In this thesis the validation of a computational fluid dynamics (CFD) code against published experimental data and alternative CFD results is explored. Six case studies are presented with flow speeds ranging from mid supersonic to hypersonic. The studies include complex compressible flow phenomena such as the interaction of shockwaves with boundary layers, vortices and other shockwaves. Two of the six validation cases also consider complex thermodynamic behaviour such as vibrational and chemical nonequilibrium. The problems chosen are limited in scope to flows which are planar or axisymmetric and remain laminar throughout the region of flow studied. This allows the studies to focus on simulating the fundamental behaviour of the flow without the added complication of turbulence or the need for large scale computing facilities. The problems which arose during the validation studies and a background to why they occurred and, wherever possible, strategies to avoid their occurrence are discussed. General modelling strategies in compressible CFD are also discussed. In this thesis the software suite CFD-FASTRAN is used to construct and analyse the CFD models. The material presented in this thesis is however general such that users of similar packages should find the thesis beneficial.

In this thesis the validation of a computational fluid dynamics (CFD) code against published experimental data and alternative CFD results is explored. Six case studies are presented with flow speeds ranging from mid supersonic to hypersonic. The studies include complex compressible flow phenomena such as the interaction of shockwaves with boundary layers, vortices and other shockwaves. Two of the six validation cases also consider complex thermodynamic behaviour such as vibrational and chemical nonequilibrium. The problems chosen are limited in scope to flows which are planar or axisymmetric and remain laminar throughout the region of flow studied. This allows the studies to focus on simulating the fundamental behaviour of the flow without the added complication of turbulence or the need for large scale computing facilities. The problems which arose during the validation studies and a background to why they occurred and, wherever possible, strategies to avoid their occurrence are discussed. General modelling strategies in compressible CFD are also discussed. In this thesis the software suite CFD-FASTRAN is used to construct and analyse the CFD models. The material presented in this thesis is however general such that users of similar packages should find the thesis beneficial.

In this thesis the validation of a computational fluid dynamics (CFD) code against published experimental data and alternative CFD results is explored. Six case studies are presented with flow speeds ranging from mid supersonic to hypersonic. The studies include complex compressible flow phenomena such as the interaction of shockwaves with boundary layers, vortices and other shockwaves. Two of the six validation cases also consider complex thermodynamic behaviour such as vibrational and chemical nonequilibrium. The problems chosen are limited in scope to flows which are planar or axisymmetric and remain laminar throughout the region of flow studied. This allows the studies to focus on simulating the fundamental behaviour of the flow without the added complication of turbulence or the need for large scale computing facilities. The problems which arose during the validation studies and a background to why they occurred and, wherever possible, strategies to avoid their occurrence are discussed. General modelling strategies in compressible CFD are also discussed. In this thesis the software suite CFD-FASTRAN is used to construct and analyse the CFD models. The material presented in this thesis is however general such that users of similar packages should find the thesis beneficial.

Made available in DSpace on 2016-12-12T20:25:11Z (GMT). No. of bitstreams: 1 Samuel Santos Borges.pdf: 6941803 bytes, checksum: b35255a08a379f33b11c0304b0a24acb (MD5) Previous issue date: 2013-09-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work consists in an analysis of the noise level generated by axial flow fans composed of centrifugal rotors with radial blades, where the main objective is the development and validation of a methodology for the prediction of the aerodynamic noise generated by these fans. The proposed methodology was developed based on works available in the literature, in which the emitted sound power level is calculated through analytical equations that use experimentally calibrated parameters and variables related to the fan operating point, such as volume flow, pressure, absorbed power, peripheral velocity, among others. The fan aerodynamic variables were obtained with the aid of CFD techniques, which require a validation process. This validation process is accomplished by means of the comparison between the CFD and experimental results. The methodology validation is achieved by the comparison between the predicted and the experimental results of the sound pressure levels and the fan aerodynamic variables. All experiments involved in the present work were carried out following the procedures and criteria established by technical standards. The main acoustic resonance modes of the fan were also determined by means of the numerical simulations and validated through experimental sound measurement techniques of the type Waterfall. / Este trabalho consiste em uma análise do nível de ruído gerado por ventiladores de fluxo axial composto por rotores centrífugos de pás radiais, onde o principal objetivo é o desenvolvimento e a validação de uma metodologia para predição do nível de ruído aerodinâmico gerado por tais ventiladores. O desenvolvimento do método proposto é fundamentado em trabalhos disponíveis na literatura, onde o nível de potência sonora emitida por ventiladores é calculado através de equações analíticas que usam parâmetros calibrados experimentalmente e variáveis relacionadas ao ponto de operação do ventilador, como vazão, pressão, potência absorvida, velocidade periférica, entre outros. As variáveis aerodinâmicas do ventilador foram obtidas com o auxílio de técnicas de CFD, as quais necessitam de um processo de validação. Esse processo é executado por meio da comparação entre os resultados de CFD e experimentais. A validação da metodologia é realizada pela comparação entre os resultados preditos e os experimentais dos níveis de pressão sonora e das variáveis aerodinâmicas do ventilador. Todos os experimentos envolvidos no presente trabalho foram executados conforme procedimentos e critérios estabelecidos por normas técnicas. Os principais modos de ressonância acústica do ventilador também foram determinados por meio de simulações numéricas e validadas através de técnicas de medição sonora experimental do tipo Waterfall.

Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-08-20T19:12:54Z No. of bitstreams: 1 BRUNO OLIVEIRA LOPES – DISSERTAÇÃO (PPGEM) 2018.pdf: 2679561 bytes, checksum: 17af196ea163d4dbc0b28512ae9edb45 (MD5) / Made available in DSpace on 2018-08-20T19:12:54Z (GMT). No. of bitstreams: 1 BRUNO OLIVEIRA LOPES – DISSERTAÇÃO (PPGEM) 2018.pdf: 2679561 bytes, checksum: 17af196ea163d4dbc0b28512ae9edb45 (MD5) Previous issue date: 2018-02-23 / A mineração é uma atividade econômica relevante em diversos países. No tratamento de minérios, a água é um insumo indispensável. Para a classificação de minérios, a indústria mineral tem usado o processo de hidrociclonagem, onde a água é utilizada como meio para o transporte de partículas de minério dispersas, que são separadas do líquido através da força centrífuga no interior do equipamento denominado de hidrociclone. O avanço constante do poder de processamento dos computadores em conjunto com a evolução nas técnicas e métodos numéricos tem permitido simular com grande precisão problemas complexos de fluidodinâmica tal qual o escoamento em hidrociclones. Neste sentido, este trabalho tem como objetivo estudar o processo de separação de partículas de minério em hidrociclones via software Ansys Fluent. Para a simulação fluidodinâmica utilizou-se uma modelagem matemática baseada em uma análise Euleriana-Lagrangeana. Resultados dos campos de pressão, velocidade, e fração volumétrica das fases, eficiência do processo de separação em diversas condições operacionais são apresentados e avaliados. Dos resultados verificou-se que o aumento da velocidade de escoamento na entrada do equipamento tende a aumentar o desempenho do hidrociclone na eficiência de separação até certo limite / Mining is a relevant economic activity in many countries. In the treatment of ores, water is an indispensable input. For the classification of ores, the mineral industry has used the hydrocyclone process, where water is used as the medium for transporting dispersed ore particles, which are separated from the liquid by centrifugal force inside the so-called hydrocyclone equipment. The constant advance of the processing power of the computers together with the evolution in the techniques and numerical methods has allowed to simulate with great precision complex problems of fluidodynamics like the flow in hydrocyclones. In this sense, this work aims to study the process of separation of ore particles in hydrocyclones using Ansys Fluent software. For the fluid dynamics simulation, a mathematical model based on an Eulerian-Lagrangian analysis was used. Results of pressure, velocity, and volumetric fraction phases, efficiency of the separation process under various operational conditions are presented and evaluated. From the results it has been found that increasing the flow velocity at the inlet of the equipment tends to increase the performance of the hydrocyclone in the separation efficiency to a certain extent.

Les turbines à gaz modernes deviennent de plus en plus compactes, ce qui augmente les interactions entre leurs différents composants. Les interactions chambre de combustion-turbine sont particulièrement critiques car elles peuvent changer le champ aérothermique dans la turbine et réduire la durée de vie du moteur. Aujourd’hui, ces deux composants sont traités de façon indépendante, ce qui ne permet pas de prendre en compte leurs interactions. Cette thèse propose une approche couplée, basée sur les Simulations aux Grandes Échelles (SGE), une technique qui permet de prendre en compte toutes les interactions chambre de combustion-turbine. Dans la première partie de cette thèse, une méthode, compatible avec le code SGE AVBP, est proposée pour traiter les configurations rotor/stator de manière rigoureuse. Une série de cas test académiques vient prouver que l’interface respecte les propriétés des schémas numériques du code. Cette étude est suivie par une validation de l’approche dans le cas d'une turbine haute-pression mono-étage. Les résultats sont comparés avec des mesures expérimentales et l’influence des différents paramètres et modèles est établi. La deuxième partie de cette travail est dédiée à la prédiction des interactions chambre de combustion-turbine en utilisant les méthodes précédemment décrites et validées. Le premier type d’interaction étudié est la génération du bruit de combustion indirect dans une turbine haute pression. Ce bruit est créé lorsque des hétérogénéités de température, générées dans la chambre de combustion, sont accélérées dans la turbine. Pour simplifier les calculs, les hétérogénéités sont modélisées par des fluctuations de température sinusoïdales, injectées dans la turbine par les conditions limites. Les mécanismes de génération de bruit sont mis en évidence et le bruit de combustion indirect est mesuré et comparé avec une théorie analytique et des prédictions 2D. La deuxième application est un calcul couplé chambre de combustion-turbine qui analyse les interactions entre ces deux composants d’un point de vue aérothermique. Les caractéristiques instationnaires de l’écoulement à l’entrée de la turbine et la migration des hétérogénéités de température dans la turbine sont étudiées. Un calcul de la turbine seule est aussi effectué pour comparaison avec le calcul couplé. / Modern gas turbines are characterized by compact designs that enhance the interactions between its different components. Combustion chamber-turbine interactions, in particular, are critical as they may alter the aerothermal flow field of the turbine which can drastically impact the engine life duration. Current state-of-the-art treats these two components in a decoupled way and does not take into account their interactions. This dissertation proposes a coupled approach based on the high-fidelity Large Eddy Simulation (LES) formalism that can take into account all the potential paths of interactions between components. In the first part of this work, an overset grid method is proposed to treat rotor/stator configurations in a rigorous fashion that is compatible with the LES solver AVBP. This interface treatment is shown not to impact the characteristics of the numerical schemes on a series of academic test cases of varying complexity. The approach is then validated on a realistic high-pressure turbine stage. The results are compared against experimental measurements and the influence of different modeling and simulation parameters is evaluated. The second part of this work is dedicated to the prediction of combustion chamber-turbine interactions using the developed methodologies. The first type of interactions evaluated is the indirect combustion noise generation across a high-pressure turbine stage. This noise arises when combustor-generated temperature heterogeneities are accelerated in the turbine. To simplify the simulations the heterogeneities are modeled by sinusoidal temperature fluctuations injected in the turbine through the boundary conditions. The noise generation mechanisms are revealed by such LES and the indirect combustion noise is measured and compared to an analytical theory and 2D predictions. The second application is a fully-coupled combustor-turbine simulation that investigates the interactions between the two components from an aerothermal point of view. The rich flow characteristics at the turbine inlet, issued by the unsteady combustion in the chamber, are analyzed along with the migration of the temperature heterogeneities. A standalone turbine simulation serves as a benchmark to compare the impact of the fully coupled approach.

Dans un contexte d'amélioration des moteurs aéronautiques en termes de consommation et de pollution, les simulations numériques apparaissent comme un outil intéressant pour mieux comprendre et modéliser les phénomènes turbulents qui se produisent dans les turbomachines. La simulation aux grandes échelles (SGE) d’un étage de turbomachine à des conditions réalistes (nombre de Mach, nombre de Reynolds…) reste toutefois hors de portée dans le cadre industriel. La méthode chorochronique, aujourd’hui largement utilisée pour les calculs URANS, permet de réduire le coût des simulations numériques, mais elle implique de stocker le signal aux frontières du domaine pendant une période complète de l’écoulement. Le stockage direct de l’information étant exclu étant donné la taille des maillages et les pas de temps mis en jeu, la solution la plus courante actuellement est de décomposer le signal sous la forme de séries de Fourier. Cette solution ne retient du signal qu’une fréquence fondamentale (la fréquence de passage de la roue opposée) et un nombre limité d’harmoniques. Dans le cadre d’une SGE, elle implique donc une grande perte d’énergie, et le filtrage des phénomènes décorrélés de la vitesse de rotation comme par exemple un lâcher tourbillonnaire. Le remplacement de la décomposition en séries de Fourier par une décomposition aux valeurs propres (POD pour Proper Orthogonal Decomposition) permet de stocker le signal aux interfaces sans faire d’hypothèse sur les fréquences contenues dans le signal et donc de réduire la perte d’énergie liée à l’utilisation d’un modèle réduit. La compression s’effectue en supprimant les plus petites valeurs singulières et les vecteurs associés. Cette nouvelle méthode est validée sur la simulation URANS d'étages de turbomachines et comparée aux conditions classiques utilisant les séries de Fourier et à des calculs de références contenant plusieurs aubes par roue. Elle est ensuite appliquée à la simulation aux grandes échelles de l'écoulement d'un cylindre. Les erreurs causées par l'hypothèse chorochronique et par la compression sont séparées et on montre que l'utilisation de la POD permet de réduire de moitié le filtrage des fluctuations de vitesses par rapport aux séries de Fourier pour un même taux de compression. Enfin, la simulation aux grandes échelles d'un étage de turbomachine avec des conditions chorochroniques POD est réalisée afin de valider la méthode dans le cadre d'une configuration industrielle. / The more and more restrictive standards in terms of fuel consumption and pollution for aircraft engines lead to a constant improvement of their design. Numerical simulations appear as an interesting tool for a better understanding and modeling of the turbulent phenomena which occur in turbomachinery. The large-eddy simulation (LES) of a turbomachinery stage at realistic conditions (Mach number, Reynolds number...) remains out of reach for industrial congurations. The phase-lagged method, widely used for unsteady Reynolds-averaged Navier--Stockes (URANS) calculations, is a good candidate to reduce the computational cost. However, it needs to store the signal at all the boundaries over a full passage of the opposite blade. A direct storage of the information being excluded given the size of the mesh grid and timesteps involved, the most used solution currently is to decompose the signal into Fourier series. This solution retains the fundamental frequency of the signal (the opposite blade passage frequency) and a limited number of harmonics. In the frame of a LES, as the spectra are broadband, it implies a loss of energy. Replacing the Fourier series decomposition by a proper orthogonal decomposition (POD) allows the storage of the signal at the interfaces without making any assumptions on the frequency content of the signal, and helps to reduce the loss of energy caused by the phase lagged method. The compression is done by removing the smallest singular values and the associated vectors. This new method is first validated on the URANS simulations of turbomachinery stages and compared with Fourier series-based conditions and references calculations with multiple blades per row. It is then applied to the large eddy simulation of the flow around a cylinder. The error caused by the phase-lagged assumption and compression are separated and it is showed that the use of the POD allows to halve the filtering of the velocity fluctuations with respect to the Fourier series, for a given compression rate. Finally, the large eddy simulation of a compressor stage with POD phase-lagged conditions is carried out to validate the method for realistic turbomachinery configurations.

Ce travail s’inscrit dans le projet LORVER, soutenu par la Région Grand Est et le FEDER. Il est destiné à créer une filière de production de biomasse végétale non alimentaire par valorisation de sites dégradés et de sous-produits industriels, en Lorraine. Un des procédés de valorisation de la biomasse produite est un procédé thermochimique de pyro-gazéification qui générerait de la chaleur et de l’électricité. Ce procédé, développé par SEA Marconi, se compose de trois réacteurs différents : un tambour tournant, pour la pyrolyse de particules de bois, la chaleur étant amenée par des billes d’acier chauffées ; un réacteur à vis sans fin pour l’oxydation du char qui permet de réchauffer les billes d’acier ; un réacteur de craquage des goudrons. L’objectif de cette thèse est de réaliser des modèles qui puissent permettre d’avoir une prédiction adaptée du comportement du système. Des modèles 3D du type DEM et CFD-DEM ont été conçus pour la modélisation des phénomènes qui interviennent dans le système. Les paramètres du modèle DEM ont été calibrés dans un tambour tournant de laboratoire. Pour le réacteur de pyrolyse, la simulation DEM a permis de prédire de façon satisfaisante la ségrégation pour des mélanges de billes d’acier et de particules non sphériques de bois, et de concevoir un modèle thermique et chimique 1D, sur lequel une étude de sensibilité a été effectuée. Un modèle CFD-DEM a été codé et validé sur un rhéomètre granulaire, permettant la simulation du réacteur d’oxydation partielle du char, qui n’a pas pu être réalisé dans le cadre de cette thèse / This work is part of the LORVER project, funded by Grand Est Région and FEDER. It aims to create a non-food biomass production chain by using and upgrading brownfields and industrial by-products in Lorraine. One possible valorization process of the produced biomass is a thermochemical pyro-gasification process that would generate heat and electricity. This process, developed by SEA Marconi, involves three different reactors: a rotating drum, for the pyrolysis of wood particles, the heat required being brought by hot steel balls; an Auger for partial oxidation of the char that allows heating the steel balls; a reactor for tar cracking. The aim of this thesis is to develop models that can predict the behavior of the system. 3D models based on DEM or CFD - DEM were designed for the modeling of phenomena involved in the system. The DEM model parameters were first calibrated in a rotating drum. The DEM simulation was able to predict in a satisfactory manner segregation between steel balls and non-spherical wood particles; it also helped to design a 1D thermal and chemical model, on which a sensitivity study has been done. A CFD - DEM model has been coded and validated on a granular rheometer allowing the simulation of the char oxidation reactor, even if this simulation was not possible during the PhD

Made available in DSpace on 2015-03-26T13:23:25Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1752790 bytes, checksum: 9fb5b25994a8d5253069bea8e07ae331 (MD5) Previous issue date: 2009-04-17 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The national crop production of grains from 2007 to 2008 was the largest in the history of Brazil, reaching 143.87 million of tons. Among this amount, maize grains respond for 40.7% (58.58 million of tons). The pest control in stored grains is carried out mainly by fumigation with fosfine. It is verified in literature that some insects has been developed resistance to fosfine, and there is no practical fumigant available. The ozone gas is a strong oxidant and it consists on a new technology with great potential for pest control in stored grains. Due to the size of the Brazilian structures for grain storage, experimental tests with alternative fumigants are essentially costly, so the computational fluid mechanics (CFD) arises as a powerful tool for prediction and design injection systems for ozone gas. The aim of this study was the modeling and simulation of injection systems for ozone gas for maize grains stored in a commercial bin using the CFD technique applied to porous media. Two one-dimensional cases of mass transport by convection-diffusion and diffusion-reaction, in which the exact solutions were known, were employed to validate the CFD model. The effects of Péclet number and Thiele modulus on the mass transfer along the porous media were investigated. It was verified that for smaller Péclet numbers the gradient concentration tend to be smooth and constant along the porous media, and when the Péclet number increase, a mesh refinement should be made near the outlet. When the Thiele modulus increases, the concentration gradient for the ozone gas also increases due to its fast consumption by reaction when compared to the axial diffusion transport. The Thiele modulus for the ozone is 41, which means that the decomposition rate is greater than the diffusion rate in the grains mass. Thus, different from the application of fumigants such as the fosfine, the ozone should be injected by convection into the grains mass. For the convectiondiffusion- reaction transport of ozone gas in porous media, the decomposition and saturation kinetics were modeled and used in the CFD model. The ozone gas transport in the model was used to simulate the ozone gas in a fixed bed and the concentration profile was compared to experimental data reported by Kells et al. (2001). The simulation results show good agreement to experimental results and the associated error norm was low. Therefore, the proposed CFD model can be used for simulation of gas ozone injection systems in maize grains. The performance of two injection systems of ozone gas was compared using CFD simulation in a commercial storage bin. Two injection systems were simulated: injection at the base of the silo and using probes. A minimum injection rate of 1.27 kg s-1 and 9.50 kg s-1, for injection at the base and by probes, respectively, was required to reach 50 ppm of ozone in more than 95% of the grain mass. Thus, the injection by the base of the bin is more efficient since it require a smaller mass flow. The proposed model for the ozone transport in porous media is valid and it can be used in other studies of injection systems of ozone in stored grains. / A safra nacional de grãos 2007/2008 foi uma das maiores na história do Brasil, atingindo uma marca em torno de 143,87 milhões de toneladas, com destaque para o milho que responde por, aproximadamente, 40,7% (58,58 milhões de toneladas) deste total. O controle de pragas em grãos armazenados tem sido feito por meio de fumigação e a fosfina é o principal produto usado. São muito escassas as opções para substituir a fosfina, o que representa um grande risco de desenvolvimento de resistência dos insetos a esse produto. O gás ozônio, um forte oxidante, é uma nova tecnologia com potencial para o controle de pragas. Diante deste contexto e devido aos sistemas nacionais de armazenamento que tornam os testes experimentais essencialmente dispendiosos, a mecânica dos fluidos computacional (CFD) desponta como uma importante técnica para predição, manipulação e estudo dos processos de injeção do gás ozônio em sistemas de armazenamento de grãos. Sendo assim, objetivou-se com este trabalho modelar um sistema de injeção de gás ozônio para utilização em armazéns a granel utilizando a técnica de CFD aplicada a meios porosos. Foram modelados dois casos unidimensionais de transporte de massa por convecção-difusão e difusão-reação com soluções analíticas conhecidas. As simulações foram realizadas variando-se o número de Péclet (Pe), no primeiro caso, e o módulo de Thiele (λ), no segundo. Foram sugeridos e ajustados os modelos para a cinética de decomposição e saturação do ozônio. O terceiro caso foi um estudo do transporte de O3 em um leito fixo em que as medidas experimentais de Kells et al. (2001) foram comparadas com os resultados obtidos nas simulações. O quarto caso estudado foi um problema de transporte de ozônio em um leito fixo de milho em que foram avaliadas duas formas de injeção do gás ozônio em um silo de armazenamento. Para o primeiro caso, verificou-se que quanto menor o valor de Pe maior é o gradiente de concentração entre a entrada e saída da coluna (predomínio do termo difusivo). Observou-se que para elevados valores de Pe, um refinamento de malha deve ser efetuado. No segundo caso, verificou-se que, para altos valores do λ, os gradientes de concentração de ozônio são elevados e ocorre rápido consumo devido à reação (predomínio do fenômeno reativo em relação ao difusivo). O módulo de Thiele para o ozônio é 41, o que decorre em maior taxa de decomposição em relação à taxa de difusão na massa de grãos. Desta forma, diferente da aplicação de fumigantes tais como a fosfina, o ozônio deve ser aplicado por um fluxo convectivo. Os resultados obtidos pelo modelo proposto no terceiro caso apresentam um bom ajuste em relação aos resultados experimentais. O erro associado é baixo e a diferença em relação aos dados experimentais pode ser explicada pela diferença nas propriedades físicas do milho utilizadas. O modelo proposto é válido e possibilita a simulação de sistemas de injeção de ozônio em colunas. Foram simulados dois sistemas de injeção de ozônio: pela base do silo e por sondas. Para atingir a concentração de 50 ppm de ozônio (dose letal para insetos) em mais de 95 % da massa de grãos é necessária uma injeção mínima de ozônio pela base e por sonda de 1,27 kg s-1 e 9,50 kg s-1, respectivamente. Desta forma, conclui-se que a injeção pela base do silo é mais eficiente, pois requer um menor fluxo de massa. O modelo proposto para o transporte de ozônio em meios porosos é válido e pode ser utilizado em outros estudos de sistemas de injeção de ozônio em grãos.

A soleira lateral desempenha um papel importante nos reservatórios de detenção/ retenção (off-line), atuando na captação das vazões afluentes e evitando possíveis enchentes, problema em destaque nos períodos chuvosos das principais capitais brasileiras. Um melhor entendimento do seu comportamento hidráulico possibilitará o desenvolvimento de estruturas laterais mais eficientes. O presente trabalho tem como objetivo criar um modelo da soleira lateral através da tecnologia CFD (Dinâmica dos Fluidos Computacional) e validá-lo através de experimentos em modelo reduzido do Laboratório de Hidráulica da Escola Politécnica da USP. A partir disso, explorar as características hidráulicas do modelo de CFD, como o comportamento dos níveis dágua e a distribuição de velocidades. No estudo da validação estudaram-se três tipos de refinamento de malhas e três modelos de turbulência (k-, k- (RNG) e SST k-). O modelo computacional validado é composto pela malha 3, com um refinamento cerca de 342000 elementos (hexaédricos predominante), e o modelo de turbulência k- (RNG), que apresentaram a maior precisão dos resultados. A análise da distribuição de velocidades possibilitou visualizar uma região de mínima velocidade abaixo da soleira lateral, e também quantificar uma região de baixas velocidades no início da soleira, onde é pequena a eficiência das vazões escoadas. Através do comportamento da superfície dágua foi possível visualizar a região de influência do dispositivo lateral no canal principal. A comparação do coeficiente de descarga do modelo de CFD com trabalhos de outros pesquisadores, um nacional e outro internacional, mostrou a representatividade do modelo criado para condições diferentes. A ferramenta CFD é promissora para o estudo de estruturas hidráulicas, contribuindo para o seu desenvolvimento e aperfeiçoamento. / The side weir plays an important role in the detention / retention tanks (off-line), operating in the uptake of water inflow and preventing possible flooding, which is a highlighted problem on rainy periods of the main Brazilian capitals. A better understanding of the hydraulic behavior allows the development of more efficient lateral structures. This work aims at creating a model of the side weir through CFD technology (Computational Fluid Dynamics) and validating it through experiments on a reduced model of the Laboratório de Hidráulica da Escola Politécnica da USP. Thereafter, explore the hydraulic characteristics of the CFD model, like the behavior of water levels and the velocity distribution. In the validation study, three types of mesh refinement and three turbulence models were studied (k-, k- (RNG) and SST k-). The computational model is validated by the composite mesh 3 with a refinement about 342,000 elements (hexahedral predominant), and the turbulence model k- (RNG), which had the highest precision of results. Analysis of the velocities distribution allowed us to visualize a region of minimum velocity below the side weir, and also to quantify a region of low velocities at the beginning of the weir, where the efficiency of overflows is small. Through water surface behavior it was possible to visualize the influence region of the side device in the main channel. A comparison of discharge coefficient of the CFD model between other works (one national and the other one international) showed the representativeness of the model created for different conditions. The CFD is a promising tool for the study of hydraulic structures, contributing to its development and improvement.