Dissertations / Theses on the topic '3D finite element'
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KATRAGADDA, SRIRAMAPRASAD. "FINITE ELEMENT ANALYSIS OF 3D CONTACT PROBLEMS." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1123812018.
Full textXuefang, Zhao. "3D Finite Element Modeling of the Lower Limb." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Produktutveckling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-31013.
Full textLjungberg, Björn. "3D Finite Element Modelling of ICRH in JET." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-253263.
Full textDenna masteruppsats utvärderar möjligheten att använda finita elementmetoden till att lösa den elektro-magnetiska vågekvationen i ett fusionsplasma i 3D. Speciellt väljs frekvensen för att matcha frekvensen för uppvärmning genom joncyklotronresonans i fusionsexperimentet JET. I detta arbete ges en översiktlig introduktion till fusion, åtföljd av en förklaring av dämpningsprocessen i ett plasma. En projektion av 3D-vågfältet på ett poloidalt plan jämförs med 2D-vågfältet producerat av 2D-koden FEMIC för att validera den utvecklade 3D-koden. Jämförelsen gjordes med gott resultat.| |Effektspektrumet och kopplingsresistansen per toroidal mod från 3D-modellen jämförs också med motsvarande storheter från en analytisk 1D-modell. Trots att vissa skillnader kan ses nära det toroidala modtalet n = 0 och för högre modtal ( n > 70), är utseendet på effektspektrumen lika. Skillnaden nära n = 0 tillskrivs de inducerade strömmarna i reaktorväggen, medan för högre modtal beror skillnaden troligen på dålig upplösning. De inducerade strömmarna i väggen ger upphov till singulariteter i den valda modellen för kopplingsresistansen. Det resulterar i otillförlitliga värden tansen.
Hart, Andrew. "3D finite element computer modelling of the human patella." Thesis, Teesside University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410836.
Full textFan, Yuanji. "3D Finite Element Analysis of a Hybrid Stepper Motor." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-278496.
Full textHybridstegsmotorer appliceras i fler ochfler industriapplikationer tack vare deras låga kostnad och förbättrad prestanda jämfört med servomotorer. Många branschapplikationer kräver exakta och effektiva metoder för att förutsäga motorns prestanda redan i konstruktionsstadiet. Motorns geometri är komplicerad och den magnetiska mättnadseffekten är också betydande, vilket försvårar modelleringen. Dessutom är drivkretsen och styralgoritmen mer sofistikerad än den för traditionella växeleller likströmsmotorer. Vidare så resulterar motorns förluster i temperaturökningar vilka påverkar dynamiska.Alla dessa faktorer kan studeras genom att simulera hybrida stegmotorer med en modell som kombinerar effekten av elektromagnetiskt fält, kontrollalgoritm och motorförluster tillsammans. I detta examensarbete utvecklas en tredimensionell finit elementmodell i programvaran Maxwell för att studera motorns elektromagnetiska egenskaper. Det elektromagnetiska fältet analyseras i ett statiskt tillstånd. Den beräknade mot-EMK:n har verifieras genom experiment. Vektorkontrollalgoritmen tillämpas på modellen genom samsimulering i Simulink och Maxwell i Simplorer. Den tredimensionella modellen visade sig vara orealistisk för samsimulering. Till sist summeras uppnådaerfarenheter och rekommendationer för fortsatt arbete ges.
Ahsan, Nabeel. "OCTG Premium Threaded Connection 3D Parametric Finite Element Model." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/71791.
Full textMaster of Science
Palani, Vijayakumar Bahr Behnam. "Finite element simulation of 3D drilling in unidirectional CFRP composite." Diss., Click here for available full-text of this thesis, 2006. http://library.wichita.edu/digitallibrary/etd/2006/t079.pdf.
Full text"May 2006." Title from PDF title page (viewed on October 29, 2006). Thesis adviser: Behnam Bahr. Includes bibliographic references (leaves 85-89).
Pester, Matthias. "Visualization Tools for 2D and 3D Finite Element Programs - User's Manual." Universitätsbibliothek Chemnitz, 2006. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200600436.
Full textSOUSA, RAFAEL ARAUJO DE. "GEOMETRIC AND NUMERICAL ADAPTATIVITY OF 2D AND 3D FINITE ELEMENT MESHES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10376@1.
Full textTECNOLOGIA EM COMPUTAÇÃO GRÁFICA
Este trabalho apresenta uma metodologia para geração de malhas adaptativas de elementos finitos 2D e 3D usando modeladores geométricos com multi-regiões e superfícies paramétricas. A estratégia adaptativa adotada é fundamentada no refinamento independente das curvas, superfícies e sólidos. Inicialmente as curvas são refinadas, no seu espaço paramétrico, usando uma técnica de partição binária da curva (binary-tree). A discretização das curvas é usada como dado de entrada para o refinamento das superfícies. A discretização destas é realizada no seu espaço paramétrico e utiliza uma técnica de avanço de fronteira combinada com uma estrutura de dados do tipo quadtree para gerar uma malha não estruturada de superfície. Essas malhas de superfícies são usadas como dado de entrada para o refinamento dos domínios volumétricos. A discretização volumétrica combina uma estrutura de dados do tipo octree juntamente com a técnica de avanço de fronteira para gerar uma malha sólida não estruturada de elementos tetraédricos. As estruturas de dados auxiliares dos tipos binary-tree, quadtree e octree são utilizadas para armazenar os tamanhos característicos dos elementos gerados no refinamento das curvas, superfícies e regiões volumétricas. Estes tamanhos característicos são definidos pela estimativa de erro numérico associado à malha global do passo anterior do processo adaptativo. A estratégia adaptativa é implementada em dois modeladores: o MTOOL (2D) e o MG (3D), que são responsáveis pela criação de um modelo geométrico, podendo ter, multi-regiões, onde no caso 3D as curvas e superfícies são representadas por NURBS.
This work presents a methodology for adaptive generation of 2D and 3D finite-element meshes using geometric modeling with multi- regions and parametric surfaces. The adaptive strategy adopted in this methodology is based on independent refinements of curves, surfaces and solids. Initially, the model´s curves are refined using a binary-partition algorithm in parametric space. The discratizetion of these curves is used as input for the refinement of adjacent surfaces. Surface discretization is also performed in parametric space and employs a quadtree-based refinement coupled to an advancing-front technique for the generation of an unstructured triangulation. These surface meshes are used as input for the refinement adjacent volumetric domains. Volume discretization combines an octree refinement with an advancing-front technique to generate an unstructural mesh of tetrahedral elements. In all stages of the adaptive strategy, the refinement of curves, surface meshes and solid meshes is based on estimated numerical errors associated to the mesh of the previous step in the adaptive process. In addition, curve and surface refinement takes into account metric distortions between parametric and Cartesian spaces and high curvatures of the model´s geometric entities. The adaptive strategies are implemented in two different modelers: MTOOL (2D) and MG (3D), which are responsible for the creation of a geometric model with multi-regions, where for case 3D the curves and surfaces are represented by NURBS, and for the interactive and automatic finite-element mesh generation associated to surfaces and solid regions. Numerical examples of the simulation of engineering problems are presented in order to validate the methodology proposed in this work.
Gao, Sasa. "Development of a new 3D beam finite element with deformable section." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI026/document.
Full textThe new beam element is an evolution of a two nodes Timoshenko beam element with an extra node located at mid-length. That extra node allows the introduction of three extra strain components so that full 3D stress/strain constitutive relations can be used directly. The second step is to introduce the orthotropic behavior and carry out validation for large displacements/small strains based on Updated Lagrangian Formulation. A series of numerical analyses are carried out which shows that the enhanced 3D element provides an excellent numerical performance. Indeed, the final goal is to use the new 3D beam elements to model yarns in a textile composite preform. For this purpose, the third step is introducing contact behavior and carrying out validation for new 3D beam to beam contact with rectangular cross section. The contact formulation is derived on the basis of Penalty Formulation and Updated Lagrangian formulation using physical shape functions with shear effect included. An effective contact search algorithm is elaborated. And a consistent linearization of contact contribution is derived and expressed in suitable matrix form, which is easy to use in FEM approximation. Finally, some numerical examples are presented which are only qualitative analysis of contact and checking the correctness and the effectiveness of the proposed 3D beam element
Cuamatzi, Meléndez Rubén. "3D cellular automata finite element modelling of cleavage and ductile fracture." Thesis, University of Sheffield, 2009. http://etheses.whiterose.ac.uk/10332/.
Full textSmethurst, Christopher. "A Finite Element Solution of the Natural Convection Problem in 3D." Thesis, University of Manchester, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517825.
Full textDu, Huifeng. "Finite element analysis of adhesive contact interface in continuous 3D printing." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127164.
Full textCataloged from the official PDF of thesis.
Includes bibliographical references (pages 65-68).
Projection Micro-Stereolithography (P[mu]SLA) is one of the most high-throughput additive manufacturing methods, yet preserving the high-resolution characteristic of light-based polymerization techniques. However, further improvement of fabrication speed and precision is usually hindered by the undesired adhesive forces at the curing interface, which is an inevitable consequence of in situ liquid-to-solid phase transition. To overcome this limitation, a bio-inspired super low adhesive interface has been proposed based on the observation of a slippery water layer on the peristome surface of pitcher plant. This hydrophobic layer provides an effective shield to solid adhesion due to its low adhesive energy, and attracting force between fabricated part and UV curing interface is significantly reduced. The introduction of this new lubrication layer not only remarkably improves the fabrication speed, but also increases the refilling rate of liquid pre-polymer resin.
This ultra-low adhesive interface shows promises for pushing the boundaries of continuous 3D printing into a realm of high-throughput additive manufacturing methods ready for industrial applications. In this thesis, I sought to provide a more comprehensive understanding of the solid-solid interaction at the curing interface of 3D photo-polymerizing systems. The state-of- the-art review of current literature suggested that a surface-based cohesive contact theory from a continuum mechanics perspective was the most appropriate model to establish a connection between interfacial material properties and macroscopic measurement results from experiment. Based on that I analyzed the entire mechanical separation process using finite-element method, and provided a semi-quantitative explanation of the stability of such lubricant-infused nano-cavities against peeling forces.
This research lays the ground for elucidating the physical mechanism behind the general adhesion-separation problem, and framework has been constructed in a more general form to allow for analyzing a wide range of interdisciplinary problems involving the dynamics of anisotropic moving contact lines and the propagation of surface instabilities induced by adhesive contact.
by Huifeng Du.
S.M.
S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering
Alankar, Alankar. "Development of a 3D microstructure sensitive crystal plasticity model for aluminum." Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Dissertations/Spring2010/A_Alankar_020910.pdf.
Full textGolshayan, Maryam. "A study of internal defibrillation efficacy using finite element analysis: a 3D isotropic finite element model of the myocardium electric fields." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18790.
Full textLa fibrillation ventriculaire (FV) est un état dans lequel la cavité inférieure du coeur montre une motion asynchrone et chaotique, empêchant le coeur de pomper le sang et l'oxygène au corps. La FV est considérée comme un arrêt cardiaque soudain, responsable de la mort subite de 300,000 personnes chaque année aux Etats-Unis. Afin d'inverser cette condition mortelle, le recours le plus efficace est la délivrance d'un choc électrique directement au niveau du coeur à l'aide d'un Défibrillateur Cardioverteur Implantable (DCI). Le principal problème de l'utilisation des DCIs est le placement des électrodes défibrillateurs pour permettre au courant d'être conduit optimalment à travers du muscle cardiaque, en particulier, le myocarde ventriculaire gauche. Selon l'hypothèse de la masse critique, la défibrillation sera réussi quand 75% du tissu de myocarde est inactivé par le choc de défibrillation. Le seuil de défibrillation ou la tension efficace minimale exigée pour donner des résultats réussis est suggéré d'être liés à la distribution du gradient de la tension myocardique, toutefois, il n'a pas été mesurée. En outre, le but est de maintenir le seuil de défibrillation aussi bas que possible pour essayer de maximiser le succès de la défibrillation, réduire au minimum le risque des dommages de myocarde et des arythmies cardiaques provoqués par des chocs à haute intensité, et aussi permettre de réduire la taille de la batterie ainsi que prolonger la durée de la vie utile du dispositif. De diverses techniques numériques ont été utilisées pour modeler le coeur afin de résoudre les équations régissant requises pour obtenir la distribution de gradient de la tension myocardique pendant la défibrillation. La méthode des éléments finis (FEM) a été d'intérêt particulier car elle peut gérer les domaines irréguliers, les hétérogénéité de matériel, et les conditions aux limites complexe de problèmes dans la bioélec
Hedenstierna, Sofia. "3D Finite Element Modeling of Cervical Musculature and its Effect on Neck Injury Prevention." Doctoral thesis, Stockholm : Teknik och hälsa, Kungliga Tekniska högskoaln, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9503.
Full textNewman, Kyle D. "3D Modeling and Finite Element Analysis of Femur After Removing Surgical Screws." OpenSIUC, 2016. https://opensiuc.lib.siu.edu/theses/2025.
Full textKacar, Onur. "3d Finite Element Modelling Of Surface Excavation And Loading Over Existing Tunnels." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608538/index.pdf.
Full textShah, Bhavik Rameshchandra. "3D finite element analysis of integral abutment bridges subjected to thermal loading." Thesis, Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/388.
Full textNicholas, P. J. "3D finite element investigation of crack growth in compact tension fracture specimens." Thesis, Swansea University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638329.
Full textAhmed, Naseer. "3D finite element modelling of ultrasonically assisted turning of high strength alloy." Thesis, Loughborough University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445374.
Full textWilliam, Gergis W. "Backcalculation of pavement layers moduli using 3D nonlinear explicit finite element analysis." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=530.
Full textTitle from document title page. Document formatted into pages; contains ix, 166 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 149-158).
Almeida, Erika Oliveira de [UNESP]. "Prótese protocolo com barra pré-fabricada: comportamento ósseo variando o tipo de osso e a configuração horizontal do arco mandibular no MEF-3D." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/97387.
Full textA barra pré-fabricada é uma opção de tratamento vantajosa por minimizar o tempo de confecção da prótese implantossuportada do tipo protocolo de carga imediata com níveis de adaptação e passividade previsíveis. No entanto, para a sua aplicação, o arco do paciente deve adaptar-se anatomicamente ao formato da barra pré-fabricada, e a qualidade óssea deve ser compatível com a indicação da carga imediata. Além disso, a literatura não apresenta dados numéricos sobre a influência de diferentes formatos horizontais do arco mandibular na distribuição das tensões no osso, assim como não é homogênea a definição do critério de análise a ser utilizado quando materiais frágeis, como o osso, são estudados utilizando o método dos elementos finitos. Devido a isso, foi realizada uma revisão da literatura com o objetivo de relacionar as propriedades dos materiais estudados com o critério de análise adotado. Para isto, foram levantados 2061 artigos através do indexador Medline database, durante os anos de 2004 a 2008. Observou-se que tanto o critério das tensões de von Mises como a máxima tensão principal foram utilizados para o estudo dos materiais considerados frágeis ou não. Para o estudo da influência de diferentes formatos horizontais do arco mandibular e diferentes tipos de osso na distribuição das tensões no osso cortical e medular na simulação de uma prótese fixa implantossuportada do tipo protocolo mandibular confeccionada através do sistema pré-fabricado Neopronto (Neodent, Implante Osseointegrável), quatro modelos (M) representativos...
Prefabricated bar is a profitable treatment option for minimizing the preparation time of fixed protocol-type prosthesis in immediate load with adaptation levels and predictable passivity. Nevertheless, in order to be applied, the patient's arch must be anatomically adapted to the format of the prefabricated bar, and bone quality must be compatible to immediate load indication. However, literature does not show any numerical data about the influence of different horizontal formats of the mandibular arch on bone stress distribution, as well as it is not homogeneous which analysis criterion is to be used when friable materials, such as the bone, are studied by making use of the finite element method. Due to this, a literature review was elaborated with the purpose to relate the materials' properties through the adopted analysis criterion. Therefore, 2061 articles were raised through the Medline Database Indexer from 2004 to 2008. It was noticed that not only Von Mises's equivalent stress criterion but also maximum principal stress were used for the study of materials considered as friable or not. For the study of the influence of different horizontal formats of mandibular archs and different types of bone in stress distribution on the cortical and medular bone in simulating a fixed implant-supported protocol-type mandibular prosthesis prepared through the Neopronto prefabricated system (Neodent, Osseointegratable Implant), four representative models (M) of a totally endentulate mandibular arch restored by the Neopronto prefabricated system (Neodent, Osseointegratable Implant) over four interforaminal implants were prepared through the SolidWorks 2007 program with a bone range (I to IV) (M.I - M.II - M.III - M.IV), considering the horizontal dimension as of regular size... (Complete abstract click electronic access below)
Song, Huimin. "Rigorous joining of advanced reduced-dimensional beam models to 3D finite element models." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33901.
Full textRinaldi, Elisa. "3D Finite Element Analysis of Wheel/Rail normal contact problem using ANSYS software." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Find full textUnlu, Mehmet Zubeyir. "Iterative deformable finite element model for nonrigid 3D PET/MRI breast image registration." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2006. http://proquest.umi.com/login?COPT=REJTPTU0NWQmSU5UPTAmVkVSPTI=&clientId=3739.
Full textDe, Frias Lopez Ricardo. "A 3D finite beam element for the modelling of composite wind turbine wings." Thesis, KTH, Bro- och stålbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119079.
Full textButz, Alexander [Verfasser]. "Nichtlineare Formulierung piezoelektrischer 3D-Stabstrukturen : Theorie und Finite-Element-Modellierung / von Alexander Butz." Karlsruhe : Inst. für Baustatik, 2006. http://d-nb.info/1003446272/34.
Full textVALVERDE, NILTHSON NORENA. "3D ELASTOPLASTIC ANALYSIS FOR SHALLOW FOUNDATIONS AND EMBANKMENTS BY THE FINITE ELEMENT METHOD." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33096@1.
Full textCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
PROGRAMA DE EXCELENCIA ACADEMICA
BOLSA NOTA 10
A grande maioria das obras geotécnicas, tais como algumas fundações, aterros e escavações, apresentam uma configuração geométrica tipicamente tridimensional. No entanto, em função da complexidade da obtenção de soluções considerando os aspectos inerentes à condição de deformação e tensão tridimensionais, as análises destas obras têm sido comumente realizadas adotando-se as aproximações de deformação plana e/ou axissimétrica. Esta dissertação apresenta um modelo computacional baseado na formulação em deslocamento do método dos elementos finitos para a simulação de problemas mecânicos de equilíbrio estático de obras geotécnicas em condição tridimensional. São ressaltados os problemas de capacidade de carga de fundações superficiais e a simulação da construção de aterros. O solo é considerado como um material não linear elasto-plástico e os modelos não associados Mohr-Coulomb modificado e Lade-Kim são adotados para representar sua relação tensão-deformação resistência. As estratégias de solução não linear, tanto a nível global quanto em nível de ponto de Gauss, são apresentadas e discutidas. Os exemplos de capacidade de carga das fundações superficiais são comparados com os resultados da teoria do equilíbrio limite e da análise limite indicando bons resultados. O efeito da tensão intermediária na trajetória de tensão é apresentado e discutido nos exemplos de simulação da construção de aterros.
The vast majority of geotechnical works, such as some foundations, embankments and excavations, show a typical three-dimensional geometric configuration. However, depending on the complexity of obtaining solutions considering the aspects inherent to the three-dimensional deformation and stress, the analysis of these works have been performed by adopting common approaches and plane strain or axisymmetric. This dissertation presents a computational model based on displacement formulation of finite element method for simulation of mechanical problems of static equilibrium condition of geotechnical works in three dimensions. It highlights the problems of load capacity of shallow foundations and the simulation of embankment construction. The soil is considered as material non-linear elastic-plastic models and non-associated Mohr- Coulomb and modified Lade-Kim are adopted to represent their relationship stress-strain-resistance. The nonlinear solution strategies, both overall and in the Gauss point level, are presented and discussed. Examples of load capacity of shallow foundations are compared with the results of the theory of limit equilibrium and limit analysis showing good results. The effect of tension in the intermediate stress path is presented and discussed in the simulation examples of the construction of embankments.
Schutte, Jacques. "Optimisation of a transverse flux linear PM generator using 3D Finite Element Analysis." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17930.
Full textENGLISH ABSTRACT: Several transverse flux and longitudinal flux linear generator topologies exist for freepiston Stirling engine applications. In this thesis the transverse flux permanent magnet linear generators are investigated together with a back-to-back converter which can deliver the electrical energy from the linear generator to the electrical network. The transverse flux permanent magnet linear generator is geometrically optimised with the aim to maximise the power-to-weight ratio while maintaining preset power and efficiency levels. An optimised 3 kW linear generator is built and the measured results correlate to the simulation results. A close-loop current control scheme is introduced to control the current of the rectifier, which is part of the back to back converter. The transverse flux permanent magnet linear generator is connected to the input of the rectifier which has the ability to force a specific current from the generator. The measured results of the rectifier correlate to the results of the simulations that were done. The current control present some complications and it is suggested that another control scheme is used. A close-loop voltage control scheme is introduced for the control of the DC bus voltage. The DC bus is connected between the rectifier and the inverter, which is the other part of the back-to-back converter. A close-loop current control scheme is introduced to control the inverter current that flows from the inverter to the electrical network. The measured results of the inverter and the DC bus correlate to the results of the simulations that were done. The results of the system, including the generator, rectifier and inverter, tested as a unit is presented and discussed.
AFRIKAANSE OPSOMMING: Verskeie tranverse vloed en longitudinale vloed lineˆere generator topologie¨e bestaan vir vrysuier Stirling enjin toepassings. In hierdie tesis word ’n transverse vloed permanente magneet lineˆere generator ondersoek saam met ’n omsetter. Die omsetter dra die elektriese energie van die generator oor aan die elektriese netwerk. Die transverse vloed permanente magneet lineˆere generator word geometries geoptimeer met die doel om die drywing-tot-gewig verhouding te maksimiseer terwyl vasgestelde drywing en effektiwiteit vlakke behou word. ’n Geoptimeerde 3kW lineˆere generator prototipe is vervaardig en die gemete resultate is geverifieer met die simulasie resultate. ’n Geslote lus stroombeheer strategie word voorgestel om die stroom te beheer van die gelykrigter, wat deel is van die omsetter. Die transverse vloed permanente magneet lineˆere generator word aan die gelykrigter, wat die vermo¨e het om ’n spesifieke stroom uit die generator te forseer, se intree verbind. Die gemete resultate van die gelykrigter wat gebou is stem goed ooreen met die van die simulasies wat gedoen is. Die stroombeheer hou komplikasies in wat bespreek word. Dus word die gebruik van ’n alternatiewe stroombeheer voorgestel. ’n Geslote lus spannings beheer strategie¨e word voorgestel om die gs. busspanning te beheer. Die gs. bus is gekonnekteer tussen die gelykrigter en die wisselrigter, wat ook deel uitmaak van die omsetter. ’n Geslote lus stroom beheer word voorgestel om die stroom te beheer wat vanaf die wisselrigter na die elektriese netwerk toe vloei. Die gemete resultate van die wisselrigter en die gs. bus stem goed ooreen met die van die simulasies wat gedoen is. Die resultate van die hele stelsel, wat die generator, gelykrigter en die wisselrigter insluit, wat as ’n eenheid getoets is word weergegee en bespreek.
Yang, Xiaoyan. "Dynamic simulation of 3D weaving process." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/18970.
Full textDepartment of Mechanical and Nuclear Engineering
Youqi Wang
Textile fabrics and textile composite materials demonstrate exceptional mechanical properties, including high stiffness, high strength to weight ratio, damage tolerance, chemical resistance, high temperature tolerance and low thermal expansion. Recent advances in weaving techniques have caused various textile fabrics to gain applications in high performance products, such as aircrafts frames, aircrafts engine blades, ballistic panels, helmets, aerospace components, racing car bodies, net-shape joints and blood vessels. Fabric mechanical properties are determined by fabric internal architectures and fabric micro-geometries are determined by the textile manufacturing process. As the need for high performance textile materials increases, textile preforms with improved thickness and more complex structures are designed and manufactured. Therefore, the study of textile fabrics requires a reliable and efficient CAD/CAM tool that models fabric micro-geometry through computer simulation and links the manufacturing process with fabric micro-geometry, mechanical properties and weavability. Dynamic Weaving Process Simulation is developed to simulate the entire textile process. It employs the digital element approach to simulate weaving actions, reed motion, boundary tension and fiber-to-fiber contact and friction. Dynamic Weaving Process Simulation models a Jacquard loom machine, in which the weaving process primarily consists of four steps: weft insertion, beating up, weaving and taking up. Dynamic Weaving Process Simulation simulates these steps according to the underlying loom kinematics and kinetics. First, a weft yarn moves to the fell position under displacement constraints, followed by a beating-up action performed by reed elements. Warp yarns then change positions according to the yarn interlacing pattern defined by a weaving matrix, and taking-up action is simulated to collect woven fabric for continuous weaving process simulation. A Jacquard loom machine individually controls each warp yarn for maximum flexibility of warp motion, managed by the weaving matrix in simulation. Constant boundary tension is implemented to simulate the spring at each warp end. In addition, process simulation adopts re-mesh function to store woven fabric and add new weft yarns for continuous weaving simulation. Dynamic Weaving Process Simulation fully models loom kinetics and kinematics involved in the weaving process. However, the step-by-step simulation of the 3D weaving process requires additional calculation time and computer resource. In order to promote simulation efficiency, enable finer yarn discretization and improve accuracy of fabric micro geometry, parallel computing is implemented in this research and efficiency promotion is presented in this dissertation. The Dynamic Weaving Process Simulation model links fabric micro-geometry with the manufacturing process, allowing determination of weavability of specific weaving pattern and process design. Effects of various weaving process parameters on fabric micro-geometry, fabric mechanical properties and weavability can be investigated with the simulation method.
Sii, How Bing (Perry). "Three-dimensional finite element analysis of concrete pavement on weak foundation." Thesis, Griffith University, 2015. http://hdl.handle.net/10072/366517.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
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Syrový, Jiří. "Analýza trojrozměrných objektů metodou konečných prvků v časové oblasti." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219117.
Full textChenel, Audrey. "Morphological and mechanical characterization of the human liver to improve a finite element model." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0721/document.
Full textIn road accidents, lesions of the abdomen are life-threatening, and require a long and expensive medical treatment. It is important to offer a better prevention of traumatic abdominal injuries. Numerical models of the human body have been developed to understand the mechanisms of injury. The aim of this thesis is to contribute to the development of a numerical model of human liver for the prediction of liver lesions in case of shock.First, a morphological characterization of the liver was performed on 78 healthy patient scanners and highlight the existence of 4 morphotypes.Then, experiments were carried out to highlight the influence of this pressurization of the vessels on the strain state of the Glisson capsule and to identify the local ultimate strain during an impact.Finally, the numerical models of the 4 identified morphotypes were constructed and used to simulate the deceleration tests performed in the experimental part
Hong, Jung-Pyo. "Three-dimensional nonlinear finite element model for single and multiple dowel-type wood connections." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/364.
Full textYan, Kaidi. "The Abaqus/CAE Plug-in for Premium Threaded connection 3D parameter Finite Element Model." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78245.
Full textMaster of Science
Harich, Jens. "Theorie und Numerik unidirektional verstärkter Faserverbundwerkstoffe 3D Finite-Element-Untersuchungen der Faser-Matrix Mikroinstabilitäten /." [S.l. : s.n.], 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000007982.
Full textFeng, Huan. "3D-models of railway track for dynamic analysis." Thesis, KTH, Transportvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-52619.
Full textGomes, Érica Alves [UNESP]. "Estudo do desajuste angular e vertical em próteses fixas implantossuportadas por meio do MEF-3D." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/105579.
Full textObjetivo: A análise pelo método dos elementos finitos tridimensional foi utilizada para avaliar o efeito dos desajustes angular e vertical simulado em próteses fixas implantossuportadas parafusadas de 3 elementos, na resposta biomecânica do tecido ósseo peri-implantar, implantes e componentes protéticos. Material e método: Foram confeccionados 4 modelos tridimensionais, representativos de secção mandibular direita contendo um implante na região de segundo pré-molar (2oPM) e outro na região de segundo molar (2oM) ferulizados por uma prótese metalocerâmica implantossuportada parafusada de 3 elementos, diferenciados pelo tipo de desajuste protético, gerando os grupos: GC (grupo controle) - prótese totalmente adaptada aos implantes, DAU (desajuste angular unilateral) - prótese com desajuste angular unilateral de 100μm na região mesial do 2oM, DVU (desajuste vertical unilateral) - prótese com desajuste vertical unilateral de 100μm na região mesial do 2oM e DVT (desajuste vertical total) - prótese com desajuste vertical de 100μm em toda a plataforma de assentamento da infraestrutura no 2oM. Com a utilização do programa de elementos finitos Ansys® uma força vertical total de 400N foi distribuída em 12 pontos de parada cêntrica, sendo que cada molar recebeu um carregamento total de 150N e o 2oPM de 100N, gerando mapas de tensões. Resultados: Verificou-se que a distribuição e os valores de tensões para o tecido ósseo peri-implantar foram similares para todos os grupos. Os grupos com desajustes alteraram o padrão de distribuição e elevaram a magnitude das tensões em relação ao grupo GC. No grupo DAU os maiores valores de tensões foram observados no corpo do implante e parafuso de retenção. Já nos grupos DVU e DVT elevados valores de tensões foram encontrados na plataforma de assentamento da infraestrutura...
Purpose: The three-dimensional finite element analysis was used to evaluate the effect of vertical and angular misfit in 3-piece implant-supported and screw-retained fixed prostheses on biomechanical response in peri-implant bone tissue, implants and prosthetic components. Material and method: Four three-dimensional models were fabricated to represent a right posterior mandibular section with one implant in the region of second premolar (2°PM) and other in the region of second molar (2°M). The implants were splinted by a 3- piece implant-supported metal ceramic prosthesis and differed according to the type of misfit as represented by the groups: CG (control group) - prosthesis with complete fit to the implants, UAM (unilateral angular misfit) – prosthesis presenting unilateral angular misfit of 100μm in the mesial region of the 2°M, UVM (unilateral vertical misfit) – prosthesis presenting unilateral vertical misfit of 100μm in the mesial region of the 2°M, and TVM (total vertical misfit) – prosthesis presenting total vertical misfit of 100μm in the platform of the framework in the 2°M. A vertical load of 400N was distributed and applied on 12 centric points by the software Ansys®. So, vertical loading of 150N was applied on each molar while vertical load of 100N was applied on the 2°PM. Stress maps were obtained by processing of the finite element software. Results: The stress values and distribution on peri-implant bone tissue were similar for all groups. The groups presenting misfit exhibited different distribution pattern and increased stress magnitude in comparison to the group CG. The highest stress values in group UAM were observed in the implant body and retention screw. The groups UVM and TVM exhibited high stress values in the platform of the framework... (Complete abstract click electronic access below)
Priadi, Eka. "Behaviour of Tiang Tongkat foundation over Pontianak soft organic soil using 3D-finite element analysis." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:bsz:105-081293.
Full textGreene, Robert Matthew. "Finite element simulation and die shape optimisation method applied to forging of 3D aerofoil blades." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485072.
Full textLiu, Zhanqiu. "BIVENTRICULAR FINITE ELEMENT MODELING AND QUANTIFICATION OF 3D LANGRAGIAN STRAINS AND TORSION USING DENSE MRI." UKnowledge, 2016. http://uknowledge.uky.edu/me_etds/80.
Full textLantoine, Rémi. "A 3D sliding bearing finite element based on the Bouc-Wen model : Implementation in Abaqus." Thesis, KTH, Bro- och stålbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280479.
Full textAndrš, David. "Adaptive hp-FEM for elliptic problems in 3D on irregular meshes." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Full textMeléndez, Gimeno Carlos. "A finite element-based approach for the analysis and design of 3D reinforced concrete elements and its applications to D-regions." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/86193.
Full textEl método de los elementos finitos es una potente herramienta de análisis que ha facilitado un mejor conocimiento del comportamiento de las estructuras de hormigón armado. Su uso en el ámbito de la investigación está ampliamente extendido. Su aplicación en la práctica ingenieril ha permitido la resolución de elementos complejos. Sin embargo, el ingeniero estructural común todavía es reticente a usar la modelización por elementos finitos ya que considera que la mayoría de estos modelos son excesivamente sofisticados para sus necesidades. La complejidad de muchas herramientas de elementos finitos suele derivarse de la adopción de modelos constitutivos de hormigón avanzados. La implementación de modelos más sencillos podría facilitar su uso por usuarios menos experimentados. En la práctica ingenieril el análisis con elementos finitos puede ser de gran utilidad para tratar aquellos elementos más problemáticos y/o donde la aplicación de los métodos de análisis tradicionales presenta limitaciones. Esto incluye las llamadas regiones D con comportamiento 3D. El método de bielas y tirantes y el método de campos de tensiones son herramientas racionales para el análisis y dimensionamiento de regiones D, pero su extensión a 3D es problemática. Este hecho explica por qué se adoptan todavía hipótesis excesivamente conservadoras en el dimensionamiento de estos elementos. La propuesta de métodos analíticos y de diseño más adecuados o la modelización con elementos finitos podría conducir a soluciones más racionales, lo que a su vez reduciría las necesidades de material y los costes. Como parte de esta tesis se ha desarrollado una herramienta de cálculo no lineal basada en el método de los elementos finitos orientada al análisis y dimensionamiento de regiones D tridimensionales por usuarios con menos experiencia en la modelización con elementos finitos. Se ha adoptado un modelo ortotrópico para el hormigón para permitir el uso de relaciones uniaxiales de tensión-deformación. Sólo es necesario definir un único parámetro, la resistencia a compresión uniaxial del hormigón. Adicionalmente, se han implementado varias funciones de ayuda, entre las que destacan: un modelo de armadura embebida para facilitar la introducción de geometrías de armado complejas; elementos especiales de apoyo y de carga que permiten un tratamiento integral de las condiciones de contorno; y un algoritmo de diseño para la determinación automática del área de armado necesaria. Se presentan tres ejemplos de aplicación a regiones D 3D representativas para mostrar las capacidades de la herramienta. En concreto, en la tercera parte del documento se describen los análisis de catorce encepados, tres cálices de cimentación y un bloque de anclaje. Los resultados muestran que se pueden obtener predicciones bastante realistas considerando modelos constitutivos relativamente sencillos. También se demuestra la capacidad de la herramienta para configurar modelos de campo de tensiones consistentes dependiendo de la configuración de armado. Además se muestra la capacidad del algoritmo de diseño para configurar disposiciones de armado racionales. En la cuarta parte se propone un método para el análisis y dimensionamiento de encepados sobre cuatro pilotes con geometría rectangular. El método se basa en un modelo 3D de bielas y tirantes refinado y la consideración de tres modos de fallo posibles: rotura del acero, aplastamiento de la biela diagonal en la base de la columna con estrechamiento de la misma y splitting de la biela diagonal debido a la fisuración transversal. La principal novedad es que el ángulo de la biela no se fija como en otros modelos, sino que se determina mediante la maximización de la resistencia del encepado. El método considera el debilitamiento de la resistencia del hormigón fisurado, condiciones de compatibilidad de deformaciones y detalles de armado. Su aplicación a 162 especímenes dio luga
El mètode dels elements finits és una potent eina d'anàlisi que ha facilitat un millor coneixement del comportament de les estructures de formigó armat. El seu ús en l'àmbit de la investigació està àmpliament estès. La seua aplicació en la pràctica enginyeril ha permès la resolució d'elements més complexos. No obstant això, l'enginyer estructural comú encara és reticent a fer servir la modelització per elements finits ja que considera que la majoria d'aquests models són excessivament sofisticats per a les seues necessitats i el seu conèixement. En concret, la complexitat de moltes eines d'elements finits sol derivar-se de l'adopció de models constitutius avançats de formigó. La implementació de models més senzills basats en la pràctica enginyeril podria facilitar el seu ús per a usuaris menys experimentats en la modelització amb elements finits. A la pràctica enginyeril l'anàlisi amb elements finits pot ser de gran utilitat per a tractar aquells elements més problemàtics i/o on l'aplicació dels mètodes d'anàlisi tradicionals presenta limitacions. Això inclou les anomenades regions D amb comportament 3D. El mètode de bieles i tirants i el mètode de camps de tensions són eines racionals per a l'anàlisi i dimensionament de regions D, però la seua extensió a 3D és problemàtica. Aquest fet explica per què s'adopten encara hipòtesis excessivament conservadores en el dimensionament d'aquests elements. La proposta de mètodes analítics i de disseny més adequats o la modelització amb elements finits podria conduir a solucions més racionals, amb el que també es reduirien les necessitats de material i els costos. Com a part d'aquesta tesi s'ha desenvolupat una eina de càlcul no lineal basada en el mètode dels elements finits orientada a l'anàlisi i dimensionament de regions D tridimensionals per a usuaris amb menys experiència en la modelització amb elements finits. S'ha adoptat un model ortotròpic per al formigó per permetre l'ús de relacions uniaxials de tensió-deformació. Només cal definir un únic paràmetre, la resistència a compressió uniaxial del formigó. Addicionalment, s'han implementat diverses funcions d'ajuda, entre les quals destaquen: un model d'armadura embeguda per facilitar la introducció de geometries d'armat complexes; elements especials de suport i de càrrega que permeten un tractament integral i senzill de les condicions de contorn; i un algoritme de disseny per a la determinació automàtica de l'àrea d'armat necessari. Es presenten tres exemples d'aplicació a regions D 3D representatives per mostrar les capacitats de l'eina. En particular, en la tercera part del document es descriuen les anàlisis de catorze enceps sobre quatre pilons, 3 calzes de fonamentació i un bloc d'ancoratge. Els resultats mostren que es poden obtenir prediccions prou realistes considerant models constitutius relativament senzills. També es demostra la capacitat de l'eina per configurar models de camp de tensions consistents depenent de la configuració d'armat. A més es mostra la capacitat de l'algoritme de disseny per configurar disposicions d'armat racionals. En la quarta part es proposa un mètode per a l'anàlisi i dimensionament d'enceps sobre quatre pilons amb geometria rectangular. El mètode es basa en un model 3D de bieles i tirants refinat i la consideració de tres modes de fallada possibles: trencament de l'acer, aixafament de la biela diagonal a la base de la columna amb estrenyiment de la mateixa i splitting de la biela diagonal per causa de la fissuració transversal. La principal novetat és que l'angle de la biela no es fixa com en els models actuals de bieles i tirants, sinó que es determina mitjan\c{c}ant la maximització de la resistència de l'encep. El mètode proposat considera el debilitament de la resistència del formigó fissurat, condicions de compatibilitat de deformacions i detalls d'armat. La seua aplicació a 162 espècimens de la liter
Meléndez Gimeno, C. (2017). A finite element-based approach for the analysis and design of 3D reinforced concrete elements and its applications to D-regions [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86193
TESIS
Simsir, Caner. "3d Finite Element Simulation Of Steel Quenching In Order To Determine The Microstructure And Residual Stresses." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609412/index.pdf.
Full textby user subroutines. The accuracy of the model was verified by simulating the quenching of eccentrically drilled steel cylinders. Simulation results were justified via SEM observations and XRD residual stress measurements. According to the results, the model can effectively predict the trends in the distribution of microstructure and residual stresses with a remarkable accuracy.
Pradhan, Dhruba Lal. "Development of P-Y Curves for Monopiles in Clay using Finite Element Model Plaxis 3D Foundation." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bygg, anlegg og transport, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18693.
Full textRumpler, Romain. "Efficient Finite Element Approach for Structural-Acoustic Applications including 3D modelling of Sound Absorbing Porous Materials." Doctoral thesis, KTH, MWL Numerisk akustik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-90335.
Full textDans le contexte de lutte contre les nuisances sonores, cette thèse porte sur le développement de méthodes de résolution efficaces par éléments finis, pour des problèmes de vibroacoustique interne avec interfaces dissipatives, dans le domaine des basses fréquences. L’étude se limite à l’utilisation de solutions passives telles que l’intégration de matériaux poreux homogènes et isotropes, modélisés par une approche fondée sur la théorie de Biot-Allard. Ces modèles étant coûteux en terme de résolution, un des objectifs de cette thèse est de proposer une approche modale pour la réduction du problème poroélastique, bien que l’adéquation d’une telle approche avec le comportement dynamique des matériaux poreux soit à démontrer.Dans un premier temps, la résolution de problèmes couplés élasto-poro-acoustiques par sous-structuration dynamique des domaines acoustiques et poreux est établie. L’approche modale originale proposée pour les milieux poroélastiques, ainsi qu’une procédure de sélection des modes significatifs, sont validées sur des exemples 1D à 3D.Une deuxième partie présente une méthode combinant l’utilisation des modèles réduits précédemment établis avec une procédure d’approximation de solution par approximants de Padé. Il est montré qu’une telle combinaison offre la possibilité d’accroître les performances de la résolution (allocation mémoire et ressources en temps de calcul).Un chapitre dédié aux applications permet d’évaluer et comparer les approches sur un problème académique 3D, mettant en valeur leurs performances encourageantes. Afin d’améliorer les méthodes établies dans cette thèse, des perspectives à ces travaux de recherche sont apportées en conclusion.
QC 20120224
FP6 Marie-Curie Smart Structures
FP7 Marie-Curie Mid-Frequency
Harich, Jens [Verfasser]. "Theorie und Numerik unidirektional verstärkter Faserverbundwerkstoffe : 3D-Finite-Element-Untersuchungen der Faser-Matrix-Mikroinstabilitäten / Jens Harich." Karlsruhe : Inst. für Baustatik, 2008. http://d-nb.info/998331708/34.
Full textRumpler, Romain. "Efficient finite element approach for structural-acoustic applicationns including 3D modelling of sound absorbing porous materials." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2012. http://tel.archives-ouvertes.fr/tel-00726915.
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