Literatura científica selecionada sobre o tema "Finites differences"

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Artigos de revistas sobre o assunto "Finites differences"

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Mendonça, Agostinho, e M. Lurdes Lopes. "Pre-Tensioned Geogrids Reinforced Soil Structures with Face Panels in Fiber Glass". Materials Science Forum 587-588 (junho de 2008): 857–61. http://dx.doi.org/10.4028/www.scientific.net/msf.587-588.857.

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This paper presents an innovative technology for soil reinforced structures. The technology is based on the use of pre-tensioned geogrids reinforcements and face panels reinforced with fiber glass. Main technology advantages are: i) the very light face with great variety of geometries, size, color and surface textures; ii) either the face and the reinforcements are corrosion free; iii) the good behavior under seismic actions; iv) reduction of structure horizontal strains due to the pre-tension. First, the state of art on reinforced soil structures is done and then the constituents of the new technology are presented followed by the reference to the main theoretical principles considered in its conception. Secondly, numerical data from the behavior, in static conditions, of geogrid reinforced soil structures with and without pre-tensioned reinforcements are presented. In the numerical study the FLAC program, based on the differences finites method, will be used. The construction of the structures will be modeled considering the sequential placement of soil layers and reinforcements, enhancing the deformation behavior of the structures. Thirdly, the advantages of the new technology against the traditional ones are quantified, based on the results of the numerical studies. Special relevance will be given to face horizontal deformations and reinforcements strains. Finally, the main conclusions about the new technology will be put forward and its main advantages towards traditional technologies will be listed. Application fields where the technology is competitiveness will be identified.
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Lugo Jiménez, Abdul Abner, Guelvis Enrique Mata Díaz e Bladismir Ruiz. "A comparative analysis of methods: mimetics, finite differences and finite elements for 1-dimensional stationary problems". Selecciones Matemáticas 8, n.º 1 (30 de junho de 2021): 1–11. http://dx.doi.org/10.17268/sel.mat.2021.01.01.

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Numerical methods are useful for solving differential equations that model physical problems, for example, heat transfer, fluid dynamics, wave propagation, among others; especially when these cannot be solved by means of exact analysis techniques, since such problems present complex geometries, boundary or initial conditions, or involve non-linear differential equations. Currently, the number of problems that are modeled with partial differential equations are diverse and these must be addressed numerically, so that the results obtained are more in line with reality. In this work, a comparison of the classical numerical methods such as: the finite difference method (FDM) and the finite element method (FEM), with a modern technique of discretization called the mimetic method (MIM), or mimetic finite difference method or compatible method, is approached. With this comparison we try to conclude about the efficiency, order of convergence of these methods. Our analysis is based on a model problem with a one-dimensional boundary value, that is, we will study convection-diffusion equations in a stationary regime, with different variations in the gradient, diffusive coefficient and convective velocity.
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Jones, Michael A. "A Difference Equation Approach to Finite Differences of Polynomials". College Mathematics Journal 51, n.º 5 (12 de novembro de 2020): 375–77. http://dx.doi.org/10.1080/07468342.2020.1760065.

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Kazhikenova, S. Sh. "FINITE DIFFERENCE METHOD IMPLEMENTATION FOR NUMERICALINTEGRATION HYDRODYNAMIC EQUATIONS MELTS". Eurasian Physical Technical Journal 17, n.º 1 (junho de 2020): 145–50. http://dx.doi.org/10.31489/2020no1/145-150.

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Carpenter, Mark H., e John Otto. "High-Order "Cyclo-Difference" Techniques: An Alternative to Finite Differences". Journal of Computational Physics 118, n.º 2 (maio de 1995): 242–60. http://dx.doi.org/10.1006/jcph.1995.1096.

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S, Aiswarya, e Gerly T G. "Finite Series Solution Arising from Three-Dimensional q-Difference Equation". Journal of Computational Mathematica 2, n.º 2 (30 de dezembro de 2018): 41–50. http://dx.doi.org/10.26524/cm38.

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Ochilov, Sherali Baratovich, Gulrukh Djumanazarovna Khasanova e Oisha Kurbanovna Khudayberdieva. "Method For Constructing Correlation Dependences For Functions Of Many Variables Used Finite Differences". American Journal of Management and Economics Innovations 03, n.º 05 (31 de maio de 2021): 46–52. http://dx.doi.org/10.37547/tajmei/volume03issue05-08.

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The article considers a method for constructing correlation models for finite-type functions using a set of variables. The use of the method of unknown squares in the construction of correlation models and the construction of higher-quality models is also justified. The proposed correlation models are considered on the example of statistical data of the Bukhara region of the Republic of Uzbekistan.
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Kratz, Werner. "An inequality for finite differences via asymptotics of Riccati matrix difference equations". Journal of Difference Equations and Applications 4, n.º 3 (janeiro de 1998): 229–46. http://dx.doi.org/10.1080/10236199808808140.

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Kawada, Naoki, Takeshi Yoda, Norio Tagawa, Takao Tsuchiya e Kan Okubo. "Evaluation of Acoustic Simulation Using Wave Equation Finite Difference Time Domain Method with Compact Finite Differences". Japanese Journal of Applied Physics 51, n.º 7S (1 de julho de 2012): 07GG06. http://dx.doi.org/10.7567/jjap.51.07gg06.

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Kawada, Naoki, Takeshi Yoda, Norio Tagawa, Takao Tsuchiya e Kan Okubo. "Evaluation of Acoustic Simulation Using Wave Equation Finite Difference Time Domain Method with Compact Finite Differences". Japanese Journal of Applied Physics 51 (20 de julho de 2012): 07GG06. http://dx.doi.org/10.1143/jjap.51.07gg06.

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Teses / dissertações sobre o assunto "Finites differences"

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Floyd, Stewart Allen. "A qualitative analysis of finite difference equations in R[superscript n]". Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/29441.

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Ampadu, Ebenezer. "Implementation of some finite difference methods for the pricing of derivatives using C++ programming". Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/.

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Kama, Phumezile. "Non-standard finite difference methods in dynamical systems". Thesis, Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-07132009-163422.

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Chirvasa, Mihaela. "Finite difference methods for 1st Order in time, 2nd order in space, hyperbolic systems used in numerical relativity". Phd thesis, Universität Potsdam, 2010. http://opus.kobv.de/ubp/volltexte/2010/4213/.

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This thesis is concerned with the development of numerical methods using finite difference techniques for the discretization of initial value problems (IVPs) and initial boundary value problems (IBVPs) of certain hyperbolic systems which are first order in time and second order in space. This type of system appears in some formulations of Einstein equations, such as ADM, BSSN, NOR, and the generalized harmonic formulation. For IVP, the stability method proposed in [14] is extended from second and fourth order centered schemes, to 2n-order accuracy, including also the case when some first order derivatives are approximated with off-centered finite difference operators (FDO) and dissipation is added to the right-hand sides of the equations. For the model problem of the wave equation, special attention is paid to the analysis of Courant limits and numerical speeds. Although off-centered FDOs have larger truncation errors than centered FDOs, it is shown that in certain situations, off-centering by just one point can be beneficial for the overall accuracy of the numerical scheme. The wave equation is also analyzed in respect to its initial boundary value problem. All three types of boundaries - outflow, inflow and completely inflow that can appear in this case, are investigated. Using the ghost-point method, 2n-accurate (n = 1, 4) numerical prescriptions are prescribed for each type of boundary. The inflow boundary is also approached using the SAT-SBP method. In the end of the thesis, a 1-D variant of BSSN formulation is derived and some of its IBVPs are considered. The boundary procedures, based on the ghost-point method, are intended to preserve the interior 2n-accuracy. Numerical tests show that this is the case if sufficient dissipation is added to the rhs of the equations.
Diese Doktorarbeit beschäftigt sich mit der Entwicklung numerischer Verfahren für die Diskretisierung des Anfangswertproblems und des Anfangs-Randwertproblems unter Einsatz von finite-Differenzen-Techniken für bestimmte hyperbolischer Systeme erster Ordnung in der Zeit und zweiter Ordnung im Raum. Diese Art von Systemen erscheinen in einigen Formulierungen der Einstein'schen-Feldgleichungen, wie zB. den ADM, BSSN oder NOR Formulierungen, oder der sogenanten verallgemeinerten harmonischen Darstellung. Im Hinblick auf das Anfangswertproblem untersuche ich zunächst tiefgehend die mathematischen Eigenschaften von finite-Differenzen-Operatoren (FDO) erster und zweiter Ordnung mit 2n-facher Genaugigkeit. Anschließend erweitere ich eine in der Literatur beschriebene Methode zur Stabilitätsanalyse für Systeme mit zentrierten FDOs in zweiter und vierter Genauigkeitsordung auf Systeme mit gemischten zentrierten und nicht zentrierten Ableitungsoperatoren 2n-facher Genauigkeit, eingeschlossen zusätzlicher Dämpfungsterme, wie sie bei numerischen Simulationen der allgemeinen Relativitätstheorie üblich sind. Bei der Untersuchung der einfachen Wellengleichung als Fallbeispiel wird besonderes Augenmerk auf die Analyse der Courant-Grenzen und numerischen Geschwindigkeiten gelegt. Obwohl unzentrierte, diskrete Ableitungsoperatoren größere Diskretisierungs-Fehler besitzen als zentrierte Ableitungsoperatoren, wird gezeigt, daß man in bestimmten Situationen eine Dezentrierung des numerischen Moleküls von nur einem Punkt bezüglich des zentrierten FDO eine höhere Genauigkeit des numerischen Systems erzielen kann. Die Wellen-Gleichung in einer Dimension wurde ebenfalls im Hinblick auf das Anfangswertproblem untersucht. In Abhängigkeit des Wertes des sogenannten Shift-Vektors, müssen entweder zwei (vollständig eingehende Welle), eine (eingehende Welle) oder keine Randbedingung (ausgehende Welle) definiert werden. In dieser Arbeit wurden alle drei Fälle mit Hilfe der 'Ghost-point-methode' numerisch simuliert und untersucht, und zwar auf eine Weise, daß alle diese Algorithmen stabil sind und eine 2n-Genauigkeit besitzen. In der 'ghost-point-methode' werden die Evolutionsgleichungen bis zum letzen Punkt im Gitter diskretisiert unter Verwendung von zentrierten FDOs und die zusätzlichen Punkte die am Rand benötigt werden ('Ghost-points') werden unter Benutzung von Randwertbedingungen und Extrapolationen abgeschätzt. Für den Zufluß-Randwert wurde zusätzlich noch eine andere Implementierung entwickelt, welche auf der sogenannten SBP-SAT (Summation by parts-simulatanous approximation term) basiert. In dieser Methode werden die diskreten Ableitungen durch Operatoren angenähert, welche die 'Summation-by-parts' Regeln erfüllen. Die Randwertbedingungen selber werden in zusätzlichen Termen integriert, welche zu den Evolutionsgleichnungen der Punkte nahe des Randes hinzuaddiert werden und zwar auf eine Weise, daß die 'summation-by-parts' Eigenschaften erhalten bleiben. Am Ende dieser Arbeit wurde noch eine eindimensionale (kugelsymmetrische) Version der BSSN Formulierung abgeleitet und einige physikalisch relevanten Anfangs-Randwertprobleme werden diskutiert. Die Randwert-Algorithmen, welche für diesen Fall ausgearbeitet wurden, basieren auf der 'Ghost-point-Methode' and erfüllen die innere 2n-Genauigkeit solange genügend Reibung in den Gleichungen zugefügt wird.
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FANTI, ALESSANDRO. "A generalized finite difference approach to the computation of modes". Doctoral thesis, Università degli Studi di Cagliari, 2012. http://hdl.handle.net/11584/266145.

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This thesis deals with numerical techniques for the computation of modes in electromagnetic structures with arbitrary geometry. The approach proposed in this work is based on the Finite Difference (FD) and Vector Finite Difference (VFD), which are applied to rectangular, circular, elliptical geometries, and to combination of them. The FD is applied using a 2D cartesian, polar and elliptical grid in the waveguide section. A suitable Taylor expansion of the mode function allows, either for scalar and for vector FD, to take exactly into account the boundary condition. To prevent the raising of spurious modes, the VFD approximation results in a constrained eigenvalue problem, that has been solved using a decomposition method. All approaches presented have been validated comparing the results to the analytical modes of rectangular and circular waveguide, and to known data for the elliptic case. The standard calculation of the waveguide modes using FD requires the use of two different grids, namely one for TE modes and the other for TM modes, due to the different boundary condition. It has been shown that a single grid can be used for all modes, thus allowing an effective mode-matching solution. The FD approach has been extended to waveguides (and apertures) with irregular boundaries, and therefore non-regular discretization grids. It has been shown that a suitable FD approximation of the Laplace operator is still possible. A ridged-waveguide, with trapezoidal ridges, and a rounded-ended waveguide have been considered in detail.
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Munerato, Fernando Perin. "Remigração na profundidade mediante a equação da onda imagem". [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307301.

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Orientadores: Joerg Schleicher, Amelia Novais
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: Este trabalho aborda a questão de como resolver a equação da onda imagem para o problema de remigração na profundidade através de métodos numéricos. O objetivo deste problema é a reconstrução de uma imagem das camadas geológicas do subsolo a partir de uma imagem previamente migrada com um modelo de velocidade, geralmente, incorreto. Nosso principal objetivo neste trabalho é a investigação de possíveis métodos que possam resolver os problemas que surgiram ao usarmos esquemas explícitos do método de diferenças _nitas na solução da equação da onda imagem em trabalhos anteriores, como, por exemplo, a dispersão numérica. Para isso, estudamos aqui o método de volumes _nitos, assim como esquemas implícitos do método de diferenças _nitas. O método de volumes _nitos possui como característica principal propagar as médias das células da malha ao invés de simplesmente os dados pontuais como é feito no método de diferenças _nitas. As outras tentativas para solucionar o problema da dispersão foram dois tipos de implementação de esquemas implícitos do método de diferenças _nitas, isto é, implementações implícitas de esquemas convencionais avaliados em pontos da malha e um esquema avaliado nos centros das células. A qualidade dos algoritmos estudados foi testada numericamente. Estes testes numéricos mostram que o método de volumes _nitos não é adequado para resolver o problema da dispersão, uma vez que a média calculada a cada passo aumenta o estiramento do pulso. Além disso, as implementações implícitas dos esquemas convencionais mostram o mesmo comportamento de dispersão que as implementações explícitas. Unicamente o esquema centrado foi capaz de melhorar a dispersão numérica em comparação com as implementações anteriores,porém somente para dados contendo exclusivamente baixas freqüências
Abstract: This work approaches the question of how to solve the image-wave equation for depth remigration by numerical methods. The objective is the reconstruction of an image of the geologic layers of the subsoil from a previously migrated image with a different velocity model. Our main objective in this work is the investigation of possible methods that can solve the problems that appeared when using explicit _nite-difference schemes for the solution of the image-wave equation in previous works, particularly numerical dispersion. For this purpose, we study the method of _nite volumes, as well as implicit _nite-difference schemes. The main characteristic of the _nite-volume method is to simply propagate the averages in the cells of the mesh instead of the discretized data themselves as it is done in the _nitedifference method. As another attempt to solve the problem of the dispersion, we study two types of implementation of implicit _nite-difference schemes, that is, implicit implementations of conventional schemes evaluated out the edge of the cell and a scheme evaluated in the center of the cell. The quality of the studied algoritms has been tested numerically. These numerical tests show that the method of _nite volumes is not adequate to solve the problem of dispersion, for the average calculated in each step additionally increases the pulse stretch. Moreover, the implicit implementations of the conventional schemes show the same dispersion behavior as the explicit implementations. Solely the centered scheme was capable to improve the numerical dispersion in comparison with the previous implementations, however only for data containing
Mestrado
Geofisica Computacional
Mestre em Matemática Aplicada
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Teramoto, Elias Hideo [UNESP]. "Caracterização hidrogeológica e simulação numérica de fluxo em uma região situada no distrito industrial de Paulínia (SP)". Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/92749.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Em área contaminada por hidrocarbonetos, situada no município de Paulínia, a migração dos contaminantes e a eficiência do sistema de bombeamento são governadas pela heterogeneidade litológica do aqüífero local, constituído por rochas do Subgrupo Itararé, rochas intrusivas básicas da Formação Serra Geral e por sedimentos cenozóicos correlatos à Formação Rio Claro. Desta forma, o entendimento da heterogeneidade que caracteriza este aqüífero e suas propriedades hidráulicas é essencial para a otimização e o aprimoramento do processo de remediação. Visando delinear o entendimento e a caracterização hidrogeológica local, foi elaborado modelo hidrogeológico conceitual, por meio da integração de dados provenientes de técnicas tradicionais de investigação, tais como métodos geofísicos, monitoramento dos níveis piezométricos de poços de monitoramento, descrições geológicas e análises granulométricas, para entendimento da dinâmica de fluxo local, distribuição litológica do substrato aqüífero e seus valores de condutividade hidráulica. Foram ainda realizadas simulações numéricas de fluxo em regime permanente, utilizando o software Visual Modflow, que emprega o método de diferenças finitas para testar o modelo conceitual concebido. A simulação numérica apresentou excelentes correlações entre os valores de cargas hidráulicas medidas e simuladas e os resultados obtidos permitiram verificar a consistência do modelo conceitual.
In an hydrocarbon contaminated area locate in Paulínia city, lithological heterogeneity of local aquifer controls the migration of contaminant and the efficiency of pump system. The aquifer is composed by sedimentary rocks of Itararé Sub-group, basic intrusive of Serra Geral Formation and cenozoic sediments correlated to Rio Claro Formation. Therefore, understanding heterogeinity that characterize the aquifer and its hydraulic properties is vital to optimization and improvement of remediation process. For hydrogeological characterization of the local aquifer, a conceptual hydrogeological model was elaborated by integrating traditional investigations tools, such as geophysical methods, piezometric level monitoring, and geological descriptions in drillings and granulometric analysis to understanding of local dynamic flow, lithological distributions and hydraulic conductivity. Numerical simulation under steady-state condition using Visual Modflow, which utilizes the finite differences method were performed to test the conceived conceptual model. The measured and calculated hydraulic heads are in excellent agreement, showing the consistency of the conceptual model.
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Sousa, Nadson de. "Metodos de diferenças finitas : conceitos e interpretações". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/306426.

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Orientador: Ricardo Caetano Azevedo Biloti
Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: O presente trabalho aborda os métodos de diferenças finitas com suas propriedades e aplicações. Iniciamos com uma revisão histórica, destacando alguns matemáticos que participaram do desenvolvimento da teoria de métodos de diferenças. Em seguida, apresentamos alguns modelos matemáticos compostos por equações diferenciais. Através da equação de advecção, estudamos métodos de diferenças explícitos, com especial enfoque para as propriedades de erro de truncamento, consistência, estabilidade e convergência dando ênfase ao Teorema de Lax. Estudamos a análise de Fourier e a condição de von Neumann para interpretar a amplitude, a dissipação e a dispersão das soluções numéricas. Abordamos os métodos Upwind, de Lax-Friedrichs e de Lax-Wendroff. Por fim, exemplificamos numericamente os conceitos e propriedades estudados com comparações entre os métodos, aplicados em um problema teste.
Abstract: The present work approaches finite-difference methods, their properties, and their applications. We present a historical review, including some mathematieians who participated in the development of the theory of differences. Furthermore, we present some mathematical models consisting of differential equatiolls. Through the advection equationl, we study explicit finite-difference methods, detailing their truncation error, consistency, stability and conlvergence properties. We employ Fourier analysis and the von Neumann condition to study the amplitude, dissipation and dispersion of numerical solutions. We compare three methods: Upwind, Lax-Friedrichs and Lax-Wendroff. Finally, we perform numerical tests to illustrate the concepts and properties studied in this work.
Mestrado
Analise Numerica
Mestre em Matemática
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Alves, Diogo Stuani. "Investigação do efeito térmico no comportamento dinâmico de mancais hidrodinâmicos". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264183.

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Orientador: Kátia Lucchesi Cavalca Dedini
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Os mancais lubrificados hidrodinamicamente estão presentes em muitas aplicações modernas, especialmente em maquinas rotativas que necessitam de operações mais precisas. Nestes casos, a lubrificação é essencial para a máquina, pois, diminui o atrito entre as peças internas e previne o contato metal-metal, além de agir como elemento de vinculo dinâmico para as pistas do mancal. Devido ao cisalhamento do lubrificante durante a operação, tem-se o aquecimento do fluido e com isso uma modificação nas condições de lubrificação, já que a viscosidade, parâmetro que caracteriza as particularidades do escoamento, diminui com o aumento da temperatura. A diminuição da viscosidade causa diminuição do atrito viscoso, o que acarreta em diminuição da capacidade de carga, gerando efeitos negativos nos coeficientes equivalentes e sendo possível, em alguns casos, a observação de contato direto entre as partes metálicas. Sendo assim, o estudo do atrito e das condições de lubrificação durante a operação de máquinas é de extrema importância em problemas como manutenção, durabilidade e confiabilidade de máquinas. Utilizando o método das diferenças finitas, é possível resolver simultaneamente as equações de Reynolds e da energia, que são responsáveis pelas distribuições de pressão e temperatura, respectivamente. Com isso, é possível analisar as diferenças de pressão, disposição do eixo no interior do mancal e coeficientes equivalentes de rigidez e amortecimento, de um modelo em que se usa viscosidade variante com a temperatura (termohidrodinâmico) e de um modelo que não apresenta esse fenômeno (isotérmico). Finalmente, utilizando um software de dinâmica de rotores, foi obtida a resposta dinâmica de um sistema mancal-rotor para turbocompressores
Abstract: The hydrodynamic lubricated bearings are present in modern applications, especially in rotational machines that need precisely operations. In those cases, the lubrication is essential for the machine, because it reduces the wear between the internal parts and prevents the metallic contact, and also, acts like an element of dynamic link for the bearing. Due to the lubricant shear, the fluid heats up and modifications on the lubrication conditions occurs, since the viscosity, parameter that characterize the flow, decreases with the increase of the temperature. The decrease of visco ity causes a decrease in the viscous friction, which entails in a decrease of the load sustaining capacity, negative effects in the equivalent coefficients and possible observation of metallic contact. So, the study of friction and lubrication conditions during the machine operation is extremely important on maintenance, durability and reliability of machines. Using the finite difference method it is possible to solve, simultaneously, the Reynolds and the energy equations that are responsible for the pressure and temperature distribution, respectively. Therewith, it is possible to analyze the differences in pressure, shaft position in the bearing and equivalent stiffness and damping coefficients, for a model that uses changes in viscosity with the temperature (thermohydrodynamic) and for a model that does not take it in account (isothermal). Finally, using a rotordynamic software (ROTORTEST), the dynamic response of a turbocharger bearing-rotor system was obtained and analyzed
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica
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Campos, Marco Donisete de 1976. "Aplicações do método das diferenças finitas de alta ordem na solução de problemas de convecção-difusão : Applications of high-order finite difference method in the solution of the convection-diffusion equation". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265963.

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Orientador: Luiz Felipe Mendes de Moura
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: O presente trabalho tem como objetivo aplicar o método de diferenças finitas de alta ordem na solução de problemas bi e tridimensionais convectivo-difusivos transientes. As simulações numéricas foram realizadas para investigar, nos problemas lineares, o termo de dissipação viscosa na equação de transferência de calor bidimensional com ênfase, no caso tridimensional, na aplicação envolvendo troca de calor num canal retangular. Para problemas não lineares, o método de Newton para a linearização do termo convectivo foi usado para resolver a equação de Burgers bi e tridimensionais. O esquema desenvolvido mostrou-se simples, computacionalmente rápido, podendo ser aplicado para problemas bi e tridimensionais. Nas aplicações propostas, quando possível, as soluções analíticas disponíveis na revisão da literatura foram utilizadas para comparações com as soluções numéricas e validação do código, sendo a análise dos resultados feita a partir das normas L2 e L?
Abstract: The present study aims to apply the high-order Finite Difference Method to transient diffusive-convective problems in two and three dimensions. Numerical simulations have been undertaken to investigate, in the linear problems, the viscous dissipation term in the two-dimensional heat transfer equation with emphasis, in the three-dimensional case, on the application involving heat exchange in a rectangular channel. For nonlinear problems, the Newton's method for the linearization of the convective term was used for solving the two and three dimensional Burgers equation. This scheme is simple, computationally fast and can be applied for two or three-dimensional problems. For the proposed applications, whenever possible, the analytical solutions found in the literature review were used to compare with the numerical solutions. The analysis of results was done from the L2 and L? norms
Doutorado
Termica e Fluidos
Doutor em Engenharia Mecânica
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Livros sobre o assunto "Finites differences"

1

Milne-Thomson, L. M. The calculus of finite differences. Providence, R.I: AMS Chelsea Pub., 2000.

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2

Harmuth, Henning F. Dirac's difference equation and the physics of finite differences. Amsterdam: Academic Press, 2008.

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3

1774-1844, Otto John C., e Langley Research Center, eds. High-order "cyclo-difference" techniques: An alternative to finite differences. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1993.

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4

F, Lessman, ed. Finite difference equations. New York: Dover Publications, 1992.

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5

Levy, Hyman. Finite difference equations. New York: Dover Pubns., 1992.

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6

United States. National Aeronautics and Space Administration., ed. Accurate finite difference algorithms. [Washington, D.C: National Aeronautics and Space Administration, 1996.

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7

Reece, Gordon. Microcomputer Modelling by Finite Differences. London: Macmillan Education UK, 1986. http://dx.doi.org/10.1007/978-1-349-09051-8.

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8

Li, Qian. Generalized difference method. Taejon, Korea: Korea Advanced Institute of Science and Technology, Mathematics Research Center, 1997.

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9

Shlomo, Ta'san, e Langley Research Center, eds. Finite difference schemes for long-time integration. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1993.

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10

David, Gottlieb, Abarbanel Saul S. 1931- e Langley Research Center, eds. Time-stable boundary conditions for finite-difference schemessolving hyperbolic systems: Methodology and application to high-order compact schemes. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1993.

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Capítulos de livros sobre o assunto "Finites differences"

1

Vesely, Franz J. "Finite Differences". In Computational Physics, 7–22. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4757-2307-6_1.

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Vesely, Franz J. "Finite Differences". In Computational Physics, 7–20. Boston, MA: Springer US, 2001. http://dx.doi.org/10.1007/978-1-4615-1329-2_1.

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3

Crépey, Stéphane. "Finite Differences". In Springer Finance, 213–41. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37113-4_8.

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4

Orlandi, Paolo. "Finite differences". In Fluid Mechanics and Its Applications, 8–39. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4281-6_3.

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5

Maubourguet, Marie-Madeleine, e Jean-Michel Tanguy. "Finite Differences". In Numerical Methods, 95–107. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118557877.ch6.

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6

Olver, Peter J. "Finite Differences". In Introduction to Partial Differential Equations, 181–214. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-02099-0_5.

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7

Puzrin, Alexander M. "Finite Differences". In Constitutive Modelling in Geomechanics, 83–100. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-27395-7_7.

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Franciss, Fernando Olavo. "Finite differences". In Hard Rock Hydraulics, 182–242. Boca Raton : CRC Press, [2021]: CRC Press, 2021. http://dx.doi.org/10.1201/9780429355325-5.

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Rylander, Thomas, Pär Ingelström e Anders Bondeson. "Finite Differences". In Computational Electromagnetics, 19–42. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-5351-2_3.

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10

Euler. "On Finite Differences". In Foundations of Differential Calculus, 1–24. New York, NY: Springer New York, 2000. http://dx.doi.org/10.1007/0-387-22645-1_1.

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Trabalhos de conferências sobre o assunto "Finites differences"

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Bonasera, Aldo, e Jurgen Schulte. "Scaling of large fluctuations in finite systems". In Similarities and differences between atomic nuclei and clusters. AIP, 1997. http://dx.doi.org/10.1063/1.54566.

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2

Popenda, Jerzy. "Finite Difference Equations and Periodicity". In Proceedings of the Third International Conference on Difference Equations. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742: CRC Press, 2017. http://dx.doi.org/10.4324/9780203745854-25.

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Song, X., e S. Fomel. "Lowrank Finite-differences and Lowrank Fourier Finite-differences for Seismic Wave Extrapolation". In 74th EAGE Conference and Exhibition incorporating EUROPEC 2012. Netherlands: EAGE Publications BV, 2012. http://dx.doi.org/10.3997/2214-4609.20148577.

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Novais, A., J. Costa e R. Portuga. "Velocity continuation by finite differences". In 9th International Congress of the Brazilian Geophysical Society & EXPOGEF, Salvador, Bahia, Brazil, 11-14 September 2005. Society of Exploration Geophysicists and Brazilian Geophysical Society, 2005. http://dx.doi.org/10.1190/sbgf2005-301.

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Novais, A., e J. Costa and R. Portugal. "Velocity continuation by finite differences". In 9th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 2005. http://dx.doi.org/10.3997/2214-4609-pdb.160.sbgf302.

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Cunha, Carlos, Gerson Ritter, Fernanda Thedy, Alexandre Sardinha e Nelson Hargreaves. "Finite-Difference Kirchhoff Migration". In International Congress of the Brazilian Geophysical Society&Expogef. Brazilian Geophysical Society, 2019. http://dx.doi.org/10.22564/16cisbgf2019.307.

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Levin, Stewart A. "Parallel finite-difference migration". In SPIE's 1993 International Symposium on Optics, Imaging, and Instrumentation, editado por Sergio E. Zarantonello. SPIE, 1993. http://dx.doi.org/10.1117/12.164839.

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Dellinger, Joe. "Anisotropic finite‐difference traveltimes". In SEG Technical Program Expanded Abstracts 1991. Society of Exploration Geophysicists, 1991. http://dx.doi.org/10.1190/1.1888998.

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Levin, Stewart A. "Parallel finite‐difference migration". In SEG Technical Program Expanded Abstracts 1986. Society of Exploration Geophysicists, 1986. http://dx.doi.org/10.1190/1.1893052.

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Blanch, J. O., J. O. A. Robertsson e W. W. Symes. "Viscoelastic finite‐difference modeling". In SEG Technical Program Expanded Abstracts 1993. Society of Exploration Geophysicists, 1993. http://dx.doi.org/10.1190/1.1822675.

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Relatórios de organizações sobre o assunto "Finites differences"

1

Manzini, Gianmarco. The Mimetic Finite Difference Method. Office of Scientific and Technical Information (OSTI), maio de 2013. http://dx.doi.org/10.2172/1078363.

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2

Bohn, Robert B., e Edward J. Garboczi. User manual for finite element and finite difference programs:. Gaithersburg, MD: National Institute of Standards and Technology, 2003. http://dx.doi.org/10.6028/nist.ir.6997.

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Li, Jianchao. Finite-difference migration to zero offset. Office of Scientific and Technical Information (OSTI), julho de 1992. http://dx.doi.org/10.2172/10159178.

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Li, Jianchao. Finite-difference migration to zero offset. Office of Scientific and Technical Information (OSTI), janeiro de 1992. http://dx.doi.org/10.2172/7068849.

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Kain, K. E. Finite-difference program for hydrogen diffusion. Office of Scientific and Technical Information (OSTI), março de 1987. http://dx.doi.org/10.2172/6546416.

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Preston, Leiph. Optimized Finite-Difference Coefficients for Acoustic Modeling. Office of Scientific and Technical Information (OSTI), outubro de 2016. http://dx.doi.org/10.2172/1431192.

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Moran, Mark, Steve Ketcham e Roy Greenfield. Three Dimensional Finite-Difference Seismic Signal Propagation. Fort Belvoir, VA: Defense Technical Information Center, agosto de 1999. http://dx.doi.org/10.21236/ada393626.

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Dey, T. N. An effective model for dynamic finite difference calculations. Office of Scientific and Technical Information (OSTI), janeiro de 1996. http://dx.doi.org/10.2172/204199.

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Mughabghab, S., A. Azarm e D. Stock. Macroscopic traffic modeling with the finite difference method. Office of Scientific and Technical Information (OSTI), março de 1996. http://dx.doi.org/10.2172/226027.

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10

Stephen, Ralph A. Seafloor Scattering in Three Dimensions by Time Domain Finite Differences. Fort Belvoir, VA: Defense Technical Information Center, fevereiro de 2006. http://dx.doi.org/10.21236/ada443945.

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