Download or read book Experimental Investigation Into the Effectiveness of a Microtab Aerodynamic Load Control System written by Jonathon Paul Baker and published by . This book was released on 2005 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Active Load Control Using Microtabs written by Dora Te-Lun Yen and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Micro-electro-mechanical (MEM) translational tabs are introduced for enhancing and controlling the aerodynamic loading on lifting surfaces. These microtabs are mounted near the trailing edge of lifting surfaces, retract and extend approximately normal to the surface and have a maximum deployment height on the order of the boundary-layer thickness. Deployment of the device effectively modifies the camber distribution of the lifting surface and hence, the lift generated. The effect of the microtabs on lift is shown to be as powerful as conventional control surfaces with lift changes of 30%-50% in the linear range of the lift curve using a tab with a height of 1% of airfoil chord placed at 5% of chord upstream of the trailing edge on the lower surface. A multi-disciplinary approach incorporating aspects of experimental and computational aerodynamics, mechanical design and microfabrication techniques has been taken to develop and test a "proof of concept" model. Flow simulations, using a Reynolds-averaged Navier Stokes solver, have been conducted to optimize the size and placement of the devices based on trailing edge volume constraints. Numerical and experimental wind tunnel results are in good agreement, and both confirm that these micro-scale devices create macro-scale changes in aerodynamic loading. Application of this rather simple but innovative lift control system based on microfabrication techniques introduces a robust, dynamic control device and will allow for the miniaturization of conventional high lift and control systems. The result is a significant reduction in typical control system weight, complexity and cost. Also due to the minute size of these tabs, their activation and response times are much faster than that of conventional trailing edge devices. The 'proof of concept' tab design, fabrication techniques, computational and experimental setup, and test results using a representative airfoil are presented in this research.

Download or read book Unsteady Computational Investigations of Deploying Load control Microtabs written by Raymond Chow and published by . This book was released on 2006 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Active Load Control Techniques for Wind Turbines Focusing on Mechanical Design of a Microtab System written by Scott Jeremy Johnson and published by . This book was released on 2008 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computational Investigation on the Application of Using Microjets as Active Aerodynamic Load Control for Wind Turbines written by Myra Louise Blaylock and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A fast, efficient way to control loads on industrial scale turbines is important for the growth of the wind industry. Active Aerodynamic Load Control (AALC) is one area which addresses this need. In particular, microjets, which are pneumatic jets located at the trailing edge of a wind turbine blade and blow perpendicular to the blade surface, are a possible AALC candidate. First, the Computational Fluid Dynamics (CFD) solver OVERFLOW is used to explore the effects of a microjet on lift, drag, and pitching moment. Then the interaction between an aerodynamic disturbance and an airfoil equipped with a microjet is modeled. The object of this dissertation is to investigate microtabs as viable AALC devices by presenting their aerodynamic properties and testing whether a proportional-integral (PI) controlled jets can alleviate loads caused by wind gusts. The use of CFD to simulate a microjet is validated by comparing the results to both previous experiments found in the literature as well as wind tunnel tests completed at UC Davis. The aerodynamic effectiveness of the jet is investigated as a function of various parameters such as Reynolds number, angle of attack, and the momentum coefficient of the jet. The effects of the microjet are found to be very similar to another AALC device, the microtab. An aerodynamic disturbance is simulated, and a control algorithm which is incorporated into the OVERFLOW code is used to activate the microjet, thus reducing the change of the blade load due to the gust. Finally, a more realistic model is made by adding both a linear and a torsional spring and damper to represent the blade movement. This two-degree of freedom system shows that during a gust the vertical blade movement is reduced when the microjets are activated. Microjets are found to work well to alleviate the changes in aerodynamic loads felt by the airfoil, and are therefore a good candidate for a practical AALC device. However, further investigation is needed in the areas of aeroacoustics, system energy requirements, and logistics of implementation.

Download or read book Computational Design and Analysis of a Microtab Based Aerodynamic Loads Control System for Lifting Surfaces written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents a computational design and analysis of a microtab based aerodynamic loads control system. The computational methods applied in the development of this concept solve the governing Reynolds-averaged Navier-Stokes equations on structured, overset grids. The application of these methods to simulate the flows over lifting surfaces including the tabs has been paramount in the development of these devices. The numerical results demonstrate the effectiveness of the microtab and that it is possible to carry out a sensitivity analysis on the positioning and sizing of the tabs before they are implemented in successfully controlling the aerodynamic loads.

Download or read book Computational Design and Analysis of a Micro Tab Based Aerodynamic Loads Control System for Lifting Surfaces written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A computational design and analysis of a microtab based aerodynamic loads control system is presented. The microtab consists of a small tab that emerges from a wing approximately perpendicular to its surface in the vicinity of its trailing edge. Tab deployment on the upper side of the wing causes a decrease in the lift generation whereas deployment on the pressure side causes an increase. The computational methods applied in the development of this concept solve the governing Reynolds-averaged Navier-Stokes equations on structured, overset grids. The application of these methods to simulate the flows over lifting surface including the tabs has been paramount in the development of these devices. The numerical results demonstrate the effectiveness of the microtab and that it is possible to carry out a sensitivity analysis on the positioning and sizing of the tabs before they are implemented in successfully controlling the aerodynamic loads.

Download or read book Verti flite written by and published by . This book was released on 2002 with total page 868 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Investigation Into the Aerodynamic Performance of Both Rigid and Flexible Wing Structured Micro Air Vehicles written by Anthony M. DeLuca and published by . This book was released on 2004-03-01 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Air Force Research Lab, Munitions Directorate, Eglin Air Force Base, Florida has designed a man-portable carbon-fiber Micro-Air-Vehicle (MA V) used for on-the-spot surveillance by Special Operations Forces (SOF) for enemy reconnaissance as well as post-strike Battle Damage Assessment (BDA).The main goals of this experiment are: 1) characterize the flow quality of the new AFIT 3' x 3' wind tunnel and 2) determine the aerodynamic performance characteristics of the 24" span, 6" chord flexible and rigid wing MA V s. The turbulent intensity of the wind tunnel was approximately 2%. Both MA Vs had an average lift slope within 3.5% of the theoretical value. Flexible wings deformed in response to perturbations in local flow field conditions, promulgating the delay of wing stall by nearly double. Aeroelastic effects begin to dominate low speed, laminar Reynolds number effects at tunnel velocities greater than 30 miles per hour. The flexible wing MA V displayed static stability in all three principal control axes (Pitch, Roll, Yaw), while the rigid MA V was not definitively stable in any axis. All flexible wing control surface configurations resulted in predictable and consistent performance between -10 and + 10 elevon deflection. Reponses declined steadily after :+ or -10 showing dramatic direction changes.

Download or read book Active Load Control Using Microtabs written by Dora Te-Lun Yen and published by . This book was released on 2001 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wind Energy Systems written by Mario Garcia-Sanz and published by CRC Press. This book was released on 2012-02-02 with total page 635 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presenting the latest developments in the field, Wind Energy Systems: Control Engineering Design offers a novel take on advanced control engineering design techniques for wind turbine applications. The book introduces concurrent quantitative engineering techniques for the design of highly efficient and reliable controllers, which can be used to solve the most critical problems of multi-megawatt wind energy systems. This book is based on the authors’ experience during the last two decades designing commercial multi-megawatt wind turbines and control systems for industry leaders, including NASA and the European Space Agency. This work is their response to the urgent need for a truly reliable concurrent engineering methodology for the design of advanced control systems. Outlining a roadmap for such a coordinated architecture, the authors consider the links between all aspects of a multi-megawatt wind energy project, in which the wind turbine and the control system must be cooperatively designed to achieve an optimized, reliable, and successful system. Look inside for links to a free download of QFTCT—a new interactive CAD tool for QFT controller design with MATLAB® that the authors developed with the European Space Agency. The textbook’s big-picture insights can help students and practicing engineers control and optimize a wind energy system, in which large, flexible, aerodynamic structures are connected to a demanding variable electrical grid and work automatically under very turbulent and unpredictable environmental conditions. The book covers topics including robust QFT control, aerodynamics, mechanical and electrical dynamic modeling, economics, reliability, and efficiency. It also addresses standards, certification, implementation, grid integration, and power quality, as well as environmental and maintenance issues. To reinforce understanding, the authors present real examples of experimentation with commercial multi-megawatt direct-drive wind turbines, as well as on-shore, offshore, floating, and airborne wind turbine applications. They also offer a unique in-depth exploration of the quantitative feedback theory (QFT)—a proven, successful robust control technique for real-world applications—as well as advanced switching control techniques that help engineers exceed classical linear limitations.

Download or read book Adaptive Structures and Material Systems written by and published by . This book was released on 2002 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aerodynamic Analysis of Blunt Trailing Edge Airfoils a Micro based Load Control System written by Kevin James Standish and published by . This book was released on 2003 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanics And Architectural Design Proceedings Of 2016 International Conference written by Shi-hong Zhang and published by World Scientific. This book was released on 2016-11-24 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2016 International Conference on Mechanics and Architectural Design (MAD2016) were held in Suzhou, Jiangsu, China, 14 - 15 May 2016. The main objective of this conference is to provide a platform for researchers, academics and industrial professionals to present their research findings in the fields of Architecture, Mechanical and Civil Engineering.This proceedings consists of 90 articles selected after peer-review. It consists of 6 articles in Mechanics, and 84 articles covering research and development in Civil Engineering; addressing issues in building architecture and structure. Most of these projects were funded by the Chinese research agencies.

Download or read book ASME Wind Energy Symposium written by and published by . This book was released on 2001 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Harvesting and Energy Efficiency written by Nicu Bizon and published by Springer. This book was released on 2017-03-09 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents basic and advanced concepts for energy harvesting and energy efficiency, as well as related technologies, methods, and their applications. The book provides up-to-date knowledge and discusses the state-of-the-art equipment and methods used for energy harvesting and energy efficiency, combining theory and practical applications. Containing over 200 illustrations and problems and solutions, the book begins with overview chapters on the status quo in this field. Subsequent chapters introduce readers to advanced concepts and methods. In turn, the final part of the book is dedicated to technical strategies, efficient methods and applications in the field of energy efficiency, which also makes it of interest to technicians in industry. The book tackles problems commonly encountered using basic methods of energy harvesting and energy efficiency, and proposes advanced methods to resolve these issues. All the methods proposed have been validated through simulation and experimental results. These “hot topics” will continue to be of interest to scientists and engineers in future decades and will provide challenges to researchers around the globe as issues of climate change and changing energy policies become more pressing. Here, readers will find all the basic and advanced concepts they need. As such, it offers a valuable, comprehensive guide for all students and practicing engineers who wishing to learn about and work in these fields.

Download or read book Wind Turbines written by Abdel Ghani Aissaoui and published by BoD – Books on Demand. This book was released on 2016-07-27 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Renewable energies constitute excellent solutions to both the increase of energy consumption and environment problems. Among these energies, wind energy is very interesting. Wind energy is the subject of advanced research. In the development of wind turbine, the design of its different structures is very important. It will ensure: the robustness of the system, the energy efficiency, the optimal cost and the high reliability. The use of advanced control technology and new technology products allows bringing the wind energy conversion system in its optimal operating mode. Different strategies of control can be applied on generators, systems relating to blades, etc. in order to extract maximal power from the wind. The goal of this book is to present recent works on design, control and applications in wind energy conversion systems.