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Li, Jiale. "IMPROVE ENERGY PRODUCTION BY USING HIGH EFFICIENCY SMART WIND TURBINE BLADE." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1522420577009512.
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Shaheen, Mohammed Mahmoud Zaki Mohammed. "Design and Assessment of Vertical Axis Wind Turbine Farms." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439306478.
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Yilmaz, Eftun. "Benchmarking of Optimization Modules for Two Wind Farm Design Software Tools." Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1946.
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Optimization of wind farm layout is an expensive and complex task involving several engineering challenges. The layout of any wind farm directly impacts profitability and return of investment. Several software optimization modules in line with wind farm design tools in industry is currently attempting to place the turbines in locations with good wind resources while adhering to the constraints of a defined objective function. Assessment of these software tools needs to be performed clearly for assessing different tools in wind farm layout design process. However, there is still not a clear demonstration of benchmarking and comparison of these software tools even for simple test cases. This work compares two different optimization software namely openWind and WindPRO commercial software tools mutually.
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Kachhia, Bhaveshkumar Mahendrabhai. "Design and tribological issues in wind turbine bearings." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0076.
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Grandes bague de roulement utilisés dans éolienne sont l'un des éléments de transmission de charge importantes de ces machines tournantes. Ces roulements fonctionnent grâce à des cycles de charge et de la fréquence et de l'expérience des défis complexes tribologiques sévères. Le coût de remplacement de ces paliers est très élevé et conduit aussi à quantité importante de temps d'arrêt. Il est donc important de comprendre certains des principaux problèmes de conception et tribologiques de ces roulements. Quatre points type de roulement de l'anneau de contact de rotation a été considéré comme une base de référence pour cette étude pour démontrer les questions de contact de troncature et d'échec de la cage pour les roulements de hauteur. Un palier de contact à deux points de remplacement est proposé d'éliminer le contact troncature et de réduire la force de la cage accumulation. Les méthodes de conception et d'analyse démontré dans cette étude peuvent être facilement étendus à lacet paliers ainsi que d'autres grands roulements utilisés dans l'industrieLarge slewing ring bearings used in wind turbine are one of the important load transmitting elements of these rotating machines. These bearings operate through complex load and frequency cycles and experience severe tribological challenges. The cost of replacement of these bearings is very high and also leads to significant amount of down-time. It is therefore important to understand some of the major design and tribological issues in these bearings. Four-point contact slewing ring bearing type has been considered as a baseline for this study to demonstrate contact truncation and cage failure issues for pitch bearings. An alternate two-point contact bearing is proposed to eliminate contact truncation and reduce the cage force build-up. The design and analysis methods demonstrated in this study can be easily extended to yaw bearings as well as other large bearings used in the industry
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Wo, Chung. "PERFORMANCE ASSESSMENT OF THE CASE WESTERN RESERVE UNIVERSITYWIND TURBINE AND CHARACTERIZATION OF WIND AVAILABILITY." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1383338732.
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Moragues, Pons Jeremias. "Practical Experiments on the Efficiency of the Remote Presence : Remote Inspection in an Offshore Wind Turbine." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16780.
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Offshore wind power has become a growing interest in the worldwide society. New research and investigation in this kind of technology is increasing year after year. Thus, the inspection on the offshore wind turbines is expensive but necessary.The goal of this project is to demonstrate the efficiency of a Remote Inspection System inside the nacelle of an Offshore Wind Turbine. The way of carrying out inspections on real nacelles, as well as other aspects from maintenance is discussed. Three different companies have been taken into account when developing an Inspection Plan.This master thesis contains a theoretical design of the input device that would be used in the future for inspection and maintenance tasks. A gamepad has been implemented as a temporary solution for the input device.It has been demonstrated how the prototype is able to detect failures in a scenario simulating a real nacelle. Although it has not been possible to test sound, heat or vibration, this kind of things would be easily detected by adding some more additional sensors.The conclusion is that a solution for reducing maintenance tasks relies on the development of effective condition monitoring and remote control systems.
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Hamilton, Christopher. "Digital control algorithms : low power wind turbine energy maximizer for charging lead acid batteries." Honors in the Major Thesis, University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1280.
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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.Bachelors
Engineering and Computer Science
Electrical Engineering and Computer Science
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Agbali, Francis Akumabi. "DESIGN AND TESTING OF A WIND ENERGY HARNESSING SYSTEM FOR FORCED CONVECTIVE DRYING OF GRAIN IN LOW WIND SPEED, WARM AND HUMID CLIMATES." UKnowledge, 2019. https://uknowledge.uky.edu/bae_etds/66.
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Forced convective drying using a wind turbine mechanically connected to a ventilation fan was hypothesized for low cost and rapid grain drying in developing countries. The idea was tested using an expandable wind turbine blade system with variable pitch, at low wind speeds in a wind tunnel. The design was based on empirical and theoretical models embedded in a graphical user interface (GUI) created to estimate airflow-power requirements for drying ear corn. Output airflow (0.0016 - 0.0052 m3kg-1s-1) increased within the study wind speed range (2.0 - 5.5 m/s). System efficiency peak (8.6%) was observed at 3.5 m/s wind speed. Flow resistance was overcome up to 1m fill depth in 0.5 m x 0.5 m wide drying bin. Drying study at different airflow rates (no forced convection, 0.002 m3kg-1s-1 and 0.008 m3kg-1s-1) were conducted in a controlled environment at 35oC and 45% relative humidity with mean drying time; 40.3, 37.9 and 22.9 h respectively, that reduced with increasing airflow while drying the ear corn from 22% to 15% moisture content. The overall result supports the hypothesis that the wind convection system increased grain drying rates and should be further developed.
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Carneiro, Francisco Olimpio Moura. "Levantamento de Curvas de EficiÃncia de Aerogeradores de 3m de DiÃmetro Utilizando Modelos de TurbulÃncia Rans de Uma e Duas EquaÃÃes com ComparaÃÃo Experimental." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5847.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorRealizou-se o levantamento de curvas de eficiÃncia utilizando odelos numÃricos RANS de uma e duas equaÃÃes para um erogerador com 3m de diÃmetro, utilizando pÃs projetadas para operar em diferentes condiÃÃes de λ com perfis NACA 0012, 4412 e 6412. A parametrizaÃÃo da geometria da malha para a dimensÃo do rotor, juntamente com a parametrizaÃÃo do refinamento frente à capacidade dos modelos RANS obteve a independÃncia da malha à soluÃÃo. Posteriormente a anÃlise numÃrica realizou a comparaÃÃo do melhor resultado â pà projetada λ=6 com o perfil NACA 6412 â com dados experimentais. O aparato experimental foi capaz de coletar dados de rotaÃÃo e torque do rotor simultaneamente com a mediÃÃo da velocidade do vento, no qual foi obtido um valor mÃximo de eficiÃncia de aproximadamente 25% e uma faixa de operaÃÃo limitada a λ=6. Conclui-se que os modelos fornecem boa precisÃo em predizer a faixa operacional de λ, no entanto os valores de Cp foram subestimados. O modelo k-ω SST apresentou o melhor resultados dentre todos.
A survey was conducted, consisting of efficiency curves applying RANS turbulence numerical models of one and two equations for a wind turbine with a diameter of 3m, using blades designed to operate under different λ with NACA 0012, 4412 and 6412 profiles. The parameterization of the mesh geometry to the size of the rotor, together with the parameterization of the refinement level compared to the ability of RANS models reached independence from the grid to the solution. Later, a numerical analysis was performed to compare the best result â a blade designed to operate under λ = 6 with the NACA 6412 profile - against experimental data. The experimental apparatus was able to collect data rotation and torque of the rotor simultaneously with the measurement of wind velocity, which obtained a maximum efficiency of approximately 25% and an operating range limited to λ = 6. It can be concluded that the models provide good accuracy in predicting the operating range of λ, however the values of Cp were underestimated. The k-ω SST model showed the best results among all.
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Jinbo, Maro. "Contribuições ao projeto de sistemas eólicos de efeito magnus com rastreamento da máxima potência." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/12032.
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This work deals with an unconventional wind energy conversion system, in which the wind turbine has rotating cylinders rather than traditional blades. These cylinders can be driven by a brushless DC motor. The turbine operates on the physical principle called Magnus Effect. It presents the mathematical modeling of Magnus turbine and based on this modeling were carried out simulations in PSIM® software. It was implemented and was tested MPPT algorithms type HCC (Hill Climbing Control) for DC brushless motor control for operating the cylinders and hence the power generated by the Magnus turbine. Prototypes of Magnus effect wind system (turbine, generator PMSG, AC / DC converter, DC / DC converter) were built to perform wind tunnel experiments comparing the experimental results with simulated results. We sought to optimize the extraction of wind energy through concepts and innovative solutions in the construction of the turbine, brushless DC servo for rotating cylinders, implementing MPPT algorithms to control the rotation of the cylinder and the static converter. Three turbine concepts are presented and three prototypes were built. Loose cylinders were tested in the wind tunnel and it was measured the lift and drag forces. The "Prototype 3" is 3 m in diameter with two cylinders of 150 mm diameter showed the best experimental results, but still generated mechanical power did not provide an effective net power.O presente trabalho trata de um sistema eólico não convencional, cuja turbina eólica possui cilindros girantes no lugar das pás tradicionais. Estes cilindros podem ser acionados por um motor brushless CC (sem escovas). O princípio físico de funcionamento desta turbina baseia-se no que se denomina de “Efeito Magnus”. Apresenta-se a modelagem matemática da turbina Magnus e com base nesta modelagem realizam-se simulações no software PSIM®. Programa-se e testa-se algoritmos de rastreamento da máxima potência líquida MPPT (Maximum Power Point Tracking), do tipo HCC (Hill Climbing Control) no controle do motor brushless CC de acionamento dos cilindros e, consequentemente, da potência gerada pela turbina Magnus. Protótipos de sistema eólico de efeito Magnus (turbina, gerador PMSG, conversores CA/CC, CC/CC) foram construídos para realizar experimentos em túnel de vento, possibilitando comparações dos resultados experimentais com os resultados simulados. Busca-se otimizar a extração da energia dos ventos, através de concepções e soluções inovadoras na construção da turbina, servo acionamento CC brushless para os cilindros girantes, implementação de algoritmos MPPT no controle da rotação dos cilindros e do conversor estático. Três concepções da turbina Magnus são apresentadas e três protótipos construídos. Ensaios de cilindros girantes avulsos com variações nos diâmetros e nas espirais sobrepostas são realizados em túnel de vento com colméias e medem-se as forças de sustentação e de arrasto. O “Protótipo 3” de 3 m de diâmetro com dois cilindros lisos de 150 mm de diâmetro apresentou os melhores resultados experimentais, mas ainda a potência mecânica gerada não proporcionou uma potência líquida efetiva.
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Conti, Claudio. "Small-scale physical modelling of piled foundations for offshore wind turbines application." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Nowadays, finding alternative energy sources is becoming more and more important. Europe is particularly focusing on wind energy and in offshore wind energy especially. An issue concerning offshore wind energy which is gaining more and more attention is the noise emissions due to impact driven pile foundation. The noise caused by the installation process has been judged as “potentially dangerous for marine fauna” from the German Authorities.
This research thesis is part of a project which examines a viable alternative installation method for the displacement of pile foundations for offshore wind energy called pile jacking. This technology should be developed to be cost-efficient, flexibly scalable and to produce considerably reduced vibration and air pollution emissions during its placement in the sea bed. Jacked piles technology would eliminate almost any noise deriving from the hammer impact.
As most offshore piled foundations have been installed by impact driving technology, the question arises as to how piles with different the stiffness and the capacity , can otherwise be installed.
In order to delineate the significant variables affecting the load-bearing capacity and especially the ultimate uplift capacity of a pile in saturated sand, a small-scale test campaign in scale 1:30 has been performed at the Test Center for Support Structures in Hanover. The campaign was supervised by the Department for Support Structures of Fraunhofer IWES. A testing schedule comprising of 15 small-scale geotechnical physical experiments was conducted on open-ended piles to an embedded length of 75 cm using two method of pile installation: static jacking and impact driving.
The aim of this thesis is to obtain preliminary experimental data and set out the main features of this technology.
The results obtained by this study reveal that static jacking installation lead to higher resistances and is overall beneficial to the mechanical load bearing behavior of pile foundations.
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Scheubel, Christopher [Verfasser]. "The German Energy Transition and the Nuclear Phase-Out : On the Cost Efficiency of Wind Turbine Technologies, the Viability of Industrial Self-Supply, and the Effects of Decentralized Generation on the Electricity Grid / Christopher Scheubel." Baden-Baden : Nomos Verlagsgesellschaft mbH & Co. KG, 2017. http://d-nb.info/1160486689/34.
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Bekker, Johannes Cornelius. "Efficient modelling of a wind turbine system for parameter estimation applications." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20171.
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Thesis (MScEng)--Stellenbosch University, 2012ENGLISH ABSTRACT: Wind energy is a very current topic, both locally and internationally. It is one of the most rapidly growing renewable energy sources with installed capacity doubling every three years. South Africa's installed wind energy currently accounts for only 10 MW of the 197 GW worldwide installed capacity. With a 10 TWh renewable energy production target set for 2013 by the South African government, renewable energy projects have gained momentum in recent years. This target, together with data from case studies and reports on resource planning and technical requirements, shows that South Africa is well positioned for the implementation of wind energy sources. All this development in the local wind generation market creates a need for local knowledge in the field of wind energy as well as a need to efficiently model and analyse wind turbine systems and grid interactions for local operating conditions. Although the relevant model topologies are well established, obtaining or deriving appropriate parameter values from first principles remains problematic. Some parameters are also dependent on operating conditions and are best determined from site measurements using parameter estimation methodologies. One of the objectives of this project is to investigate whether the system parameter values can be obtained by performing parameter estimation on the model of a wind turbine system. The models used for parameter estimation processes require fast simulation times. Therefore, basic C-code S-function models of the wind turbine system components, i.e., the wind turbine blade, gearbox and generator, were developed and compiled as a Simulink library. These library components were then used for the parameter estimation process. The developed models, as well as the complete wind turbine system model, were validated and their performance evaluated, by comparing them to existing Simulink block models. These models all proved to be accurate and all showed reductions in simulation times. The principle of performing parameter estimation on C-code S-function models is proven by case studies performed on the individual models and the complete wind turbine system. The power coefficient matrix parameter values of the individual turbine blade model estimated with 100% accuracy for the excited elements. The individual gearbox parameter values all estimated accurately with errors below 2.5%. The parameter values of the individual generator models were estimated accurately for the ABC model, with errors below 4%, and less accurately for the DQ model with errors below 13%. The estimation results obtained for the complete wind turbine system model showed that the parameter values of the gearbox model and generator model were estimated accurately when the system model was excited through a step in angular velocity and steps in amplitude of the stator voltages respectively. A final estimation showed that a combination of gearbox and generator parameter values were accurately estimated when the model was excited through both a step in angular velocity and steps in the amplitude of the stator voltages.
AFRIKAANSE OPSOMMING: Windenergie is 'n baie aktuele onderwerp beide plaaslik en internasionaal. Windenergie is een van die vinnigste groeiende hernubare energie bronne met die geïnstalleerde kapasiteit wat driejaarliks verdubbel. Suid-Afrika se geïnstalleerde windenergie maak tans slegs 10 MW uit van die wêreldwye geïnstalleerde kapasiteit van 197 GW. Die Suid-Afrikaanse regering het ’n 10 TWh hernubare-energie produksie teiken gestel vir 2013. As gevolg hiervan het hernubare-energie projekte die laaste paar jaar momentum gekry. Hierdie teiken, tesame met die data van gevallestudies en verslae oor hulpbronbeplanning en tegniese vereistes, toon dat Suid-Afrika goed geposisioneer is vir die implementering van windenergiebronne. Hierdie ontwikkelinge in die plaaslike windenergie mark skep ’n behoefte aan plaaslike kennis op die gebied van windenergie, asook die behoefte vir ’n doeltreffende wyse vir die modellering en analisering van windturbine stelsels en netwerk integrasie vir plaaslike werkskondisies. Alhoewel die betrokke model topologieë reeds goed gevestig is, is die verkryging van toepaslike parameter waardes vanuit eerste beginsels steeds problematies. Sommige parameters is ook afhanklik van die werkskondisies en kan die beste bepaal word deur gebruik te maak van parameter estimasie metodologieë vanaf terrein metings. Een van die doelwitte van die projek is om ondersoek in te stel na die moontlikheid om die stelsel parameter waardes te verkry deur parameter estimasie toe te pas op ’n windturbine stelsel. Die modelle wat gebruik word vir die parameter estimasie prosesse benodig vinnige simulasie tye. Daarom is basiese C-kode S-funksie modelle vir die komponente van windturbine stelsels, d.w.s., die wind turbine lemme, ratkas en generator, ontwikkel en saamgestel as ’n Simulink biblioteek. Die komponente in hierdie biblioteek was toe gebruik vir die parameter estimasie proses. Die ontwikkelde modelle sowel as die hele windturbine stelsel model was gevalideer en hul werksverrigting geëvalueer, deur dit te vergelyk met bestaande Simulink blok modelle. Hierdie modelle het almal getoon dat hulle akkuraat is en het almal ’n vermindering in simulasie tyd getoon. Die beginsel van parameter estimasie wat uitgevoer word op C-kode S-funksie modelle, is bewys deur gevallestudies wat op die individuele modelle en die hele windturbine stelsel model uitgevoer was. Die geperturbeerde elemente van die kragkoëffisiënt-matriks arameter van die individuele turbine lemme model se waardes het 100% akkuraatheid geëstimeer. Die individuele ratkas model se parameter waardes was almal akkuraat geëstimeer, met foute kleiner as 2.5%. Die individuele generator modelle se parameter waardes was akkuraat geëstimeer vir die ABC model, met foute kleiner as 4%, en minder akkuraat vir die DQ model, met foute kleiner as 13%. Die resultate wat verkry is van die estimasie wat uitgevoer is op die volledige windturbine stelsel model, het getoon dat die parameter waardes van die ratkas model en die generator model akkuraat geëstimeer word, wanneer die stelsel model onderskeidelik deur ’n trap in die hoeksnelheid en trappe in die amplitude van die stator spannings geperturbeer word. ’n Finale estimasie het getoon dat ’n kombinasie van ratkas en generator parameter waardes akkuraat geëstimeer kan word as die model deur beide die trap in hoeksnelheid en die trappe in die amplitude van die stator spannings geperturbeer word.
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Ingersoll, Bryce Taylor. "Efficient Incorporation of Fatigue Damage Constraints in Wind Turbine Blade Optimization." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6985.
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Improving the wind turbine blade design has a significant effect on the efficiency of the wind turbine. This is a challenging multi-disciplinary optimization problem. During the blade design process, the aerodynamic shapes, sizing of the structural members, and material composition must all be determined and optimized. Some previous blade design methods incorporate the wind turbine's static response with an added safety factor to account for neglected dynamic effects. Others incorporate the dynamic response, but in general is limited to a few design cases. By not fully incorporating the dynamic response of the wind turbine, the final turbine blade design is either too conservative by overemphasizing the dynamic effects or infeasible by failing to adequately account for these effects. In this work, we propose two methods which efficiently incorporate the dynamic response into the optimization routine. The first method involves iteratively calculating damage equivalent fatigue that are fixed during the optimization process. We also demonstrate the training and use of a surrogate model to efficiently estimate the fatigue damage and extreme events in the design process. This surrogate model has been generalized to be used for different rated turbines, and can predict the fatigue damage of a wind turbine with less than 5% error. In general, these alternative, more efficient methods have been shown to be an adequate replacement of the more computationally expensive method of calculating the dynamic response of the turbine within the optimization routine.
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Ikonwa, Charles Amoge. "Experimental and theoretical investigations into the development of an efficient wind turbine." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/17670/.
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The small-scale wind turbine is considered as one of the most effective renewable technologies due to their potential to provide useful amount of electricity, particularly in ‘‘off-grid’’ settings as well as promising future prospects to decarbonise the power sector and ultimately stabilise energy security. Due to the huge potential of the wind resources and financial incentives, the UK is a promising region for small-scale wind energy development but there has been lack of comprehensive assessment of the wind resource for relevant locations. Thus efficient and low cost techniques are urgently needed to assess the resource potential since the long-term measurement techniques usually employed in the large-scale industry are very expensive and often not feasible for small-scale development. The research developed during this thesis focuses on cost effective techniques for predicting the wind resource using two main approaches, namely the boundary layer meteorology and measure-correlate-predict (MCP). These approaches were evaluated using a long-term dataset from the Modern Era Retrospective-Analysis and short-term onsite dataset from meteorological measurement station. To begin with, the performance of a modified methodology based on the boundary layer meteorology was evaluated at four UK sites, and the results were validated using traditional error metrics. Averaged across all sites, the percentage error in the predicted wind power density was found to be about 25% due to the uncertainties associated with the choice of the input parameters. Although the result is very encouraging, it was concluded that such a method is better applied in a ‘‘preliminary’’ analysis to identify viable sites worthy of further investigation. To reduce these uncertainties, an MCP technique was utilised along with onsite measurements over a period of 12 months at a subset of 1 of the 4 UK sites, and the results show a significant improvement on the predicted wind speed and power density. Comparison of both approaches show that the best performing MCP approaches resulted in percentage error in the predicted mean wind speed and power density of 7.2 % and 12.9 % in contrast to the 18.9 % and 17.0% obtained using the boundary layer approach. Seasonal trends, direction behaviours and frequency distribution were analysed and their characteristics reflected the general wind conditions across most UK sites. Based on the output of the wind resource assessment, the potential of a small-scale vertical axis wind turbine (VAWT) was assessed using the double multiple streamtube model. VAWTs based on the Darrieus concept are potentially more efficient and economical, but those with fixed pitch blades are inherently non self-starting and are unsuitable for decentralised application. It is shown that the self-starting problem can be alleviated by a combination of a suitable aerofoil sections, solidity and pitch angles. The thesis provides a technique for inexpensive wind resource assessment where direct long-term measurements are not feasible. In addition, it provides a suitable solution strategy to the problem of self-starting in small-scale fixed pitch wind turbines.
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Zhang, Hongkun [Verfasser]. "Torque measurement on wind turbines and its application in the determination of drivetrain efficiency / Hongkun Zhang." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2021. http://d-nb.info/1225478375/34.
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Häfele, Jan [Verfasser]. "A numerically efficient and holistic approach to design optimization of offshore wind turbine jacket substructures / Jan Häfele." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2019. http://d-nb.info/1182532586/34.
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Hübler, Clemens Janek [Verfasser], and Raimund [Akademischer Betreuer] Rolfes. "Efficient probabilistic analysis of offshore wind turbines based on time-domain simulations / Clemens Janek Hübler ; Betreuer: Raimund Rolfes." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2019. http://d-nb.info/1187440361/34.
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Norouzi, Mahdi. "An Efficient Method to Assess Reliability under Dynamic Stochastic Loads." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1349496534.
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Azevedo, Pericles Andre de Assis. "Metodologia de avaliação de rendimento de aerogeradores de pequeno porte utilizando perfis diários típicos de vento." Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7701.
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O crescimento do uso dos aerogeradores de pequeno porte em áreas
urbanas em todo o mundo aponta para um mercado em expansão e extremamente
promissor, principalmente no brasil, onde o potencial eólico é grande. tratando-se de
máquinas pequenas existe interesse dos consumidores residenciais na sua
utilização, seja para economia de energia ou por adesão às fontes alternativas.
existe uma grande quantidade de fabricantes no mundo incluindo aerogeradores de
alta, média e baixa qualidade. com isso surge a necessidade de criar métodos que
avaliem estes produtos quanto ao seu rendimento energético, como ocorrem com as
geladeiras, lâmpadas, fogões e outros, a fim de resguardar a qualidade deste
equipamento ao consumidor. a proposta é criar um ciclo de teste (ou ciclo de ventos)
baseado nos perfis de comportamentos diários de ventos urbano obtidos através de
medições reais feitos pelo projeto sonda. esse perfil será usado para testar os
aerogeradores de até 1 kw em laboratório, com auxílio de um túnel de vento a fim de
determinar o rendimento energético do conjunto gerador, servindo como método
para o aprimoramento desses aparelhos. outra possibilidade é o uso desta
metodologia no programa brasileiro de etiquetagem, que classifica os produtos em
função de sua eficiência energética. este trabalho também pode ser usado para
acreditação de laboratórios de certificação que avaliam produtos em função de sua
eficiência e/ou rendimento, visto que a acreditação é uma ferramenta estabelecida
em escala internacional para gerar confiança na atuação de organizações que
executam atividades de avaliação da conformidade.The growing use of small wind turbines in urban areas around the world points to an expanding market and extremely promising, especially in Brazil, where the wind potential is great. In the case of small machines there is consumer interest in residential use, either for energy efficiency or adherence to alternative sources. There is a lot of wind turbines manufacturers in the world including high, medium and low quality. With this comes the need to classify these products as their energy efficiency, as with refrigerators, lamps, stoves and other in order to safeguard the quality of the equipment to the customer. The proposal is to create a test cycle (or cycle of winds) based on daily behavior profiles of urban winds obtained through actual measurements made by the SONDA project. This profile will be used to test wind turbines of up to 1 kW in the laboratory, with the aid of a wind tunnel in order to determine the energy efficiency of the generator set, serving as a method for the improvement of these devices. Another possibility is the use of this methodology in the Brazilian labeling Program, which ranks the products according to their energy efficiency. This job can also be used for certification laboratory accreditation which assesses products on the basis of its efficiency and/or income, since accreditation is a tool established on an international scale to generate confidence in the activities of organizations that perform conformity assessment activities.
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Lakva, Petr. "Výroba vodíku z obnovitelného zdroje elektrické energie." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230583.
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Hydrogen, as a form of storage for the excess energy from renewable sources, is a technically and economically viable option. However, the technology is not mature enough to compete with the other renewable energy possibilities. In this thesis, a study based on coupling two 330 kW wind-turbines with an NELP. 40 electrolyzer this connection should improve the utilization of wind power. In this thesis are two options of energy utilization. The energy produced by the wind-turbine is stored in the form, of hydrogen and is then delivered for consumption at variable power through a fuel cell, second option is use of produced hydrogen as alternative fuel for cars. This study is a general introduction for the wind energy system with hydrogen storage. Future studies should be more complex and detailed in order to understand and model the system with greater accuracy and to increase the possibility for the utilization of wind energy to generate hydrogen. This would enhance wind power competitiveness and sustain the continuously changing world energy demands.
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Chlebný, Radek. "Autonomní dům aneb život grid-off." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220159.
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This thesis deals with energy self-sufficiency focusing on the independence of the electric grid. Basic line emanating project form a concrete proposal for autonomous energy supply system. Emphasis is placed primarily on photovoltaic systems, electric energy accumulation and selection of individual components of such a system. Another important part of the thesis is also an economic evaluation of design variations. The thesis also deals with a market research, and thereof derived benefit assessment of each technology. The accompanying chapters are then devoted to the history of autonomous life style or classification of buildings according to their energy performance.
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Tsai, Chih-Wei, and 蔡志威. "Investigation on Evaluation Factors of Wind Turbine Efficiency." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/23142345303855575853.
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碩士國立臺灣大學
生物環境系統工程學研究所
94
The efficiency of thermal, hydraulic, and nuclear power plants can be evaluated by using capacity factor, due to the fact that fuels are continually supplied and properly managed. On the other hand, wind velocity is the fuel of wind turbine. It is never steady and has the cubic relationship with wind energy. Small perturbation in wind speed can result in substantial difference in wind energy. It is thus not adequate to only use capacity factor in the evaluation of wind power plants. Chang et al. (2003) suggests that three wind turbine parameters (capacity factor, wind turbine efficiency and availability factor) have to be considered in analyzing wind energy production. Based on the result of Chang et al. (2003), the main objective of this study is to further investigate the above three wind turbine parameters and their relationship with wind turbine characteristics (such as cut-in velocity, rated velocity, and wind characteristics). Eight different wind turbines at four strong-wind meteorological stations (Wuchi, Tungchitao, Lanyu and Hengchun) in Taiwan are tested. The simulated results show that the slope of the power curve (from cut-in to rated velocity) greatly affects capacity factor of wind turbine. It is concluded that capacity factor can distinguish wind energy production in strong and weak wind periods. However, it cannot be used to determine the suitability of wind turbine installation due to its low recognition of wind turbine characteristics. In contrast, wind turbine efficiency can be applied to demonstrate the optimal wind turbine under different turbine characteristics. Finally, availability factor is classified into un-rated availability factor and rated availability factor, which can clearly express the detailed information of wind turbine operation.
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Huang, Chen Wei, and 黃振瑋. "Match Design and Efficiency Improvement of Vertical Axis Wind Turbine." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/02783043612921521940.
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碩士國立交通大學
機械工程學系
101
The purpose of this thesis is to develop a device for adjusting the pitch angles of the wind blades and reduce cogging torque of a permanent magnet generator so that the efficiency of the vertical-axis wind turbine (VAWT) can be increased. We calculate the efficiencies of the VAWT for different pitch angles. The pitch angle that can produce the best efficiency of the VAWT is then used to design the pitch angle adjusting device which is a cam type mechanism. To start rotation at a lower wind speed, we utilize the advantages of resisting type wind blades for the wind turbine. At the central part of the VAWT, two C-shape resisting blades are used to generate torque at low wind speed while at the outer part, two vertical wind blades of airfoil shape are used to produce torque at mid-to-high wind speed. A wind direction tracking mechanism is developed to adjust the pitch angles of the wind blades according to wind direction. In reducing the cogging torque of a permanent magnet generator, the slot/pole ratio and magnet spread angle are calculate to choose the proper values for the design of the generator. The maximum power point tracking curve is also determined for the future design of the control module.
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Marques, Pedro Miguel Teixeira. "Efficiency of a gearbox lubricated with wind turbine gear oils." Dissertação, 2012. http://hdl.handle.net/10216/68298.
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Pusha, Ayana T. "Multiple turbine wind power transfer system loss and efficiency analysis." 2013. http://hdl.handle.net/1805/3800.
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Indiana University-Purdue University Indianapolis (IUPUI)A gearless hydraulic wind energy transfer system utilizes the hydraulic power transmission principles to integrate the energy of multiple wind turbines in a central power generation location. The gearless wind power transfer technology may replace the current energy harvesting system to reduce the cost of operation and increase the reliability of wind power generation. It also allows for the integration of multiple wind turbines to one central generation unit, unlike the traditional wind power generation with dedicated generator and gearbox. A Hydraulic Transmission (HT) can transmit high power and can operate over a wide range of torque-to-speed ratios, allowing efficient transmission of intermittent wind power. The torque to speed ratios illustrates the relationship between the torque and speed of a motor (or pump) from the moment of start to when full-load torque is reached at the manufacturer recommended rated speed. In this thesis, a gearless hydraulic wind energy harvesting and transfer system is mathematically modeled and verified by experimental results. The mathematical model is therefore required to consider the system dynamics and be used in control system development. Mathematical modeling also provided a method to determine the losses of the system as well as overall efficiency. The energy is harvested by a low speed-high torque wind turbine connected to a high fixed-displacement hydraulic pump, which is connected to hydraulic motors. Through mathematical modeling of the system, an enhanced understanding of the HTS through analysis was gained that lead to a highly efficient hydraulic energy transmission system. It was determined which factors significantly influenced the system operation and its efficiency more. It was also established how the overall system operated in a multiple wind turbine configuration. The quality of transferred power from the wind turbine to the generator is important to maintaining the systems power balance, frequency droop control in grid-connected applications, and to ensure that the maximum output power is obtained. A hydraulic transmission system can transfer large amounts of power and has more flexibility than a mechanical and electrical system. However high-pressure hydraulic systems have shown low efficiency in wind power transfer when interfaced with a single turbine to a ground-level generator. HT’s generally have acceptable efficiency at full load and drop efficiency as the loading changes, typically having a peak around 60%. The efficiency of a HT is dependent on several parameters including volumetric flow rate, rotational speed and torque at the pump shaft, and the pressure difference across the inlet and outlet of the hydraulic pump and motor. It has been demonstrated that using a central generation unit for a group of wind turbines and transferring the power of each turbine through hydraulic system increases the efficiency of the overall system versus one turbine to one central generation unit. The efficiency enhancement depends on the rotational speed of the hydraulic pumps. Therefore, it is proven that the multiple-turbine hydraulic power transfer system reaches higher efficiencies at lower rotational speeds. This suggests that the gearbox can be eliminated from the wind powertrains if multiple turbines are connected to the central generation unit. Computer simulations and experimental results are provided to quantify the efficiency enhancements obtained by adding the second wind turbine hydraulic pump to the system.
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Marques, Pedro Miguel Teixeira. "Efficiency of a gearbox lubricated with wind turbine gear oils." Master's thesis, 2012. http://hdl.handle.net/10216/68298.
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Huang, Po-Wen, and 黃柏聞. "Structural Failure Analysis and Efficiency Improvement of Composite Wind Turbine Blade." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/43203988515300611526.
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碩士國立交通大學
機械工程學系
100
In this thesis, the failure and efficiency enhancement of composite wind blades are investigated. The basic aerodynamic principles are used to modify the twisting angle of a wind blade with airfoil shape NACA4418. The efficiency of the wind blade has been increased approximately 15%. A finite element model is established to study the deformation and failure strength of the wind blade. The suitability of the finite element model in predicting the deformation of the wind blade has been validated by experimental results. The first-ply failure load as well as the buckling load of the wind blade has been determined using the finite element mode. The layups of the composite blade skin have been designed for the wind blade to sustain the wind speed of 60m/s.
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Ortega, Mirna Monserrat Machado, and 瑪安妮. "Research and Development of Low Start Wind Speed and High Efficiency Vertical Axis Wind Turbine." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/98602295187338224371.
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碩士崑山科技大學
機械工程研究所
98
There are many types of Vertical Axis Wind Turbines (VAWT), the Wollongong design, originally conceived in Australia is a very interesting type, because it presents a gear mechanism with a high potential for commercial application. Theoretically there are many options of gear configurations, and the relationship between the number of teeth of each gear (Gear Ratio = G) has an essential impact on the function of the Wollongong turbine. In order to establish the most suitable G for the construction of the turbine, a Numerical Analysis was carried out. Through this analysis it could be concluded that a G= -1/2 would be the best option to obtain an acceptable performance, which means a larger amount of positive work. Once the best Gear Ratio was defined and could be substantiated by a Numerical Analysis, the Experimental Tests were the next step. First, a Savonius turbine was acquired which included a device to measure the voltage; this equipment was used for both turbines, in order to compare them under similar conditions. Some improvements were done to the Savonius VAWT; this consisted in the adaptation of pair of bearings to reduce the oscillatory movement, hence the efficiency would be higher. When the Savonius VAWT was in optimal conditions, the construction of the Wollongong VAWT was done through CAD and Rapid Prototyping (3D Printing) technology. The most important consideration regarding to the Wollongong turbine, beside the gear configuration, was that the measure equipment of the Savonius turbine will have to be adapted into this one. Finally both turbines were compared, and the results revealed that the Wollongong VAWT was much more efficient than the Savonius VAWT, which indicates high potential for commercial application.
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Yu-HsiangTsao and 曹淯翔. "Power output efficiency in large wind farms with different streamwise turbine spacing." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/z9rzf7.
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Bader, Shujaut. "Improving the Efficiency of Wind Farm Turbines using External Airfoils." 2017. https://scholarworks.umass.edu/masters_theses_2/549.
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Wind turbine efficiency typically focuses on the shape, orientation, or stiffness of the turbine blades. In this thesis, the focus is instead on using static fixed airfoils in proximity to the wind turbine to control the airflow coming out of the turbine. These control devices have three beneficial effects. (1) They gather air from “higher up” where the air is moving faster on average (and therefore has more kinetic energy in it). (2) They throw the used (and slowed down air) downwards. This means that any turbines in the wind farm behind the lead turbines do not get “stale” air. (3) These control devices provide a large stabilizing lifting force for floating off-shore turbines. In this study, Reynolds-Averaged Navier-Stokes (RANS) simulations of an aligned array of two wind turbines along with various designs of these control devices is studied. The recovery in the velocity at the inlet plane of downstream turbine due to the controlled flow facilitated by these devices is measured with respect to the average streamwise wind velocity at the inlet plane of upstream turbine. A customized numerical solver was written in C++ using Opensource Field Operation And Manipulation (OpenFOAM) to model the turbines as actuator discs with axial induction and to generate an inlet velocity field similar to a turbulent atmospheric boundary layer (ABL). All the design configurations use a streamlined (airfoil shaped) structure, at an angle of attack carefully selected to prevent flow separation depending upon its location around the turbine. For strong wake displacement, the devices are placed in proximity to the upstream wind turbine so as to facilitate a substantial downwash of the faster wind from upper layers of the ABL and at the same time deflect the wake out of the way of the downstream turbine. Also, the pressure coefficient across the upstream turbine augmented with these devices can sometimes become more negative than a bare turbine, which in turn increases the mass flow rate of air passing through it, thereby also increasing the leading turbine’s efficiency slightly.
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CHEN, JHIH-MING, and 陳志明. "Power Efficiency Analysis of a Vertical Axial Wind Turbine with Different Chord Length." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/znt2w9.
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碩士逢甲大學
智能製造與工程管理碩士在職學位學程
107
In recent years, the global warming and the warnings of climate change drive governments to save energy and reduce carbon emmision, and find alternative energy resources to reduce dependence on fossil oil energy. In order to achieve carbon reduction and low cost, some countries tend to use nuclear power. But since the 2011 Fukushima 311 nuclear disaster in Japan, many countries "abandon nuclear and adopt renewable", therefore renewable energy development has more room. In this thesis, the main objective is to design an 1kW vertical axis wind turbine (VAWT). First of all, the Geometry and CFX modules of commercial software ANSYS are used to construct the blades and simulate the power generated by the wind turbine. Then, diffenent wind speeds and blade chord lengths are applied to understand their affections to wind turbine’s efficiency. After several improved designs, the power of wind turbine has been increase 30% at operation point: 12m/s wind speed and 2000RPM turbine angular velocity.
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Shang-YuHan and 韓尚育. "Numerical Study of Aerodynamic Efficiency and Noise for Small Vertical Axis Wind Turbine." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/68343802138273612678.
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Chang, Yao-Kang, and 張剛耀. "The Numerical Analysis of Power Efficiency and Aerodynamic Loading in Small Wind Turbine Rotors." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/33141255540183052445.
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碩士大葉大學
機械工程研究所碩士班
94
The purpose of this project is to analyze aerodynamic loading and power efficiency of small wind turbine rotors using numerical method. The mathematic model of aerodynamics of wind turbine rotor in quasi-state is developed based on disk theory, the momentum theory, angular momentum theory and blade element momentum theory. The strip theory is utilized to perform the numerical analysis of mathematic rotor model. The numerical prediction of axial forces, hub moments, torques and pitching moments related to blade positions are reported in this study. The influence of wind velocity and rotational frequency on aerodynamic loadings and power efficiency of rotor is investigated and reported in this research. The conclusions and suggestions are addressed in the end of this report.
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Boa-WeiChen and 陳柏維. "Power output efficiency in large wind farms with different turbine-array configurations and different incoming flow conditions." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4nkeju.
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Sousa, João Pedro Barbosa de. "Design and dimensioning of a test rig for efficiency measurements of wind turbine gearboxes up to 2.5 MW." Dissertação, 2016. https://repositorio-aberto.up.pt/handle/10216/86169.
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Sousa, João Pedro Barbosa de. "Design and dimensioning of a test rig for efficiency measurements of wind turbine gearboxes up to 2.5 MW." Master's thesis, 2016. https://repositorio-aberto.up.pt/handle/10216/86169.
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Kopřiva, Tomáš. "Obnovitelné zdroje energie jako námět pro fyzikální experimenty." Master's thesis, 2018. http://www.nusl.cz/ntk/nusl-387288.
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Title: Renewable Energy Sources as Inspiration for Physics Experiments Author: Bc. Tomáš Kopřiva Department: Department of Physics Education Supervisor: RNDr. Petr Kácovský, Ph.D. Abstrakt: This thesis deals with a current issue of renewable resources of energy. It focuses on the Sun, wind and hydrogen as energy resources.The first part of the thesis provides a theoretical explanation to these resources and is followed by a practical part with the aim to explain this issue to students by using experiments included in worksheets. The theoretical part is focused on the minimal knowledge that is needed for completing the worksheets. This part also describes suitability of these resources in the context of the Czech Republic. The second part of the thesis is exclusively experimental. It describes educational kits that can be used to demonstrate renewable resources of energy. It also includes instructions to create worksheets. The attachment, which is part of the thesis, contains a set of worksheets and a CD which, among others, contains other worksheets filled in by students. Key words: renewable resources, worksheet, experiment, solar cell, fuel cell, wind turbine, efficiency
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Gamas, Eduardo Lourenço. "Modelação de Sistemas de Energia Renovável em Edifícios." Master's thesis, 2017. http://hdl.handle.net/10316/83193.
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Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e TecnologiaNuma altura em que a introdução de energia renovável em edifícios se torna cada vez mais importante devido às metas Europeias, no âmbito do programa Europa 2020, é necessário conseguir selecionar os equipamentos de produção de energia que consigam fazer o melhor aproveitamento dos recursos naturais com a maior eficiência possível.Neste contexto, foram implementados sistemas de produção de energia através de painéis fotovoltaicos e turbinas eólicas, no algoritmo de uma ferramenta computacional, que permite avaliar, simular e optimizar o desempenho térmico e energético de edifícios gerados por essa ferramenta.Esta implementação conteve as fases de modelação dos sistemas no software EnergyPlus, seguida da criação dos objetos do sistema numa base de dados e a implementação dos sistemas no algoritmo. Por fim, foram realizados casos de estudo que permitiram chegar à conclusão sobre quais os melhores sistemas a implementar para cada uma das cinco localizações estudadas.O objetivo principal deste desenvolvimento será conseguir prever os consumos energéticos de cada edifício e modelar soluções de microgeração de energia que evitem o sobre-dimensionamento e consequente desperdício de energia.Foi possível perceber que, com os preços praticados atualmente, um sistema de produção deste tipo não tem o benefício expectável comparando com o elevado investimento no sistema mas, prevendo uma diminuição dos preços dos equipamentos ao longo dos anos, o investimento num sistema deste tipo tornar-se-á mais vantajoso.
As renewable energy in buildings is gaining more importance nowadays due to European targets under Europe 2020 program, it is necessary to be capable of selecting energy production equipments that can make a better use of natural resources, highly available in Portugal, with the best efficiency possible.In this context, photovoltaic and wind turbine energy production systems were implemented in an algorithm of a computational tool that access, evaluate and optimize thermal and energetic performance and also visual comfort of the buildings generated by that tool.This implementation contained the stages of system modeling in EnergyPlus software followed by the creation of a database with the objects needed in the system and the implement of the systems in the algorithm. Finally, case studies were conducted in order to conclude which are the ideal systems to select in each of the five studied locations in Portugal.The main objective of this development will be the ability to predict energetic consumptions of each building and model microgeneration energy solutions that will avoid over-dimensioning and consequent energy waste.It was possible to realize that energy production systems equal to the ones tested don't have the expected revenue when comparing with the high investment, considering todays' prices but, predicting a decrease in the cost of equipments during the years and an increase in the price of energy sold, an investment in these types of systems will become more profitable.
Outro - Este trabalho tem o apoio da Fundação para a Ciência e Tecnologia (FCT) e do Fundo Europeu de Desenvolvimento Regional (FEDER) via COMPETE - Programa Operacional Competitividade e Internacionalização (POCI), no âmbito do projeto Ren4EEnIEQ (PTDC/EMS-ENE/3238/2014 e POCI-01-0145-FEDER-016760, respetivamente)
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Lee, Meng-Chieh, and 李孟杰. "Numerical Simulation Methods to Explore Efficient H-type Vertical Axis Wind Turbine." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/41913603405542370143.
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碩士健行科技大學
電機工程系碩士班
102
Small vertical axis wind turbines have the benefits of simple structure and noiseless. It is suitable to be applied for living houses. In this paper a CFD software is adopted to simulate H-type rotors with the same cross section area under three different configuration ratios and to investigate which configuration has maximum energy output. Simulation models are built up using two most popular software (SolidWorks and ZWcad) and compared their simulation outputs. The average torque of rotor model from SolidWorks is about 18% of that from ZWcad. It indicates the modeling software ZWcad is more suitable for our CFD simulation software. Three different blades with pitch angle of -5°, 0° and 5° are simulated and analyzed. The results demonstrate the average torque for the blade with 5° is the largest as the angular speed is less than 700RPM and has the best performance over all. This result can be a reference for high efficiency vertical axis wind turbines design. The tall and thin H-type rotor is found to have the maximum output power based on the CFD simulation results for the rotors with different configuration ratios.
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Gully, Benjamin Houston. "Hybrid powertrain performance analysis for naval and commercial ocean-going vessels." Thesis, 2012. http://hdl.handle.net/2152/ETD-UT-2012-08-6270.
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The need for a reduced dependence on fossil fuels is motivated by a wide range of factors: from increasing fuel costs, to national security implications of supply, to rising concern for environmental impact. Although much focus is given to terrestrial systems, over 90% of the world's freight is transported by ship. Likewise, naval warfighting systems are critical in supporting U.S. national interests abroad. Yet the vast majority of these vessels rely on fossil fuels for operation. The results of this thesis illustrate a common theme that hybrid mechanical-electrical marine propulsion systems produce substantially better fuel efficiency than other technologies that are typically emphasized to reduce fuel consumption. Naval and commercial powertrains in the 60-70 MW range are shown to benefit substantially from the utilization of mechanical drive for high speed propulsion; complemented by an efficient electric drive system for low speed operations. This hybrid architecture proves to be able to best meet the wide range of performance requirements for each of these systems, while also being the most easily integrated technology option. Naval analyses evaluate powertrain options for the DDG-51 Flight III. Simulation results using actual operational profile data show a CODLAG system produces a net fuel savings of up to 12% more than a comparable all-electric system, corresponding to a savings of 37% relative the existing DDG-51 powertrain. These results prove that a mechanical linkage for the main propulsion engine greatly reduces fuel consumption and that for power generation systems requiring redundancy, diesel generators represent a vastly superior option to gas turbines. For the commercial application it is shown that an augmented PTO/PTI hybrid system can better reduce cruise fuel consumption than modern sail systems, while also producing significant benefit with regard to CO2 emissions. In addition, using such a shaft mounted hybrid system for low speed electric drive in ports reduces NOx emissions by 29-43%, while CO is reduced 57-66% and PM may be reduced up to 25%, depending on the specific operating mode. As an added benefit, fuel consumption rates under these conditions are reduced 20-29%.text