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‣ Multiphase flow in the vascular system of wood: From microscopic exploration to 3-D Lattice Boltzmann experiments

FRANK, X.; ALMEIDA, G.; PERRE, P.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
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This paper provides insights into liquid free water dynamics in wood vessels based on Lattice Boltzmann experiments. The anatomy of real wood samples was reconstructed from systematic 3-D analyses of the vessel contours derived from successive microscopic images. This virtual vascular system was then used to supply fluid-solid boundary conditions to a two-phase Lattice Boltzmann scheme and investigate capillary invasion of this hydrophilic porous medium. Behavior of the liquid phase was strongly dependent on anatomical features, especially vessel bifurcations and reconnections. Various parameters were examined in numerical experiments with ideal vessel bifurcations, to clarify our interpretation of these features. (c) 2010 Elsevier Ltd. All rights reserved.; CPER; (Conseil General des Vosges); regional (Region Lorraine); national (DRRT and FNADT); European (FEDER)

‣ Desenvolvimento de um simulador computacional de dinâmica de fluidos utilizando o método de Lattice Boltzmann.; Development of a computational simulator fo fluid dynamica using the Lattice Boltzmann method.

Komori, Fabio Sussumu
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/05/2012 Português
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Este trabalho aborda a utilização do método de Lattice Boltzmann como ferramenta de simulação para a área de dinâmica de fluidos. Além disso, apresenta o programa LBSim desenvolvido durante o período de pesquisa, construído para ser flexível e extensível (através do emprego de técnicas de orientação a objetos) e com uma interface gráfica mais amigável do que outros projetos semelhantes. Como resultado deste trabalho, o software LBSim implementa uma série de módulos diferentes que utilizam o método de Lattice Boltzmann como base, permitindo a simulação de casos monofásico, multifásico, multicomponente, com suporte à gravidade, meios porosos, difusão, transferência de calor e paredes deslizantes.; This work approaches the use of the Lattice Boltzmann method as a simulation tool for the fluid dynamics area. Beyond that, it presents the LBSim software, developed during the period of the research and built to be flexible and extensible (through the application of techniques of the object oriented paradigm) and with a graphical interface more friendly than other similar projects. As a result of this work, the LBSim software implements a series of different modules that uses the Lattice Boltzmann method as a base...

‣ Extração de diterpenos de café verde: modelagem fenomenológica e caracterização de parâmetros via método lattice Boltzmann; Diterpene extraction of green coffee beans: phenomenological modeling and characterization of parameters by lattice Boltzmann method

Rosa, Robson Humberto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/09/2014 Português
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Por meio do método lattice Boltzmann (LBM), este projeto de pesquisa propõe a simulação computacional da extração dos compostos diterpênicos do café verde em sistemas com fluido pressurizado. Para isso foi adotado um modelo fenomenológico dinâmico e de primeira ordem quanto à dependência espacial. Usando a rede D1Q2, o LBM foi implementado com duas funções de distribuição de partículas, acompanhadas das respectivas funções de distribuição de equilíbrio. Cada função refere-se à concentração em uma dada fase (sólida e fluida). A previsão das curvas de rendimento pressupõe o conhecimento dos parâmetros do processo, tais como a difusividade mássica interna (intrapartícula), o coeficiente de partição volumétrica e a difusividade mássica axial. Para o devido ajuste destes parâmetros contra dados experimentais, foi desenvolvido um código computacional utilizando a técnica de gradiente descendente. Resultados numéricos das simulações foram comparados com dados experimentais e mostraram-se satisfatórios. Adicionalmente, foi realizada a análise da influência dos parâmetros supracitados mediante a criação de uma interface gráfica amigável para o código computacional original. Este projeto de pesquisa...

‣ Distribuição de dados para implementações paralelas do Método de Lattice Boltzmann; Data distribution for parallel implementations of the Lattice Boltzmann Method

Schepke, Claudio
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
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A Dinâmica de Fluidos Computacional é uma importante área de pesquisa no contexto da Computação Científica. Através da modelagem e simulação das propriedades de líquidos e gases é possível obter resultados numéricos para diferentes estruturas e fenômenos físicos cotidianos e de grande importância econômica. A evolução dos sistemas computacionais possibilitou a essa área o surgimento de novas técnicas e abordagens de simulação. Uma das técnicas computacionais atualmente empregadas é o Método de Lattice Boltzmann, um método numérico iterativo para a modelagem e simulação mesoscópica da dinâmica de fluxos de fluidos. Diferentes tipos de sistemas físicos podem ser tratados através dessa técnica, como é o caso de fluxos em meios porosos ou de substâncias imiscíveis. No entanto, por causa da dimensão dos sistemas físicos, é necessário adotar estratégias que permitam a obtenção de resultados precisos ou em tempos computacionais aceitáveis. Assim, paralelizar as operações é a solução mais indicada para aumentar o desempenho do método. Uma maneira eficiente de paralelizar um método numérico é fazer uso de técnicas de distribuição de dados refinadas, como é o caso do particionamento em blocos. Tais abordagens de paralelização foram adotadas neste trabalho em implementações bi- e tridimensionais do Método de Lattice Boltzmann...

‣ Modelagem da interação fluido-sólido para simulação de molhabilidade e capilaridade usando o modelo Lattice-Boltzmann

Wolf, Fabiano Gilberto
Fonte: Florianópolis, SC Publicador: Florianópolis, SC
Tipo: Tese de Doutorado Formato: 1 v.| il., grafs., tabs.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Mecânica; O estudo de problemas que envolvem a molhabilidade e a capilaridade em meios porosos tem sido assunto de grande interesse científico e econômico. A importância desse estudo é revelada por muitos processos tecnológicos que incluem a aplicação direta de fluidos sobre diferentes tipos de superfícies. O principal objetivo desta tese de doutorado é o melhor entendimento destes fenômenos físicos. Com esse enfoque, um método Lattice-Boltzmann baseado em mediadores de campo é proposto para a simulação de fenômenos que envolvem a interação fluido-sólido, no qual os efeitos das forças de interação de longa distância são importantes e devem ser considerados para que a dinâmica macroscópica observada experimentalmente seja recuperada. A modelagem da interação fluido-fluido foi feita através de um modelo conhecido na literatura. Este modelo possibilita a simulação de equilíbrio de fases através de uma equação de estado que possui um comportamento semelhante à equação de van der Waals. Os resultados obtidos mostram que o ângulo de contato depende fortemente das interações de longa distância e o aumento das forças de adesão leva à diminuição do ângulo de contato...

‣ Formação e dinâmica da interface líquido-vapor simulada pelo método Lattice-Boltzmann

Wolf,Fabiano G.; Santos,Luis O.E. dos; Philippi,Paulo C.
Fonte: Sociedade Brasileira de Física Publicador: Sociedade Brasileira de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2006 Português
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O método Lattice-Boltzmann (LB) tem sido utilizado como um modelo alternativo para a simulação computacional da dinâmica de fluidos regida pelas equações de Navier-Stokes. É fundamentado na equação de transporte de Boltzmann, que serve como base da teoria cinética. Devido ao seu grande potencial para a análise de problemas com geometrias complexas, tem sido amplamente aplicado para a descrição de escoamentos de fluidos com um ou mais componentes em meios porosos, principalmente para o estudo de fenômenos interfaciais. Neste trabalho, um modelo LB com potencial de interação entre partículas foi utilizado para a modelagem da interface líquido-vapor. Este método possibilita a simulação de equilíbrio de fases através de uma equação de estado que possui o comportamento semelhante à equação de van der Waals. O método também permite a inclusão de termos de interação entre partículas distintas, de modo que as interfaces líquido-sólido e vapor-sólido podem ser facilmente simuladas. Alguns resultados de simulação são apresentados para problemas que envolvem a transição de fase líquido-vapor, a coexistência de uma gota líquida com seu vapor e a molhabilidade de superfícies sólidas. Adicionalmente...

‣ Performance Analysis of the Lattice Boltzmann Model Beyond Navier-Stokes

Randles, Amanda Peters; Kale, Vivek; Hammond, Jeff; Gropp, William; Kaxiras, Efthimios
Fonte: Institute of Electrical and Electronic Engineers Publicador: Institute of Electrical and Electronic Engineers
Tipo: Conference Paper
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The lattice Boltzmann method is increasingly important in facilitating large-scale fluid dynamics simulations. To date, these simulations have been built on discretized velocity models of up to 27 neighbors. Recent work has shown that higher order approximations of the continuum Boltzmann equation enable not only recovery of the Navier-Stokes hydrodynamics, but also simulations for a wider range of Knudsen numbers, which is especially important in micro- and nanoscale flows. These higher-order models have significant impact on both the communication and computational complexity of the application. We present a performance study of the higherorder models as compared to the traditional ones, on both the IBM Blue Gene/P and Blue Gene/Q architectures. We study the tradeoffs of many optimizations methods such as the use of deep halo level ghost cells that, alongside hybrid programming models, reduce the impact of extended models and enable efficient modeling of extreme regimes of computational fluid dynamics.; Physics

‣ Modeling Cardiovascular Hemodynamics Using the Lattice Boltzmann Method on Massively Parallel Supercomputers

Randles, Amanda Elizabeth
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
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Accurate and reliable modeling of cardiovascular hemodynamics has the potential to improve understanding of the localization and progression of heart diseases, which are currently the most common cause of death in Western countries. However, building a detailed, realistic model of human blood flow is a formidable mathematical and computational challenge. The simulation must combine the motion of the fluid, the intricate geometry of the blood vessels, continual changes in flow and pressure driven by the heartbeat, and the behavior of suspended bodies such as red blood cells. Such simulations can provide insight into factors like endothelial shear stress that act as triggers for the complex biomechanical events that can lead to atherosclerotic pathologies. Currently, it is not possible to measure endothelial shear stress in vivo, making these simulations a crucial component to understanding and potentially predicting the progression of cardiovascular disease. In this thesis, an approach for efficiently modeling the fluid movement coupled to the cell dynamics in real-patient geometries while accounting for the additional force from the expansion and contraction of the heart will be presented and examined. First, a novel method to couple a mesoscopic lattice Boltzmann fluid model to the microscopic molecular dynamics model of cell movement is elucidated. A treatment of red blood cells as extended structures...

‣ Simulation of Rising Bubbles Dynamics Using the Lattice Boltzmann Method

Ngachin, Merlin
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
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The main purpose of this thesis was to propose and test a new approach that captures the features of single and multiple bubbles dynamics using the Shan and Chen-type lattice Boltzmann method (LBM). Two dimensional bubbles motions were simulated considering the buoyancy effect for which the topology of the bubble is characterized by the Eötvös (Eo), and Morton (M) numbers. A qualitative and quantitative validation were performed using the Level set method. Bubble shape deformation was captured and analysis based on terminal Reynolds number and degree of circularity show very good agreement with the experimental results and with available simulation results. In sum, this study presents crucial preliminary information to further analyze multiphase fluid flows in various contexts.

‣ Lattice Boltzmann Modeling and Specialized Laboratory Techniques to Determine the Permeability of Megaporous Karst Rock

Garcia, Sade Maria
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
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The Pleistocene carbonate rock Biscayne Aquifer of south Florida contains laterally-extensive bioturbated ooltic zones characterized by interconnected touching-vug megapores that channelize most flow and make the aquifer extremely permeable. Standard petrophysical laboratory techniques may not be capable of accurately measuring such high permeabilities. Instead, innovative procedures that can measure high permeabilities were applied. These fragile rocks cannot easily be cored or cut to shapes convenient for conducting permeability measurements. For the laboratory measurement, a 3D epoxy-resin printed rock core was produced from computed tomography data obtained from an outcrop sample. Permeability measurements were conducted using a viscous fluid to permit easily observable head gradients (~2 cm over 1 m) simultaneously with low Reynolds number flow. For a second permeability measurement, Lattice Boltzmann Method flow simulations were computed on the 3D core renderings. Agreement between the two estimates indicates an accurate permeability was obtained that can be applied to future studies.

‣ Lattice Boltzmann Modeling of Fluid Flow and Solute Transport in Karst Aquifers

Anwar, Shadab
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
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A novel modeling approach is applied to karst hydrology. Long-standing problems in karst hydrology and solute transport are addressed using Lattice Boltzmann methods (LBMs). These methods contrast with other modeling approaches that have been applied to karst hydrology. The motivation of this dissertation is to develop new computational models for solving ground water hydraulics and transport problems in karst aquifers, which are widespread around the globe. This research tests the viability of the LBM as a robust alternative numerical technique for solving large-scale hydrological problems. The LB models applied in this research are briefly reviewed and there is a discussion of implementation issues. The dissertation focuses on testing the LB models. The LBM is tested for two different types of inlet boundary conditions for solute transport in finite and effectively semi-infinite domains. The LBM solutions are verified against analytical solutions. Zero-diffusion transport and Taylor dispersion in slits are also simulated and compared against analytical solutions. These results demonstrate the LBM’s flexibility as a solute transport solver. The LBM is applied to simulate solute transport and fluid flow in porous media traversed by larger conduits. A LBM-based macroscopic flow solver (Darcy’s law-based) is linked with an anisotropic dispersion solver. Spatial breakthrough curves in one and two dimensions are fitted against the available analytical solutions. This provides a steady flow model with capabilities routinely found in ground water flow and transport models (e.g....

‣ Lattice Boltzmann Method for Flow and Heat Transfer in Microgeometries

Gokaltun, Seckin
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
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Recent technological developments have made it possible to design various microdevices where fluid flow and heat transfer are involved. For the proper design of such systems, the governing physics needs to be investigated. Due to the difficulty to study complex geometries in micro scales using experimental techniques, computational tools are developed to analyze and simulate flow and heat transfer in microgeometries. However, conventional numerical methods using the Navier-Stokes equations fail to predict some aspects of microflows such as nonlinear pressure distribution, increase mass flow rate, slip flow and temperature jump at the solid boundaries. This necessitates the development of new computational methods which depend on the kinetic theory that are both accurate and computationally efficient. In this study, lattice Boltzmann method (LBM) was used to investigate the flow and heat transfer in micro sized geometries. The LBM depends on the Boltzmann equation which is valid in the whole rarefaction regime that can be observed in micro flows. Results were obtained for isothermal channel flows at Knudsen numbers higher than 0.01 at different pressure ratios. LBM solutions for micro-Couette and micro-Poiseuille flow were found to be in good agreement with the analytical solutions valid in the slip flow regime (0.01 < Kn < 0.1) and direct simulation Monte Carlo solutions that are valid in the transition regime (0.1 < Kn < 10) for pressure distribution and velocity field. The isothermal LBM was further extended to simulate flows including heat transfer. The method was first validated for continuum channel flows with and without constrictions by comparing the thermal LBM results against accurate solutions obtained from analytical equations and finite element method. Finally...

‣ Thermal Lattice Boltzmann Simulation for Rarefied Flow in Microchannels

Lopez, Pedro
Fonte: Universidade Rice Publicador: Universidade Rice
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This dissertation provides a detailed description of a new thermal lattice Boltzmann model capable of simulating temperature and velocity gradients within micro/nano-channels and vertical cavities in rarefied flow extending to the high end of the transition flow regime. The lattice Boltzmann method was selected to perform this study due to its applicability to the rarefied conditions expected in such small scale scenarios. An introduction is first included to provide details on the origins and derivation of the lattice Boltzmann method, including the various aspects that are required to successfully perform a simulation, namely boundary conditions, lattice velocity sets, methods to determine relaxation times, and strategies for capturing velocity as well as temperature fields. This is followed by a description of the thermal lattice Boltzmann method used as the basis for this study, as well as the determination of the method used to incorporate effects of walls on the calculation of the relaxation times. The applicability of this method is validated by incorporating two wall-distance functions based on exponential and power law relationships and simulating isothermal as well as thermally-affected cases. Next, a novel wall-distance function is derived to extend the applicability of our thermal lattice Boltzmann model to the entire transition flow regime. The method through which the function is derived is thoroughly described...

‣ Lattice-Boltzmann permeability of sphere packs undergoing diagenesis

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
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For a broad range of applications the most important transport property of porous media is permeability. Here we calculate the permeability and porosity of ordered sphere packs, simple, body-centered and face-centered cubic, as simple diagenetic processes reduces their pore spaces. For diagenesis we use simple geometrical models including compaction by plastic deformation, compaction by pressure solution, consolidation of cementation, consolidation by surface precipitation and temporary consolidation by capillary action until porosity becomes isolated. For flow simulations at selected porosity levels we use the lattice-Boltzmann method with a 15-speed and 19-speed models on three dimensional lattices. For validation purposes, the lattice-Boltzmann method is compared against an explicit finite-difference method for incompressible flow in simpler geometries. Simulating slow creeping flow through three-dimensional channels of different polygonal cross sections and three-dimensional porous structures of intermediate complexity checked the accuracy of the lattice-Boltzmann scheme used. We explore pore space microstructure transitions and universal character of the permeability-porosity relationships obtained.

‣ Permeability-porosity relationship from a geometrical model of shrinking and lattice Boltzmann and Monte Carlo simulations of flow in two-dimensional pore networks

Fonte: Universidade Católica de Temuco Publicador: Universidade Católica de Temuco
Tipo: Artículo de Revista
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For a broad range of applications, the most important transport property of porous media is permeability. Here we calculate the permeability of pore network approximations of porous media as simple diagenetic or shrinking processes reduces their pore spaces. We use a simple random bond-shrinkage mechanism by which porosity is decreased; a tube is selected at random and its radius is reduced by a fixed factor, the process is repeated until porosity is reduced either to zero or a preset value. For flow simulations at selected porosity levels, we use precise Monte Carlo calculations and the lattice Boltzmann method with a 9-speed model on two-dimensional square lattices. Calculations show a simple power-law behavior, k ∝ φm, where k is the permeability and φ the porosity. The value of m relates strongly to the shrinking process and extension, and hence to the skewness of the pore size distribution, which varies with shrinking, and weakly to pore sizes and shapes. Smooth shrinking produces pore space microstructures resembling the starting primitive material; one value of m suffices to describe k versus φ for any value of porosity. Severe shrinking however produces pore space microstructures that apparently forget their origin; the k-φ curve is only piecewise continuous...

‣ Validation of the Lattice Boltzmann Method for Direct Numerical Simulation of Wall-Bounded Turbulent Flows

BESPALKO, DUSTIN JOHN
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
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In this work, the lattice Boltzmann method (LBM) was validated for direct numerical simulation (DNS) of wall-bounded turbulent flows. The LBM is a discrete-particle-based method that numerically solves the Boltzmann equation as opposed to conventional DNS methods that are based on the Navier-Stokes (NS) equations. The advantages of the LBM are its simple implementation, its ability to handle complex geometries, and its scalability on modern high-performance computers. An LBM code was developed and used to simulate fully-developed turbulent channel flow. In order to validate the results, the turbulence statistics were compared to those calculated from a conventional NS-based finite difference (FD) simulation. In the present study, special care was taken to make sure the computational domains for LBM and FD simulations were the same. Similar validation studies in the literature have used LBM simulations with smaller computational domains in order to reduce the computational cost. However, reducing the size of the computational domain affects the turbulence statistics and confounds the results of the validation. The turbulence statistics calculated from the LBM and FD simulations were found to agree qualitatively; however, there were several significant deviations...

‣ Direct numerical simulation of complex viscoelastic flows via fast lattice-Boltzmann solution of the Fokker–Planck equation

BERGAMASCO, Luca; IZQUIERDO, Salvador; AMMAR, Amine
Fonte: ELSEVIER Publicador: ELSEVIER
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Micro–macro simulations of polymeric solutions rely on the coupling between macroscopic conservation equations for the fluid flow and stochastic differential equations for kinetic viscoelastic models at the microscopic scale. In the present work we introduce a novel micro–macro numerical approach, where the macroscopic equations are solved by a finite-volume method and the microscopic equation by a lattice-Boltzmann one. The kinetic model is given by molecular analogy with a finitely extensible non-linear elastic (FENE) dumbbell and is deterministically solved through an equivalent Fokker–Planck equation. The key features of the proposed approach are: (i) a proper scaling and coupling between the micro lattice-Boltzmann solution and the macro finite-volume one; (ii) a fast microscopic solver thanks to an implementation for Graphic Processing Unit (GPU) and the local adaptivity of the lattice-Boltzmann mesh; (iii) an operator-splitting algorithm for the convection of the macroscopic viscoelastic stresses instead of the whole probability density of the dumbbell configuration. This latter feature allows the application of the proposed method to non-homogeneous flow conditions with low memory-storage requirements. The model optimization is achieved through an extensive analysis of the lattice-Boltzmann solution...

‣ Condiciones De Contorno De Flujos Totalmente Desarrollados Para El Método De Lattice Boltzmann

Dottori, Javier Alejandro; Boroni, Gustavo Adolfo; Lazo, Marcos Gonzalo; Garcia Bauza, Cristian Dario; Clausse, Alejandro
Fonte: Asociación Argentina de Mecánica Computacional Publicador: Asociación Argentina de Mecánica Computacional
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
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El método de Lattice Boltzmann (LBM) es un esquema numérico, que opera en un espacio de variables discretas vectoriales internas con más grados de libertad que las estrictamente necesarias para representar un flujo a nivel macroscópico. Para contraer la solución a las variables observables se utiliza una función de cierre, llamada ecuación de equilibrio, que asegura una aproximación a segundo grado de las ecuaciones de transporte correspondientes. En particular, el modelo de Bhatnagar-GrossKrook (BGK) permite simular las ecuaciones de Navier-Stokes. Sin embargo, las condiciones de contorno requieren especial cuidado para conservar el orden de convergencia y disminuir el error del método. En este trabajo se presenta un estudio del tratamiento de las condiciones de contorno de LBM a la salida de un flujo totalmente desarrollado. Se analizan los métodos más utilizados y se propone una solución basada en la maximización de la entropía. Luego de realizar tres estudios numéricos sobre canales rectos con y sin fuerza transversal, se concluyó que la solución propuesta permite obtener mejores resultados sobre las variables macroscópicas observadas en problemas de flujos desarrollados. De esta manera, se pueden realizar experimentos con canales de menor longitud...

‣ An Improved Immersed-Boundary Algorithm for Fluid-Solid Interaction un Lattice-Boltzmann Simulations

Boroni, Gustavo Adolfo; Dottori, Javier Alejandro; Dalponte, Diego David; Rinaldi, Pablo Rafael; Clausse, Alejandro
Fonte: Plapiqui (uns-conicet) Publicador: Plapiqui (uns-conicet)
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
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An improved algorithm combining the features of the lattice Boltzmann and the immersed-boundary methods is presented. Following previous formulations, the method represents a fluid con-strained by flexible boundaries by means of a force term acting on the cells adjacent to the boundary, which in turn is moved by the fluid. The present al-gorithm introduces a more efficient iteration proce-dure to calculate the fluid-boundary interaction, which facilitates the implementation. The simulations where validated against experimental and analytical data showing good agreement and demonstrating the performance of the method to simulate different kind of fluid-solid interaction; Fil: Boroni, Gustavo Adolfo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Grupo de Plasmas Densos Magnetizados; Argentina;; Fil: Dottori, Javier Alejandro. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Grupo de Plasmas Densos Magnetizados; Argentina;; Fil: Dalponte, Diego David. Comisión Nacional de Energía Atómica, Argentina.;; Fil: Rinaldi, Pablo Rafael. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Grupo de Plasmas Densos Magnetizados; Argentina;; Fil: Clausse...

‣ Lattice-Boltzmann method applied to the pattern formation on periodic surface structures generated by multiline nanosecond laser

Fonseca-Fonseca,Frank Rodolfo; Alfonso-Orjuela,José Edgar; Andrade,Darío Fernando
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 Português
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We simulated the pattern formation on silicon surfaces. For this purpose, we used Lattice-Boltzmann method assuming two non-ideal interacting fluids using a lattice velocity D2Q9. The experiment was carried out with a multiline (1064, 532 and 355 nm) Nd: YAG pulsed laser that employs an energy range from 310 to 3100 J on a surface p-type monocrystalline silicon oriented in the direction [111]. The whole system was subjected to argon gas blowing which is key in pattern formation. Computer simulation reproduces the overall behavior of the experimental geometric patterns expressed in oblique parallel ripples quite well.