CFD Based Design and Analysis of Building Mounted Wind Turbine with Diffuser Shaped Shroud

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ISBN 13 :
Total Pages : 96 pages
Book Rating : 4.:/5 (111 download)

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Book Synopsis CFD Based Design and Analysis of Building Mounted Wind Turbine with Diffuser Shaped Shroud by : Abilash Krishnan

Download or read book CFD Based Design and Analysis of Building Mounted Wind Turbine with Diffuser Shaped Shroud written by Abilash Krishnan and published by . This book was released on 2015 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: The production of sustainable energy is one of the biggest challenges facing us today. Wind and solar technologies are the leaders for clean energies. Wind energy is in relatively plentiful supply, can be used efficiently and is a nonpolluting power production method. Within this paradigm, building-integrated micro wind turbines are promising low cost renewable energy devices, but are fraught with challenges like low wind speeds and high turbulence intensity. In this thesis, a comprehensive study of increased performance of a wind turbine design inside a diffuser shaped shroud on building roofs is conducted. A commercial Computational Fluid Dynamics (CFD) model is used to simulate unsteady 3D flows inside the diffuser and around the turbine. The meshing strategy and model used is verified using a grid refinement study. The geometric modifications and various non-dimensional parametric studies conducted are also described in detail, along with the relevant discussion of results obtained. Furthermore, the coefficient of power of the turbine is improved from 0.135 to 0.394, representing an improvement of almost 300%. This improvement can largely be attributed to the flanged diffuser shroud design, as well as the modifications made to the blades of the turbine.

CFD Analysis of the Influence of Guide Vanes on a Roof Mounted VAWT with a Diffuser-Shaped Shroud and Flange

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ISBN 13 :
Total Pages : 67 pages
Book Rating : 4.:/5 (113 download)

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Book Synopsis CFD Analysis of the Influence of Guide Vanes on a Roof Mounted VAWT with a Diffuser-Shaped Shroud and Flange by : Hamza Abu-Thuraia

Download or read book CFD Analysis of the Influence of Guide Vanes on a Roof Mounted VAWT with a Diffuser-Shaped Shroud and Flange written by Hamza Abu-Thuraia and published by . This book was released on 2018 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in wind power and tidal power have grown considerably to offer a clean and sustainable energy alternative. Nevertheless, distributed small-scale energy production from wind in urban areas has been disappointing due to very low turbine efficiencies. Hence, it is the objective of this thesis to study and analyze the performance of a novel wind turbine design, a seven bladed Savonius vertical axis wind turbine (VAWT), which is horizontally oriented inside a diffuser-shaped shroud with a flange and attached with four deflectable guide vanes, mounted on the top of a building, which is shown to have the potential to achieve higher efficiencies. The flow field over the turbine is analyzed by using Computational Fluid Dynamics (CFD) Software Package of Star CCM+, on a three-dimensional (3D) grid for multiple tip speed ratio (TSR) at four different guide vane angles of 35°, 45°, 55° and 65°, while keeping all vanes open. Another case was analyzed where selected vanes would be open while closing others. In this work, the wind flow directly facing the turbine is studied to compute the coefficient of power Cp. The coefficient of power with detachable guide vane attached was found to be 0.333 at vane angle of 55°. Finally, the most effective case is when the bottom vane is closed compared to the bottom two vanes closed. This case with only one closed vane achieves a maximum Cp value of 0.398.

CFD Analysis of the Characteristics of a Shrouded Turbine

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Publisher : diplom.de
ISBN 13 : 3832470441
Total Pages : 86 pages
Book Rating : 4.8/5 (324 download)

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Book Synopsis CFD Analysis of the Characteristics of a Shrouded Turbine by : Maximilian Ludwig Ganis

Download or read book CFD Analysis of the Characteristics of a Shrouded Turbine written by Maximilian Ludwig Ganis and published by diplom.de. This book was released on 2003-07-25 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inhaltsangabe:Abstract: Wind energy is an increasingly import source of renewable, clean energy. In spite of this, only the methods and the materials of construction have improved over time, while the basic working principle of the wind turbine is still the same as it was centuries ago. In this thesis we have increased the power of a wind turbine by a factor of 4 in a fluid dynamic simulation, using a very simple external shroud system. We have also extended the theory of wind turbines (limit of Betz), to include this new kind of device and show why past attempts to augment the power of a wind turbine by means of shroud systems have failed. A detailed analysis of the device and its functioning principle is presented in this thesis - optimization studies need to be done in the future. Inhaltsverzeichnis:Table of Contents: AbstractI IndexII List of FiguresIV List of SymbolsVI Introduction1 1.Theory of Wind Turbines5 1.1Introduction5 1.2The Betz Law6 1.3Aerodynamics of the rotor13 1.4Rotor Power Characteristics18 1.5Number of Rotor Blades20 1.6Horizontal Axis Wind Turbines (HAWT)22 1.7Shrouded / Ducted Wind Turbines28 1.7.1Ducted Rotor29 1.7.2Turbine with a Diffuser Duct29 2.Methodology33 2.1Introduction33 2.2Computational Domain34 2.3Computational Code41 2.3.1Conservation Equations42 2.3.2K-Epsilon Turbulence Model43 2.3.3Discretization of the Conservation Equations45 2.4MFR - Multiple Frame of Reference45 2.5Parallel Processing46 2.6Simulations47 3.Results48 3.1Introduction48 3.2Conventional Turbine49 3.2.1Velocity Field49 3.2.2Static Pressure Field52 3.2.3Total Pressure Field53 3.2.4Power of the Conventional Turbine55 3.2.5Energy and Momentum Transfer57 3.3Shrouded Turbine59 3.3.1Velocity Field59 3.3.2Static Pressure Field62 3.3.3Total Pressure Field63 3.3.4Power of the Shrouded Turbine65 3.3.5Energy and Momentum Transfer66 3.3.6The Betz Limit68 3.3.7Cross Check Analysis with Traditional Shrouded Turbines69 Conclusions72 Bibliography73 Acknowledgments

Augmenting Urban Wind Energy

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ISBN 13 :
Total Pages : 100 pages
Book Rating : 4.:/5 (113 download)

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Book Synopsis Augmenting Urban Wind Energy by : Aierken Dilimulati

Download or read book Augmenting Urban Wind Energy written by Aierken Dilimulati and published by . This book was released on 2018 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increased demand for renewable energy and the development of energy independent building designs have motivated significant research into the improvement of wind power technologies that target urban environments. However, the implementation of wind turbines in urban environments still faces many challenges. The complexity of wind profile and high turbulence due to the topographical characteristics of urban environments severely limit the performance of urban wind turbines. To explore possible solutions to such challenges and better understand them, the current state of urban wind energy is thoroughly reviewed and the urban flow characteristics are investigated using computational fluid dynamics (CFD). Promising directions that can improve urban wind turbine performance are identified. A flanged shrouded diffuser mechanism - a fluid machine, mounted on rooftop of buildings used as a casing for small wind turbines can significantly improve turbine performance. The fluid machine can increase the wind energy potential by up to a factor of four, by guiding and accelerating the airflow over the building roofs utilizing its geometric features such as, cycloidal curve surface at the inlet and a vortex generating flange at the outlet. The performance of the fluid machine is tested using CFD and wind tunnel tests are also performed. To provide further evidence for its performance, the diffuser mechanism is modeled on the rooftop of an existing building in a test site in Montreal, Canada using CFD and the topographical map including the geometrical data of the buildings in the test site. The CFD analysis performed on the diffuser mechanism in the test site used real statistical wind data of the city of Montreal. CFD investigation of the test site found close agreement with the initially predicted performance of the mechanism. As a power-augmenting device, the fluid machine can mitigate the challenges faced by the urban wind energy systems and it opens new ways to improving energy efficiency of urban wind turbines.

Advances in Sustainable Energy

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Publisher : Springer
ISBN 13 : 3030056368
Total Pages : 213 pages
Book Rating : 4.0/5 (3 download)

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Book Synopsis Advances in Sustainable Energy by : Ahmad Vasel

Download or read book Advances in Sustainable Energy written by Ahmad Vasel and published by Springer. This book was released on 2019-03-29 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reveals key challenges to ensuring the secure and sustainable production and use of energy resources, and provides corresponding solutions. It discusses the latest advances in renewable energy generation, and includes studies on climate change and social sustainability. In turn, the book goes beyond theory and describes practical challenges and solutions associated with energy and sustainability. In particular, it addresses: · renewable energy conversion technologies; · transmission, storage and consumption; · green buildings and the green economy; and · waste and recycling. The book presents the current state of knowledge on renewable energy and sustainability, supported by detailed examples and case studies, making it not only a cutting-edge source of information for experts and researchers in the field, but also an educational tool for related undergraduate and graduate courses.

Analysis and Optimization of Shrouded Horizontal Axis Wind Turbines

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ISBN 13 :
Total Pages : 174 pages
Book Rating : 4.:/5 (18 download)

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Book Synopsis Analysis and Optimization of Shrouded Horizontal Axis Wind Turbines by : Tariq Abdulsalam Khamlaj

Download or read book Analysis and Optimization of Shrouded Horizontal Axis Wind Turbines written by Tariq Abdulsalam Khamlaj and published by . This book was released on 2018 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: So-called wind-lens turbines offer the potential for improved energy efficiency and better suitability for urban and suburban environments compared to unshrouded or bare wind turbines. Wind-lenses, which are typically comprised of a diffuser shroud equipped with a flange, can enhance the wind velocity at the rotor plane due to the generation of a lower back pressure. This work comprises of two main studies which aim to develop fast and accurate simulation tools for the performance prediction and design of shrouded horizontal axis wind turbines. In the first study, a low-order theoretical model of ducted turbines is developed to establish a better understanding of the basic aerodynamics of shrouded wind turbines. Then a cost-effective CFD tool coupled with a multi-objective genetic algorithm is developed and employed to improve the performance of shrouded wind turbines. A low-order semi empirical model, which offers performance prediction for the power and thrust coefficients, is developed and applied to shrouded turbines. This 1D model is based on assumptions and approximations to calculate optimal power coefficients and power extraction, as well as augmentation ratios. It is revealed that the power enhancement is proportional to the mass stream rise produced by the nozzle diffuser-augmented wind turbine (NDAWT). Such mass flow rise can only be accomplished through two essential principles: an increase in the area ratios and/or by reducing the negative back pressure at the exit. The thrust coefficient for optimal power production of a conventional bare wind turbine is known to be 8/9, whereas the theoretical analysis of the NDAWT predicts an ideal thrust coefficient either lower or higher than 8/9 depending on the back-pressure coefficient at which the shrouded turbine operates. Computed performance expectations demonstrate a good agreement with numerical and experimental results, and it is demonstrated that much larger power coefficients than for traditional wind turbines are achievable. Lastly, the developed model is found to be very well suited for the preliminary design of shrouded wind turbines where typically many trade-off studies need to be conducted inexpensively. Then a higher fidelity model is developed and implemented to calculate the power, thrust, and drag coefficients by solving the Reynolds-averaged Navier-Stokes (RANS) equations with the k-epsilon turbulence model for the flow within and around diffuser augmented wind turbines using the open source software OpenFOAM. To reduce the computational cost, the turbine rotor itself is modeled by incorporating blade element momentum body forces into the RANS equations. Realistic rotor data for the sectional lift and drag coefficients for all angles of attacks are utilized via look-up tables. Grid convergence studies for verification and comparisons with experiments for validation are carried out to demonstrate that the adopted methodology is able to accurately predict the performance of a wind-lens prior to performing shape optimizations. Finally, the wind-lens performance is increased by designing the shroud and wind turbine shapes as well as flange height through an optimization process that seeks to maximize the power while minimizing drag and thrust forces. The employed optimizer is a multi-objective genetic algorithm (MOGA). Bezier curves are used to define the chord and twist distribution of the turbine blades and a piece-wise quadratic polynomial is utilized to define the shroud shape. It is demonstrated that the resulting optimal designs yield significant improvements in the output power.

CFD Based Analysis and Parametric Study of a Novel Wind Turbine Design

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ISBN 13 :
Total Pages : 116 pages
Book Rating : 4.:/5 (111 download)

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Book Synopsis CFD Based Analysis and Parametric Study of a Novel Wind Turbine Design by : Gabriel Naccache

Download or read book CFD Based Analysis and Parametric Study of a Novel Wind Turbine Design written by Gabriel Naccache and published by . This book was released on 2016 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small Vertical Axis Wind Turbines (VAWTs) are good candidates to extract energy from wind in urban areas because they are easy to install, service and do not generate much noise; however, the aerodynamic efficiency of small turbines is low. Here-in a new turbine, with high aerodynamic efficiency, is proposed. The novel design is based on the classical H-Darrieus VAWT. VAWTs produce the highest power when the blade chord is perpendicular to the incoming wind direction. The basic idea behind the proposed turbine is to extend that said region of maximum power by having the blades continue straight instead of following a circular path. This motion can be performed if the blades turn along two axes; hence it was named Dual Vertical Axis Wind Turbine (D-VAWT). The analysis of this new turbine is done through the use of Computational Fluid Dynamics (CFD) with 2D and 3D simulations. While 2D is used to validate the methodology, 3D is used to get an accurate estimate of the turbine performance. The analysis of a single blade is performed and the turbine shows that a power coefficient of 0.4 can be achieved. So far, reaching performance levels high enough to compete with the most efficient VAWTs. The D-VAWT is still far from full optimization, but the analysis presented here shows the hidden potential and serves as proof of concept. The study of the D-VAWT is concluded with a preliminary parametric study of the turbine sensitivity to different incoming wind angles, turbine axes spacing, number of blades, airfoil profile and blade mounting point.

CFD Based Synergistic Analysis of Wind Turbine for Roof Mounted Integration

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Publisher :
ISBN 13 :
Total Pages : 85 pages
Book Rating : 4.:/5 (111 download)

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Book Synopsis CFD Based Synergistic Analysis of Wind Turbine for Roof Mounted Integration by : Patrick André Larin

Download or read book CFD Based Synergistic Analysis of Wind Turbine for Roof Mounted Integration written by Patrick André Larin and published by . This book was released on 2016 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increasing global demand for energy and environmental concerns have provoked a shift from exhaustible, fossil fuel based energy to renewable energy sources. It is clear that wind energy will play an important role in satisfying our current and future energy demands. In this paper, a horizontal configuration of a Savonius and cup type wind turbines are proposed to be mounted on the upstream edge of a building, in such a way that its low performance is improved by taking advantage of the flow acceleration generated by the edge of the building. The importance of integrated simulations which include both the building and the turbine is shown and it is also demonstrated that the individual calculations of the flow around the building and the turbine individually cannot be superposed. Following the validation of the methodology with experimental data, the performance of the Savonius wind turbines placed in the vicinity of the edge of the building top was calculated. The position, blade number, and circumferential length were then investigated when the turbine is mounted on a building. The objective is to better understand wind turbine behavior for low speed urban environments. The flow fields of conventional Savonius and cup type turbines were solved using Computational Fluid Dynamics (CFD) in 3D domains. The optimal configuration shows an improvement in the power coefficient from 0.043 to 0.24, representing an improvement of 450%. The improvement also demonstrates that although cup type blades show very poor performance in free stream flow, they perform well in the right environment.

Towards Sustainable Cities in Asia and the Middle East

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Publisher : Springer
ISBN 13 : 3319616455
Total Pages : 240 pages
Book Rating : 4.3/5 (196 download)

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Book Synopsis Towards Sustainable Cities in Asia and the Middle East by : John Calautit

Download or read book Towards Sustainable Cities in Asia and the Middle East written by John Calautit and published by Springer. This book was released on 2017-07-11 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents innovative work on innovative methods, tools and practices aimed at supporting the transition of Asian and Middle Eastern cities and regions towards a more smart and sustainable dimension. The role of the built and urban environment are becoming more pronounced in Asia and Middle East as the regions continues to experience rapid increase in population and urbanisation, which have only led to an increase in environmental degradation but also rise in energy consumption and emissions. Individual chapters covers timely topics such as sustainable infrastructure, transportation, renewable energy, water and methods supporting an innovative and sustainable development of urban areas. Real-world examples are presented to highlight recent developments and advancements in design, construction and transportation infrastructures. This volume is part of the proceedings of the 1st GeoMEast International Congress and Exhibition on Sustainable Civil Infrastructures, Egypt 2017.

CFD Analysis of a Shrouded Wind Turbine from High Efficiency and Output Power

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Publisher :
ISBN 13 :
Total Pages : 126 pages
Book Rating : 4.:/5 (1 download)

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Book Synopsis CFD Analysis of a Shrouded Wind Turbine from High Efficiency and Output Power by : David P. Ferguson

Download or read book CFD Analysis of a Shrouded Wind Turbine from High Efficiency and Output Power written by David P. Ferguson and published by . This book was released on 2017 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the shrouded wind turbine has been proven superior to a conventional bare wind turbine, the main objective of this research was to analyze thin-walled diffuser designs and determine their effect on the surrounding airflow in order to yield the highest wind speed through the turbine blades and thus the highest output of power.

Environmental Wind Engineering and Design of Wind Energy Structures

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Publisher : Springer Science & Business Media
ISBN 13 : 3709109531
Total Pages : 353 pages
Book Rating : 4.7/5 (91 download)

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Book Synopsis Environmental Wind Engineering and Design of Wind Energy Structures by : Charalambos Baniotopoulos

Download or read book Environmental Wind Engineering and Design of Wind Energy Structures written by Charalambos Baniotopoulos and published by Springer Science & Business Media. This book was released on 2011-12-01 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents a state-of-the-art in environmental aerodynamics and the structural design of wind energy support structures, particularly from a modern computational perspective. Examples include real-life applications dealing with pollutant dispersion in the building environment, pedestrian-level winds, comfort levels, relevant legislation and remedial measures. Design methodologies for wind energy structures include reliability assessment and code frameworks.

Recent Advances in CFD for Wind and Tidal Offshore Turbines

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Publisher : Springer
ISBN 13 : 3030118878
Total Pages : 148 pages
Book Rating : 4.0/5 (31 download)

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Book Synopsis Recent Advances in CFD for Wind and Tidal Offshore Turbines by : Esteban Ferrer

Download or read book Recent Advances in CFD for Wind and Tidal Offshore Turbines written by Esteban Ferrer and published by Springer. This book was released on 2019-02-06 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents novel Computational Fluid Dynamics (CFD) techniques to compute offshore wind and tidal applications. The papers in this volume are based on a mini-symposium held at ECCOMAS 2018. Computational fluid dynamics (CFD) techniques are regarded as the main design tool to explore the new engineering challenges presented by offshore wind and tidal turbines for energy generation. The difficulty and costs of undertaking experimental tests in offshore environments have increased the interest in CFD which is used to design appropriate turbines and blades, understand fluid flow physical phenomena associated with offshore environments, predict power production or characterise offshore environments amongst other topics.

CFD for Wind and Tidal Offshore Turbines

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Publisher : Springer
ISBN 13 : 3319162020
Total Pages : 134 pages
Book Rating : 4.3/5 (191 download)

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Book Synopsis CFD for Wind and Tidal Offshore Turbines by : Esteban Ferrer

Download or read book CFD for Wind and Tidal Offshore Turbines written by Esteban Ferrer and published by Springer. This book was released on 2015-06-09 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book encompasses novel CFD techniques to compute offshore wind and tidal applications. Computational fluid dynamics (CFD) techniques are regarded as the main design tool to explore the new engineering challenges presented by offshore wind and tidal turbines for energy generation. The difficulty and costs of undertaking experimental tests in offshore environments have increased the interest in the field of CFD which is used to design appropriate turbines and blades, understand fluid flow physical phenomena associated with offshore environments, predict power production or characterise offshore environments, amongst other topics.

CFD Analysis of Wind Power Potential Across Rooftop Gaps of Tall Buildings

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ISBN 13 :
Total Pages : 71 pages
Book Rating : 4.:/5 (123 download)

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Book Synopsis CFD Analysis of Wind Power Potential Across Rooftop Gaps of Tall Buildings by : Gargi Kailkhura

Download or read book CFD Analysis of Wind Power Potential Across Rooftop Gaps of Tall Buildings written by Gargi Kailkhura and published by . This book was released on 2017 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study uses Computational Fluid Dynamics (CFD) modeling to analyze the dependence of wind power potential and turbulence intensity on aerodynamic design of a special type of building with a nuzzle-like gap at its rooftop. Numerical simulations using ANSYS Fluent are carried out to quantify the above-mentioned dependency due to three major geometric parameters of the building: (i) the height of the building, (ii) the depth of the roof-top gap, and (iii) the width of the roof-top gap. The height of the building is varied from 8 m to 24 m. Likewise, the gap depth is varied from 3 m to 5 m and the gap width from 2 m to 4 m. The aim of this entire research is to relate these geometric parameters of the building to the maximum value and the spatial pattern of wind power potential across the roof-top gap. These outcomes help guide the design of the roof-top geometry for wind power applications and determine the ideal position for mounting a micro wind turbine. From these outcomes, it is suggested that the wind power potential is greatly affected by the increasing gap width or gap depth. It, however, remains insensitive to the increasing building height, unlike turbulence intensity which increases with increasing building height. After performing a set of simulations with varying building geometry to quantify the wind power potential before the installation of a turbine, another set of simulations is conducted by installing a static turbine within the roof-top gap. The results from the latter are used to further adjust the estimate of wind power potential. Recommendations are made for future applications based on the findings from the numerical simulations.

CFD-based Methodology for Wind Farm Layout Optimization

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (133 download)

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Book Synopsis CFD-based Methodology for Wind Farm Layout Optimization by : Enrico Antonini

Download or read book CFD-based Methodology for Wind Farm Layout Optimization written by Enrico Antonini and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Driven by concerns on climate change and global warming, increasing oil prices, government support and public receptiveness, wind energy harvesting is emerging as one of the fastest growing renewable energy technologies. Most wind energy is nowadays produced by wind farms, which consist of hundreds of turbines to take advantage of economies of scale. Wind farm performance is however affected by the wakes generated by the turbines which can significantly diminish their annual energy production. Accurate wake effect predictions and reliable wind farm layout design become therefore critical aspects to the economic success of a wind farm project. The present research project aims therefore to define an innovative design framework that integrates accurate wake effect predictions for the development of the next generation wind farms as part of the strategy for promoting the transition to a renewable energy generation. Computational fluid dynamics (CFD) provides a unique tool to simulate wind turbine wakes because of its capability to provide a complete solution for the flow field in complex configurations. Nevertheless, CFD simulations are strongly influenced by the choice of the turbulence model used to close the Reynolds-averaged Navier-Stokes (RANS) equations. We therefore conducted an analysis of different turbulence models and their influence on the results of CFD wind turbine simulations to suggest the most suitable for such applications. Even though proper turbulence modeling is adopted, several studies showed however that the effectiveness of RANS models in wind farm simulations has not always been consistent. We therefore hypothesized this limitation to arise from uncertainties generated by the wind direction variability and proposed a modeling framework that, by accounting for such uncertainties, consistently improved the agreement of the CFD predictions with the experimental observations. To integrate the CFD models in a design methodology, we developed an innovative continuous adjoint formulation for gradient calculations within the framework of a gradient-based wind farm layout optimization. By testing this optimization methodology under different wind farm configurations, wind resource distributions and terrain topography, we showed that this unique CFD-based design framework effectively improved the annual energy production of a proposed wind farm by optimally siting its turbines.

Unsteady and Three-dimensional CFD Simulation of a Darrieus Turbine on the Roof of a Building

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Publisher :
ISBN 13 :
Total Pages : 76 pages
Book Rating : 4.:/5 (113 download)

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Book Synopsis Unsteady and Three-dimensional CFD Simulation of a Darrieus Turbine on the Roof of a Building by : Samson Victor

Download or read book Unsteady and Three-dimensional CFD Simulation of a Darrieus Turbine on the Roof of a Building written by Samson Victor and published by . This book was released on 2017 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: The disastrous effect of climate change has motivated scientists and engineers around the world to reduce dependency on fossil fuels. Among many alternative sources of energy, power production by wind energy has increased exponentially for last few years. Along this spectrum, efforts are made to investigate the possibility to install wind turbine on high roof tops. The onsite generation will also help to integrate micro wind turbines with urban areas. The proposed research work focuses on the CFD study of a Vertical Axis Wind Turbine (Troposkien-shaped) mounted on the upstream edge of a building, so that flow acceleration generated by the edge of the building contributes to enhance performance of the turbine. The CFD methodology validation is done by comparison of performance with experimental data. Geometric configuration of Sheldahl’s models is used for unsteady 3D flow of roof mounted Troposkien wind turbine. Three different turbine placement positions at different heights are investigated to observe Cp - n curve sensitivity at various tip speed ratios. Position 1 and Position 2 are at the edge of the building, whereas position 3 is a few meters away from the edge, directed towards the geometric center of a building. To simulate realistic atmospheric wind conditions, wind gradient is imposed at the inlet, with fixed desired velocity pointing to the middle of the wind turbine. Geometry and numerical setup is described in details, along with the obtained results. The optimal placement position of the turbine shows improvement in the power coefficient from 0.33 to 0.4 at low wind speeds.

CFD Based Estimation of Wind Energy Potential in Urban Locations

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Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (139 download)

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Book Synopsis CFD Based Estimation of Wind Energy Potential in Urban Locations by : Anahita Ghassemi Panah

Download or read book CFD Based Estimation of Wind Energy Potential in Urban Locations written by Anahita Ghassemi Panah and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wind energy plays a critical role as a safe and clean source of energy. However, the complexity of wind patterns produced by the topographical characteristics of urban environments considerably affect the performance of urban wind turbines. In order to address these effects, this study utilizes both Computational Fluid Dynamics (CFD) and meteorological data in order to simulate the wind flow in an urban area and to predict the performance of a wind turbine at specific locations on top of buildings. This thesis presents a review of vertical axis wind turbines and the desirable locations of these types of wind turbines above a building in an urban area. Numerical simulations offer a cost-effective method with an acceptable accuracy to evaluate wind turbine locations. Two test cases have been studied to illustrate the behavior of wind turbines located on the roofs of buildings. The full scale of the urban area and the computational domain are constructed, and the flow is simulated based on the STAR CCM+ ® software. The three-dimensional, steady Reynolds-Averaged Navier-Stokes equations are solved to obtain the velocity of the wind in urban areas. Meteorological data is then used to estimate the potential energy production at specific locations on the top of a building. Multiple locations are studied in terms of annual total Energy output to find out the best potential position for turbine installation. Results demonstrate a significant difference of energy output for different locations of the wind turbines on the same building. This study introduces an effective tool to study the annual total energy output potential at multiple locations above the building in much shorter time span (within a month) rather than the existing experimental or field methods.