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Proof Of Concept Test For Dual Axis Resonant Phase Locked Excitation Phlex Fatigue Testing Method For Wind Turbine Blades
Download Proof Of Concept Test For Dual Axis Resonant Phase Locked Excitation Phlex Fatigue Testing Method For Wind Turbine Blades full books in PDF, epub, and Kindle. Read online Proof Of Concept Test For Dual Axis Resonant Phase Locked Excitation Phlex Fatigue Testing Method For Wind Turbine Blades ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Proof of Concept Test for Dual-axis Resonant Phase-Locked Excitation (PhLEX) Fatigue Testing Method for Wind Turbine Blades by : Jenna Austin Beckwith
Download or read book Proof of Concept Test for Dual-axis Resonant Phase-Locked Excitation (PhLEX) Fatigue Testing Method for Wind Turbine Blades written by Jenna Austin Beckwith and published by . This book was released on 2014 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: The PhLEX proof-of-concept test set-up and the results and conclusions of the proof-of-concept test are presented in this thesis.
Book Synopsis The Development of a Phase Locked Excitation Testing Method for Full-scale Wind Turbine Blades by : Waleed F. Gowharji
Download or read book The Development of a Phase Locked Excitation Testing Method for Full-scale Wind Turbine Blades written by Waleed F. Gowharji and published by . This book was released on 2011 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Historically, fatigue testing has been performed by utilizing force displacement systems. These systems do not allow for the load phase angle to be controlled, which leads to inaccurate loading distributions, when compared to actual field gathered data. The PhLEX (Phase Locked Excitation System) testing method outlined herein utilizes resonant excitation system in order to reduce energy requirements, decrease test duration and improve overall loading distributed."--Leaf iii.
Book Synopsis New Method for Dual-Axis Fatigue Testing of Large Wind Turbine Blades Using Resonance Excitation and Spectral Loading - Scholar's Choice Edition by : National Renewable Energy Laboratory (Nr
Download or read book New Method for Dual-Axis Fatigue Testing of Large Wind Turbine Blades Using Resonance Excitation and Spectral Loading - Scholar's Choice Edition written by National Renewable Energy Laboratory (Nr and published by Scholar's Choice. This book was released on 2015-02-16 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Book Synopsis New Method for Dual-Axis Fatigue Testing of Large Wind Turbine Blades Using Resonance Excitation and Spectral Loading by :
Download or read book New Method for Dual-Axis Fatigue Testing of Large Wind Turbine Blades Using Resonance Excitation and Spectral Loading written by and published by . This book was released on 2004 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis A New Method for Dual-axis Fatigue Testing of Large Wind Turbine Blades Using Resonance Excitation and Spectral Loading by : Darris L. White
Download or read book A New Method for Dual-axis Fatigue Testing of Large Wind Turbine Blades Using Resonance Excitation and Spectral Loading written by Darris L. White and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Evaluation of the New B-REX Fatigue Testing System for Multi-Megawatt Wind Turbine Blades by :
Download or read book Evaluation of the New B-REX Fatigue Testing System for Multi-Megawatt Wind Turbine Blades written by and published by . This book was released on 2004 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: The National Renewable Energy Laboratory (NREL) recently developed a new hybrid fatigue testing system called the Blade Resonance Excitation (B-REX) test system. The new system uses 65% less energy to test large wind turbine blades in half the time of NREL's dual-axis forced-displacement test method with lower equipment and operating costs. The B-REX is a dual-axis test system that combines resonance excitation with forced hydraulic loading to reduce the total test time required while representing the operating strains on the critical inboard blade stations more accurately than a single-axis test system. The analysis and testing required to fully implement the B-REX was significant. To control unanticipated blade motion and vibrations caused by dynamic coupling between the flap, lead-lag, and torsional directions, we needed to incorporate additional test hardware and control software. We evaluated the B-REX test system under stable operating conditions using a combination of various sensors. We then compared our results with results from the same blade, tested previously using NREL's dual-axis forced-displacement test method. Experimental results indicate that strain levels produced by the B-REX system accurately replicated the forced-displacement method. This paper describes the challenges we encountered while developing the new blade fatigue test system and the experimental results that validate its accuracy.
Book Synopsis Evaluation of the New B-REX Fatigue Testing System for Multi-megawatt Wind Turbine Blades by : Darris White
Download or read book Evaluation of the New B-REX Fatigue Testing System for Multi-megawatt Wind Turbine Blades written by Darris White and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The National Renewable Energy Laboratory (NREL) recently developed a new hybrid fatigue testing system called the Blade Resonance Excitation (B-REX) test system. The new system uses 65% less energy to test large wind turbine blades in half the time of NREL's dual-axis forced-displacement test method with lower equipment and operating costs. The B-REX is a dual-axis test system that combines resonance excitation with forced hydraulic loading to reduce the total test time required while representing the operating strains on the critical inboard blade stations more accurately than a single-axis test system. The analysis and testing required to fully implement the B-REX was significant. To control unanticipated blade motion and vibrations caused by dynamic coupling between the flap, lead-lag, and torsional directions, we needed to incorporate additional test hardware and control software. We evaluated the B-REX test system under stable operating conditions using a combination of various sensors. We then compared our results with results from the same blade, tested previously using NREL's dual-axis forced-displacement test method. Experimental results indicate that strain levels produced by the B-REX system accurately replicated the forced-displacement method. This paper describes the challenges we encountered while developing the new blade fatigue test system and the experimental results that validate its accuracy.
Book Synopsis Wind Turbine Blade Testing System using Base Excitation by :
Download or read book Wind Turbine Blade Testing System using Base Excitation written by and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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) ispivotally 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 infirst and second transverse directions. The test article (404) responds to shaking of its base (406) by oscillating in two, transverse directions (505, 507).
Book Synopsis Biaxial Dynamic Fatigue Tests of Wind Turbine Blades by : Falko Bürkner
Download or read book Biaxial Dynamic Fatigue Tests of Wind Turbine Blades written by Falko Bürkner and published by Fraunhofer Verlag. This book was released on 2021-04-09 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Testing rotor blades of wind turbines is essential to mitigate financial risks caused by serial damages. Present day uniaxial dynamic tests are time consuming and often inaccurate regarding the applied loading. This thesis proposes a faster fatigue test method by loading the two primary directions at the same time. In addition, a more realistic test, compared to uniaxial tests, is accomplished by loading larger areas of the blade cross-sections. To achieve this, an elliptical biaxial dynamic excitation is used. To fulfill the industry requirement for cost effective tests, a relatively simple test setup was developed, still achieving an elliptical dynamic excitation of the rotor blade. Two methods for an accurate determination of the applied loadings for dynamic fatigue tests are described. These calibration tests use easily measured values and simple analysis to achieve accurate test load measurements in a cost-effective way.
Book Synopsis Dual-axis Resonance Testing of Wind Turbine Blades by :
Download or read book Dual-axis Resonance Testing of Wind Turbine Blades written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Implementation of a Biaxial Resonant Fatigue Test Method on a Large Wind Turbine Blade by :
Download or read book Implementation of a Biaxial Resonant Fatigue Test Method on a Large Wind Turbine Blade written by and published by . This book was released on 2014 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: A biaxial resonant test method was utilized to simultaneously fatigue test a wind turbine blade in the flap and edge (lead-lag) direction. Biaxial resonant blade fatigue testing is an accelerated life test method utilizing oscillating masses on the blade; each mass is independently oscillated at the respective flap and edge blade resonant frequency. The flap and edge resonant frequency were not controlled, nor were they constant for this demonstrated test method. This biaxial resonant test method presented surmountable challenges in test setup simulation, control and data processing. Biaxial resonant testing has the potential to complete test projects faster than single-axis testing. The load modulation during a biaxial resonant test may necessitate periodic load application above targets or higher applied test cycles.
Book Synopsis Implementation of a biaxial resonant fatigue test method on a large wind turbine blade by : D. Snowberg
Download or read book Implementation of a biaxial resonant fatigue test method on a large wind turbine blade written by D. Snowberg and published by . This book was released on 2014 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Implementation of a Two-Axis Servo-Hydraulic System for Full-Scale Fatigue Testing of Wind Turbine Blades by :
Download or read book Implementation of a Two-Axis Servo-Hydraulic System for Full-Scale Fatigue Testing of Wind Turbine Blades written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, the blade fatigue testing capabilities at NREL were upgraded from single-axis to two-axis loading. To implement this, several practical challenges were addressed, as hardware complexity increased dramatically with two actuators applying the loads at right angles to each other. A custom bellcrank was designed and implemented to minimize the load angle errors and to prevent actuator side loading. The control system was upgraded to accept load and displacement feedback from two actuators. The inherent long strokes uniquely associated with wind turbine blade-tests required substantial real-time corrections for both the control and data systems. A custom data acquisition and control system was developed using a National Instruments LabVIEW platform that interfaces with proprietary servo-hydraulic software developed by MTS Corporation. Before testing, the program is run under quasi-static (slow speed) conditions and iterates to determine the correct operational control parameters for the controller, taking into consideration geometry, test speed, and phase angle errors between the two actuators. Comparisons are made between single-axis and two-axis test loads using actual test load data and load uncertainties are qualitatively described. To date, two fatigue tests have been completed and another is currently ongoing using NREL's two-axis capability.
Book Synopsis Wind Turbine Blade Testing System Using Base Excitation by :
Download or read book Wind Turbine Blade Testing System Using Base Excitation written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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).
Book Synopsis Determining Equivalent Damage Loading for Full-scale Wind Turbine Blade Fatigue Tests by :
Download or read book Determining Equivalent Damage Loading for Full-scale Wind Turbine Blade Fatigue Tests written by and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes a simplified method for converting wind turbine rotor design loads into equivalent-damage, constant-amplitude loads and load ratios for both flap and lead-lag directions. It is an iterative method that was developed at the National Renewable Energy Laboratory (NREL) using Palmgren-Miner's linear damage principles. The general method is unique because it does not presume that any information about the materials or blade structural properties is precisely known. According to this method, the loads are never converted to stresses. Instead, a family of M-N curves (moment vs. cycles) is defined with reasonable boundaries for load-amplitude and slope. An optimization program iterates and converges on the constant amplitude test load and load ratio that minimizes the sensitivity to the range of M-N curves for each blade section. The authors constrained the general method to match the NedWind 25 design condition for the Standards, Measurements, and Testing (SMT) blade testing pro gram. SMT participants agreed to use the fixed S-N slope of m = 10 from the original design to produce consistent test-loads among the laboratories. Unconstrained, the general method suggests that slightly higher test loads should be used for the NedWind 25 blade design spectrum. NedWind 25 blade test loads were computed for lead-lag and flap under single-axis and two-axis loading.
Book Synopsis National Wind Tecnology Center Provides Dual Axis Resonant Blade Testing by :
Download or read book National Wind Tecnology Center Provides Dual Axis Resonant Blade Testing written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: NREL's Structural Testing Laboratory at the National Wind Technology Center (NWTC) provides experimental laboratories, computer facilities for analytical work, space for assembling components and turbines for atmospheric testing as well as office space for industry researchers. Fort Felker, center director at the NWTC, discusses NREL's state-of-the-art structural testing capabilities and shows a flapwise and edgewise blade test in progress.
Book Synopsis Characterization of a Mobile Oscillatory Fatigue Operator for Wind Turbine Blade Testing by :
Download or read book Characterization of a Mobile Oscillatory Fatigue Operator for Wind Turbine Blade Testing written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Laboratory testing of wind turbine blades is required to meet wind turbine design standards, reduce machine cost, and reduce the technical and fi nancial risks of deploying mass-produced wind turbine models. Fatigue testing at the National Wind Technology Center (NWTC) is currently conducted using Universal Resonance Excitation (UREX) technology. In a UREX test, the blade is mounted to a rigid stand and hydraulic exciters mounted to the blade are used to excite the blade to its resonant frequency. A drawback to UREX technology is that mounting hydraulic systems to the blade is diffi cult and requires a relatively long set-up period. An alternative testing technology called the Mobile Oscillatory Fatigue Operator (MOFO) has been analyzed. The MOFO uses an oscillating blade test-stand rather than a rigid stand, avoiding the need to place hydraulic systems on the blade. The MOFO will be demonstrated by converting an existing test-stand at the NWTC to an oscillating stand that can test blades up to 25 m in length. To obtain the loads necessary to design the MOFO, the system motion is modeled using rigid body and lumped mass dynamics models. Preliminary modeling indicates the existing stand can be converted to a MOFO relatively easily. However, the blade dynamic models suggest that blade bending moment distributions are signifi cantly different for UREX and MOFO testing; more sophisticated models are required to assess the implication of this difference on the accuracy of the test.
