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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Phenomenological Swelling Model of Battery Module / Fenomenologisk svällningsmodell för batterimoduler

Lakshmipuram Govindaraj, Abhiram January 2022 (has links)
Lithium-ion batteries (LiBs) are the most popular choice in the shift towardselectrification due to their high volumetric energy and power density. An importantaspect to study is the effect of swelling on the mechanical performance of LiBsas it plays an important role in determining the forces in the battery module.During charge/discharge a battery cell swells/shrinks and over the lifetime of thebattery, swelling becomes permanent. The swelling increases with cycling that causesincreasing forces in the module. Excessive pressure generated due to cycling in themodule may electrically short the cells and/or cause mechanical damage to the cells.Compression pads placed between cells in the battery module absorb the swelling. Thematerial properties and size of the compression pads used influence the module forcesat End of Life (EoL).In this study, a 1D phenomenological model is built to predict the swelling forces. Themodel differs from others in literature in a way that the swelling forces are predictedwith cycling rather than State of Charge (SoC) and a stress-strain based constitutivemodel is used rather than a spring model. A process to eliminate the need for multipletests is also proposed in the thesis to predict swelling forces for different compressionpads and preloads.The proposed model is relatively simple and can improve existing battery managementsystems by predicting the swelling and the magnitude of swelling forces for differentcompression pads and preloads during the operational life of the battery.
22

Nyutveckling av Huddigs spakkonsoler för modellerna 1060 och 1260

Larsson, Kristoffer January 2008 (has links)
<p>Sammanfattning</p><p>Författaren Kristoffer Larsson har skrivit rapporten tillsammans med grävlastarstillverkaren Huddig i Hudiksvall. Rapporten beskriver nyutvecklingen av Huddigs spakkonsoler. Bakgrunden till examensarbetet är att Huddig har haft kontinuerlig utveckling av sin interiör och hytt men spakkonsolerna har inte följt med i den utvecklingen. Målet med examensarbetet var att ta fram fyra olika prototyper med hänsyn på utformning, handergonomi, knapplacering, trängstyrningsfunktion, rototilt, materialval och tillverkningsmetod.</p><p>För att författaren skulle få en bild av vad det fanns för kundsynpunkter och vad andra personen som har en relation till Huddig har för synpunkter gjordes en marknadsundersökning. Därefter följde arbetet med att bryta ned arbetet och produkten i delar med olika metoder.</p><p>Åtta olika konceptförslag skissades fram och slutligen sållades sex olika delar från koncepten fram. En grupp från Huddig och författaren Kristoffer Larsson tyckte dessa delar var bäst lämpade att gå vidare med. De delar som gick vidare var:</p><p>− Konisk underdel</p><p>− Kantig form</p><p>− Dubbla rader med knappar på vänster konsol</p><p>− Utåtlutande trängstyrning</p><p>− Fram/back utåtlutande</p><p>− Tvåhandsgrepp för trängstyrningen</p><p>− Placering av stödbensreglage</p><p>Utifrån dessa kommentarer och synpunkter på de framsållade koncepten skissade författaren fram fyra koncept som valdes att göras prototyper av. Skälet till att prototyper valdes att tillverkas var att det är svårt att känna och testa om ett koncept verkligen fungerar eller inte genom att bara kolla på en skiss.</p><p>Målet med examensarbetet var att generera fram unika koncept men även att tillverka prototyper av dem, vilket uppnåddes. Utifrån resultat av denna rapport och prototyperna kan Huddig fortsätta att utveckla spakkonsolerna till en genomtänkt och smart lösning.</p> / <p>Abstract</p><p>The author Kristoffer Larsson wrote this examinations paper for the excavator loader company Huddig AB in Hudiksvall. The subject for this bachelor’s thesis is development of joystick pads at Huddig. The background for the bachelor's thesis is that Huddig have been during the last years developed and redesigning the interior of the cabin. The problem is that the joystick brackets haven’t followed the same development. The goal with this bachelor's thesis is to develop and manufacture four prototypes with consideration on design, ergonomics, bottom positions, control of steering, rototilt, choice of material and manufacturing method.</p><p>To get a picture of what the drivers want and theirs aspect of the development of the joysticks pads the author did a market research with Huddigs customers. After the market research was done some methods and functions solving methods was used to break down the product to different functions.</p><p>Eight different concepts were generated and the finial concepts were selected of a group from Huddig and Kristoffer Larsson. They selected the concepts because they taught that they were best suited to manufacture prototypes of. These are the subjects of the concepts:</p><p>− Conic underpart</p><p>− Angular design</p><p>− Double rows with bottoms at left bracket</p><p>− Tilted steering control</p><p>− Tilted transport direction shifter</p><p>− Two hand grip for steering</p><p>− Placement of hydraulic lifters</p><p>From these comments and aspects the author drew four sketches to have as guidelines for the prototypes. The reason to make prototypes was that it is hard to anticipate if a concept works in the real life based from a sketch.</p><p>The goal with this bachelor's thesis was to design and manufacture innovated concepts which have been done. From the result of the bachelor's thesis Huddig can use it to continue to develop the joystick brackets to a successful product.</p>
23

Nyutveckling av Huddigs spakkonsoler för modellerna 1060 och 1260

Larsson, Kristoffer January 2008 (has links)
Sammanfattning Författaren Kristoffer Larsson har skrivit rapporten tillsammans med grävlastarstillverkaren Huddig i Hudiksvall. Rapporten beskriver nyutvecklingen av Huddigs spakkonsoler. Bakgrunden till examensarbetet är att Huddig har haft kontinuerlig utveckling av sin interiör och hytt men spakkonsolerna har inte följt med i den utvecklingen. Målet med examensarbetet var att ta fram fyra olika prototyper med hänsyn på utformning, handergonomi, knapplacering, trängstyrningsfunktion, rototilt, materialval och tillverkningsmetod. För att författaren skulle få en bild av vad det fanns för kundsynpunkter och vad andra personen som har en relation till Huddig har för synpunkter gjordes en marknadsundersökning. Därefter följde arbetet med att bryta ned arbetet och produkten i delar med olika metoder. Åtta olika konceptförslag skissades fram och slutligen sållades sex olika delar från koncepten fram. En grupp från Huddig och författaren Kristoffer Larsson tyckte dessa delar var bäst lämpade att gå vidare med. De delar som gick vidare var: − Konisk underdel − Kantig form − Dubbla rader med knappar på vänster konsol − Utåtlutande trängstyrning − Fram/back utåtlutande − Tvåhandsgrepp för trängstyrningen − Placering av stödbensreglage Utifrån dessa kommentarer och synpunkter på de framsållade koncepten skissade författaren fram fyra koncept som valdes att göras prototyper av. Skälet till att prototyper valdes att tillverkas var att det är svårt att känna och testa om ett koncept verkligen fungerar eller inte genom att bara kolla på en skiss. Målet med examensarbetet var att generera fram unika koncept men även att tillverka prototyper av dem, vilket uppnåddes. Utifrån resultat av denna rapport och prototyperna kan Huddig fortsätta att utveckla spakkonsolerna till en genomtänkt och smart lösning. / Abstract The author Kristoffer Larsson wrote this examinations paper for the excavator loader company Huddig AB in Hudiksvall. The subject for this bachelor’s thesis is development of joystick pads at Huddig. The background for the bachelor's thesis is that Huddig have been during the last years developed and redesigning the interior of the cabin. The problem is that the joystick brackets haven’t followed the same development. The goal with this bachelor's thesis is to develop and manufacture four prototypes with consideration on design, ergonomics, bottom positions, control of steering, rototilt, choice of material and manufacturing method. To get a picture of what the drivers want and theirs aspect of the development of the joysticks pads the author did a market research with Huddigs customers. After the market research was done some methods and functions solving methods was used to break down the product to different functions. Eight different concepts were generated and the finial concepts were selected of a group from Huddig and Kristoffer Larsson. They selected the concepts because they taught that they were best suited to manufacture prototypes of. These are the subjects of the concepts: − Conic underpart − Angular design − Double rows with bottoms at left bracket − Tilted steering control − Tilted transport direction shifter − Two hand grip for steering − Placement of hydraulic lifters From these comments and aspects the author drew four sketches to have as guidelines for the prototypes. The reason to make prototypes was that it is hard to anticipate if a concept works in the real life based from a sketch. The goal with this bachelor's thesis was to design and manufacture innovated concepts which have been done. From the result of the bachelor's thesis Huddig can use it to continue to develop the joystick brackets to a successful product.
24

Particionamento de células e pads de I/O em circuitos VLSI 3D / Cells and I/O pads partitioning targeting 3d vlsi integrated circuits

Sawicki, Sandro January 2009 (has links)
A etapa de particionamento em circuitos VLSI 3D é fundamental na distribuição de células e blocos para as camadas do circuito, além de auxiliar na redução da complexidade dos posicionadores. Estes, quando o particionamento é bem realizado, permitem que se atinjam soluções com menor comprimento total de fios, o que reduz a dissipação de potência e aumenta o desempenho dos circuitos. Atualmente, os algoritmos utilizados para resolver o problema de particionamento em circuitos 3D são adaptações daqueles aplicados em circuitos planares. Ou seja, o circuito é particionado como se fosse um hipergrafo tradicional, e as células são assinaladas diretamente para as partições, com o objetivo de reduzir somente as conexões que cruzam as partes. Contudo essa solução é simplista e faz com que o algoritmo não perceba a criação de conexões longas, o que aumenta o número de vias do circuito e, consequentemente, sua área. É importante compreender que o valor dos recursos usados é um múltiplo da distância vertical das camadas. Na verdade, considerando-se que o caminho de uma camada para outra adjacente atravessa todos os níveis de metal, é evidente que qualquer ligação vertical superior à adjacente pode ser proporcionalmente mais custosa para o roteamento, sem mencionar o atraso provocado e o quanto da área ativa é ocupada. Em vista disso, este trabalho apresenta um conjunto de algoritmos desenvolvidos para reduzir o número de vias em circuitos VLSI 3D. A otimização é obtida pelo uso de duas estratégias distintas: a análise prévia da estrutura interna do circuito e a redução do número de conexões verticais não-adjacentes. Os algoritmos propostos, além de reduzir o número de vias-3D, adaptam a lógica dos circuitos 2D para os 3D mantendo o balanceamento de área e dos pinos de I/O entre as diferentes camadas. Os resultados experimentais mostram que essas técnicas reduzem o número total de vias-3D em 19%, 18%, 12% e 16% em duas, três, quatro e cinco tiers, respectivamente, comparados com os resultados das abordagens atuais. / A 3D circuit is the stacking of regular 2D circuits. The advances on the fabrication and packaging technologies allow interconnection of stacked 2D circuits. However, 3D-vias can impose significant obstacles and constraints to the 3D placement problem. Most of the existing placement and partitioning algorithms completely ignore this fact, but they do optimize the number of vias using a min-cut partitioning applied to a generic graph partitioning problem. This work proposes a new approach for I/O pads and cells partitioning addressing 3D-vias reduction and its impact on the 3D circuit design. The approach presents two distinct strategies: the first one is based on circuit structure analyses and the second one reducing the number of connections between nonadjacent tiers. The strategies outperformed a state-of-the-art hypergraph partitioner, hMetis and other approaches by providing a reduction of the number of 3D-vias 19%, 17%, 12% and 16% using two, three, four and five tiers.
25

Particionamento de células e pads de I/O em circuitos VLSI 3D / Cells and I/O pads partitioning targeting 3d vlsi integrated circuits

Sawicki, Sandro January 2009 (has links)
A etapa de particionamento em circuitos VLSI 3D é fundamental na distribuição de células e blocos para as camadas do circuito, além de auxiliar na redução da complexidade dos posicionadores. Estes, quando o particionamento é bem realizado, permitem que se atinjam soluções com menor comprimento total de fios, o que reduz a dissipação de potência e aumenta o desempenho dos circuitos. Atualmente, os algoritmos utilizados para resolver o problema de particionamento em circuitos 3D são adaptações daqueles aplicados em circuitos planares. Ou seja, o circuito é particionado como se fosse um hipergrafo tradicional, e as células são assinaladas diretamente para as partições, com o objetivo de reduzir somente as conexões que cruzam as partes. Contudo essa solução é simplista e faz com que o algoritmo não perceba a criação de conexões longas, o que aumenta o número de vias do circuito e, consequentemente, sua área. É importante compreender que o valor dos recursos usados é um múltiplo da distância vertical das camadas. Na verdade, considerando-se que o caminho de uma camada para outra adjacente atravessa todos os níveis de metal, é evidente que qualquer ligação vertical superior à adjacente pode ser proporcionalmente mais custosa para o roteamento, sem mencionar o atraso provocado e o quanto da área ativa é ocupada. Em vista disso, este trabalho apresenta um conjunto de algoritmos desenvolvidos para reduzir o número de vias em circuitos VLSI 3D. A otimização é obtida pelo uso de duas estratégias distintas: a análise prévia da estrutura interna do circuito e a redução do número de conexões verticais não-adjacentes. Os algoritmos propostos, além de reduzir o número de vias-3D, adaptam a lógica dos circuitos 2D para os 3D mantendo o balanceamento de área e dos pinos de I/O entre as diferentes camadas. Os resultados experimentais mostram que essas técnicas reduzem o número total de vias-3D em 19%, 18%, 12% e 16% em duas, três, quatro e cinco tiers, respectivamente, comparados com os resultados das abordagens atuais. / A 3D circuit is the stacking of regular 2D circuits. The advances on the fabrication and packaging technologies allow interconnection of stacked 2D circuits. However, 3D-vias can impose significant obstacles and constraints to the 3D placement problem. Most of the existing placement and partitioning algorithms completely ignore this fact, but they do optimize the number of vias using a min-cut partitioning applied to a generic graph partitioning problem. This work proposes a new approach for I/O pads and cells partitioning addressing 3D-vias reduction and its impact on the 3D circuit design. The approach presents two distinct strategies: the first one is based on circuit structure analyses and the second one reducing the number of connections between nonadjacent tiers. The strategies outperformed a state-of-the-art hypergraph partitioner, hMetis and other approaches by providing a reduction of the number of 3D-vias 19%, 17%, 12% and 16% using two, three, four and five tiers.
26

Estudo de variáveis de composição e processo para controle da compressibilidade

Menetrier, Ademir Reus 11 December 2006 (has links)
Pastilhas de freio para sistemas de freios automotivos correspondem a um dos materiais compósitos mais complexos já que eles contêm muitos componentes, cada qual com uma grande variedade de propriedades físicas e químicas. Esta natureza multi-fase é necessária para satisfazer a grande variedade de demandas relativas à performance. As condições de processamento também possuem grande influência nas propriedades deste complexo compósito. As pastilhas de freio usadas neste trabalho foram sem amianto do tipo semi-metálica contendo muitos elementos, incluindo resina fenólica, fibra de reforço, lubrificantes sólidos, abrasivos e cargas. Este trabalho tem como objetivo principal esclarecer a influência entre as variáveis de processo e de composição nas propriedades de compressibilidade a frio, densidade, dureza, flexão e coeficiente de atrito. Para isso foram utilizados planejamentos de experimentos fracionados e completos. O planejamento de experimentos fracionado, 25-1, indicou que a quantidade de resina fenólica e a temperatura do molde são os fatores mais significativos para a compressibilidade. O planejamento de experimentos completo, 24, mostrou mais uma vez, que a quantidade de resina e a temperatura do molde, bem como as suas interações, são fatores significativos na determinação da compressibilidade. O terceiro planejamento de experimentos, 2³, concentrou-se nas propriedades da resina, já que a mesma mostrou-se muito influente na determinação das propriedades dos materiais de atrito. Os resultados mostraram que é possível controlar as propriedades tribológicas e a compressibilidade das pastilhas de freio dentro de certa escala de valores. Assim, este trabalho mostra que é possível aplicar técnicas estatísticas para racionalizar o projeto de materiais de atrito. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-14T18:07:18Z No. of bitstreams: 1 Dissertacao Ademir R Menetrier.pdf: 3142797 bytes, checksum: 973f28293a5f77372f68c6146e790438 (MD5) / Made available in DSpace on 2014-05-14T18:07:18Z (GMT). No. of bitstreams: 1 Dissertacao Ademir R Menetrier.pdf: 3142797 bytes, checksum: 973f28293a5f77372f68c6146e790438 (MD5) / Brake pads for automotive brake systems represent one of the most complex composite materials since they contain many components with widely varying physical and chemical properties. This multiphase nature is necessary to satisfy a wide variety of performance related demands. Processing conditions also have a major influence on the properties of these complex composites. Brake pads used in these studies were semi-metallic non-asbestos friction materials containing many different ingredients, including phenolic resin, reinforcing fibers, solid lubricants, abrasives and fillers. In this work, the influence of composition and process parameters on the compressibility, density, hardness, flexure strength and coefficient of friction were investigated. The designs of experiments selected for this study were fractional and full varieties. In the initial fractional design of experiments, we found both the quantity of resin and the mold temperature to be dominant influences on the compressibility. A full design of experiments again indicated that the quantity of resin and mold temperature, as well as their interaction, are the dominant players in determining the compressibility. A third design of experiments concentrated on the resin properties since this factor was the most influential in determining the properties of friction materials. The results show that it is possible to control both the tribological properties and the compressibility of the pads within a rather large range of values. Thus, the work shows that it is possible to use statistical methods to rationalize brake pad design.
27

Particionamento de células e pads de I/O em circuitos VLSI 3D / Cells and I/O pads partitioning targeting 3d vlsi integrated circuits

Sawicki, Sandro January 2009 (has links)
A etapa de particionamento em circuitos VLSI 3D é fundamental na distribuição de células e blocos para as camadas do circuito, além de auxiliar na redução da complexidade dos posicionadores. Estes, quando o particionamento é bem realizado, permitem que se atinjam soluções com menor comprimento total de fios, o que reduz a dissipação de potência e aumenta o desempenho dos circuitos. Atualmente, os algoritmos utilizados para resolver o problema de particionamento em circuitos 3D são adaptações daqueles aplicados em circuitos planares. Ou seja, o circuito é particionado como se fosse um hipergrafo tradicional, e as células são assinaladas diretamente para as partições, com o objetivo de reduzir somente as conexões que cruzam as partes. Contudo essa solução é simplista e faz com que o algoritmo não perceba a criação de conexões longas, o que aumenta o número de vias do circuito e, consequentemente, sua área. É importante compreender que o valor dos recursos usados é um múltiplo da distância vertical das camadas. Na verdade, considerando-se que o caminho de uma camada para outra adjacente atravessa todos os níveis de metal, é evidente que qualquer ligação vertical superior à adjacente pode ser proporcionalmente mais custosa para o roteamento, sem mencionar o atraso provocado e o quanto da área ativa é ocupada. Em vista disso, este trabalho apresenta um conjunto de algoritmos desenvolvidos para reduzir o número de vias em circuitos VLSI 3D. A otimização é obtida pelo uso de duas estratégias distintas: a análise prévia da estrutura interna do circuito e a redução do número de conexões verticais não-adjacentes. Os algoritmos propostos, além de reduzir o número de vias-3D, adaptam a lógica dos circuitos 2D para os 3D mantendo o balanceamento de área e dos pinos de I/O entre as diferentes camadas. Os resultados experimentais mostram que essas técnicas reduzem o número total de vias-3D em 19%, 18%, 12% e 16% em duas, três, quatro e cinco tiers, respectivamente, comparados com os resultados das abordagens atuais. / A 3D circuit is the stacking of regular 2D circuits. The advances on the fabrication and packaging technologies allow interconnection of stacked 2D circuits. However, 3D-vias can impose significant obstacles and constraints to the 3D placement problem. Most of the existing placement and partitioning algorithms completely ignore this fact, but they do optimize the number of vias using a min-cut partitioning applied to a generic graph partitioning problem. This work proposes a new approach for I/O pads and cells partitioning addressing 3D-vias reduction and its impact on the 3D circuit design. The approach presents two distinct strategies: the first one is based on circuit structure analyses and the second one reducing the number of connections between nonadjacent tiers. The strategies outperformed a state-of-the-art hypergraph partitioner, hMetis and other approaches by providing a reduction of the number of 3D-vias 19%, 17%, 12% and 16% using two, three, four and five tiers.
28

Estudo de variáveis de composição e processo para controle da compressibilidade

Menetrier, Ademir Reus 11 December 2006 (has links)
Pastilhas de freio para sistemas de freios automotivos correspondem a um dos materiais compósitos mais complexos já que eles contêm muitos componentes, cada qual com uma grande variedade de propriedades físicas e químicas. Esta natureza multi-fase é necessária para satisfazer a grande variedade de demandas relativas à performance. As condições de processamento também possuem grande influência nas propriedades deste complexo compósito. As pastilhas de freio usadas neste trabalho foram sem amianto do tipo semi-metálica contendo muitos elementos, incluindo resina fenólica, fibra de reforço, lubrificantes sólidos, abrasivos e cargas. Este trabalho tem como objetivo principal esclarecer a influência entre as variáveis de processo e de composição nas propriedades de compressibilidade a frio, densidade, dureza, flexão e coeficiente de atrito. Para isso foram utilizados planejamentos de experimentos fracionados e completos. O planejamento de experimentos fracionado, 25-1, indicou que a quantidade de resina fenólica e a temperatura do molde são os fatores mais significativos para a compressibilidade. O planejamento de experimentos completo, 24, mostrou mais uma vez, que a quantidade de resina e a temperatura do molde, bem como as suas interações, são fatores significativos na determinação da compressibilidade. O terceiro planejamento de experimentos, 2³, concentrou-se nas propriedades da resina, já que a mesma mostrou-se muito influente na determinação das propriedades dos materiais de atrito. Os resultados mostraram que é possível controlar as propriedades tribológicas e a compressibilidade das pastilhas de freio dentro de certa escala de valores. Assim, este trabalho mostra que é possível aplicar técnicas estatísticas para racionalizar o projeto de materiais de atrito. / Brake pads for automotive brake systems represent one of the most complex composite materials since they contain many components with widely varying physical and chemical properties. This multiphase nature is necessary to satisfy a wide variety of performance related demands. Processing conditions also have a major influence on the properties of these complex composites. Brake pads used in these studies were semi-metallic non-asbestos friction materials containing many different ingredients, including phenolic resin, reinforcing fibers, solid lubricants, abrasives and fillers. In this work, the influence of composition and process parameters on the compressibility, density, hardness, flexure strength and coefficient of friction were investigated. The designs of experiments selected for this study were fractional and full varieties. In the initial fractional design of experiments, we found both the quantity of resin and the mold temperature to be dominant influences on the compressibility. A full design of experiments again indicated that the quantity of resin and mold temperature, as well as their interaction, are the dominant players in determining the compressibility. A third design of experiments concentrated on the resin properties since this factor was the most influential in determining the properties of friction materials. The results show that it is possible to control both the tribological properties and the compressibility of the pads within a rather large range of values. Thus, the work shows that it is possible to use statistical methods to rationalize brake pad design.
29

Analyse dynamique d'une ligne d'arbre verticale supportée par une butée à patins oscillants / Dynamic analysis of a vertical turbine supported by a tilting pads thrust bearing

Denis, Sébastien 19 December 2014 (has links)
Les problèmes vibratoires sont l'une des principales causes des maintenances effectuées sur les turbines de barrages hydroélectrique en France. Dans cette thèse CIFRE, subventionnée par la Division Technique Générale d’Électricité de France à Grenoble, nous voulons étudier numériquement les phénomènes physiques en jeu.Pour cela, chaque partie composant ce type de machine tournante est modélisée : la ligne d'arbre, les accouplements rigides, les paliers hydrodynamiques, la butée hydrodynamique à patins oscillants, les étanchéités et les efforts électromagnétiques. Celui du rotor est basé sur une approche classique 1D, prenant en compte des défauts d'accouplement rigide. Les paliers hydrodynamiques peuvent être alimentés par des rainures hélicoïdales : ceci est pris en compte dans la modélisation des paliers via un changement de variable dans l'équation de Reynolds. Concernant la butée hydrodynamique à patins oscillants, l'équation de Reynolds est explicitée en fonction des paramètres du système (rotor et patins). Un cas test est également présenté afin d'évaluer les différentes approches possibles pour l'intégration dans la modélisation du rotor et pour mieux appréhender la réponse dynamique d'une butée. Les joints d'étanchéités sont modélisés en linéarisant les efforts hydrauliques gouvernés par les équations du "bulk-flow" et sont donc représentés par des coefficients dynamiques de masse, d'amortissement et de raideur. Les efforts électromagnétiques au niveau de l'alternateur sont pris en compte via une formulation analytique des forces d'attraction sur chaque paire de pôles. Cela permet de gérer, par exemple, des défauts d'ovalisation ou de positionnement du stator.Une seconde partie est consacrée à l'étude d'une turbine complète. Y sont présentées différentes études de sensibilités des défauts les plus courants sur ce type de machine, le but étant d'en connaître l'influence sur le comportement dynamique de l'ensemble du rotor. / Vibration problems are one of the main causes leading to maintenances performed on the turbines of hydroelectric power generation systems in France. In this CIFRE dissertation, financed by Division Technique Générale d'Électricité de France in Grenoble, we shall numerically study the physical phenomena involved in turbine vibrations of this kind.Hence, each component of this type of rotating machinery is modeled: the rotor, the rigid coupling, the hydrodynamic bearings, the hydrodynamic tilting pad thrust bearing, the annular seals and the electromagnetic forces. The model of the rotor is based on classical 1D approach taking into account the defects of the rigid coupling. The hydrodynamic bearings can be fed by helicoidally grooves. This feature is taken into account in the numerical model of journal bearing by applying a variable transformation to the Reynolds equation. For the tilting pad thrust bearing, the Reynolds equation takes into account the displacements and the velocities of both the pads and the rotor. A test case is presented for evaluating the different numerical approaches of the tilting pad thrust bearing that can be integrated in a rotordynamic analysis. The annular seals are modeled by using linearized hydraulic efforts (i.e. stiffness, damping and added mass dynamic coefficients) modeled by the "bulk flow" system of equations. The electromagnetic efforts in the alternator are taken into account by using an analytic model of the forces of each pair of poles. This enables to tackle ovalisation or eccentricity defects of the stator.A second part is dedicated to the numerical study of a complete turbine. Different studies dealing with sensitivity analyses of most often-encountered defects of this type of rotating machinery are presented, the goal being to underline their influence on the dynamic behavior of the whole rotor.
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Polyfunkční dům / Multi-purpose building

Paksi, Richard January 2019 (has links)
The diploma thesis deals with the design and elaboration process of project documentation of newly-built multi-purpose building in Sturovo. The building is designed as a three-storey building with a partial fourth storey. A footprint of the building is created by the irregular shape of the letter „L“ with an angle of 110 °. The building is roofed with a warm flat roof. The roof above the third storey is designed as a walkable flat roof divided in a green roof part and part with concrete paving. Spatial zoning of the building consists of three main spaces. There is a bookstore zone and coffee shop situated on the ground floor. The second and third floor is designed for administrative spaces. Premises of the second floor are designed as an activity-based office with open spaces. Third floor focus on closed offices. The meeting rooms, chill-out zones, break rooms with kitchenettes are available in both of them. Technical facilities and utility rooms are situated also on the ground floor. There is a room with kitchenette, storage rooms and utility rooms in the fourth ground. Public zones of building and administrative zones are accessible. The structural system of a building is designed as a cast-in-place reinforced concrete frame in a combination with a shear core. Ceilings consist of cast-in-place beam-supported reinforced concrete one-way slab. The structure is based on foundation pads and strip foundations. infill wall is made of vertically perforated blocks. Exterior walls and insulated with ventilated facades system.

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