Download or read book Numerical Simulation of The Aerodynamic Performance of Horizontal Axis Wind Turbine HAWT Blades written by 李孟賢 and published by . This book was released on 2014 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation of the Aerodynamic Performance of an H rotor written by Yan Chen and published by . This book was released on 2011 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vertical axis wind turbines (VAWTs) are devices to convert wind energy into electricity. Unlike horizontal axis wind turbines (HAWT) where the main rotor shaft is set horizontally, VAWTs use vertical rotor shaft. Unlike HAWTs, VAWTs can be effectively used in urban environment where flow is characterized with unsteadiness and turbulence. The efficiency of the VA WTs highly depends on the aerodynamics of the wind blades. In this thesis we study the aerodynamics of the H-rotor, one type of VAWTs using computational fluid dynamics methods. Two different approaches are used in this study. One is based on direct numerical simulation (DNS) method and another is based on Reynolds averaged Navier-Stoke (RANS) model. For DNS study we solve the incompressible Navier-Stokes equations with a CFD package, OVERTURE. An overlapping moving grids technique is employed to handle the rotation of the wind turbine. For RANS simulation we used a commercial CFD package ANSYS-Fluent. The sliding mesh model of ANSYS-Fluent is applied to evaluate unsteady interaction between the stationary and rotating components. Our simulation shows that the DNS cannot correctly predict the power coefficient due to the lack of grid resolution at high Reynolds numbers. The RANS simulation results closely match the experimental data and RANS provides a way to study wind turbine aerodynamics in an efficient and reliable manner. Our simulation shows that the rotor with NACA0015 blade section obtains a maximum power coefficient of 0.16 at tip speed ratio of 2.5 for mean wind velocity of 3.9m/s. By replacing the blade section with NACA0022 airfoil profile, the maximum power coefficient of the rotor can be improved to 0.21 at tip speed ratio of 2.5 in the same wind conditions.
Download or read book Horizontal Axis Wind Turbine Blade Design and Its Aerodynamic Performance Analysis Using Improved Blade Element Momentum Theory Wind Tunnel Measurement and Numerical Simulation written by 白啟正 and published by . This book was released on 2013 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Numerical Investigation of Aerodynamic Performance for Vertical Axis Wind Turbine Models with Various Blade Designs written by Travis E. Salyers and published by . This book was released on 2016 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Author's abstract: The demand for wind energy as a renewable source is rising substantially. A growing interest exists in utilizing potential energy conversion applications in areas with less powerful and less consistent wind conditions. In these areas, vertical-axis wind turbines (VAWTs) possess several advantages over the conventional horizontal-axis type. Savonius turbines are drag-based rotors which operate due to a pressure difference between the advancing and retreating blades. These turbines are simpler in design, less expensive to install, non-dependent of wind direction, and more efficient in lower wind speeds. In the present study, six different rotor designs with equal swept areas are analyzed with wind tunnel testing and numerical simulations. These models include a traditional Savonius with 2 blades, “CC” model, “QM” model, and 90 degree helical twist models with 2, 3, and 4 blades. The models were designed using the CAD software SolidWorks. Due to the complex geometry of the blades, the physical models were then 3D printed for experimental testing. Subsonic, open-type wind tunnel testing was used for measuring RPM and reactional torque over a range of wind speeds. For the numerical approach, ANSYS Fluent simulations were used for analyzing aerodynamic performance by utilizing moving reference frame and sliding mesh model techniques. For the models with helical twist, the cross-sections of the blades varies in the Y-direction. Because of this, a 3-dimensional and transient method was used for accurately solving torque and power coefficients. The 5 new rotor geometries included in the study create a center of pressure further from the axis of rotation causing greater torque on the turbine shaft, compared to the traditional Savonius turbine. The CC and QM cross-sections reduce the total range of negative torque on the blades by 20 degrees, compared to the traditional Savonius model. Helical designs better spread the applied torque over a complete revolution resulting in positive torque over all operational angles. Helical models with 2 and 3 blades have the best self-starting capability in low wind speeds. Under no generator loading, Helical3 begins rotation of 35 RPM at just 1.4 m/s wind velocity. The highest power coefficient in the study is achieved, both experimentally and numerically, by the helical VAWT with 2 blades. Averaged over one full rotation, a maximum power coefficient of 0.14 is observed with the Helical2 model at tip-speed ratio of 0.475.
Download or read book Aerodynamics of Wind Turbines 2nd edition written by Martin O. L. Hansen and published by Routledge. This book was released on 2013-05-13 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its second edition, it has been entirely updated and substantially extended to reflect advances in technology, research into rotor aerodynamics and the structural response of the wind turbine structure. Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element Momentum method is also covered, as are eigenmodes and the dynamic behaviour of a turbine. The new material includes a description of the effects of the dynamics and how this can be modelled in an ?aeroelastic code?, which is widely used in the design and verification of modern wind turbines. Further, the description of how to calculate the vibration of the whole construction, as well as the time varying loads, has been substantially updated.
Download or read book Proceedings of the 7th International Conference on Advances in Energy Research written by Manaswita Bose and published by Springer Nature. This book was released on 2020-10-17 with total page 1639 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents selected papers from the 7th International Conference on Advances in Energy Research (ICAER 2019), providing a comprehensive coverage encompassing all fields and aspects of energy in terms of generation, storage, and distribution. Themes such as optimization of energy systems, energy efficiency, economics, management, and policy, and the interlinkages between energy and environment are included. The contents of this book will be of use to researchers and policy makers alike.
Download or read book Flexibility and Efficiency Enhancements for Constrained Global Design Optimization with Kriging Approximations written by Michael James Sasena and published by . This book was released on 2002 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation of Morphing Blades for Vertical Axis WInd Turbines written by Jennifer Tan and published by . This book was released on 2017 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: The simulation of flow through vertical axis wind turbine (VAWT) is characterized by unsteady flow where the blade experiences varying angles of attack and Reynolds number as it completes a cycle. Therefore, the lift generated also varies as a function of its rotational position relative to the incoming freestream velocity. In order to improve the performance of these turbines the blade can take advantage of smart materials developed for control surface actuation. The aim of this paper is to investigate the effect of morphing blades on the aerodynamic performance of the turbine blades. The study uses commercial software Ansys Fluent pressure-based solver to investigate the flow past the turbine blades by solving the 2D Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations. In order to simulate the morphing blade for VAWT, a sliding mesh method is used to simulate the VAWT rotation while a user-defined function (UDF) is written for the blade morphing flexure motion. This entails the use of dynamic mesh smoothing to prevent the mesh from having negative cell volumes. Although the dynamic mesh strategy has been successful in preserving the cell quality, it has been shown that the proposed method of simulating the morphing blade on VAWT is inadequate due to unphysical solutions. Finally, the effect of morphing the blade is tested on a static airfoil case instead, where it is shown that stall is alleviated by morphing the blade trailing edge.
Download or read book Numerical Simulation Advanced Techniques for Science and Engineering written by Ali Soofastaei and published by BoD – Books on Demand. This book was released on 2023-11-15 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical simulation is a powerful tool used in various fields of science and engineering to model complex systems and predict their behavior. It involves developing mathematical models that describe the behavior of a system and using computer algorithms to solve these models numerically. By doing so, researchers and engineers can study the behavior of a system in detail, which may only be possible with analytical methods. Numerical simulation has many advantages over traditional analytical methods. It allows researchers and engineers to study complex systems’ behavior in detail and predict their behavior in different scenarios. It also allows for the optimization of systems and the identification of design flaws before they are built. However, numerical simulation has its limitations. It requires significant computational resources, and the accuracy of the results depends on the quality of the mathematical models and the discretization methods used. Nevertheless, numerical simulation remains a valuable tool in many fields and its importance is likely to grow as computational resources become more powerful and widely available. Numerical simulation is widely used in physics, engineering, computer science, and mathematics. In physics, for example, numerical simulation is used to study the behavior of complex systems such as weather patterns, fluid dynamics, and particle interactions. In engineering, it is used to design and optimize systems such as aircraft, cars, and buildings. In computer science, numerical simulation models and optimization algorithms and data structures. In mathematics, it is used to study complex mathematical models and to solve complex equations. This book familiarizes readers with the practical application of the numerical simulation technique to solve complex analytical problems in different industries and sciences.
Download or read book Numerical Modeling of Wind Turbine Aerodynamics written by and published by . This book was released on 2011 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: A three-dimensional numerical method was used to validate the aerodynamic performance of a two-bladed wind turbine. The method is based on ideal fluid mechanics (e.g., potential flow) and the simpler governing equations require only a few minutes of computational time. The spiral wake is modeled as a vortex sheet, providing the induced velocity effects without vortex decay, a problem inherent to some other numerical methods. Also, for an efficient wind turbine design, flow-separation on the blades must be avoided. Therefore, for such attached flow problems, the current inviscid-flow model is not only faster but provides satisfactory results. Calculated torque, axial force, and efficiency values compared well with similar data published by NREL (National Research Energy Laboratory) for a two-bladed wind turbine. Blade-section pressure coefficients were also calculated and presented for this baseline design and areas where flow separation is possible were identified. Based on these observations, a modified airfoil section was proposed, using the same blade planform geometry. Computed results and comparisons with the baseline wind turbine geometry indicate that improvements in both power and efficiency are possible (in spite of the baseline being very well designed). The method presented here paves the way for a more comprehensive redesign modification where both blade shape, twist and airfoil section can be improved. This approach can enhance performance over a wider range of wind turbine geometry and wind speed conditions.
Download or read book Aerodynamic Comparison of a Swept Edge and Straight Edge Wind Turbine Blade Through Numerical Simulation written by Ryan Malloy and published by . This book was released on 2009 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wind Turbine Design written by Ion Paraschivoiu and published by Presses inter Polytechnique. This book was released on 2002 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: The depletion of global fossil fuel reserves combined with mounting environmental concerns has served to focus attention on the development of ecologically compatible and renewable alternative sources of energy. Wind energy, with its impressive growth rate of 40% over the last five years, is the fastest growing alternate source of energy in the world since its purely economic potential is complemented by its great positive environmental impact. The wind turbine, whether it may be a Horizontal Axis Wind Turbine (HAWT) or a Vertical Axis Wind Turbine (VAWT), offers a practical way to convert the wind energy into electrical or mechanical energy. Although this book focuses on the aerodynamic design and performance of VAWTs based on the Darrieus concept, it also discusses the comparison between HAWTs and VAWTs, future trends in design and the inherent socio-economic and environmental friendly aspects of wind energy as an alternate source of energy.
Download or read book Wind Energy Explained written by J. F. Manwell and published by Wiley-Blackwell. This book was released on 2002-06-21 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook is intended to provide an introduction to the cross-disciplinary field of wind engineering. It includes end-of-chapter tutorial sections (solutions manual available) and combines both academic and industrial experience.
Download or read book Fundamental and Advanced Topics in Wind Power written by Rupp Carriveau and published by BoD – Books on Demand. This book was released on 2011-07-05 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the fastest growing source of energy in the world, wind has a very important role to play in the global energy mix. This text covers a spectrum of leading edge topics critical to the rapidly evolving wind power industry. The reader is introduced to the fundamentals of wind energy aerodynamics; then essential structural, mechanical, and electrical subjects are discussed. The book is composed of three sections that include the Aerodynamics and Environmental Loading of Wind Turbines, Structural and Electromechanical Elements of Wind Power Conversion, and Wind Turbine Control and System Integration. In addition to the fundamental rudiments illustrated, the reader will be exposed to specialized applied and advanced topics including magnetic suspension bearing systems, structural health monitoring, and the optimized integration of wind power into micro and smart grids.
Download or read book Multiphysics of Wind Turbines in Extreme Loading Conditions written by Arash Soleiman Fallah and published by Academic Press. This book was released on 2024-01-26 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiphysics of Wind Turbines in Extreme Loading Conditions addresses the extreme transient loading of wind turbines through a multiphysics modeling approach, notably by considering the dynamic effects and the nonlinearities of the physics involved in such situations. The book forms the basis for understanding multiphysic numerical simulations conducted on onshore and offshore wind turbines and subjected to extreme loading conditions, including storms, earthquakes, blasts, impacts, and tsunamis. The multiphysics approaches used in this book are explained in each chapter, with algorithms then turned into numerical codes to attain a realistic picture of the dynamic response in each scenario. With numerical methods and loading data explained, the complexity of potential problems encountered when extreme dynamic loads are discussed, along with loading types and their effects. The book fills a specific niche in wind power, namely extreme transient loading of wind turbine, offering information and industrial practices as wind energy makes it useful to practice engineers, designers, undergraduate and graduate students. Defines best practices for unique scenarios which are not readily available in the wider literature, such as extreme load conditions, earthquake and storm scenarios Includes multi-physics methods and specific applications within the demands of extreme conditions Offers numerical simulations of both onshore and offshore wind turbines in one place
Download or read book Numerical Simulation of Wind Turbines written by Alessandro Bianchini and published by MDPI. This book was released on 2021-09-10 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book contains the research contributions belonging to the Special Issue "Numerical Simulation of Wind Turbines", published in 2020-2021. They consist of 15 original research papers and 1 editorial. Different topics are discussed, from innovative design solutions for large and small wind turbine to control, from advanced simulation techniques to noise prediction. The variety of methods used in the research contributions testifies the need for a holistic approach to the design and simulation of modern wind turbines and will be able to stimulate the interest of the wind energy community.
Download or read book Performance Numerical Simulation of a Wind Turbine with Variable Pitch Blades written by 鄭伊庭 and published by . This book was released on 2011 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:
