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The discharge through a river hydropower plant must be controlled such that the water level at a pre-specified point close to the facility is kept within given bounds. The controllers used today have a somewhat demanding tuning and often create too much amplified, unnatural discharge variations resulting in unsatisfactory control performance.This will affect both surrounding nature and imposing problems for river navigation. This thesis will present a new type of controller called Override Selector feedback Control that adds an estimator for the water levels and water flows in the up- and downriver for each hydropower plant on top of the old controller. The objective of the state feedback control is to keep the total variation of the water levels and the waterflows as small as possible. After the linear, discrete time model of the power plant cascade in a river derived from the Saint Venant equations have been developed, the new concept is evaluated. Both the water level sloshing and the amplification of the discharges compared to the structure used today is damped with the new control structure. Other advantages of the proposed controller is that it will be cost efficient to implement because of the add-on approach. This is seen as a very important factor while the actual benefit that can be made by improving the water level control is very limited and thereby also the will to make extensive control investments. The control structure will be easily implemented as the estimators only need the same input data as used today.

O gerenciamento integrado de recursos hídricos envolve partes com usos conflitantes entre si. Portanto o gerenciamento eficiente dos reservatórios é importante para atender múltiplos objetivos operacionais: abastecimento hídrico, navegação, geração hidroelétrica, requisitos ambientais e controle de cheias. Recentemente desenvolvimentos na previsão numérica climática, dados de radares meteorológicos e aquisição de dados hidrológicos e meteorológicos on-line resultaram em um crescente interesse em processamento de importação de dados. Implementando controle preditivo com horizonte de previsão de curto prazo, é possível prever condições de estresse ou de pico de vazão, que auxilia os tomadores de decisão a agir antecipadamente, assim minimizando os impactos negativos destes eventos. Para eventos de cheia, os operadores podem verter previamente água do reservatório alocando volume de reservação adicional para mitigar os danos de inundação nas margens à jusante do corpo d\'água. Neste cenário, para obter estimativas do escoamento a jusante referentes às mudanças de vertimento do reservatório, é necessário um modelo de escoamento robusto e rápido. Avaliou-se neste contexto cinco modelos diferentes quanto suas potencialidades de implementação em um modelo de controle preditivo para o reservatório de Três Marias, localizado na bacia do Alto São Francisco, Brasil. Estes modelos são: i) SOBEK que utiliza a equação hidrodinâmica de Saint-Venant; ii) SPRNT que utiliza a equação hidrodinâmica de Saint-Venant utilizando técnicas de aceleração para cálculo; iii) MGB-IPH (Modelo Hidrológico de Grandes Bacias - Instituto de Pesquisas Hidráulicas), modelo chuva-vazão semi-distribuído que utiliza o método de Muskingum-Cunge para determinar o escoamento nos canais de interesse; iv) um modelo de onda difusiva; e v) um modelo simplificado de propagação de ondas em reservatório, equivalente à onda cinemática. Os dois últimos modelos estão implementados no pacote de ferramentas do RTC-Tools, a ferramenta de cálculo de controle em tempo real. Em geral os resultados entre os modelos simplificados do RTC-Tools e o modelo mais sofisticado SOBEK são comparáveis, no entanto os dois métodos com abordagem hidráulica, SOBEK e o modelo difusivo do RTC-Tools, apresentam difusão numérica por causa da baixa resolução espacial. No modelo de propagação de vazão por reservatórios simples a adoção de advecção pura através de um retardamento temporal mostrou-se uma correção eficiente para a difusão numérica excessiva apesar da baixa resolução espacial. Do ponto de vista de controle preditivo, esta abordagem possui melhor \"custo-benefício\" entre robustez, eficiência computacional e precisão. / Integrated Water Resources Management involves parties with conflicting interests. Therefore an effective reservoir management is important to meet multiple operating objectives such as water supply, navigation, hydroelectricity generation, environmental obligations and flood protection. Recent upcomings in numerical weather forecast, radar data and online data acquisition resulted in an interest for data import processes. By implementing a predictive control approach over a short-term forecast horizon, it is possible to foresee stress conditions or peak flow events and support decision-makers to take actions before these events happen to minimize their negative impacts. In the case of flood events, this technique enables the operators to pre-release water from a reservoir for allocating additional storage before the flood event occurs in order to mitigate flood damage along downstream river reaches. In this scenario, a robust and fast routing model is required to obtain quick and reliable estimates of downstream flow conditions related to release changes of the reservoir. In this context, five different models are assessed concerning their implementation in a predictive control of the Três Marias reservoir located at the Upper River São Francisco in Brazil: i) a fully dynamic model using the software package SOBEK; ii)SPRNT a fully dynamic model using acceleration calculation techniques; iii) a semi-distributed rainfall-runoff model with Muskingum-Cunge routing for the flow reaches of interest, known as MGB-IPH (Modelo Hidrológico de Grandes Bacias - Instituto de Pesquisas Hidráulicas); iv) a diffusive wave model and v) Kinematic Wave equivalent simplified reservoir routing. The last two models are implemented in the RTC-Tool toolbox, a software for real-time control applications. In general, we find comparable results between the simplified models in RTC-Tools and the more sophisticated SOBEK model and a lower performance of the MGB model. However, both hydraulic modelling approaches, i.e. the SOBEK model as well as the diffusive wave model in RTC-Tools, suffer from too much numerical diffusion in case of course grids. In the reservoir routing approach, the introduction of pure advection by time lags offers an efficient solution for excessive numerical diffusion even on courser grids. From the predictive control point of view, this approach shows the best compromise in terms of robustness, computational efficiency and accuracy.

O gerenciamento integrado de recursos hídricos envolve partes com usos conflitantes entre si. Portanto o gerenciamento eficiente dos reservatórios é importante para atender múltiplos objetivos operacionais: abastecimento hídrico, navegação, geração hidroelétrica, requisitos ambientais e controle de cheias. Recentemente desenvolvimentos na previsão numérica climática, dados de radares meteorológicos e aquisição de dados hidrológicos e meteorológicos on-line resultaram em um crescente interesse em processamento de importação de dados. Implementando controle preditivo com horizonte de previsão de curto prazo, é possível prever condições de estresse ou de pico de vazão, que auxilia os tomadores de decisão a agir antecipadamente, assim minimizando os impactos negativos destes eventos. Para eventos de cheia, os operadores podem verter previamente água do reservatório alocando volume de reservação adicional para mitigar os danos de inundação nas margens à jusante do corpo d\'água. Neste cenário, para obter estimativas do escoamento a jusante referentes às mudanças de vertimento do reservatório, é necessário um modelo de escoamento robusto e rápido. Avaliou-se neste contexto cinco modelos diferentes quanto suas potencialidades de implementação em um modelo de controle preditivo para o reservatório de Três Marias, localizado na bacia do Alto São Francisco, Brasil. Estes modelos são: i) SOBEK que utiliza a equação hidrodinâmica de Saint-Venant; ii) SPRNT que utiliza a equação hidrodinâmica de Saint-Venant utilizando técnicas de aceleração para cálculo; iii) MGB-IPH (Modelo Hidrológico de Grandes Bacias - Instituto de Pesquisas Hidráulicas), modelo chuva-vazão semi-distribuído que utiliza o método de Muskingum-Cunge para determinar o escoamento nos canais de interesse; iv) um modelo de onda difusiva; e v) um modelo simplificado de propagação de ondas em reservatório, equivalente à onda cinemática. Os dois últimos modelos estão implementados no pacote de ferramentas do RTC-Tools, a ferramenta de cálculo de controle em tempo real. Em geral os resultados entre os modelos simplificados do RTC-Tools e o modelo mais sofisticado SOBEK são comparáveis, no entanto os dois métodos com abordagem hidráulica, SOBEK e o modelo difusivo do RTC-Tools, apresentam difusão numérica por causa da baixa resolução espacial. No modelo de propagação de vazão por reservatórios simples a adoção de advecção pura através de um retardamento temporal mostrou-se uma correção eficiente para a difusão numérica excessiva apesar da baixa resolução espacial. Do ponto de vista de controle preditivo, esta abordagem possui melhor \"custo-benefício\" entre robustez, eficiência computacional e precisão. / Integrated Water Resources Management involves parties with conflicting interests. Therefore an effective reservoir management is important to meet multiple operating objectives such as water supply, navigation, hydroelectricity generation, environmental obligations and flood protection. Recent upcomings in numerical weather forecast, radar data and online data acquisition resulted in an interest for data import processes. By implementing a predictive control approach over a short-term forecast horizon, it is possible to foresee stress conditions or peak flow events and support decision-makers to take actions before these events happen to minimize their negative impacts. In the case of flood events, this technique enables the operators to pre-release water from a reservoir for allocating additional storage before the flood event occurs in order to mitigate flood damage along downstream river reaches. In this scenario, a robust and fast routing model is required to obtain quick and reliable estimates of downstream flow conditions related to release changes of the reservoir. In this context, five different models are assessed concerning their implementation in a predictive control of the Três Marias reservoir located at the Upper River São Francisco in Brazil: i) a fully dynamic model using the software package SOBEK; ii)SPRNT a fully dynamic model using acceleration calculation techniques; iii) a semi-distributed rainfall-runoff model with Muskingum-Cunge routing for the flow reaches of interest, known as MGB-IPH (Modelo Hidrológico de Grandes Bacias - Instituto de Pesquisas Hidráulicas); iv) a diffusive wave model and v) Kinematic Wave equivalent simplified reservoir routing. The last two models are implemented in the RTC-Tool toolbox, a software for real-time control applications. In general, we find comparable results between the simplified models in RTC-Tools and the more sophisticated SOBEK model and a lower performance of the MGB model. However, both hydraulic modelling approaches, i.e. the SOBEK model as well as the diffusive wave model in RTC-Tools, suffer from too much numerical diffusion in case of course grids. In the reservoir routing approach, the introduction of pure advection by time lags offers an efficient solution for excessive numerical diffusion even on courser grids. From the predictive control point of view, this approach shows the best compromise in terms of robustness, computational efficiency and accuracy.

L'hydroélectricité est la première des énergies renouvelables électriques. Sa production repose en partie sur des centrales au fil de l'eau dont les capacités de modulation sont encore faiblement exploitées. Les capacités d'ajustement des centrales hydrauliques sont d'autant plus essentielles aujourd'hui que la pénétration d'énergies intermittentes dans un mix énergétique décarboné est indispensable.Dans cette thèse, nous nous intéressons aux centrales au fil de l'eau turbinant le débit de cours d'eau aux marnages limités. Les enjeux de sûreté, notamment liés au multi-usage de l'eau, ainsi que la perspective de moduler les débits turbinés nous ont amenés à considérer le problème de la modélisation des écoulements dans les canaux reliant les centrales au fil de l'eau. Les équations de Saint-Venant sont les plus pertinentes pour ce type de modélisation. Nous avons proposé plusieurs approches à partir de ces dernières pour caractériser analytiquement la dynamique de l'écoulement à des variations de débits turbinés. Nous avons considéré la dynamique du système autour d'un régime fluvial stationnaire non-uniforme caractéristique des configurations hydroélectriques. La première approche est basée sur une approximation basses fréquences. La seconde approche est basée sur une méthode de réduction de modèle avec une paramétrisation selon le débit support. Une troisième approche est proposée en considérant explicitement la recherche d'une solution approximée des équations de Saint-Venant linéarisées autour d'une configuration hydroélectrique. Un critère spatio-fréquentiel est alors introduit, l'existence d'un biais en basses fréquences nous conduit à proposer un modèle d'ordre réduit dont la dynamique basses fréquences est imposée selon les résultats de la première approche. La solution exprimée sous forme de fonctions de transfert, comme pour les deux précédentes approches, met en évidence explicitement la présence de modes de résonance/anti-résonance. Finalement, nous illustrons les résultats vis à vis de simulations non-linéaires et de données réelles et proposons une régulation de niveau basée sur cette dernière approche. / New challenges arise from energy transition toward a more sustainable energy mix. Hydropower is already the main source of renewable electricity. In order to integrate a massive increase in generation of renewable intermitent energies, improving the flexibility of run-of-the-river hydropower plants becomes essential. In this thesis, we focus on run-of-the river power plants facing water level constraints. Safety issues, partly due to the multiple uses of water, and the opportunity to modulate turbined flow rates have led us to adress the problem of flow modelisation in open channels that connect run-of-the rivers facilities with each others. An accurate model is provided by the Saint-Venant equations. From these latters, we have proposed different approaches to characterize analytically the flow dynamics in response to turbined flow variations. The system dynamics have been considered around a subcritical stationary non-uniform regime typical of hydroelectric configuration. The first approach is based on a low frequency approximation. The second approach is based on a parametric model reduction technique. By seeking explicitly an approximate solution to the linearized Saint-Venant equations around an hydroelectric configuration, we have proposed a third approach. A space-frequency criterion is introduced, which shows a bias in low frequency. Results of the first approach are then used to propose a reduced order model asymptotically exact in low frequency. As for the two other approaches, the solution takes the shape of parametric transfer functions. Resonance/anti-resonance modes explicitly appear. Finally, comparisons with non-linear simulations taking into account actual real data are discussed and a water level controller is developed based on the last approach.

Les inondations représentent le premier danger naturel sur chaque continent, avec des préoccupations particulières centrées sur les inondations urbaines pour l'urbanisation sans précédent, qui augmente la vulnérabilité des sociétés humaines aux inondations. Pour les difficultés d'accès aux données en temps réel, la méthode numérique semble être une approche puissante pour la prévision des inondations et l'atténuation des dommages. Dans cette thèse, un nouveau logiciel Flood1D2D pour la modélisation des crues urbaines a été proposé en utilisant le maillage de couplage 1D2D, avec 1D dans la rue et 2D appliqué au carrefour. Le logiciel est conçu sur la base de l'installation située dans ICube Strasbourg et validée à l'aide de cas de tests synthétiques. La nouveauté du modèle est de rendre compte de l'effet de recirculation en utilisant la fonction de porosité, et de reproduire la convexité dans les profils de profondeur le long de la rue en aval de chaque carrefour où une zone de recirculation apparaît. Une analyse de sensibilité basée sur la variance est également réalisée pour les modèles classiques d'eau peu profonde 1D et 2D pour l'étalonnage de modèles et la collecte de données. / Flooding represents the first natural hazard on each continent, with special concerns are focused on urban flooding for the unprecedented urbanization, which increases the vulnerability of human societies to floods. For the accessing difficulties of real-time data, numerical method seems to be a powerful approach for flood forecasting and damage mitigation. In this thesis, a new software Flood1D2D for urban flood modeling has been proposed using 1D2D coupling mesh, with 1D on the street and 2D applied on the crossroad. The software is designed based on the rig located in ICube Strasbourg and validated using synthetic test cases. The novelty of the model is to account for the recirculation effect using porosity function, and it can reproduce the convexity in water depth profiles along the street downstream each crossroad where a recirculation zone appears, which can't be accounted using roughness only. Variance based sensitivity analysis is also performed for classical 1D and 2D shallow water models for model calibration and data collections.

Dans ce manuscrit, nous parlons des matériaux composites à matrice céramiques (CMCs) qui sont envisagés pour intégrer les chambres de combustion de futurs moteurs aéronautiques civils. Pour faire face des conditions extrêmes, ces matériaux possèdent la particularité de s’auto-protéger vis-à-vis de l’oxydation par la formation d’un oxyde passivant qui limite la diffusion des espèces oxydantes au sein des fissures matricielles. Nous modélisons l’écoulement d’un oxyde dans une fissure par l’équation de Navier-Stokes, puis les mettons sous forme non dimensionnelles, et les dérivations de deux types de modèles sont intéressantes : les modèles de Saint-Venant et les modèles de lubrification. Ensuit nous nous engageons à chercher l’existence de solution faible de l’approximation de lubrification d’ordre 4 obtenue précédent dans le cas uni-dimensionnel. Enfin nous précisons la limite entre les équations de Saint-Venant et l’équation de lubrification. / In this work, we are interested in the ceramic matrix composite materials(CMCs) who will be used to integrate the combustion chambers of future civil aeronautical engines. To face extreme conditions, these materials possess the peculiarity to auto-protect itself towards the oxidation by the formation of an oxide passivate which limits the distribution of the oxidizing species within the matrix cracks. We model the flow of an oxide in a crack by the Navier-Stokes equation, then put them under an asymptotic analysis in order to get two types of asymptotic models : models of Saint-Venant (Shallow water model) and lubrication models. Next we are interested in looking for the existence of weak solution to the one-dimensional approximated lubrication equation of order 4 obtained before. Finally we talk about the limit between the Saint-Venant equations and the lubrication equation.

Cette thèse contribue à répondre au problème de la gestion optimale des ressources en eau dans les réseaux de navigation intérieure du point de vue de la théorie du contrôle. Les objectifs principales à atteindre consistent à garantir la navigabilité des réseaux de voies navigables, veiller à la réduction des coûts opérationnels et à la longue durée de vie des équipements. Lors de la conception de lois de contrôle, les caractéristiques des réseaux doivent être prises en compte, à savoir leurs dynamiques complexes, des retards variables et l’absence de pente. Afin de réaliser la gestion optimale, le contrôle efficace des structures hydrauliques doit être assuré. A cette fin, une approche de modélisation orientée contrôle est dérivée. Cependant, la formulation obtenue appartient à la classe des systèmes de descripteurs retardés, pour lesquels la commande prédictive MPC et l’estimation d’état sur horizon glissant MHE peuvent être facilement adaptés à cette formulation, tout en permettant de gérer les contraintes physiques et opérationnelles de manière naturelle. En raison de leur grande dimensionnalité, une mise en œuvre centralisée n’est souvent ni possible ni souhaitable. Compte tenu du fait que les réseaux de navigation intérieure sont des systèmes fortement couplés, une approche distribuée est proposée, incluant un protocole de communication entre agents. Malgré l’optimalité des solutions, toute erreur peut entraîner une gestion inefficace du système. Par conséquent, les dernières contributions de la thèse concernent la conception de stratégies de supervision permettant de détecter et d’isoler les pannes des équipements. Toutes les approches présentées sont appliquées à une étude de cas réaliste basée sur le réseau de voies navigables du nord e la France afin de valider leur efficacité. / This thesis addresses the problem of optimal management of water resources in inland navigation networks from a control theory perspective. The main objectives to be attained consist in guaranteeing the navigability condition of the network, minimizing the operational cost and ensuring a long lifespan of the equipment. However, their complex dynamics, large time delays and negligible bottom slopes complicate their management. In order to achieve the optimal management, the efficient control of the hydraulic structures must be ensured. To this end, a control-oriented modeling approach is derived. The resulting formulation belongs to the class of delayed desciptor systems, for which model predictive control and moving horizon estimation can be easily adapted, as well as being able to deal with physical and operational constraints in a natural manner. However, a centralized implementation is often neither possible nor desirable. As these networks are strongly coupled systems, a distributed approach is followed, featuring a communication protocol among agents. Despite the optimality of the solutions, any malfunction can lead to an inefficient system management. Therefore, the last part of the thesis regards the design of supervisory strategies that allow to detect and isolate faults. All the presented approaches are applied to a realistic case study based on the inland navigation network in the north of France to validate their effectiveness.