<p>Severe floods caused by heavy autumn rains in year 2000 raised the question whether measures to reduce the damage from high water levels, in the area surrounding lake Glafsfjorden and along the river Byälven down to lake Vänern, are possible. One option is to reduce flow resistance along the river and thereby lower the maximum water level a given inflow would cause. Good knowledge of hydraulic and hydrological conditions is necessary in order to estimate the effect of such flow-reducing measures. In order to quantify such effect a 1-dimensional hydraulic flow model has been set up for the river Byälven using the software package MIKE 11. The model is more detailed, especially concerning topography and bathymetry, than earlier models used for studies of the river. Boundary conditions consist of measured inflows, the level of the lake Vänern and runoff calculated using the HBV-model. The model was calibrated for two different floods and a good fit to measured water levels was obtained for both these periods. Using the calibrated model critical sections, causing much flow resistance during high floods, were identified. With that knowledge different measures to reduce high water levels was adopted to the model both individually and combined with each other and the model was run with boundary conditions mainly from the flood in year 2000. The most radical measures simulated resulted in a lowering of the maximum water in the two largest reservoirs Glafsfjorden and Harefjorden with 78 and 97 cm respectively. A more modest combination of measures gave water levels 48 and 84 cm lower than a model run without changes. Some combinations of relatively small measures lowered the maximum water level by a few decimeters. The simulation results give good guidance to further investigations and decisions of actual changes. The model constitutes a useful tool when making flood maps of the area and if water level forecasts would be needed during future floods.</p> / <p>Allvarliga översvämningar i samband med höstregn år 2000 väckte frågan om det går att vidta åtgärder för att minska skadorna vid höga flöden i området runt Glafsfjorden och längs Byälvens sträckning ner till Vänern. Ett alternativ är att med åtgärder längs älven underlätta vattnets utflöde och på så sätt minska den högsta vattennivå ett givet flöde orsakar. God kunskap om hydrauliska och hydrologiska förhållanden behövs för att bedöma nyttan av olika åtgärdsalternativ. För att kunna avgöra effekterna av olika åtgärdsalternativ har en 1-dimensionell strömningsmodell satts upp för Byälven i programverktyget MIKE 11. Modellen är mer detaljerad, framförallt beträffande höjdinformationen, än tidigare modeller som använts för studier av Byälven varit. Randvillkor till modellen utgörs av registrerade inflöden, Vänerns vattenstånd och avrinning modellerad med HBV-modellen. Modellen har kalibrerats för två översvämningsperioder och god anpassning uppnåddes för de vattenstånd som dessa situationer representerar och med dess hjälp har sedan älven studerats och områden som bromsar flödet har kunnat identifieras. Med kunskap om vilka områden som begränsar flödet mest har ett antal olika åtgärder simulerats i modellen, både var för sig och kombinerade med varandra. Randvillkoren för översvämningen år 2000 behölls och förändringarna lades in i modellen. De extremaste åtgärderna som simulerats resulterade i minskningar av de högsta vattennivåerna i de två största vattenmagasinen Glafsfjorden och Harefjorden med 78 respektive 97 cm. Mer realistiska åtgärdspaket gav minskningar med i storleksordningen 48 respektive 84 cm och även relativt små ingrepp gav minskningar på några decimeter. Simuleringsresultaten ger god vägledning för vidare undersökningar av och beslut om konkreta åtgärder i Byälven. Dessutom utgör modellen ett bra verktyg för att ta fram översvämningskartor och för att prognostisera vattennivåer vid nya översvämningssituationer.</p>

This thesis explains the model-based design of a fork control system in a turret head operated Very Narrow Aisle forklift in order to evaluate and push the limits of the current hardware architecture. The turret head movement consists of two separate motions, traversing and rotation, which both are hydraulically actuated. The plant is thoroughly modeled in the Mathworks softwares Simulink/Simscape to assist in the design of the control system. The control system is designed in Simulink/Stateflow and code-generated to be evaluated in the actual forklift. Optimal control theory is used to generate a minimum-jerk trajectory for auto-rotation, that is simultaneous traversing and rotation with the load kept in centre. The new control system is able to control the system within the positioning requirements of +/- 10 mm and +/- 9 mrad for traversing and rotation, respectively. It also shows good overall performance in terms of robustness since it has been tested and validated with different loads and on different versions of the forklift. However, the study also shows that the non-linearities of the system, especially in the hydraulic proportional valves, causes problems in a closed-loop control system. The work serves as a proof of concept for model-based development at the company since the development time of the new control system was significantly lower than for the original control system.

Les développements d'algues benthiques dans les canaux de transport d'eau induisent d'importantes contraintes pour la gestion des canaux de distri bution d'eau. Les nuisances physiques et chimiques associées à ces développements nécessitent des stratégies de gestion alternatives. La thèse étudie des méthodes pour la gestion de ces populations algale basées sur le contrôle hydraulique du système: les chasses hydrauliques. Ces opérations consistent à détacher une partie de la biomasse algale fixée en augmentant les contraintes de cisaillement exercées par le courant sur ces algues fixées au substrat. Leur remise en suspension, entraînant un pic de turbidité, doit également être maîtrisée. L'approche proposée vise à caractériser et modéliser les processus de développement, de détachement et de transport des algues lors de ces chasses hydrauliques. Des suivis expérimentaux de la croissance sont réalisés en mésocosme (à l'échelle de canaux réduits). Les suivis de biomasse permettent de caler un modèle de croissance de la couverture algale intégrant l'effet de l'hydrodynamique et de la s ensibilité des algues aux perturbations hydrodynamiques. Des stratégies de chasses sont ensuite expérimentées sur deux canaux de distribution d'eau en zone méditérannéenne. Un modèle de la dynamique des algues fixées et en dérive en réponse à une chasse hydraulique est ensuite élaboré sur la base de ces expérimentations, et calé sur les nuages de turbidité observés. Finalement, un cadre méthodologique basé sur un modèle linéaire est proposé pour des applications à la gestion en temps réel d'une variable de qualité : la turbidité. Deux approches de contrôle sont présentées : la commande en boucle ouverte et la commande adaptative qui permet de recaler les paramètres inconnus comme la biomasse initiale. / Algae developments in open-channel networks induce strong constraints for the network management. The physical and chemical nuisances linked to these developments require alternative management strategies. The thesis proposes an original method for these algae management based on the hydraulic control of the system using flushing-flows. These flushes consist in detaching a part of the fixed algae by increasing the hydraulic shear stress exerted on the biomass fixed on the substratum. The re-suspension of algae in the water column induces a turbidity peak which also has to be controlled. The proposed approach aims at characterizing and modelling the processes of algae development, detachment and transport during the flushes. Experimental monitoring of the growth phase is conducted in experimental flumes. The biomass samples are used to calibrate a model of algal growth which integrates the hydrodynamic effect and the algae sensitivity in the Med iterranean region. A model of the fixed and drift algae dynamics in response to a flush is then developed and calibrated on the observerd turbidity plumes. Finally, a control framework based on a linear model is proposed for the turbidity control during a flush. An open-loop control is first developed, then an adaptative feedback controller is tested to estimate unknown parameters such as initial biomass.

Les sels fondus ont récemment été proposés comme milieux caloporteurs à haute température. Dans l'industrie nucléaire, le concept de réacteur à sels fondus (MSR en anglais) est le seul concept de quatrième génération qui propose l'utilisation d'un sel fondu liquide comme combustible nucléaire. Cette innovation présente des aspects positifs pour la conception et la sûreté nucléaire, mais impose de nouveaux défis. Le réacteur rapide à sels fondus (MSFR en anglais) est un concept qui est actuellement étudié dans le projet européen H2020 SAMOFAR, incluant le développement et la validation expérimentale (dans la plateforme expérimentale SWATH) de modèles plus performants pour les sels fondus : tel est l'objectif de ce travail de thèse. En outre les modèles développés peuvent s'appliquer à d'autres MSRs et à d'autres applications énergétiques utilisant des sels fondus comme milieux caloporteurs.La thèse suivante est divisée en trois parties :Premièrement, le développement de modèles pour décrire de façon réaliste certains des phénomènes thermiques microscopiques et macroscopiques associés à l’utilisation de sels liquides fondus comme milieux caloporteurs. Cette partie comprend l’utilisation et le développement de nouveaux modèles neutroniques pour étudier la production d'énergie nucléaire, ainsi que la modélisation des phénomènes turbulents dans les sels fondus, l’étude de l’interaction du rayonnement thermique et la turbulence dans les sels fondus. Enfin, cette partie traite également du développement d’une approche multi-échelle pour l'étude précise de la solidification/fusion dans les sels.Deuxièmement, la conception et la mise en œuvre d’expériences dédiées à la validation de ces modèles. Deux expériences clés ont été conçues au cours de cette thèse et ont été implémentées dans la plate-forme SWATH. L'objectif de ces expériences est d'étudier le comportement de différents modèles de turbulence et de tester les modèles de solidification développés dans les sels fondus.Troisièmement, les modèles développés ont été couplés dans une plateforme multi-physique pour l'étude précise du transitoire drainant du MSFR. / Molten salts have been recently proposed as high-temperature heat carrier media for energy applications. In the nuclear industry, the Molten Salt Reactors (MSRs) are the only fourth generation concept proposing the usage of a liquid nuclear fuel. This innovative aspect allows proposing improved safety and design features, but it leads to novel challenges. In particular, the Molten Salt Fast Reactor (MSFR) is a MSR concept that is currently being studied in the H2020 European project SAMOFAR. Among the project activities, there are the development of more performant molten salts models and their experimental validation through the SWATH platform. This is the objective of the present thesis. However, the models developed are appropriate for other MSRs and other energy applications using molten salts as heat carrier media.The following thesis is divided into three parts.The first part is dedicated to the development of models for describing realistically some of the microscopic and macroscopic thermal phenomena associated with the usage of liquid molten salts as heat carrier media. This part includes the development and implementation of neutronic models to study nuclear power production in the MSFR, the study of turbulence and turbulence-radiation interaction in molten salt flows and the development of a multiscale approach to model the solidification/melting phenomena in salts.The second part is devoted to the design and implementation of dedicated experiments for validating these models. Two key experiments are addressed: an experiment to study the behavior of different turbulence models after a boundary layer detachment and one to test the multiscale solidification models developed for molten salts.The third part is committed to the coupling of the models developed into a multiphysics platform for the precise study of the draining transient of the MSFR.

L'érosion de contact est un type d'érosion interne qui se développe à l'interface entre deux couches de matériaux de granulométries différentes. Les particules d'un sol fin (sable, limon, argile…) sont détachées par l'écoulement et entraînées à travers les pores du sol grossier au contact (gravier…). Bien que l'on suspecte sa présence dans de nombreux ouvrages, ce processus d'érosion a été peu étudié jusqu'à présent. Aussi ce travail de thèse s'est attaché à mieux le comprendre pour parvenir à le modéliser. A l'échelle du pore, l'écoulement à l'interface entre deux milieux poreux a été caractérisé, grâce à un dispositif expérimental développé au Cemagref d'Aix-en-Provence qui combine fluorescence induite par laser, méthode PIV et milieu iso-indice. L'importance de la variabilité des sollicitations hydrauliques a ainsi été soulignée. A l'échelle de l'échantillon, des essais sur sols réels et sols reconstitués ont été menés au LTHE, afin d'identifier les phénomènes en jeu. Ont également été obtenues sur ce dispositif des mesures du taux d'érosion en fonction de l'intensité de l'écoulement, pour différents types de sols fins et de sols grossiers. Une modélisation stochastique de ces essais a ensuite été proposée. Enfin, des essais à grande échelle ont été conduits au laboratoire de la Compagnie Nationale du Rhône pour étudier l'éventuelle influence d'effets d'échelle ainsi que les conséquences de cette érosion de contact sur le comportement global et l'intégrité d'un ouvrage. Il a ainsi été mis en évidence la possibilité qu'une érosion de conduit soit initiée par érosion de contact. Cette thèse a été réalisée dans le cadre du projet ERINOH (ERosion INterne dans les Ouvrages Hydrauliques), en convention CIFRE avec le Centre d'Ingénierie Hydraulique d'EDF. / Contact erosion is a type of internal erosion which occurs at the interface between two soil layers of different particle sizes. Particles from the fine soil (sand, silt, clay…) are pulled and driven by the flow through the pores of the surrounding coarse soil (gravel ...). Although its presence is suspected in many earthfill embankments, this process has been little studied so far. The aim of this thesis was to better understand and, possibly, to model contact erosion. At pore scale, the flow at the interface between two porous media was characterized thanks to an experimental device, developed in Cemagref, combining Planar Laser Induced Fluorescence, PIV method and Refractive Index Matching. The spatial variability of flow shear stress has been emphasized. At sample scale, several tests on real and reconstituted soils were carried out in LTHE, in order to identify the phenomena involved in contact erosion. Erosion rates as a function of flow magnitude have also been measured for different types of fine and coarse soils. Then, a stochastic model was proposed to account for these experiments. Finally, large scale tests were conducted in the laboratory of Compagnie National du Rhône, to study the influence of scale effects as well as the consequences of contact erosion on global behavior and integrity of the embankment structure. The possibility of piping initiation by contact erosion was underlined. This thesis is part of the project ERINOH project and was funded by EDF-CIH.

A modelagem unidimensional tem sido adotada desde os anos 1980, com sucesso nas práticas de engenharia, para a caracterização do regime de transporte de sedimentos de longo termo. É também uma importante ferramenta para o entendimento da dinâmica sedimentar de bacias e gestão de sedimentos em reservatórios. Esta pesquisa teve como objetivo aplicar a modelagem unidimensional de transporte de sedimentos na bacia do reservatório Taiaçupeba, São Paulo, Brasil, a partir do sistema computacional HEC-RAS, orientada à estimativa das descargas sólidas afluentes ao reservatório. O período de coleta de dados coincidiu com a estiagem de 2013-2015 na Região Sudeste, o que contribuiu com a análise crítica do método e dos resultados, cuja discussão ressalta o uso da modelagem unidimensional como instrumento eficaz de validação das curvas de sedimento para caracterização do regime de transporte. As funções de capacidade de transporte de Laursen-Copeland e Toffaleti mostraram-se aplicáveis a esse sistema fluvial, bem como os métodos de encouraçamento de fundo de Hirano e Thomas-Copeland. Os coeficientes de Manning ajustados foram considerados preliminares e dados de campo adicionais são encorajados para refinar seu ajuste e incorporar maior acurácia na estimativa do perfil da linha d\'água em trabalhos futuros. Além disso, são apresentadas recomendações metodológicas ao monitoramento fluvissedimentométrico que contribuem com a sistematização das técnicas e tecnologias disponíveis à pesquisa hidrossedimentológica. / One-dimensional modeling has been successfully adopted since the 1980s in engineering practices to assess long-term sediment transport regimes. It is also an important tool for the understanding of sediment dynamics in watersheds and sediment management in reservoirs. The objective of this research was to apply the one-dimensional sediment transport modeling in the Taiacupeba reservoir basin, located in Sao Paulo, Brazil, implemented on HEC-RAS, aiming to estimate longterm loads into the reservoir. The data collection period coincided with the drought of 2013-2015 in Southeastern Brazil, which contributed to the critical analysis of the method and results, whose discussion highlights the use of one-dimensional modeling as an effective instrument for validating sediment curves. The transport capacity functions of Laursen-Copeland and Toffaleti have been shown to be applicable to this river system, as well as the bed sorting and armoring methods of Hirano and Thomas-Copeland. The Manning coefficients were considered preliminary and additional field data are encouraged to enhance its adjustment and incorporate greater accuracy in estimating the water surface profile in future work. Besides, methodological recommendations for sediment monitoring are presented, contributing to the systematization of available techniques and technologies applied to sediment research.

Desenvolve-se um método para estimar os parâmetros de uma rede hidráulica a partir de dados observados de cargas hidráulicas transientes. Os parâmetros físicos da rede como fatores de atrito, rugosidades absolutas, diâmetros e a identificação e quantificação de vazamentos são as grandezas desconhecidas. O problema transiente inverso é resolvido utilizando uma abordagem indireta que compara os dados disponíveis de carga hidráulica transiente observados com os calculados através de um método matemático. O Método Transiente Inverso (MTI) com um Algoritmo Genético (AG) emprega o Método das Características (MOC) na solução das equações do movimento para escoamento transiente em redes de tubos. As condições de regime permanente são desconhecidas. Para avaliar a confiabilidade do MTI-AG desenvolvido aqui, uma rede-exemplo é usada para os vários problemas de calibração propostos. O comportamento transiente é imposto por duas manobras distintas de uma válvula de controle localizada em um dos nós da rede. Analisam-se, ainda, o desempenho do método proposto mediante a variabilidade do tamanho do registro transiente e de possíveis erros de leitura nas cargas hidráulicas. Ensaios numéricos realizados mostram que o método é viável e aplicável à solução de problema inverso em redes hidráulicas, sobretudo recorrendo-se a poucos dados observados e ao desconhecimento das condições iniciais de estado permanente. Nos diversos problemas de identificação, as informações transientes obtidas da manobra mais brusca produziu estimações mais eficientes. / A method for estimation of parameters of existing hydraulic networks on the basis of observed transients pressures. Such parameters include pipe friction factors or absolute roughness, their diameters and the leakage locations and discharges. The inverse transient problem in terms of unknown parameters is solved through an indirect calibration procedure, which compares the calculated and observed hydraulic heads. The search method for optimal parameters employs the Method of Characteristics for the solution equations of transient motions in pipes and Genetic Algorithms. The initial conditions in the state of equilibrium are supposed unknown and the observed transient behavior of the network is in response to a valve maneuver composed of partial closure and reestablishment of flow in a pipe. In order to validate the transient calibration method, an example network is used to test various proposed calibration problems. The results show that the proposed method can be used with confidence for determination of various kinds of parameters. The transient inverse method is capable of network calibration using transient data collected at few locations in response to a quick valve maneuver.

Os projetos de redes hidráulicas dimensionam a capacidade de vazão e pressão para atender a uma demanda e prever a resistência necessária para garantir a estabilidade da instalação. Os esforços solicitantes não deverão ultrapassar as resistências estruturais, mantendo-se um coeficiente de segurança que garanta a estabilidade, mesmo nos casos de falhas operacionais. Deve-se proceder à simulação hidráulica tanto para o regime permanente quanto para o regime transitório. Na fase operacional haverão situações transitórias ocasionadas por manobras intencionais ou falhas não previstas que provocarão mudanças do regime permanente para o regime transitório, cuja variação de carga é diretamente proporcional à velocidade de propagação da onda ou celeridade e, dependendo da intensidade do transitório hidráulico, haverá a necessidade de instalar dispositivos de proteção de redes. A concepção dos dispositivos de proteção baseia-se na dissipação do fenômeno transitório por meios de descargas, amortecimento em câmaras de ar comprimido e por reservatórios intermediários que absorvem e suprem os picos de pressão e vazão no início da perturbação, de tal forma que a onda de pressão seja controlada. A celeridade, por sua vez, é função das características do meio fluido, do material da tubulação e da geometria. Ao provocar uma mudança na compressibilidade do meio fluido, tem-se redução no coeficiente de compressibilidade volumétrico da mistura fluida que vai ocasionar uma redução na velocidade de propagação da onda ou celeridade, amortecendo o impacto da variação de carga para níveis que possam ser absorvidos pela instalação. Esta dissertação aborda um dispositivo de redução da velocidade de propagação ou celeridade que pode ser usado como proteção de redes hidráulicas ou atenuador de celeridade, que junto com outros dispositivos e associados em série, distribuídos ao longo da tubulação, podem absorver os excessos de pressão e vazão gerados pelos transitórios e manter os esforços solicitantes inferiores à resistência oferecida pela instalação. / The projects of hydraulic networks define the capacity of outflow and pressure to meet a demand and to achieve the necessary resistance to guarantee the installation stability. The applied loading must not exceed structural resistance, there remaining a safety coefficient which guarantees the stability even in case of operational failure. The hydraulic simulation must be performed both for permanent and transitory regime. In the operational phase, there will be transitory situations caused by intentional maneuvers or unpredicted failures which will cause changes from permanent to transitory regime, with changes in load directly proportional to the propagation speed of the wave or celerity and, depending on the intensity of the hydraulic transient, it will be necessary to provide devices for the network protection. The conception of protection devices is based on the transient phenomena dissipation by means of discharges, shock absorption in air compressed chambers and though intermediate reservoirs, which absorb and supply the outflow and pressure peaks in the beginning of the disturbance. This dissertation approaches a device so that the pressure wave is controlled. The celerity, in its turn, is a function of the fluid characteristics, the network material and geometry. Provoking a change in the mean fluid compressibility there is a reduction in the volumetric compressibility coefficient and also in the specific mass of the mixture, which will cause a reduction in the speed of propagation of the wave or celerity, cushioning the impact of the pressure head variation to a level that can be absorbed by the installation. Therefore, the reduction in the speed of propagation or celerity canbe used is as a protection device for hydraulic nets, or celerity attenuation, which together with other devices, associated in series and distributed along the duct may absorb the excess of pressure and outflow generated by the transitory and keep the applied loading inferior to the resistance supplied by the installation.

This research presents methods of creating digital maps for floodplain delineation and flood probability studies and storing them in a geodatabase. Methods for creating a geodatabase for water resources outside of a GIS are presented. The geodatabase follows the ArcHydro data model. Methods are also shown for creating digital flood maps and storing them in the geodatabase. These flood maps, defining the floodplain boundary and flood probability, are stored in a digital format ready for use in a FEMA flood hazard project, allowing for better archival methods and reproducibility.

La gestion de l’eau est un aspect central de la pérennité séculaire des oasis sahariennes et de leurs dynamiques économiques. En cette matière, il est important de faire la part entre les systèmes traditionnels et les systèmes « modernes » qui ont très largement bouleversé l’écosystème oasien. L’oasis du Tāfīlālt (Maroc), siège de l’émirat de Sid̲j̲ilmāsa et « port » du commerce caravanier entre le VIIIe et le XVe siècle, constitue un excellent observatoire de l’adaptation humaine en milieu aride. Afin de disposer de toutes les données nécessaires à notre réflexion sur l’hydraulique de Sid̲j̲ilmāsa, nous avons constitué un large corpus documentaire, issu du dépouillement de la littérature scientifique autour de la thématique générale de l’eau, focalisé principalement sur les études archéologiques et les techniques de mobilisation. Après une contextualisation du site archéologique de Sid̲j̲ilmāsa dans son environnement oasien et sa documentation écrite depuis le Moyen Âge, nous dressons un état des vestiges hydrauliques découverts depuis 2012 par la mission franco-marocaine. Observables sur l’ensemble des zones de fouilles, ces structures peuvent être associées au captage, à l’adduction ou au stockage de l’eau, ainsi qu’à l’évacuation des eaux usées. L’analyse et la description technique de celles-ci puis leur insertion dans un contexte stratigraphique général, permet, en mobilisant les données du corpus, de proposer des hypothèses fonctionnelles et une évolution des pratiques hydrauliques dans la Sid̲j̲ilmāsa médiévale. Dans la partie finale de la thèse, nous traitons notamment de la représentation symbolique de l’eau à Sid̲j̲ilmāsa, véhiculée depuis le Moyen Âge, et des changements dans les modes d’approvisionnement des populations locales au cours du temps, en nous basant sur les considérations archéologiques présentées durant tout ce travail de recherche et sur nos observations actuelles, afin de proposer un essai d’hydrohistoire du Tāfīlālt. / Water management is a central aspect of the secular sustainability of Saharan oases and their economic dynamics. In this matter, it is important to distinguish between traditional systems and "modern" systems that have widely changed the oasian ecosystem. The oasis of Tāfīlālt (Morocco), seat of the emirate of Sid̲j̲ilmāsa and "port" of the caravan trade between the eighth and fifteenth century, is an excellent observatory of human adaptation in an arid environment. In order to have all the necessary data for our reflection on the hydraulics of Sid̲j̲ilmāsa, we have constituted a large corpus of documents, resulting from the analysis of the scientific literature around the general theme of water, focused mainly on archaeological studies and mobilization techniques. Following a contextualization of the archaeological site of Sid̲j̲ilmāsa in its oasis environment and its written documentation since the Middle Age, we establish a report of the hydraulic remains discovered since 2012 by the french-moroccan mission. Observable over all the excavation areas, these structures can be associated with the capture, supply or storage of water, as well as the disposal of wastewater. The analysis and the technical description of these remains then their insertion in a general stratigraphic context, allow us, by also mobilizing the data of the corpus, to propose functional hypotheses and an evolution of hydraulic practices in medieval Sid̲j̲ilmāsa. In the final part of the thesis, we deal in particular with the symbolic representation of water in Sid̲j̲ilmāsa conveyed since the Middle Age and changes in the way of supply of local populations over time, based on the archaeological considerations presented during all this research work and on our current observations, in order to provide an essay of hydrohistory in Tāfīlālt.