abstract: ABSTRACT The heat recovery steam generator (HRSG) is a key component of Combined Cycle Power Plants (CCPP). The exhaust (flue gas) from the CCPP gas turbine flows through the HRSG − this gas typically contains a high concentration of NO and cannot be discharged directly to the atmosphere because of environmental restrictions. In the HRSG, one method of reducing the flue gas NO concentration is to inject ammonia into the gas at a plane upstream of the Selective Catalytic Reduction (SCR) unit through an injection grid (AIG); the SCR is where the NO is reduced to N2 and H2O. The amount and spatial distribution of the injected ammonia are key considerations for NO reduction while using the minimum possible amount of ammonia. This work had three objectives. First, a flow network model of the Ammonia Flow Control Unit (AFCU) was to be developed to calculate the quantity of ammonia released into the flue gas from each AIG perforation. Second, CFD simulation of the flue gas flow was to be performed to obtain the velocity, temperature, and species concentration fields in the gas upstream and downstream of the SCR. Finally, performance characteristics of the ammonia injection system were to be evaluated. All three objectives were reached. The AFCU was modeled using JAVA - with a graphical user interface provided for the user. The commercial software Fluent was used for CFD simulation. To evaluate the efficacy of the ammonia injection system in reducing the flue gas NO concentration, the twelve butterfly valves in the AFCU ammonia delivery piping (risers) were throttled by various degrees in the model and the NO concentration distribution computed for each operational scenario. When the valves were kept fully open, it was found that it led to a more uniform reduction in NO concentration compared to throttling the valves such that the riser flows were equal. Additionally, the SCR catalyst was consumed somewhat more uniformly, and ammonia slip (ammonia not consumed in reaction) was found lower. The ammonia use could be decreased by 10 percent while maintaining the NO concentration limit in the flue gas exhausting into the atmosphere. / Dissertation/Thesis / M.S. Mechanical Engineering 2011

Les décollements autour d’un corps en mouvement sont à l’origine de détériorations des performances aérodynamiques, de fatigues structurelles ou de nuisances sonores. La compréhension de ces phénomènes reste encore aujourd’hui l’un des enjeux majeurs de la recherche en aérodynamique. Le développement de systèmes permettant de contrôler l’écoulement et d’altérer ou de réduire les décollements apparaît comme une solution prometteuse en vue d’améliorer les performances aérodynamiques. On distingue les systèmes de contrôles passifs, simples d’utilisation mais incapables de s’adapter aux modifications de l’écoulement, des systèmes actifs qui disposent d’une grande adaptabilité mais nécessitent un apport extérieur d’énergie pour fonctionner. La stratégie du contrôle auto-adaptif s’apparente à un compromis entre ces deux méthodes. En s’inspirant de mécanismes présents dans la nature, elle permet d’associer amélioration des performances aérodynamiques, adaptabilité et autonomie. Ce travail de thèse porte sur l’étude expérimentale du contrôle du sillage turbulent d’un corps épais à l’aide d’actionneurs bio-inspirés avec un double objectif : i. déterminer les paramètres optimaux du dispositif de contrôle qui prend la forme d’un couple de volets flexibles, ii. Identifier les mécanismes physiques d’interactions entre l’actionnement et l’écoulement. Pour mener à bien cet objectif, de nombreux instruments de mesure complémentaires ont été mis en oeuvre. Une étude paramétrique a permis de démontrer l’efficacité du dispositif pour différentes configurations (fixes et auto-adaptatives) et d’identifier des configurations d’intérêt. La caractérisation de l’écoulement autour et dans le sillage du cylindre carré sans et avec contrôle a révélé un allongement de la longueur de recirculation à l’arrière du cylindre et la réduction de l’expansion du sillage. L’un des résultats majeurs de l’étude est que la réduction de traînée obtenue est principalement liée à une action du système sur l’anisotropie des fluctuations de l’écoulement et plus particulièrement sur l’entrainement du fluide dans le sillage de l’obstacle. / Flow separations around moving bodies lead to detrimental effects such as aerodynamic performances loss, structural fatigue and noises production. The understanding of these phenomena remains one of the most challenging issue of modern fluid dynamics. A promising solution to improve aerodynamic performances relies on the development of flow control devices able to prevent or mitigate the effects of separation. One can distinguish the passive flow control strategy, with easy to use devices but unable to adapt to the flow changes, from the active flow control strategy which benefits from a great adaptability but requires external power supply. Self-adaptive flow control appears to be a good compromise between those two strategies. Inspired from mechanisms at play in Nature, it combines good aerodynamic performances, self-adaptability and self-sustainability. This PhD thesis is dedicated to the experimental investigation of the turbulent flow over a bluff-body controlled by means of bio-inspired devices. The objective is two-folds : i. Design the control device which consists of a couple of compliant flaps, ii. Identify the physical mechanisms governing the interactions between the flow and the devices. A great number of complementary measurement techniques have been used in order to achieve these objectives. The efficiency of the devices for different configurations – locked and self-adaptive flaps - has been demonstrated through a parametric study. It has led to the identification of the main parameters involved in the control mechanism. The flow characterization around and in the wake of both uncontrolled and controlled cylinder revealed an increase in the length of the recirculation region and the reduction of the wake width. One of the major findings of this study is that the control essentially modifies the turbulent velocity field leading to a reduction of the lateral flow entrainment in the wake of the obstacle.

Orientador: Júlio Borges de Souza / Resumo: O transformador de estado sólido tem se apresentado como uma ferramenta indispensável na construção das novas redes elétricas inteligentes, uma vez que essa nova estrutura de rede altera o layout tradicional, viabilizando a conexão de fontes de energia descentralizadas. Contudo, essa conexão de sistemas de geração distribuída na rede originou a bidirecionalidade do fluxo de potência, resultando em um novo panorama para as atividades de operação e manutenção das redes para as distribuidoras de energia. A análise dos possíveis impactos técnicos gerados na rede de distribuição deve ser realizada, com o intuito de garantir um nível de qualidade energética dentro dos padrões estabelecidos pela Agência Nacional de Energia Elétrica – ANEEL. Dentre os impactos, destacam-se a elevação do nível de tensão e a alteração do fator de potência, ambos, produzidos pelo excesso de potência injetada na rede por este novo cenário de geração de energia. Nesse contexto, esta dissertação tem como principal objetivo analisar o comportamento de uma rede de distribuição genérica com penetração de geração distribuída e avaliar o perfil de tensão diante de diferentes níveis de inserção dessa geração na rede. As características de ajuste de tensão instantânea e capacidade de interação com sistemas de armazenamento que o transformador de estado sólido possui foram empregadas no auxílio da regulação dos níveis de tensão que se apresentaram fora dos padrões determinados pela resolução 794/2018 da ANEEL, qua... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The solid state transformer has been presented as an essential tool in the construction of new intelligent electric grids, since this new network structure changes the traditional layout, making possible the connection of decentralized energy sources. However, this connection of distributed generation systems in the network created the bidirectionality of the power flow, resulting in a new panorama for the power distributors concerning the networks activities of operation and maintenance. The analysis of the possible technical impacts generated in the distribution network should be carried out with the purpose of guaranteeing a level of energy quality within the standards established by the National Electric Energy Agency (ANEEL). Among the impacts, we highlight the elevation of the voltage level and the change in the power factor, both produced by the excess power injected into the grid by this new energy generation scenario. In this context, the main objective of this dissertation is to analyze the behavior of a generic distribution network with distributed generation penetration and to evaluate the voltage profile before different levels of insertion of this generation in the network. The solid state transformer has instantaneous voltage adjustment characteristics and interaction capacity with storage systems, which were used to aid in the regulation of voltage levels that were out of the standards determined by ANEEL resolution 794/2018, when a high level of distributed g... (Complete abstract click electronic access below) / Mestre

Submitted by Lucas Antonio Alves De Godoi (luksg@hotmail.com) on 2018-07-11T15:22:59Z No. of bitstreams: 1 Dissertação_Lucas _Godoi.pdf: 3300304 bytes, checksum: 429eb486ffbb167f9c7394e2d2e4b6f6 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-07-11T17:29:00Z (GMT) No. of bitstreams: 1 godoy_laa_me_ilha.pdf: 3300304 bytes, checksum: 429eb486ffbb167f9c7394e2d2e4b6f6 (MD5) / Made available in DSpace on 2018-07-11T17:29:00Z (GMT). No. of bitstreams: 1 godoy_laa_me_ilha.pdf: 3300304 bytes, checksum: 429eb486ffbb167f9c7394e2d2e4b6f6 (MD5) Previous issue date: 2018-04-17 / O transformador de estado sólido tem se apresentado como uma ferramenta indispensável na construção das novas redes elétricas inteligentes, uma vez que essa nova estrutura de rede altera o layout tradicional, viabilizando a conexão de fontes de energia descentralizadas. Contudo, essa conexão de sistemas de geração distribuída na rede originou a bidirecionalidade do fluxo de potência, resultando em um novo panorama para as atividades de operação e manutenção das redes para as distribuidoras de energia. A análise dos possíveis impactos técnicos gerados na rede de distribuição deve ser realizada, com o intuito de garantir um nível de qualidade energética dentro dos padrões estabelecidos pela Agência Nacional de Energia Elétrica – ANEEL. Dentre os impactos, destacam-se a elevação do nível de tensão e a alteração do fator de potência, ambos, produzidos pelo excesso de potência injetada na rede por este novo cenário de geração de energia. Nesse contexto, esta dissertação tem como principal objetivo analisar o comportamento de uma rede de distribuição genérica com penetração de geração distribuída e avaliar o perfil de tensão diante de diferentes níveis de inserção dessa geração na rede. As características de ajuste de tensão instantânea e capacidade de interação com sistemas de armazenamento que o transformador de estado sólido possui foram empregadas no auxílio da regulação dos níveis de tensão que se apresentaram fora dos padrões determinados pela resolução 794/2018 da ANEEL, quando um alto nível de geração distribuída foi inserido na rede. / The solid state transformer has been presented as an essential tool in the construction of new intelligent electric grids, since this new network structure changes the traditional layout, making possible the connection of decentralized energy sources. However, this connection of distributed generation systems in the network created the bidirectionality of the power flow, resulting in a new panorama for the power distributors concerning the networks activities of operation and maintenance. The analysis of the possible technical impacts generated in the distribution network should be carried out with the purpose of guaranteeing a level of energy quality within the standards established by the National Electric Energy Agency (ANEEL). Among the impacts, we highlight the elevation of the voltage level and the change in the power factor, both produced by the excess power injected into the grid by this new energy generation scenario. In this context, the main objective of this dissertation is to analyze the behavior of a generic distribution network with distributed generation penetration and to evaluate the voltage profile before different levels of insertion of this generation in the network. The solid state transformer has instantaneous voltage adjustment characteristics and interaction capacity with storage systems, which were used to aid in the regulation of voltage levels that were out of the standards determined by ANEEL resolution 794/2018, when a high level of distributed generation was inserted into the network.

L'objectif de ce travail est de fournir des modèles et outils pour simplifier la construction des systèmes distribués à base de composants sécurisés, ainsi que la gestion des propriétés de sécurité, en utilisant des outils de haut niveau d'abstraction pour la configuration et la reconfiguration dynamique. En plus des propriétés d'accessibilité et de communications sécurisées classiques, nous focalisons notre travail sur une propriété des systèmes répartis plus générale : la non-interférence. Cette propriété atteste qu'il ne doit pas y avoir de flux d'information entre des parties publiques et privées du système. Ce qui implique le suivi de l'acheminement de l'information entre les différentes composantes du système distribué. Notre objectif principal est donc de proposer un modèle, accompagné d'un ensemble d'outils, garantissant la propriété de la non-interférence à la construction du système, et ce à une plus grosse granularité : celle des composants. Ces outils permettent de (1) configurer les paramètres de sécurité des composants et des liaisons entre eux, (2) vérifier la propriété de non-interférence dans le code d'un composant et entre les différents composants du système et (3) générer automatiquement le code nécessaire pour appliquer ces propriétés de sécurité. D'autre part, nous proposons une architecture permettant de vérifier dynamiquement la propriété de non-interférence dans un système réparti. / The goal of this thesis is to provide models and tools to simplify secured component-based distributed systems' construction and the management of their security properties, by using high-level tools for dynamic configuration and reconfiguration. In addition to the classic properties of accessibility and secured communications, we focus on a more general security property of distributed systems : the non-interference. This property says that there mustn't be information flow between secret and public parts of the system ; which requires information flow control across the system. Our main objective is to propose a model and set of tools guarantying the non-interference property at compiletime, and at a bigger granularity : the components. These tools are (1) tools for configuring security parameters of components and binding between components, (2) a compiler checking the non-interference property, and (3) tools for automatic generation of code assuring these security properties. On the other hand, we present an architecture enabling a dynamic verification of the non-interference property in a distributed system.

Fluidos em uma descarga brilhante à pressão atmosférica usando uma barreira de dielétrico DBD atraiu o interesse das comunidades de termo-dinâmica, fluido-dinâmica, e comunidades de controle. Este trabalho investiga os efeitos de um atuador de plasma operando numa voltagem e frequência de 8 kV e 4.4 kHz sobre a curva do Cp de um cilindro de PVC em baixa velocidade de escoamento. O experimento foi repetido com o atuador em vários ângulos no cilindro. Os resultados mostram uma aceleração do escoamento junto com um atraso da separação. Esses efeitos são maiores quando o atuador é posicionado num ângulo mais próximo da região da separação. / Fluids in a dielectric barrier DBD glow discharge at atmospheric pressure attracted the interest of the communities of thermo and fluid dynamics as well as control. This dissertation investigates the effects of a plasma actuator operating at 8 kV and 4.4 kHz, on the Cp curve of a PVC cylinder in a low velocity airflow. The experiment was repeated with the actuator at various angles. The results show an acceleration of the flow accompanied with a delay of the flow separation. These effects were shown to be larger when the actuator was positioned at an angle closer to the region of separation.

A presente dissertação trata da implementação, em um equipamento de eletroforese capilar (CE) com detecção condutométrica sem contato (C4D), de um sistema de controle externo do fluxo eletrosmótico (EOF) via tensão radial externa (Vrad). Através do potencial externo, aplicado diretamente ao capilar, é possível ter o controle do fluxo eletrosmótico de CE, pois, de forma simplificada, esta prática acopla vetorialmente um potencial externo aplicado com o potencial através da solução tampão dentro do capilar. O emprego da técnica possibilitou o aumento de resolução de 2 aminoácidos - Leucina e Isoleucina, cujas mobilidades diferem apenas de 0,12 cm2.V-1.s-1 entre si, em ácido acético 500 mmol.L-1 com pH = 2,55. A estratégia empregada aqui foi a que denominamos de \"coluna capilar infinita\", na qual, com as sucessivas inversões na direção do EOF, conseguimos aprisionar, dentro da coluna capilar, espécies com mobilidade eletroforética menor que a mobilidade do EOF. A literatura descreve que a inversão do EOF se torna mais difícil com o aumento do pH. Foram realizados testes em eletrólitos contendo agentes inversores de fluxo como o CTAB, o CaCl2 e o BaCl2. Ambos os aditivos foram usados em concentrações muito baixas, nas quais foi mantida a direção normal do EOF, sendo que a utilizaçãode tais agentes teve a finalidade apenas de reduzir os grupos silanolatos em soluções de pH acima de 6,0. Tal estratégia proporcionou a reversão do EOF no sistema tampão MES/HIS, cujo pH estava em torno de 6,1. Por fim, a pesquisa gerou uma perspectiva interessante que é a possibilidade de se encontrar combinações de eletrólitos de corrida e surfactantes com o intuito de se estender a faixa de alcance do Vrad para valores altos de pH. / This work presents the implementation, in an equipment for capillary electrophoresis (CE) with contactless conductivity detection (C4D), of a system for external control of the electroosmotic flow (EOF) via external radial voltage (Vrad). Through external potential, directly applied to the capillary, the electroosmotic flow can be controlled, because this practice couples the applied external potential to the zeta potential through the buffer solution within the capillary. The use of the technique allowed the baseline resolution of two amino acids (Leucine and Isoleucine), whose mobilities differ only by 0,12 cm2.V-1.s-1, using acetic acid 500 mmol.L-1 at pH = 2,55 as the running electrolyte. The approach, called \"infinite capillary column\", consists in successive reversals in the direction of the EOF, trapping species within the capillary column with electrophoretic mobility smaller than the EOF mobility. Thus, the two amino acids were retained by a period of approximately 120 minutes in the capillary that was enough to promote the baseline resolution. Previous works describe that the reversion of the EOF becoming more difficult as pH increases. In order to achieve a more effective control of EOF at high pH values (limiting the technique to a narrow performance band), tests were carried out in electrolytes containing flow reversing agents such as CTAB, CaCI2 and BaCI2. These additives were used at very low concentrations, which kept the normal direction of EOF, and the use of such agents had only the purpuse of reducing the density of silanolate groups in solutions of pH above 6,0. This approach allowed the reversion of the EOF using MES/HIS buffer, which pH was 6,1. Finally, this research has generated an interesting perspective about the possibility of finding combinations of electrolytes and surfactants aiming the Vrad range´s extension at high pH values.

Ce travail de thèse, mené dans le cadre d’une convention CIFRE entre Snecma, le CERFACS et le LMFA, s’inscrit dans un contexte d’amélioration des performances et d’extension de la plage de fonctionnement des compresseurs de type axial équipant les turboréacteurs. L’une des principales difficultés rencontrée dans cette démarche concerne la maîtrise des écoulements dans la zone de jeu en tête des aubes rotors et qui peuvent entraîner une perte de stabilité du système (pompage et décollement tournant).Une solution technologique prometteuse pour améliorer la stabilité est le traitement de carter qui consiste en un dispositif passif complexe de fentes implantées au carter au droit des rotors. En vue d’en améliorer sa conception, les travaux de thèse visent plus particulièrement à approfondir la compréhension des mécanismes d’action grâce à une approche numérique CFD avec le code elsA développé par l’ONERA et le CERFACS, en modélisation stationnaire et instationnaire. Ces travaux s’articulent autour de trois axes principaux. Le premier a eu pour objectif de développer un outil numérique d’aide à la compréhension des mécanismes d’action des traitements de carter et de diagnostic de leur efficacité. Le principe de l’outil, qui est une extension du modèle initialement proposé par Shabbir et Adamczyk, repose sur une évaluation des contributions des termes des équations de Navier-Stokes stationnaires et instationnaires sur un volume de contrôle pris dans l’écoulement. Dans le cas pratique, cela revient à quantifier les efforts appliqués sur le fluide. Le second axe traite de l’analyse des mécanismes d’action des traitements de carter axisymétriques dans deux compresseurs axiaux : l’un subsonique à carter cylindrique (CREATE) et l’autre transsonique à carter conique (NASA Rotor 37). Les enseignements de cette étude indiquent que ce type de géométrie est marqué par son effet d’aspiration de fluide dans la veine. Ce mécanisme est d’autant plus amplifié par un phénomène d’interaction complexe des fentes avec l’écoulement de jeu et la proximité de l’intrados de l’aube adjacente. Cette partie s’est également attardé à la réponse des rainures à un phénomène instationnaire de type sillage de roue amont. Les résultats ont montré que les fentes amortissent les fluctuations de gradient de pression adverse. Le troisième axe porte sur l’analyse des mécanismes des traitements de carter non-axisymétriques à travers l’étude numérique d’un cas test transsonique à carter cylindrique (CBUUA). Le mécanisme d’action améliorant la stabilité de la machine tient en la capacité des fentes à limiter la migration dans la direction circonférentielle du vortex de jeu. Les résultats montrent que ce type de géométrie est caractérisé par son effet de réinjection d’air qui vient ré-énergétiser l’écoulement proche carter. / This thesis work, conducted as part of a CIFRE agreement between Snecma, CERFACS and LMFA, deals with the context of improving performance and extending the operating range of axial compressors fitted turbojets. One of the main difficulties in this approach is the flow control in the rotor tip region, which can cause the loss of the system stability (surge and rotating stall). A promising technology known to bring substantial stability is the casing treatment. This passive control device consists of slots of complex geometry within the rotor casing. In order to improve its design, the thesis aimed specifically at improving the understanding of their mechanisms through a numerical approach using the CFD code elsA developed by ONERA and CERFACS, with steady and unsteady approaches. This work focused on three main axes. The first concerns the development of a numerical tool to support the understanding of casing treatment mechanisms and the diagnosis of their efficiency. The principle of the tool, which is an extension of the model originally proposed by Shabbir and Adamczyk, is based on an assessment of the contributions of the terms of the steady and unsteady Navier-Stokes equations on a control volume taken in the flow. In practice, this permits to quantify the forces applied to the fluid. The second axis deals with the analysis of the flow mechanisms induced by axisymetric casing treatments in two axial compressors : one subsonic with a cylindrical casing (CREATE) and the other transonic with a conical casing (NASA Rotor 37). The findings of this study indicate that this type of geometry is characterized by its bleeding effect. This mechanism is further amplified by a complex phenomenon of interaction between grooves, tip leakage vortex and the proximity to the pressure side of the adjacent blade. This part has also dwelt on the groove’s response to unsteady upstream stator wakes. The results showed that the slots are able to damp fluctuations of adverse pressure gradient. The third area concerns the analysis of the flow mechanisms induced by non-axisymmetric casing treatment through the numerical study of a transonic compressor with cylindrical casing (CBUUA). The mechanism leading to an enhancement of the stability results in slots ability to limit the migration in the circumferential direction of the tip leakage vortex. The results show that this type of geometry is characterized by its effect of re-injection of fluid that comes re-energize the near casing flow.

Ce manuscrit présente les travaux de thèse réalisés dans le cadre d’une convention CIFRE entre Renault Trucks et le LMFA. Une stratégie de contrôle d’écoulement, associant un volet déflecteur et des actionneurs de type jets pulsés et synthétiques, est étudiée expérimentalement en vue de réduire la traînée aérodynamique de corps non profilés à culot droit. Une première approche consiste à étudier l’influence de cette stratégie sur une maquette bidimensionnelle. Des mesures de vitesse dans le sillage proche par TR-PIV et par anémométrie à fil chaud démontrent qu’une certaine gamme de fréquence d’actionnement permet à l’écoulement de recoller sur le volet et de diminuer les fluctuations de vitesse dans la zone de recirculation, ce qui engendre une augmentation de la pression au culot. Une analyse par moyenne de phase et la détermination de corrélations spatio-temporelles permettent d’identifier les perturbations induites par le contrôle conduisant à ces modifications de l’écoulement. Un système de jets synthétiques est ensuite intégré à une maquette simplifiée de véhicule poids lourd à l’échelle 1/8e, dont le sillage est représentatif des remorques réelles. Des gains en traînée significatifs sont obtenus et sont associés aux mêmes phénomènes aérodynamiques que pour la maquette bidimensionnelle. Enfin, une étude paramétrique montre la robustesse du contrôle aux caractéristiques de la couche limite incidente aux jets et à la longueur du volet déflecteur. / This document presents the research work realized in the scope of a PhD thesis with Renault Trucks and the LMFA. A flow control strategy, combining an inclined flap with pulsed or synthetic jets, is experimentally studied to reduce the aerodynamic drag of square-back bluff bodies. A first approach consists in studying the effect of this strategy on the flow behind a twodimensional model. The near-wake flow is characterized by the use of velocity measurements obtained by Time-Resolved Particles Image Velocimetry and hot-wire Anemometry. These measurements show that the increase in rear base pressure, obtained in a specific range of actuation frequencies, is associated with the reattachment of the flow on the flap and with a decrease in velocity fluctuations within the recirculation area. A phase average analysis and the determination of space-time correlations allow identifying the aerodynamic disturbances induced by the control system and leading to these modifications of the wake flow. A synthetic jet system is integrated to a 1 :8 scale simplified truck model, with a wake flow similar to this of real trailers. Significant drag reductions are obtained using active control and are associated with the same flow phenomena as these observed in the two-dimensional model study. Eventually, a parametric study is performed and shows the robustness of the flow control strategy to the characteristics of the boundary layer developing on the model roof and to the flap length.

L'enveloppe de vol des hélicoptères est limitée par le décrochage dynamique, que le contrôle d'écoulement permet de surmonter. Malgré de nombreuses études, aucun dispositif de contrôle ne s'est révélé utilisable sur un rotor. Conçu par l'ONERA, un Vortex Generator déployable (DVG) s'est révélé efficace pour limiter les effets du décrochage dynamique d'un profil OA209 en oscillation de tangage. Mais l'étude de cet actionneur est nécessaire avant son application. Le travail exposé dans le présent mémoire s'attache à reproduire par simulations numériques l'écoulement du décrochage dynamique contrôlé par DVG afin d'identifier les phénomènes physiques en jeu. Après une première partie bibliographique dédiée au contrôle de décrochage dynamique et aux Vortex Generators, une seconde partie a été consacrée à valider et étudier la simulation numérique du contrôle du décrochage statique. L'écoulement induit a pu être ainsi caractérisé par les interactions tourbillonnaires présentes du fait de l'épaisseur du DVG et qui réduisent l'efficacité du contrôle. Cette analyse a permis d'élaborer une modélisation préliminaire du DVG. Dans une troisième partie, la validation et l'étude de la simulation numérique du contrôle du décrochage dynamique a mis en évidence un effet de contrôle similaire au cas statique, et la décomposition en modes propres orthogonaux de l'écoulement contrôlé a montré une altération du mode lié au tourbillon de décrochage dynamique. Ce travail valide la simulation numérique mise en place, laisse entrevoir des perspectives d'amélioration du dispositif de contrôle et permet la simulation numérique ultérieure du contrôle de décrochage dynamique de voilure tournante. / The helicopter flight envelope is limited by dynamic stall, which can be reduced by flow control actuation. Numerous studies are dedicated to the alleviation of dynamic stall, however no actuator has ever been used on real rotor configuration. A new deployable Vortex Generator-type actuator called DVG has been designed by the ONERA and proved its efficiency over pitch-oscillating dynamic stall control of an OA209 airfoil. However, the control effect must be in-depth analyzed before further application. Therefore, the present works aims at reproducing the dynamic stall control through numerical simulations,in order to investigate the physics involved. After a first part dedicated to the literature review of dynamic stall control and Vortex Generators, a second part considered the validation and investigation of the static stall control. DVG-induced secondary flow has been characterized by its vortex interactions, which reduce the control efficiency because of the DVG thickness. This analysis made a preliminary modeling of the DVG possible. In a third part, validation and investigation of the dynamic stall control have been performed, and the actuation showed strong similarities with the static case. Eventually, Proper Orthogonal Decomposition of the flow brought evidence of Dynamic Stall Vortex mode distortion thanks to DVG presence. This work validates the numerical simulation methodology, lets hope possible improvement of the actuator design and allows further numerical simulations of dynamic stall control over real helicopter blades.