinear, low-dimensional, and deterministic system dynamics, then nonlinear dynamics techniques can reconstruct wind-speed dynamics from observed wind-speed data without recourse to conventional probabilistic approaches. In the first study of its kind, we test a nonlinear dynamics approach in an application to Sugarland Wind-the first utility-scale wind project proposed in Florida, USA. We find empirical evidence of a low-dimensional and nonlinear wind-speed attractor characterized by strong temporal patterns that match up well with regular daily and seasonal electricity demand patterns.

An adapted blockage factor correlation approach in wind tunnel experiments of a Savonius-style wind turbine

International Nuclear Information System (INIS)

Roy, Sukanta; Saha, Ujjwal K.

2014-01-01

Highlights: • Significance of the blockage correction in wind tunnel experiments of Savonius-style wind turbine. • Adaptation of blockage factor correlations under open type test sections for blockage ratio of 21.16%. • Effectiveness of adapted correlations for smaller blockage ratios (BRs) of 16% and 12.25%. • Estimate the magnitude of the blockage correction under various loading conditions for each BR. • Variation of blockage correction factor with respect to tip speed ratio and BR. - Abstract: An investigation into the blockage correction effects in wind tunnel experiments of a small-scale wind energy conversion system in an open type test section is carried out. The energy conversion system includes a Savonius-style wind turbine (SSWT) and a power measurement assembly. As the available correlations for the closed type test sections may not be appropriate for the open test section under dynamic loading conditions, new correlations are adapted for the blockage correction factors with free stream wind speed, turbine rotational speed and variable load applied to the turbine to quantify the energy conversion coefficients more precisely. These are obtained for a blockage ratio of 21.16% through a comparison of present experimental data with those of established experimental data under dynamic loading conditions. Further, the accuracy of the adapted correlations is substantiated into the experiments with smaller blockage ratios of 16% and 12.25%. The relationships of the tip speed ratios and blockage ratios with the blockage correction factor are also discussed. Using these correlations, this study provides evidence of increase of blockage correction in the range 1–10% with the increase of both tip speed ratio and blockage ratio. The results also indicate that for blockage ratios approaching 10 and tip speed ratios below 0.5, the blockage effects are almost negligible in the open type test sections

Hybrid Test Bed of Wind Electric Generator with Photovoltaic Panels

OpenAIRE

G.D.Anbarasi Jebaselvi; S.Paramasivam

2014-01-01

Driven by the increasing costs of power production and decreasing fossil fuel reserves with the addition of global environmental concerns, renewable energy is now becoming significant fraction of total electricity production in the world. Advancements in the field of wind electric generator technology and power electronics help to achieve rapid progress in hybrid power system which mainly involves wind, solar and diesel energy with a good battery back-up. Here the discussion brings about the ...

Wind-wave modelling aspects within complicate topography

Directory of Open Access Journals (Sweden)

S. Christopoulos

Full Text Available Wave forecasting aspects for basins with complicate geomorphology, such as the Aegean Sea, are investigated through an intercomparison study. The efficiency of the available wind models (ECMWF, UKMO to reproduce wind patterns over special basins, as well as three wave models incorporating different physics and characteristics (WAM, AUT, WACCAS, are tested for selected storm cases representing the typical wind situations over the basin. From the wave results, discussed in terms of time-series and statistical parameters, the crucial role is pointed out of the wind resolution and the reliability of the different wave models to estimate the wave climate in such a basin. The necessary grid resolution is also tested, while for a specific test case (December 1991 ERS-1 satellite data are compared with those of the model.

Towards Flight Testing of Remotely Controlled Surfkites for Wind Energy Generation

NARCIS (Netherlands)

Lansdorp, B.; Ruiterkamp, R.; Ockels, W.

2007-01-01

Non-powered flight vehicles such as kites can provide a means of transmitting wind energy from higher altitudes to the ground via tethers. Although there is increased world wide interest for systems to extract wind energy from higher altitudes with kites, research into kite properties such as the

Wind Conditions for Wind Farm Hanstholm

DEFF Research Database (Denmark)

Pena Diaz, Alfredo; Hahmann, Andrea N.; Mann, Jakob

The net annual energy production (AEP) of the Hanstholm Wind Farm is 158 GWh per year for the Siemens SWT-3.6-120 turbine and 140 GWh for the Vestas V112-3.0 turbine. These values have an uncertainty (standard deviation) of 6%. This result is mainly based on the data for Risø DTU’s test station...... at Høvsøre where wind speeds are measured at approximately the same height as the turbines at Hanstholm and where the terrain is similar. On top of that meso-scale modeling has been used to extrapolate the climatology from Høvsøre to Hanstholm increasing the AEP by almost 6% compared to just using...... the Høvsøre climatology directly. This method of extrapolation is rather new, but several older investigations indicate that the wind resource at Hanstholm is slightly higher than at Høvsøre. The work is carried out for Grontmij-Carl Bro according to a contract dated January 18th 2011....

Wind resource analysis. Annual report

Energy Technology Data Exchange (ETDEWEB)

Hardy, D. M.

1978-12-01

FY78 results of the Wind Resource Analyses task of the ERAB are described. Initial steps were taken to acquire modern atmosphere models of near-surface wind flow and primary data sets used in previous studies of national and regional wind resources. Because numerous assumptions are necessary to interpret available data in terms of wind energy potential, conclusions of previous studies differ considerably. These data analyses may be improved by future SERI research. State-of-the-art atmosphere models are a necessary component of the SERI wind resource analyses capacity. However, these methods also need to be tested and verified in diverse applications. The primary data sets and principal features of the models are discussed.

Wind turbine power performance verification in complex terrain and wind farms

Energy Technology Data Exchange (ETDEWEB)

Friis Pedersen, T.; Gjerding, S.; Ingham, P.; Enevoldsen, P.; Kjaer Hansen, J.; Kanstrup Joergensen, H.

2002-04-01

The IEC/EN 61400-12 Ed 1 standard for wind turbine power performance testing is being revised. The standard will be divided into four documents. The first one of these is more or less a revision of the existing document on power performance measurements on individual wind turbines. The second one is a power performance verification procedure for individual wind turbines. The third is a power performance measurement procedure of whole wind farms, and the fourth is a power performance measurement procedure for non-grid (small) wind turbines. This report presents work that was made to support the basis for this standardisation work. The work addressed experience from several national and international research projects and contractual and field experience gained within the wind energy community on this matter. The work was wide ranging and addressed 'grey' areas of knowledge regarding existing methodologies, which has then been investigated in more detail. The work has given rise to a range of conclusions and recommendations regarding: guaranties on power curves in complex terrain; investors and bankers experience with verification of power curves; power performance in relation to regional correction curves for Denmark; anemometry and the influence of inclined flow. (au)

Experimental Study on New Multi-Column Tension-Leg-Type Floating Wind Turbine

Science.gov (United States)

Zhao, Yong-sheng; She, Xiao-he; He, Yan-ping; Yang, Jian-min; Peng, Tao; Kou, Yu-feng

2018-04-01

Deep-water regions often have winds favorable for offshore wind turbines, and floating turbines currently show the greatest potential to exploit such winds. This work established proper scaling laws for model tests, which were then implemented in the construction of a model wind turbine with optimally designed blades. The aerodynamic, hydrodynamic, and elastic characteristics of the proposed new multi-column tension-leg-type floating wind turbine (WindStar TLP system) were explored in the wave tank testing of a 1:50 scale model at the State Key Laboratory of Ocean Engineering at Shanghai Jiao Tong University. Tests were conducted under conditions of still water, white noise waves, irregular waves, and combined wind, wave, and current loads. The results established the natural periods of the motion, damping, motion response amplitude operators, and tendon tensions of the WindStar TLP system under different environmental conditions, and thus could serve as a reference for further research. Key words: floating wind turbine, model test, WindStar TLP, dynamic response

Main results from Risoe's wind-diesel programme 1984-1990

International Nuclear Information System (INIS)

Lundsager, P.; Christensen, C.J.

1991-12-01

The report presents the results of the wind-diesel work done in projects at Risoe National Laboratory during the years 1984-90, including important earlier publications as appendices. The partners in the original joint project were Risoe National Laboratory, Denmark, and Chalmers University of Technology, Sweden. Chalmers has constructed and laboratory tested an advanced wind-diesel-battery system with variable speed operation of the wind turbine, while Risoe has established a flexible and versatile wind-diesel test facility and field tested Chalmers system. As part of the subsequent EFP projects Risoe designed and constructed a simple wind-diesel system without storage, characterized by several innovative features. This concept was part of a ''simple wind-diesel systems strategy'', in which immediate cost-effectiveness is ensured by the simplicity and reliability of the design. Dynamic computer models were developed for system design and analysis purposes, and a general logistic computer model was developed for the determination of fuel savings and power supply capabilities for a number of system configurations. In addition to a considerable body of experience the main results of activities are: A versatile wind-diesel test facility and a proposed standard wind-diesel test procedure. Two wind-diesel systems at each end of the spectrum of configurations. Computer models for logistic and dynamic modelling. The two systems represent the very simple system concept, believed to be a presently economically optimal configuration, and the very sophisticated concept believed to be a future optimal configuration. (au) (6 tabs., 67 ills., 25 refs.)

Characteristics of Control Laws Tested on the Semi-Span Super-Sonic Transport (S4T) Wind-Tunnel Model

Science.gov (United States)

Christhilf, David M.; Moulin, Boris; Ritz, Erich; Chen, P. C.; Roughen, Kevin M.; Perry, Boyd

2012-01-01

The Semi-Span Supersonic Transport (S4T) is an aeroelastically scaled wind-tunnel model built to test active controls concepts for large flexible supersonic aircraft in the transonic flight regime. It is one of several models constructed in the 1990's as part of the High Speed Research (HSR) Program. Control laws were developed for the S4T by M4 Engineering, Inc. and by Zona Technologies, Inc. under NASA Research Announcement (NRA) contracts. The model was tested in the NASA-Langley Transonic Dynamics Tunnel (TDT) four times from 2007 to 2010. The first two tests were primarily for plant identification. The third entry was used for testing control laws for Ride Quality Enhancement, Gust Load Alleviation, and Flutter Suppression. Whereas the third entry only tested FS subcritically, the fourth test demonstrated closed-loop operation above the open-loop flutter boundary. The results of the third entry are reported elsewhere. This paper reports on flutter suppression results from the fourth wind-tunnel test. Flutter suppression is seen as a way to provide stability margins while flying at transonic flight conditions without penalizing the primary supersonic cruise design condition. An account is given for how Controller Performance Evaluation (CPE) singular value plots were interpreted with regard to progressing open- or closed-loop to higher dynamic pressures during testing.

Using wind tunnels to predict bird mortality in wind farms: the case of griffon vultures.

Science.gov (United States)

de Lucas, Manuela; Ferrer, Miguel; Janss, Guyonne F E

2012-01-01

Wind farms have shown a spectacular growth during the last 15 years. Avian mortality through collision with moving rotor blades is well-known as one of the main adverse impacts of wind farms. In Spain, the griffon vulture incurs the highest mortality rates in wind farms. As far as we know, this study is the first attempt to predict flight trajectories of birds in order to foresee potentially dangerous areas for wind farm development. We analyse topography and wind flows in relation to flight paths of griffon vultures, using a scaled model of the wind farm area in an aerodynamic wind tunnel, and test the difference between the observed flight paths of griffon vultures and the predominant wind flows. Different wind currents for each wind direction in the aerodynamic model were observed. Simulations of wind flows in a wind tunnel were compared with observed flight paths of griffon vultures. No statistical differences were detected between the observed flight trajectories of griffon vultures and the wind passages observed in our wind tunnel model. A significant correlation was found between dead vultures predicted proportion of vultures crossing those cells according to the aerodynamic model. Griffon vulture flight routes matched the predominant wind flows in the area (i.e. they followed the routes where less flight effort was needed). We suggest using these kinds of simulations to predict flight paths over complex terrains can inform the location of wind turbines and thereby reduce soaring bird mortality.

Analyses of CsI aerosol deposition in aerosol behavior tests in WIND project

International Nuclear Information System (INIS)

Kudo, Tamotsu; Shibazaki, Hiroaki; Hidaka, Akihide

1999-01-01

The aerosol deposition tests have been performed in WIND project at JAERI to characterize the aerosol behavior. The aerosol deposition tests named WAV1-D and WAV2-D were analyzed by aerosol behavior analysis codes, JAERI's ART and SNL's VICTORIA. The comparison calculation was performed for the confirmation of the analytical capabilities of the both codes and improvement of the models in ART. The deposition mass calculated by ART was larger than that by VICTORIA. This discrepancy is caused by differences in model for FP vapor condensation onto the wall surface. In the WAV2-D test, in which boric acid was placed on the floor area of the test section prior to the deposition phase to simulate the PWR primary coolant, there was a discrepancy in deposition mass between analytical results in both codes and experimental results. The discrepancy may be caused by existence of boric acid which is not considered in the codes. (author)

Performance of Wind Pump Prototype

African Journals Online (AJOL)

Mulu

Mekelle University, Mekelle, Ethiopia (*mul_at@yahoo.com). ABSTRACT. A wind ... balanced rotor power and reciprocating pump, hence did not consider the effect of pump size. ... Keywords: Wind pump, Windmill, Performance testing, Pump efficiency, Pump discharge, ... Unfortunately, in rural places, where the houses are.

Annotated bibliography of literature relating to wind transport of plutonium-contaminated soils at the Nevada Test Site

International Nuclear Information System (INIS)

Lancaster, N.; Bamford, R.

1993-12-01

During the period from 1954 through 1963, a number of tests were conducted on the Nevada Test Site (NTS) and Tonopah Test Range (TTR) to determine the safety of nuclear devices with respect to storage, handling, transport, and accidents. These tests were referred to as ''safety shots.'' ''Safety'' in this context meant ''safety against fission reaction.'' The safety tests were comprised of chemical high explosive detonations with components of nuclear devices. The conduct of these tests resulted in the dispersion of plutonium, and some americium over areas ranging from several tens to several hundreds of hectares. Of the various locations used for safety tests, the site referred to as ''Plutonium Valley'' was subject to a significant amount of plutonium contamination. Plutonium Valley is located in Area 11 on the eastern boundary of the NTS at an elevation of about 1036 m (3400 ft). Plutonium Valley was the location of four safety tests (A,B,C, and D) conducted during 1956. A major environmental, health, and safety concern is the potential for inhalation of Pu 239,240 by humans as a result of airborne dust containing Pu particles. Thus, the wind transport of Pu 239,240 particles has been the subject of considerable research. This annotated bibliography was created as a reference guide to assist in the better understanding of the environmental characteristics of Plutonium Valley, the safety tests performed there, the processes and variables involved with the wind transport of dust, and as an overview of proposed clean-up procedures

Model tests of wind turbine with a vertical axis of rotation type Lenz 2

Directory of Open Access Journals (Sweden)

Zwierzchowski Jaroslaw

2017-01-01

Full Text Available A building design of vertical axis wind turbines (VAWT was presented in the article. The construction and operating principle of a wind turbine were described therein. Two VAWT turbine models were compared, i.a. Darrieus and Lenz2, taking their strengths and weaknesses into consideration. 3D solid models of turbine components were presented with the use of SolidWorks software. Using CFD methods, the air flow on two aerodynamic fins, symmetrical and asymmetrical, at different angles of attack were tested. On the basis of flow simulation conducted in FlowSimulation, an asymmetrical fin was chosen as the one showing greater load bearing capacities. Due to the uncertainty of trouble-free operation of Darrieus turbine on construction elements creating the basis thereof, a 3D model of Lenz2 turbine was constructed, which is more reliable and makes turbine self-start possible. On the basis of the research, components were designed and technical docu mentation was compiled.

Model tests of wind turbine with a vertical axis of rotation type Lenz 2

Science.gov (United States)

Zwierzchowski, Jaroslaw; Laski, Pawel Andrzej; Blasiak, Slawomir; Takosoglu, Jakub Emanuel; Pietrala, Dawid Sebastian; Bracha, Gabriel Filip; Nowakowski, Lukasz

A building design of vertical axis wind turbines (VAWT) was presented in the article. The construction and operating principle of a wind turbine were described therein. Two VAWT turbine models were compared, i.a. Darrieus and Lenz2, taking their strengths and weaknesses into consideration. 3D solid models of turbine components were presented with the use of SolidWorks software. Using CFD methods, the air flow on two aerodynamic fins, symmetrical and asymmetrical, at different angles of attack were tested. On the basis of flow simulation conducted in FlowSimulation, an asymmetrical fin was chosen as the one showing greater load bearing capacities. Due to the uncertainty of trouble-free operation of Darrieus turbine on construction elements creating the basis thereof, a 3D model of Lenz2 turbine was constructed, which is more reliable and makes turbine self-start possible. On the basis of the research, components were designed and technical docu mentation was compiled.

Wind Forces on Container Ships

DEFF Research Database (Denmark)

Andersen, Ingrid Marie Vincent

2012-01-01

An investigation of the wind forces acting on a 9,000+ TEU container ship has been carried out through a series of wind tunnel tests. It was investigated how the wind forces depend on the container configuration on the deck using a 1:450 scale model and a series of appropriate container...... are presented as nondimensional coefficients. It is concluded, that the measured forces and moment depend on the container configuration on deck, and the results may provide a general idea of how the magnitude of the wind forces is affected by a given container stacking configuration on a similar container ship....

Design tool for offshore wind farm cluster planning

DEFF Research Database (Denmark)

Hasager, Charlotte Bay; Madsen, Peter Hauge; Giebel, Gregor

2015-01-01

In the framework of the FP7 project EERA DTOC: Design Tool for Offshore wind farm Cluster, a new software supporting the planning of offshore wind farms was developed, based on state-of-the-art approaches from large scale wind potential to economic benchmarking. The model portfolio includes WAs......P, FUGA, WRF, Net-Op, LCoE model, CorWind, FarmFlow, EeFarm and grid code compliance calculations. The development is done by members from European Energy Research Alliance (EERA) and guided by several industrial partners. A commercial spin-off from the project is the tool ‘Wind & Economy’. The software...... by the software and several tests were performed. The calculations include the smoothing effect on produced energy between wind farms located in different regional wind zones and the short time scales relevant for assessing balancing power. The grid code compliance was tested for several cases and the results...

Experimental data on load test and performance parameters of a LENZ type vertical axis wind turbine in open environment condition

Directory of Open Access Journals (Sweden)

Seralathan Sivamani

2017-12-01

Full Text Available Performance and load testing data of a three bladed two stage LENZ type vertical axis wind turbine from the experiments conducted in an open environment condition at Hindustan Institute of Technology and Science, Chennai (location 23.2167°N, 72.6833°E are presented here. Low-wind velocity ranging from 2 to 11 m/s is available everywhere irrespective of climatic seasons and this data provides the support to the researchers using numerical tool to validate and develop an enhanced Lenz type design. Raw data obtained during the measurements are processed and presented in the form so as to compare with other typical outputs. The data is measured at different wind speeds prevalent in the open field condition ranging from 3 m/s to 9 m/s. Keywords: Vertical axis wind turbine, Lenz type, Performance, Two-stage, Open environment measurement

Wind energy potential in Peshawar, Pakistan

International Nuclear Information System (INIS)

Nasir, S.M.; Raza, S.M.

1994-01-01

Hourly wind data at Peshawar airport, received from the Headquarters, Pakistan Air Force, has been used to determine the diurnal variations, speed duration and speed frequency curves. The applicability of Weibull distribution is then tested over probability density function, which shows that weibull distribution fits the wind data satisfactorily and with a good precision, provided the observations of calm spells are omitted. Our analysis shows that monthly mean wind speed and wind power varies from 0.6 to 2.0 m/s and 0.2 to 4.0 wm-2, respectively, giving fair prospects for wind owe applications over the summer months. (author)

Materials for Wind Turbine Blades: An Overview

DEFF Research Database (Denmark)

Mishnaevsky, Leon; Branner, Kim; Petersen, Helga Nørgaard

2017-01-01

A short overview of composite materials for wind turbine applications is presented here. Requirements toward the wind turbine materials, loads, as well as available materials are reviewed. Apart from the traditional composites for wind turbine blades (glass fibers/epoxy matrix composites), natural...... composites, hybrid and nanoengineered composites are discussed. Manufacturing technologies for wind turbine composites, as well their testing and modelling approaches are reviewed....

Materials for Wind Turbine Blades: An Overview.

Science.gov (United States)

Mishnaevsky, Leon; Branner, Kim; Petersen, Helga Nørgaard; Beauson, Justine; McGugan, Malcolm; Sørensen, Bent F

2017-11-09

A short overview of composite materials for wind turbine applications is presented here. Requirements toward the wind turbine materials, loads, as well as available materials are reviewed. Apart from the traditional composites for wind turbine blades (glass fibers/epoxy matrix composites), natural composites, hybrid and nanoengineered composites are discussed. Manufacturing technologies for wind turbine composites, as well their testing and modelling approaches are reviewed.

Wind tunnel and CFD modelling of wind pressures on solar energy systems on flat roofs

NARCIS (Netherlands)

Bronkhorst, A.J.; Franke, J.; Geurts, C.P.W.; Bentum, van C.A.; Grepinet, F.

2010-01-01

Design of solar energy mounting systems requires more knowledge on the wind patterns around these systems. To obtain more insight in the flow patterns, which cause the pressure distributions on the solar energy systems, a wind tunnel test and Computational Fluid Dynamics analysis have been

Offshore Wind Farm Clusters - Towards new integrated Design Tool

DEFF Research Database (Denmark)

Hasager, Charlotte Bay; Réthoré, Pierre-Elouan; Peña, Alfredo

In EERA DTOC testing of existing wind farm wake models against four validation data test sets from large offshore wind farms is carried out. This includes Horns Rev-1 in the North Sea, Lillgrund in the Baltic Sea, Roedsand-2 in the Baltic Sea and from 10 large offshore wind farms in Northern Euro...

Design, fabrication, test, and evaluation of a prototype 150-foot long composite wind turbine blade

Science.gov (United States)

Gewehr, H. W.

1979-01-01

The design, fabrication, testing, and evaluation of a prototype 150 foot long composite wind turbine blade is described. The design approach and material selection, compatible with low cost fabrication methods and objectives, are highlighted. The operating characteristics of the blade during rotating and nonrotating conditions are presented. The tensile, compression, and shear properties of the blade are reported. The blade fabrication, tooling, and quality assurance are discussed.

Wind farm array wake losses

Energy Technology Data Exchange (ETDEWEB)

Baker, R.W. [Impact Weather, Washougal, WA (United States); McCarthy, E.F. [Wind Economics & Technology, Inc., Martinez, CA (United States)

1997-12-31

A wind turbine wake study was conducted in the summer of 1987 at an Altamont Pass wind electric generating facility. The wind speed deficits, turbulence, and power deficits from an array consisting of several rows of wind turbines is discussed. A total of nine different test configurations were evaluated for a downwind spacing ranging from 7 rotor diameters (RD) to 34 RD and a cross wind spacing of 1.3 RD and 2.7 RD. Wake power deficits of 15% were measured at 16 RD and power losses of a few percent were even measurable at 27 RD for the closer cross wind spacing. For several rows of turbines separated by 7-9 RD the wake zones overlapped and formed compound wakes with higher velocity deficits. The wind speed and direction turbulence in the wake was much higher than the ambient turbulence. The results from this study are compared to the findings from other similar field measurements.

Diagnostics of Electric Equipment Windings

Directory of Open Access Journals (Sweden)

I. I. Branovitsky

2007-01-01

Full Text Available The paper presents methodology and results of the investigations pertaining to study of influence of short-circuited turns on transient electrical processes in electric motor windings. Dependence of their damped speed and value of the difference signal, obtained at reciprocal subtraction of damped oscillation curves in absence and in presence of short-circuited turns, on number of turns in the tested windings. It has been determined that damped oscillation curves, immediately attributed to short-circuited turns, have peak values along temporary axis which are areas of the largest transient process sensitivity to КЗ turns.Methodology for diagnostics of single- and three-phase electric motor windings and also other electric equipment, being realized in DO-1 device, has been developed in the paper. The men­tioned device makes it possible to carry out visual comparison and quantitative analysis of damped oscillation curves in the tested windings with standard ones which are set in the device memory and their difference signals.

A Successful Small Wind Future: There Is Great Potential

Energy Technology Data Exchange (ETDEWEB)

Tegen, Suzanne

2017-05-02

Suzanne Tegen made this presentation at the 2017 Small Wind Conference in Bloomington, Minnesota. It provides an overview of DOE-sponsored small wind products, testing, and support; an example of a Regional Resource Center defending distributed wind; the recently published Distributed Wind Taxonomy; the dWind model and recent results; and other recent DOE and NREL publications related to small and distributed wind.

Small scale wind power harnessing in Colombian oil industry facilities: Wind resource and technology issues

Energy Technology Data Exchange (ETDEWEB)

Giraldo, Mauricio; Nieto, Cesar; Escudero, Ana C.; Cobos, Juan C.; Delgado, Fernando

2010-07-01

Full text: Looking to improve its national and international standing, Colombia's national oil company, Ecopetrol, has set its goal on becoming involved on the production of energy from multiple sources, most importantly, on having an important percentage of its installed capacity from renewable sources. Part of this effort entices the evaluation of wind power potential on its facilities, including production, transportation and administrative, as well as identifying those technologies most suitable for the specific conditions of an equatorial country such as Colombia. Due to the lack of adequate site information, the first step consisted in superimposing national data to the facilities map of the company; this allowed for the selection of the first set of potential sites. From this set, the terminal at Covenas-Sucre was selected taking into account not only wind resource, but ease of access and power needs, as well as having a more or less representative wind potential in comparison to the rest of the country. A weather station was then installed to monitor wind variables. Measurements taken showed high variations in wind direction, and relatively low velocity profiles, making most commercially available wind turbines difficult to implement. In light of the above, a series of iterative steps were taken, first considering a range of individual Vertical Axis Wind Turbines (VAWT), given their capacity to adapt to changing wind directions. However, wind speed variations proved to be a challenge for individual VAWT's, i.e. Darriues turbines do not work well with low wind speeds, and Savonius turbines are not efficient of high wind speeds. As a result, a combined Darrieus- Savonius VAWT was selected given the capacity to adapt to both wind regimes, while at the same time modifying the size and shape of the blades in order to adapt to the lower average wind speeds present at the site. The resulting prototype is currently under construction and is scheduled to

75 FR 23263 - Alta Wind I, LLC; Alta Wind II, LLC; Alta Wind III, LLC; Alta Wind IV, LLC; Alta Wind V, LLC...

Science.gov (United States)

2010-05-03

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL10-62-000] Alta Wind I, LLC; Alta Wind II, LLC; Alta Wind III, LLC; Alta Wind IV, LLC; Alta Wind V, LLC; Alta Wind VI, LLC; Alta Wind VII, LLC; Alta Wind VIII, LLC; Alta Windpower Development, LLC; TGP Development Company, LLC...

77 FR 29633 - Alta Wind VII, LLC, Alta Wind IX, LLC, Alta Wind X, LLC, Alta Wind XI, LLC, Alta Wind XII, LLC...

Science.gov (United States)

2012-05-18

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL12-68-000] Alta Wind VII, LLC, Alta Wind IX, LLC, Alta Wind X, LLC, Alta Wind XI, LLC, Alta Wind XII, LLC, Alta Wind XIII, LLC, Alta Wind XIV, LLC, Alta Wind XV, LLC, Alta Windpower Development, LLC, TGP Development Company, LLC...

Tree growth and soil relations at the 1925 Wind River spacing test in coast Douglas-fir.

Science.gov (United States)

Richard E. Miller; Donald L. Reukema; Harry W. Anderson

2004-01-01

The 1925 Wind River spacing test is the earliest field trial seeking to determine the most appropriate spacing for planting Douglas-fir. Spacing treatments were not replicated, although individual spacings were subsampled by two to four tree-measurement plots. Previously, greater growth occurred at the wider spacings (10 and 12 ft) than at the closer spacings (4, 5, 6...

Prevention of the wind migration of Semipalatinsk test site contaminated topsoil by inter-polymer complexes

International Nuclear Information System (INIS)

Kudaibergenov, S.E.

2010-01-01

Full text: It is well known that Semipalatinsk Test Site has been contaminated by radionuclides mainly as a result of atmospheric, aboveground and underground intensive nuclear tests during more than 40 years. Survey of residual radioactivity in the soil at ten Semipalatinsk Test Site areas showed that a great number of Plutonium-239, 240, Strontium-90 and Cesium-137 are concentrated in the depth of soil layer 0-8 cm. The residual radioactivity within the Semipalatinsk Test Site is tightly bound to the topsoil as a result of extreme heating and melting of the soils during the tests. The maximal amount of radionuclides is accumulated on the fine soil particles having 0.1-1.0 mm size. Wind erosion is responsible for suspension of contaminated soil particles in the air and further spreading of contamination far away. For instance, dust particles of diameter 0,05-0,1 mm are dropped within a couple of kilometers of the erosion site, while particles of about 0.005-0.01 mm diameter can move hundreds and thousands of kilometers. According to the results of the Institute of Radiation Safety and Ecology, Kazakhstan, in “Degelen” massive, where the intensive nuclear tests were carried out, the concentration of radionuclides in air increases for Sr-90 up to 5 times, for Pu-239,240 up to 100-250 times during the elevation of thin dust from the ground surface. In this connection agglomeration of thin dust containing radionuclides is of primary importance to protect the population from inhalation of re-suspended dust. Inter-polymer complexes are water-insoluble, moisture and gas permeable substances that form a “cobweb” on the surface of soil particles and consequently leading to formation of protective crust. Inter-polymer complexes enhance the intrusion of water into the soil, resulting in increased soil moisture to promote seed germination and plant growth. Inter-polymer complexes are also able to accumulate radionuclides via inclusion of metal ions into the Inter

Using wind tunnels to predict bird mortality in wind farms: the case of griffon vultures.

Directory of Open Access Journals (Sweden)

Manuela de Lucas

Full Text Available BACKGROUND: Wind farms have shown a spectacular growth during the last 15 years. Avian mortality through collision with moving rotor blades is well-known as one of the main adverse impacts of wind farms. In Spain, the griffon vulture incurs the highest mortality rates in wind farms. METHODOLOGY/PRINCIPAL FINDINGS: As far as we know, this study is the first attempt to predict flight trajectories of birds in order to foresee potentially dangerous areas for wind farm development. We analyse topography and wind flows in relation to flight paths of griffon vultures, using a scaled model of the wind farm area in an aerodynamic wind tunnel, and test the difference between the observed flight paths of griffon vultures and the predominant wind flows. Different wind currents for each wind direction in the aerodynamic model were observed. Simulations of wind flows in a wind tunnel were compared with observed flight paths of griffon vultures. No statistical differences were detected between the observed flight trajectories of griffon vultures and the wind passages observed in our wind tunnel model. A significant correlation was found between dead vultures predicted proportion of vultures crossing those cells according to the aerodynamic model. CONCLUSIONS: Griffon vulture flight routes matched the predominant wind flows in the area (i.e. they followed the routes where less flight effort was needed. We suggest using these kinds of simulations to predict flight paths over complex terrains can inform the location of wind turbines and thereby reduce soaring bird mortality.

Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing.

Science.gov (United States)

Zavadsky, Andrey; Shemer, Lev

2018-02-13

This manuscript describes an experimental procedure that allows obtaining diverse quantitative information on temporal and spatial evolution of water waves excited by time-dependent and steady wind forcing. Capacitance-type wave gauge and Laser Slope Gauge (LSG) are used to measure instantaneous water surface elevation and two components of the instantaneous surface slope at a number of locations along the test section of a wind-wave facility. The computer-controlled blower provides airflow over the water in the tank whose rate can vary in time. In the present experiments, the wind speed in the test section initially increases quickly from rest to the set value. It is then kept constant for the prescribed duration; finally, the airflow is shut down. At the beginning of each experimental run, the water surface is calm and there is no wind. Operation of the blower is initiated simultaneously with the acquisition of data provided by all sensors by a computer; data acquisition continues until the waves in the tank fully decay. Multiple independent runs performed under identical forcing conditions allow determining statistically reliable ensemble-averaged characteristic parameters that quantitatively describe wind-waves' variation in time for the initial development stage as a function of fetch. The procedure also allows characterizing the spatial evolution of the wave field under steady wind forcing, as well as decay of waves in time, once the wind is shut down, as a function of fetch.

Noise and noise disturbances from wind power plants - Tests with interactive control of sound parameters for more comfortable and less perceptible sounds

International Nuclear Information System (INIS)

Persson-Waye, K.; Oehrstroem, E.; Bjoerkman, M.; Agge, A.

2001-12-01

In experimental pilot studies, a methodology has been worked out for interactively varying sound parameters in wind power plants. In the tests, 24 persons varied the center frequency of different band-widths, the frequency of a sinus-tone and the amplitude-modulation of a sinus-tone in order to create as comfortable a sound as possible. The variations build on the noise from the two wind turbines Bonus and Wind World. The variations were performed with a constant dba level. The results showed that the majority preferred a low-frequency tone (94 Hz and 115 Hz for Wind World and Bonus, respectively). The mean of the most comfortable amplitude-modulation varied between 18 and 22 Hz, depending on the ground frequency. The mean of the center-frequency for the different band-widths varied from 785 to 1104 Hz. In order to study the influence of the wind velocity on the acoustic character of the noise, a long-time measurement program has been performed. A remotely controlled system has been developed, where wind velocity, wind direction, temperature and humidity are registered simultaneously with the noise. Long-time registrations have been performed for four different wing turbines

Application of Computational Fluid Dynamics (CFD) in transonic wind-tunnel/flight-test correlation

Science.gov (United States)

Murman, E. M.

1982-01-01

The capability for calculating transonic flows for realistic configurations and conditions is discussed. Various phenomena which were modeled are shown to have the same order of magnitude on the influence of predicted results. It is concluded that CFD can make the following contributions to the task of correlating wind tunnel and flight test data: some effects of geometry differences and aeroelastic distortion can be predicted; tunnel wall effects can be assessed and corrected for; and the effects of model support systems and free stream nonuniformities can be modeled.

Joint excitation synchronization characteristics of fatigue test for offshore wind turbine blade