This research presents improvements to the velocity field reconstruction process achieved through computer vision. The first improvement of the velocity reconstruction process is the automation of the scanning laser Doppler vibrometer (SLDV) pose procedure. This automated process results in superior estimates of the position and orientation of the SLDV. The second improvement is the refinement of the formulation for reconstruction of the velocity field. The refined formulation permits faster computation, evaluation, and interpretation of the reconstructed structural velocity field. Taken together, these new procedures significantly improve the overall velocity reconstruction process which results in better, unbiased out-of-plane velocity estimates in the presence of noise. The automation of the SLDV pose procedure is achieved through a computer vision model of the SLDV. The SLDV is modeled as a projective camera, i.e. an imager which preserves projectivities. This projective camera model permits the precise association of object features with image features. Specifically, circular features in the object space are seen by the SLDV as ellipses in the image space. In order to extract object points, the bitangents among the circular features are constructed and the bitangent points selected. The accuracy and precision of the object points are improved through the use of a calibrated object whose circular features are measured with a coordinate measuring machine. The corresponding image points are determined by constructing the bitangents among the ellipses and selecting the tangent points. Taken together, these object/image bitangent point sets are a significantly improved data set for previously developed SLDV pose algorithms. Experimental verification of this automated pose procedure includes demonstrated repeatability, independent validation of the estimated pose parameters, and comparison of the estimated poses with previous methods. The refinement of the velocity reconstruction formulation is a direct result of the computer vision viewpoint adapted for this research. By viewing the velocity data as images of the harmonically excited structure's velocity field, analytical techniques developed for holographic interferometry are extended and applied to SLDV velocity images. Specifically, the "absolute" and "relative" fringe-order methods are used to reconstruct the velocity field with the "best" set of bases. Full and partial least squares solutions with experimental velocity data are calculated. Statistical confidence bounds of the regressed velocity coefficients are analyzed and interpreted to reveal accurate out-of-plane, but poor in-plane velocity estimates. Additionally, the reconstruction process is extended to recover the velocity field of a family of surfaces in the neighborhood of the "real" surface. This refinement relaxes the need for the exact experimental geometry. Finally, the velocity reconstruction procedure is reformulated so that independent least squares solutions are obtained for the two in-plane directions and the out-of plane direction. This formulation divides the original least squares problem into three smaller problems which can be analyzed and interpreted separately. These refinements to the velocity reconstruction process significantly improve the out-of-plane velocity solution and interpretation of the regressed velocity parameters. / Ph. D.

[pt] Escoamentos intermitentes gás-líquido são encontrados em diversas aplicações de engenharia, como em linhas de produção de petróleo e em sistemas de refrigeração de reatores nucleares. O conhecimento detalhado deste padrão de escoamento é indispensável para a construção de modelos matemáticos representativos deste fenômeno físico complexo. No presente trabalho, foi desenvolvido um estudo experimental com o objetivo de fornecer informações que possibilitem a melhoria dos modelos existentes para o escoamento bifásico intermitente em duto horizontal. A técnica de velocimetria por imagem de partículas estereoscópica (SPIV) de alta frequência foi empregada, em conjunto com a técnica de fluorescência induzida por laser (LIF), permitindo a obtenção de campos de velocidade na região do pistão de líquido, a jusante da bolha alongada, e na região do filme líquido, a montante da bolha. O arranjo experimental possibilitou a medição das três componentes do vetor velocidade do escoamento bifásico água-glicerina e ar na seção transversal de uma tubulação horizontal de 40mm de diâmetro interno. Os resultados obtidos, originais na literatura, mostraram a evolução detalhada das três componentes dos campos médios do vetor velocidade ao longo da passagem da bolha alongada durante o escoamento intermitente. / [en] Gas-liquid intermittent flows can be found in many engineering applications, such as oil production lines and nuclear reactors cooling systems. The detailed knowledge of this flow pattern is necessary for the development of accurate mathematical models of this complex phenomenon. In this work, an experimental study was developed with the goal to provide data that could be used to improve the existing models for two-phase intermittent flow in horizontal pipes. The high-frequency stereoscopic particle image velocimetry (SPIV) technique was employed along with the laser induced fluorescence (LIF) technique, allowing the measurement of velocity fields in the liquid slug, downstream of the elongated bubble, and in the liquid film, upstream of the elongated bubble. The experimental arrangement allowed the measurement of the three components of the velocity vector in an intermittent two-phase water-glycerine and air flow, in a transversal sections of a 40mm internal diameter horizontal pipe. The results obtained revealed original detailed information on the evolution of the three components of the averaged velocity field associated with the passage of the elongated bubble characteristic of the intermittent flow.

Campaign GPS measurements during 2001-2003 in the transition between subduction and collision of the Banda arc reveal how strain is partitioned away from the trench and distributed to other parts of the arc-trench system. Genrich, et. al. (1996) conducted a GPS campaign (1992-1994) throughout the Eastern Sunda and Banda arcs that demonstrated partial accretion of the arc to the Australian plate. We reoccupied many of the sites from this earlier study and 7 additional stations, 3 of which are new benchmarks. Our study shortened many baselines and extended the observation epoch to ten years for many key stations. The resulting GPS velocity field for the active Banda arc-continent collision reveals: 1) several mostly rigid crustal blocks exist in the transition from subduction to collision, 2) relative to an Asian reference frame, most of these blocks move in the same direction as the Australian lower plate, but at different rates, 3) block boundaries may exist between the islands of Lombok and Komodo, Flores and Sumba, Savu and West Timor, and between Timor and Darwin, 4) the Timor Trough may account for at least 20 mm/yr of motion between Timor and Darwin, 5) a major transverse fault off the coast of West Timor separates the Savu/Flores/Sumba block from the Timor/Wetar Block and may account for variations in movement in Rote, 6) the Flores thrust moves the eastern Sunda arc north relative to Asia by decreasing amounts to the west, 7) the back-arc Wetar Thrust system takes up the majority of plate convergence between Australia and Asia, and 8) fault boundaries are not found between many blocks, such as various islands of the Sunda arc and forearc with different amounts of motion.

The velocity field in the wake of a small scale flexible parachute canopy was measured using two-dimensional particle image velocimetry. The experiments were performed in a water tunnel with the Reynolds number ranging from 3.0-6.0 x 104. Both a fully inflated canopy and the inflation phase were investigated in a constant freestream (i.e. an infinite mass condition). The fully inflated canopy experienced a cyclic“breathing" which corresponded to the shedding of a vortex ring from the canopy. The normalized breathing frequency had a value of 0.56 +/- 0.03. The investigation of the canopy inflation showed that during the early stages of the inflation, the boundary layer on the canopy surface remains attached to the canopy while the canopy diameter increases substantially. The boundary layer begins to separate near the apex region when the diameter is ~68% of the fully inflated diameter. The separation point then progresses upstream from the canopy apex region toward the canopy skirt. During this time period, the force rapidly increases to its maximum value while the separation point of the boundary layer moves upstream towards the skirt. The force then declines rapidly and the separated boundary layer rolls-up into a large vortex ring near the canopy skirt. At the same time, the canopy is drawn into an over-expanded state after which the cyclic breathing initiates. The unsteady potential force was estimated from the rate of change of the canopy volume. It contributed no more than 10% of the peak opening force and was only significant during the early stages of inflation. The majority of the opening force was the result of the time rate of change of the fluid impulse. It accounts for approximately 60% of the peak opening force. This result shows that the formation of the viscous wake is the primary factor in the peak drag force of the canopy.

Les procédés de séparation membranaire, utilisés couramment dans de nombreux domaines industriels, comme l’agro-alimentaire, le traitement des eaux ou les biotechnologies, sont de plus en plus mis en œuvre dans le domaine des bioraffineries. L’ultrafiltration tangentielle, par exemple, montre un fort potentiel dans l’étape de séparation des matières premières comme les nanocristaux de cellulose pour les transformer en biomasse. Cependant, l’augmentation de la concentration en particules à la surface de la membrane limite ce procédé, entrainant la formation des phénomènes de polarisation de concentration et de colmatage, réduisant les performances de filtration. Ces travaux de thèse ont pour objectif d’améliorer la compréhension des mécanismes de formation de ces phénomènes. Deux méthodes de caractérisation couvrant les échelles nanométriques à micrométiques ont été mises au point, grâce au développement de cellules de filtration couplant l’ultrafiltration à la diffusion de rayons X aux petits angles d’une part, et à la micro vélocimétrie par images de particules d’autre part. Ces mesures effectuées in-situ lors de la filtration tangentielle de suspensions de nanocristaux de cellulose et d’argile de Laponite, ont permis de caractériser l’organisation structurale et le champ hydrodynamique au sein des couches de polarisation. La corrélation de ces résultats avec les lois de comportement rhéologique des suspensions ont permis d’accéder pour la première fois aux champs de contraintes dans les couches de polarisation de concentration et de colmatage lors du procédé. / Membrane separation processes commonly used in several industrial applications, like bio and agro industries, waste water and clean water treatments, are more and more exploited in biorefinery. As an example, cross-flow ultrafiltration process shows a high potential in separation protocol of raw feed components like cellulose nanocrystals to produce biomass. This process is limited by the increase of particles concentration at the membrane surface, which conducts to phenomena named concentration polarization and fouling, which decrease the filtration performance. The PhD work objective is to bring a better understanding of the mechanisms involved in the formation of these phenomena. Two characterization methods covering length scales from nanometer to micrometer have been developed thanks to new designed tangential ultrafiltration cells allowing to link the ultrafiltration process to small angle X rays scattering and to micro particle image velocimetry. These measurement performed in-situ during ultrafiltration of nanocrystal celluloses and Laponite clay suspensions have allowed characterizing the structural organization and the velocity field within the concentration polarization layers. The correlation of these results with the rheological behavior properties of the suspensions, have permitted to access for the first time to the stress field within the concentration polarization and fouling layer during the tangential ultrafiltration process.

Os mecanismos de transposição de peixes (MTP) são estruturas ou sistemas que possibilitam a migração da ictiofauna entre as partes de jusante/montante/jusante de uma barragem. As escadas para peixes representam um dos tipos de MTP mais conhecidos no mundo e apresentam diversas configurações geométricas. A escolha do tipo de escada deve atender às características natatórias dos peixes selecionados para transporem o obstáculo. Para algumas espécies, como o salmão, já se conhecem geometrias adequadas, entretanto, para a maioria das espécies isto não ocorre e muitos projetos têm demonstrado desempenho insatisfatório. No Brasil, encontra-se uma imensa diversidade de espécies de peixes, cujas características natatórias diferem em muito das apresentadas pelos salmonídeos. Este fato, associado à crescente exigência da implantação de MTP nos barramentos, através de leis estaduais ambientais, torna necessária a definição de estruturas adequadas à ictiofauna brasileira. A validação dos critérios de projeto passa, obrigatoriamente, por estudos que avaliem as características hidráulicas das estruturas propostas e a interação do fluxo com os padrões natatórios da ictiofauna. O número de pesquisas relacionadas ao funcionamento hidráulico de escadas para peixes vem crescendo, entretanto ainda são insuficientes, não existindo um consenso sobre os critérios, seja para sua caracterização completa, seja para definir sobre quais parâmetros devem ser considerados. Os padrões de turbulência do escoamento em escadas para peixes, cujas características supõem-se relacionarem-se com o grau de aceitação ou rejeição das espécies, são praticamente desconhecidos. Neste trabalho realizou-se a caracterização hidráulica através do estudo experimental, de três tipos de escadas para peixes: (1) com ranhura vertical; (2) com descarregador de superfície e (3) com orifício de fundo. As estruturas foram construídas nos laboratórios do Instituto de Pesquisas Hidráulicas da Universidade Federal do Rio Grande do Sul – IPH/UFRGS e no Laboratório Nacional de Engenharia Civil – LNEC – Portugal. As seguintes medições foram realizadas: velocidades em três direções, em diferentes planos dos tanques, com velocímetros acústicos Doppler (ADV) e níveis de água da superfície livre com pontas linimétricas e réguas graduadas. Para a estrutura com ranhura vertical ainda foram medidas as pressões médias e suas flutuações, junto ao fundo do canal, com transdutores piezoresistivos. Para cada uma das estruturas realizaram-se ensaios com três descargas. Além de definidas as características médias do escoamento, os dados de velocidades, que passaram por um processo de aplicação de filtros sem substituição, possibilitaram a avaliação de parâmetros de turbulência, entre eles a energia cinética da turbulência, a intensidade da turbulência e as tensões de Reynolds. No modelo da escada para peixes com ranhuras verticais verificou-se que os parâmetros hidráulicos estão de acordo com estruturas similares da bibliografia, entre eles, coeficiente de descarga, vazão adimensional e coeficiente de cisalhamento. Os campos de pressão junto ao fundo refletem o comportamento da superfície livre do escoamento. Através do mapeamento das velocidades dentro do tanque da escada do tipo ranhura vertical, foi possível caracterizar as duas zonas de recirculação e a região do jato principal. Os máximos valores médios de velocidade encontram-se na seção da ranhura, não excedendo 1,00 m/s (no modelo). Além disso, foi possível reconhecer as regiões de maior energia cinética da turbulência que apresentaram valores de até 1000 cm2/s2 na região do jato principal, as quais coincidem com as zonas de maiores tensões de Reynolds da ordem de até 30 N/m2. A partir das velocidades médias e em função das velocidades de nado dos peixes obtidos na literatura, foi possível a identificação de locais que atuam como “barreiras” ao deslocamento de determinada espécie. A avaliação qualitativa do comportamento da trajetória dos peixes dentro dos tanques mostrou-se de acordo com a definição destas “barreiras” hidráulicas e com a avaliação do comportamento dos campos de energia cinética da turbulência e das tensões de Reynolds. No modelo da escada do tipo descarregador de superfície observaram-se as máximas velocidades médias sobre o descarregador, com valores de até 1,73 m/s. Verifica-se que na maior parte do tanque as velocidades médias não ultrapassam 40% da velocidade potencial. Foram encontrados valores de energia cinética da turbulência até 2000 cm2/s2, com valores na maior parte do tanque em torno de 200 cm2/s2. Quanto aos campos de tensões de Reynolds, têm-se, na maior parte do tanque, os valores entre −5 e 5 N/m2, sendo que na região do jato mergulhante, os valores chegam até 30 N/m2. Na escada com orifícios de fundo verificaram-se as maiores velocidades médias nos planos sob influência do fluxo principal proveniente do orifício. Não foi possível a medição da velocidade na seção da abertura, sendo que os valores medidos no tanque não ultrapassaram 50% da velocidade potencial. Os máximos valores de energia cinética da turbulência atingem até 2000 cm2/s2 junto ao fundo, enquanto na região central do tanque, o valor médio é um pouco inferior a 200 cm2/s2. Os valores de tensão de Reynolds encontram-se entre −30 e 30 N/m2, com a maioria das regiões entre −5 e 5 N/m2. Os valores máximos e médios de energia cinética da turbulência e tensões de Reynolds para os modelos com descarregador de superfície e com orifício de fundo encontram-se na mesma faixa. Isto indica que, sob o ponto de vista técnico, possivelmente o critério de escolha entre essas duas estruturas recai nas características da ictiofauna. A passagem com ranhura vertical permite a escolha da profundidade preferencial de nado. No entanto, nessa estrutura, verificase que as componentes médias e turbulentas, nas regiões de descanso, comparando-as com os valores máximos do jato principal, são superiores proporcionalmente, às observadas nas zonas de recirculação das outras duas estruturas. As informações biológicas disponíveis na literatura não permitem a definição de condições preferenciais em relação aos parâmetros de turbulência entre as estruturas aqui avaliadas. No entanto, as informações obtidas nesse trabalho indicam que a energia cinética da turbulência e as tensões de Reynolds podem ser indicativos da tolerância ou preferência dos peixes até certos níveis de turbulência. / Fish facilities are structures or systems that enable fish passage through dams or obstructions. Fishways represent one of the most common fish facilities types worldwide, presenting different geometries and designs. The choice and design of these structures must attend the fish swimming performance and biological characteristics. For some species, as salmon, there are defined designs that can be successfully applied, however, that does not occur for the majority of the species and many projects have showed unsatisfactory efficiency. In Brazil, there is an immense diversity of fish species, whose swimming characteristics are strongly different than the other known species like the salmons. This fact, associated with the increasing requirement of fish facilities implantation in dams, mainly through environmental State Laws, requires the definition of structures adapted to the Brazilian fish. The design criteria validation needs, necessarily, studies to evaluate hydraulic characteristics on structure proposals and the interaction of the flow with swimming abilities. The number of researches related to the hydraulic functioning of fishways is increasing, however they are still insufficient and there is not a consensus on the criteria, either for its complete characterization, either to define which parameters should be considered. The flow turbulence patterns in fishways, whose characteristics are assumed to be related with the degree of acceptance or rejection of the species, are practically unknown. In this study a hydraulic characterization was carried out through an experimental study, including three kinds of fishways: (1) with vertical slots; (2) with rectangular notches and (3) with bottom orifices. The facilities were set up in the Hydraulic Research Institute of the Federal University of Rio Grande do Sul (IPH/UFRGS) and in the National Laboratory of Civil Engineering – LNEC - Portugal. The following measurements were carried out: three-direction velocities, in a 3D-mesh in one pool of each structure, with Acoustic Doppler Velocimeters and water level of the free surface with a point gauge and scales. In the vertical slot fishway it was carried out complementary measurements of pressure in the bottom of the channel, with transducers. For each structure three discharges were tested. Besides defining the mean flow characteristics, the velocity time data, filtered (through a digital process) without substitution, allowed to analyze some turbulence parameters, as turbulence kinetic energy, turbulence intensity and Reynolds’ shear stresses. In the vertical slot fishway model it was verified that the hydraulic parameters are in agreement with similar structures of the literature, among them, discharge coefficient, adimensional discharge and friction factor. The bottom pressure field agrees with the behavior of the free-surface flow. Two recirculation zones and the area of the main jet were characterized through the velocities distribution inside the vertical slot fishway pool. The maximum mean velocity values were found in the slot section, not exceeding 1.00 m/s (in the model). Moreover, it was possible to recognize the areas with larger turbulence kinetic energy that presented values of up to 1000 cm²/s² in the main jet area, which correspond to the largest Reynolds’ shear stresses values of up to 30 N/m². Considering mean velocities data and fish swimming capabilities, it was possible to identify regions that are insurmountable by the fish. The qualitative approach of the fish trajectory inside the structure agrees with the insurmountable regions described through mean velocities and with the distribution of turbulence kinetic energy and Reynolds’ stresses. In the fishway model with rectangular notches, the maximum mean velocities were observed on the weir, with values of up to 1.73 m/s. In the major part of the pool, mean velocities do not surpass 40% of the potential velocity. Values up to 2000 cm²/s² for turbulence kinetic energy were found, with values in the major part of the pool close to 200 cm²/s². For Reynolds’ stresses, the major part of the structure works with values in the range of −5 and 5 N/m², and in the jet entrance pool region the values are of up to 30 N/m². In the fishway with bottom orifices the largest mean velocities were verified in the plans under influence of the main flow connecting consecutive orifices. The measurement of the velocities in the orifice section was not possible and the values measured in the pool did not exceed 50% of the potential velocity. The maximum values of turbulence kinetic energy reached up to 2000 cm²/s² close to the bottom channel, while in the central area of the pool, the mean value is lower than 200 cm2/s2. The values of Reynolds’ shear stresses are between −30 and 30 N/m2, with the major part between−5 and 5 N/m2. The maximum and mean values of turbulence kinetic energy and Reynolds’ stresses in the models with rectangular notches and with orifice are in the same range. It indicates that the choice between these two structures relapses in the fish swimming characteristics. The passage with vertical slot allows the choice of the swimming depth preference. However, in the resting areas of this structure, it is verified that the mean and turbulent components when compared with the maximum values of the main jet, are higher proportionally, to the ones observed in the recirculation zones of the other two structures. The biological information available in the literature does not allow the definition of preferential conditions in relation to the turbulence parameters among the structures here appraised. However, the information obtained in this work indicates that the turbulence kinetic energy and Reynolds’ shear stress can be indicatives of the tolerance or preference of the fish to certain turbulence levels.

Os mecanismos de transposição de peixes (MTP) são estruturas ou sistemas que possibilitam a migração da ictiofauna entre as partes de jusante/montante/jusante de uma barragem. As escadas para peixes representam um dos tipos de MTP mais conhecidos no mundo e apresentam diversas configurações geométricas. A escolha do tipo de escada deve atender às características natatórias dos peixes selecionados para transporem o obstáculo. Para algumas espécies, como o salmão, já se conhecem geometrias adequadas, entretanto, para a maioria das espécies isto não ocorre e muitos projetos têm demonstrado desempenho insatisfatório. No Brasil, encontra-se uma imensa diversidade de espécies de peixes, cujas características natatórias diferem em muito das apresentadas pelos salmonídeos. Este fato, associado à crescente exigência da implantação de MTP nos barramentos, através de leis estaduais ambientais, torna necessária a definição de estruturas adequadas à ictiofauna brasileira. A validação dos critérios de projeto passa, obrigatoriamente, por estudos que avaliem as características hidráulicas das estruturas propostas e a interação do fluxo com os padrões natatórios da ictiofauna. O número de pesquisas relacionadas ao funcionamento hidráulico de escadas para peixes vem crescendo, entretanto ainda são insuficientes, não existindo um consenso sobre os critérios, seja para sua caracterização completa, seja para definir sobre quais parâmetros devem ser considerados. Os padrões de turbulência do escoamento em escadas para peixes, cujas características supõem-se relacionarem-se com o grau de aceitação ou rejeição das espécies, são praticamente desconhecidos. Neste trabalho realizou-se a caracterização hidráulica através do estudo experimental, de três tipos de escadas para peixes: (1) com ranhura vertical; (2) com descarregador de superfície e (3) com orifício de fundo. As estruturas foram construídas nos laboratórios do Instituto de Pesquisas Hidráulicas da Universidade Federal do Rio Grande do Sul – IPH/UFRGS e no Laboratório Nacional de Engenharia Civil – LNEC – Portugal. As seguintes medições foram realizadas: velocidades em três direções, em diferentes planos dos tanques, com velocímetros acústicos Doppler (ADV) e níveis de água da superfície livre com pontas linimétricas e réguas graduadas. Para a estrutura com ranhura vertical ainda foram medidas as pressões médias e suas flutuações, junto ao fundo do canal, com transdutores piezoresistivos. Para cada uma das estruturas realizaram-se ensaios com três descargas. Além de definidas as características médias do escoamento, os dados de velocidades, que passaram por um processo de aplicação de filtros sem substituição, possibilitaram a avaliação de parâmetros de turbulência, entre eles a energia cinética da turbulência, a intensidade da turbulência e as tensões de Reynolds. No modelo da escada para peixes com ranhuras verticais verificou-se que os parâmetros hidráulicos estão de acordo com estruturas similares da bibliografia, entre eles, coeficiente de descarga, vazão adimensional e coeficiente de cisalhamento. Os campos de pressão junto ao fundo refletem o comportamento da superfície livre do escoamento. Através do mapeamento das velocidades dentro do tanque da escada do tipo ranhura vertical, foi possível caracterizar as duas zonas de recirculação e a região do jato principal. Os máximos valores médios de velocidade encontram-se na seção da ranhura, não excedendo 1,00 m/s (no modelo). Além disso, foi possível reconhecer as regiões de maior energia cinética da turbulência que apresentaram valores de até 1000 cm2/s2 na região do jato principal, as quais coincidem com as zonas de maiores tensões de Reynolds da ordem de até 30 N/m2. A partir das velocidades médias e em função das velocidades de nado dos peixes obtidos na literatura, foi possível a identificação de locais que atuam como “barreiras” ao deslocamento de determinada espécie. A avaliação qualitativa do comportamento da trajetória dos peixes dentro dos tanques mostrou-se de acordo com a definição destas “barreiras” hidráulicas e com a avaliação do comportamento dos campos de energia cinética da turbulência e das tensões de Reynolds. No modelo da escada do tipo descarregador de superfície observaram-se as máximas velocidades médias sobre o descarregador, com valores de até 1,73 m/s. Verifica-se que na maior parte do tanque as velocidades médias não ultrapassam 40% da velocidade potencial. Foram encontrados valores de energia cinética da turbulência até 2000 cm2/s2, com valores na maior parte do tanque em torno de 200 cm2/s2. Quanto aos campos de tensões de Reynolds, têm-se, na maior parte do tanque, os valores entre −5 e 5 N/m2, sendo que na região do jato mergulhante, os valores chegam até 30 N/m2. Na escada com orifícios de fundo verificaram-se as maiores velocidades médias nos planos sob influência do fluxo principal proveniente do orifício. Não foi possível a medição da velocidade na seção da abertura, sendo que os valores medidos no tanque não ultrapassaram 50% da velocidade potencial. Os máximos valores de energia cinética da turbulência atingem até 2000 cm2/s2 junto ao fundo, enquanto na região central do tanque, o valor médio é um pouco inferior a 200 cm2/s2. Os valores de tensão de Reynolds encontram-se entre −30 e 30 N/m2, com a maioria das regiões entre −5 e 5 N/m2. Os valores máximos e médios de energia cinética da turbulência e tensões de Reynolds para os modelos com descarregador de superfície e com orifício de fundo encontram-se na mesma faixa. Isto indica que, sob o ponto de vista técnico, possivelmente o critério de escolha entre essas duas estruturas recai nas características da ictiofauna. A passagem com ranhura vertical permite a escolha da profundidade preferencial de nado. No entanto, nessa estrutura, verificase que as componentes médias e turbulentas, nas regiões de descanso, comparando-as com os valores máximos do jato principal, são superiores proporcionalmente, às observadas nas zonas de recirculação das outras duas estruturas. As informações biológicas disponíveis na literatura não permitem a definição de condições preferenciais em relação aos parâmetros de turbulência entre as estruturas aqui avaliadas. No entanto, as informações obtidas nesse trabalho indicam que a energia cinética da turbulência e as tensões de Reynolds podem ser indicativos da tolerância ou preferência dos peixes até certos níveis de turbulência. / Fish facilities are structures or systems that enable fish passage through dams or obstructions. Fishways represent one of the most common fish facilities types worldwide, presenting different geometries and designs. The choice and design of these structures must attend the fish swimming performance and biological characteristics. For some species, as salmon, there are defined designs that can be successfully applied, however, that does not occur for the majority of the species and many projects have showed unsatisfactory efficiency. In Brazil, there is an immense diversity of fish species, whose swimming characteristics are strongly different than the other known species like the salmons. This fact, associated with the increasing requirement of fish facilities implantation in dams, mainly through environmental State Laws, requires the definition of structures adapted to the Brazilian fish. The design criteria validation needs, necessarily, studies to evaluate hydraulic characteristics on structure proposals and the interaction of the flow with swimming abilities. The number of researches related to the hydraulic functioning of fishways is increasing, however they are still insufficient and there is not a consensus on the criteria, either for its complete characterization, either to define which parameters should be considered. The flow turbulence patterns in fishways, whose characteristics are assumed to be related with the degree of acceptance or rejection of the species, are practically unknown. In this study a hydraulic characterization was carried out through an experimental study, including three kinds of fishways: (1) with vertical slots; (2) with rectangular notches and (3) with bottom orifices. The facilities were set up in the Hydraulic Research Institute of the Federal University of Rio Grande do Sul (IPH/UFRGS) and in the National Laboratory of Civil Engineering – LNEC - Portugal. The following measurements were carried out: three-direction velocities, in a 3D-mesh in one pool of each structure, with Acoustic Doppler Velocimeters and water level of the free surface with a point gauge and scales. In the vertical slot fishway it was carried out complementary measurements of pressure in the bottom of the channel, with transducers. For each structure three discharges were tested. Besides defining the mean flow characteristics, the velocity time data, filtered (through a digital process) without substitution, allowed to analyze some turbulence parameters, as turbulence kinetic energy, turbulence intensity and Reynolds’ shear stresses. In the vertical slot fishway model it was verified that the hydraulic parameters are in agreement with similar structures of the literature, among them, discharge coefficient, adimensional discharge and friction factor. The bottom pressure field agrees with the behavior of the free-surface flow. Two recirculation zones and the area of the main jet were characterized through the velocities distribution inside the vertical slot fishway pool. The maximum mean velocity values were found in the slot section, not exceeding 1.00 m/s (in the model). Moreover, it was possible to recognize the areas with larger turbulence kinetic energy that presented values of up to 1000 cm²/s² in the main jet area, which correspond to the largest Reynolds’ shear stresses values of up to 30 N/m². Considering mean velocities data and fish swimming capabilities, it was possible to identify regions that are insurmountable by the fish. The qualitative approach of the fish trajectory inside the structure agrees with the insurmountable regions described through mean velocities and with the distribution of turbulence kinetic energy and Reynolds’ stresses. In the fishway model with rectangular notches, the maximum mean velocities were observed on the weir, with values of up to 1.73 m/s. In the major part of the pool, mean velocities do not surpass 40% of the potential velocity. Values up to 2000 cm²/s² for turbulence kinetic energy were found, with values in the major part of the pool close to 200 cm²/s². For Reynolds’ stresses, the major part of the structure works with values in the range of −5 and 5 N/m², and in the jet entrance pool region the values are of up to 30 N/m². In the fishway with bottom orifices the largest mean velocities were verified in the plans under influence of the main flow connecting consecutive orifices. The measurement of the velocities in the orifice section was not possible and the values measured in the pool did not exceed 50% of the potential velocity. The maximum values of turbulence kinetic energy reached up to 2000 cm²/s² close to the bottom channel, while in the central area of the pool, the mean value is lower than 200 cm2/s2. The values of Reynolds’ shear stresses are between −30 and 30 N/m2, with the major part between−5 and 5 N/m2. The maximum and mean values of turbulence kinetic energy and Reynolds’ stresses in the models with rectangular notches and with orifice are in the same range. It indicates that the choice between these two structures relapses in the fish swimming characteristics. The passage with vertical slot allows the choice of the swimming depth preference. However, in the resting areas of this structure, it is verified that the mean and turbulent components when compared with the maximum values of the main jet, are higher proportionally, to the ones observed in the recirculation zones of the other two structures. The biological information available in the literature does not allow the definition of preferential conditions in relation to the turbulence parameters among the structures here appraised. However, the information obtained in this work indicates that the turbulence kinetic energy and Reynolds’ shear stress can be indicatives of the tolerance or preference of the fish to certain turbulence levels.

De nombreuses applications industrielles mettent en jeu des fluides complexes qui possèdent souvent un seuil d'écoulement leur permettant de résister à des efforts finis sans s'écouler. Par ailleurs, ces fluides peuvent glisser aux parois lorsque les conditions interfaciales sont favorables. Toutes ces propriétés influencent leurs écoulements autour d'obstacles. Cette thèse se propose de comprendre ces écoulements dans le domaine où les vitesses d'écoulement sont telles que les effets inertiels peuvent être négligés devant les effets visqueux eux-mêmes faibles par rapport aux effets plastiques. Elle analyse l'influence de la vitesse et du glissement sur la force de traînée et les champs cinématiques générés par l'écoulement très lent et en régime permanent d'un fluide à seuil autour d'obstacles aux surfaces adhérentes ou glissantes. Les géométries considérées sont le disque, la sphère, le cône et la plaque plane. Le fluide utilisé a un comportement élasto-viscoplastique pouvant être décrit par les modèles de Herschel-Bulkley et de Hooke. Ce comportement a été caractérisé en volume et en présence de glissement par des mesures rhéométriques. Le nombre adimensionnel clé de l'étude est le nombre d'Oldroyd, ratio entre les effets plastiques et les effets visqueux, compris ici entre 10 et 200. Les mesures de forces de traînée ont montré qu'indépendamment de l'obstacle et des conditions interfaciales, le coefficient de traînée diminue avec le nombre d'Oldroyd et tend vers une valeur asymptotique. Cette valeur montre qu'au-delà d'un certain nombre d'Oldroyd, ce coefficient n'est plus gouverné par la vitesse mais dépend uniquement du seuil et de la surface caractéristique de l'obstacle. Elle permet de calculer un critère de stabilité pour lequel l'objet est maintenu en suspension. Les champs cinématiques déterminés par PIV ont permis de caractériser la forme et l'étendue des zones rigides et cisaillées. Les mesures de forces de traînée et de champs cinématiques ont permis de quantifier la contribution des contraintes normales et tangentielles dans la force de traînée totale. La présence de glissement aux parois de l'obstacle diminue significativement le coefficient de traînée et modifie la morphologie de l'écoulement en réduisant l'étendue des zones cisaillées. Une simulation numérique a été menée dans le cas de la plaque plane avec un modèle élasto-viscoplastique et un code à éléments finis avec points d'intégration Lagrangiens. / Many industrial processes include numerous complex fluids often presenting a yield stress. Those fluids can also slip when interfacial conditions are favorable. All these properties affect their flows around obstacles. This thesis aims to understand such flows in a domain where the flow velocities are so low that inertia effects can be neglected compared to viscous effects which are substantially low compared to plastic effects. It analyzes the influence of the velocity and the slip on the drag force and the kinematic fields of the creeping flow of a yield stress fluid around obstacles either with adhesive or slippery wall. The flow is analyzed in steady regime. The considered geometries are the disc, the sphere, the cone and the flat plate. The fluid used has an elasto-viscoplastic behavior which is modelled by the Herschel-Bulkley and Hooke models. This behavior has been characterized by rheometrical tests performed with adherence and slip conditions. The main non-dimensional number is the Oldroyd number, i.e. the ratio between plastic and viscous effects, which ranges from 10 to 200. The drag forces measurements have shown that regardless of the obstacle and the interfacial conditions, the drag coefficient decreases with the Oldroyd number before tending towards to an asymptotical value. This asymptotical value highlights that for high Oldroyd numbers the drag coefficient is no longer governed by the velocity but depends only on the yield stress and the characteristic section of the obstacle. A stability criterion for which the obstacle is held in suspension has been calculated from it. The kinematic fields determined by PIV have enabled to characterize the shape and the extent of the sheared and static regions. The drag forces and the kinematic fields measurements have enabled to quantify the contribution of the normal and tangential stresses in the total drag force. The wall slip significantly reduces the drag coefficient and also reduces the extent of the sheared zones. A numerical simulation has been performed with an elasto-viscoplastic model by means of a code using finite elements method with Lagrangian integration points in the case of an adhesive flat plane.

Os mecanismos de transposição de peixes (MTP) são estruturas ou sistemas que possibilitam a migração da ictiofauna entre as partes de jusante/montante/jusante de uma barragem. As escadas para peixes representam um dos tipos de MTP mais conhecidos no mundo e apresentam diversas configurações geométricas. A escolha do tipo de escada deve atender às características natatórias dos peixes selecionados para transporem o obstáculo. Para algumas espécies, como o salmão, já se conhecem geometrias adequadas, entretanto, para a maioria das espécies isto não ocorre e muitos projetos têm demonstrado desempenho insatisfatório. No Brasil, encontra-se uma imensa diversidade de espécies de peixes, cujas características natatórias diferem em muito das apresentadas pelos salmonídeos. Este fato, associado à crescente exigência da implantação de MTP nos barramentos, através de leis estaduais ambientais, torna necessária a definição de estruturas adequadas à ictiofauna brasileira. A validação dos critérios de projeto passa, obrigatoriamente, por estudos que avaliem as características hidráulicas das estruturas propostas e a interação do fluxo com os padrões natatórios da ictiofauna. O número de pesquisas relacionadas ao funcionamento hidráulico de escadas para peixes vem crescendo, entretanto ainda são insuficientes, não existindo um consenso sobre os critérios, seja para sua caracterização completa, seja para definir sobre quais parâmetros devem ser considerados. Os padrões de turbulência do escoamento em escadas para peixes, cujas características supõem-se relacionarem-se com o grau de aceitação ou rejeição das espécies, são praticamente desconhecidos. Neste trabalho realizou-se a caracterização hidráulica através do estudo experimental, de três tipos de escadas para peixes: (1) com ranhura vertical; (2) com descarregador de superfície e (3) com orifício de fundo. As estruturas foram construídas nos laboratórios do Instituto de Pesquisas Hidráulicas da Universidade Federal do Rio Grande do Sul – IPH/UFRGS e no Laboratório Nacional de Engenharia Civil – LNEC – Portugal. As seguintes medições foram realizadas: velocidades em três direções, em diferentes planos dos tanques, com velocímetros acústicos Doppler (ADV) e níveis de água da superfície livre com pontas linimétricas e réguas graduadas. Para a estrutura com ranhura vertical ainda foram medidas as pressões médias e suas flutuações, junto ao fundo do canal, com transdutores piezoresistivos. Para cada uma das estruturas realizaram-se ensaios com três descargas. Além de definidas as características médias do escoamento, os dados de velocidades, que passaram por um processo de aplicação de filtros sem substituição, possibilitaram a avaliação de parâmetros de turbulência, entre eles a energia cinética da turbulência, a intensidade da turbulência e as tensões de Reynolds. No modelo da escada para peixes com ranhuras verticais verificou-se que os parâmetros hidráulicos estão de acordo com estruturas similares da bibliografia, entre eles, coeficiente de descarga, vazão adimensional e coeficiente de cisalhamento. Os campos de pressão junto ao fundo refletem o comportamento da superfície livre do escoamento. Através do mapeamento das velocidades dentro do tanque da escada do tipo ranhura vertical, foi possível caracterizar as duas zonas de recirculação e a região do jato principal. Os máximos valores médios de velocidade encontram-se na seção da ranhura, não excedendo 1,00 m/s (no modelo). Além disso, foi possível reconhecer as regiões de maior energia cinética da turbulência que apresentaram valores de até 1000 cm2/s2 na região do jato principal, as quais coincidem com as zonas de maiores tensões de Reynolds da ordem de até 30 N/m2. A partir das velocidades médias e em função das velocidades de nado dos peixes obtidos na literatura, foi possível a identificação de locais que atuam como “barreiras” ao deslocamento de determinada espécie. A avaliação qualitativa do comportamento da trajetória dos peixes dentro dos tanques mostrou-se de acordo com a definição destas “barreiras” hidráulicas e com a avaliação do comportamento dos campos de energia cinética da turbulência e das tensões de Reynolds. No modelo da escada do tipo descarregador de superfície observaram-se as máximas velocidades médias sobre o descarregador, com valores de até 1,73 m/s. Verifica-se que na maior parte do tanque as velocidades médias não ultrapassam 40% da velocidade potencial. Foram encontrados valores de energia cinética da turbulência até 2000 cm2/s2, com valores na maior parte do tanque em torno de 200 cm2/s2. Quanto aos campos de tensões de Reynolds, têm-se, na maior parte do tanque, os valores entre −5 e 5 N/m2, sendo que na região do jato mergulhante, os valores chegam até 30 N/m2. Na escada com orifícios de fundo verificaram-se as maiores velocidades médias nos planos sob influência do fluxo principal proveniente do orifício. Não foi possível a medição da velocidade na seção da abertura, sendo que os valores medidos no tanque não ultrapassaram 50% da velocidade potencial. Os máximos valores de energia cinética da turbulência atingem até 2000 cm2/s2 junto ao fundo, enquanto na região central do tanque, o valor médio é um pouco inferior a 200 cm2/s2. Os valores de tensão de Reynolds encontram-se entre −30 e 30 N/m2, com a maioria das regiões entre −5 e 5 N/m2. Os valores máximos e médios de energia cinética da turbulência e tensões de Reynolds para os modelos com descarregador de superfície e com orifício de fundo encontram-se na mesma faixa. Isto indica que, sob o ponto de vista técnico, possivelmente o critério de escolha entre essas duas estruturas recai nas características da ictiofauna. A passagem com ranhura vertical permite a escolha da profundidade preferencial de nado. No entanto, nessa estrutura, verificase que as componentes médias e turbulentas, nas regiões de descanso, comparando-as com os valores máximos do jato principal, são superiores proporcionalmente, às observadas nas zonas de recirculação das outras duas estruturas. As informações biológicas disponíveis na literatura não permitem a definição de condições preferenciais em relação aos parâmetros de turbulência entre as estruturas aqui avaliadas. No entanto, as informações obtidas nesse trabalho indicam que a energia cinética da turbulência e as tensões de Reynolds podem ser indicativos da tolerância ou preferência dos peixes até certos níveis de turbulência. / Fish facilities are structures or systems that enable fish passage through dams or obstructions. Fishways represent one of the most common fish facilities types worldwide, presenting different geometries and designs. The choice and design of these structures must attend the fish swimming performance and biological characteristics. For some species, as salmon, there are defined designs that can be successfully applied, however, that does not occur for the majority of the species and many projects have showed unsatisfactory efficiency. In Brazil, there is an immense diversity of fish species, whose swimming characteristics are strongly different than the other known species like the salmons. This fact, associated with the increasing requirement of fish facilities implantation in dams, mainly through environmental State Laws, requires the definition of structures adapted to the Brazilian fish. The design criteria validation needs, necessarily, studies to evaluate hydraulic characteristics on structure proposals and the interaction of the flow with swimming abilities. The number of researches related to the hydraulic functioning of fishways is increasing, however they are still insufficient and there is not a consensus on the criteria, either for its complete characterization, either to define which parameters should be considered. The flow turbulence patterns in fishways, whose characteristics are assumed to be related with the degree of acceptance or rejection of the species, are practically unknown. In this study a hydraulic characterization was carried out through an experimental study, including three kinds of fishways: (1) with vertical slots; (2) with rectangular notches and (3) with bottom orifices. The facilities were set up in the Hydraulic Research Institute of the Federal University of Rio Grande do Sul (IPH/UFRGS) and in the National Laboratory of Civil Engineering – LNEC - Portugal. The following measurements were carried out: three-direction velocities, in a 3D-mesh in one pool of each structure, with Acoustic Doppler Velocimeters and water level of the free surface with a point gauge and scales. In the vertical slot fishway it was carried out complementary measurements of pressure in the bottom of the channel, with transducers. For each structure three discharges were tested. Besides defining the mean flow characteristics, the velocity time data, filtered (through a digital process) without substitution, allowed to analyze some turbulence parameters, as turbulence kinetic energy, turbulence intensity and Reynolds’ shear stresses. In the vertical slot fishway model it was verified that the hydraulic parameters are in agreement with similar structures of the literature, among them, discharge coefficient, adimensional discharge and friction factor. The bottom pressure field agrees with the behavior of the free-surface flow. Two recirculation zones and the area of the main jet were characterized through the velocities distribution inside the vertical slot fishway pool. The maximum mean velocity values were found in the slot section, not exceeding 1.00 m/s (in the model). Moreover, it was possible to recognize the areas with larger turbulence kinetic energy that presented values of up to 1000 cm²/s² in the main jet area, which correspond to the largest Reynolds’ shear stresses values of up to 30 N/m². Considering mean velocities data and fish swimming capabilities, it was possible to identify regions that are insurmountable by the fish. The qualitative approach of the fish trajectory inside the structure agrees with the insurmountable regions described through mean velocities and with the distribution of turbulence kinetic energy and Reynolds’ stresses. In the fishway model with rectangular notches, the maximum mean velocities were observed on the weir, with values of up to 1.73 m/s. In the major part of the pool, mean velocities do not surpass 40% of the potential velocity. Values up to 2000 cm²/s² for turbulence kinetic energy were found, with values in the major part of the pool close to 200 cm²/s². For Reynolds’ stresses, the major part of the structure works with values in the range of −5 and 5 N/m², and in the jet entrance pool region the values are of up to 30 N/m². In the fishway with bottom orifices the largest mean velocities were verified in the plans under influence of the main flow connecting consecutive orifices. The measurement of the velocities in the orifice section was not possible and the values measured in the pool did not exceed 50% of the potential velocity. The maximum values of turbulence kinetic energy reached up to 2000 cm²/s² close to the bottom channel, while in the central area of the pool, the mean value is lower than 200 cm2/s2. The values of Reynolds’ shear stresses are between −30 and 30 N/m2, with the major part between−5 and 5 N/m2. The maximum and mean values of turbulence kinetic energy and Reynolds’ stresses in the models with rectangular notches and with orifice are in the same range. It indicates that the choice between these two structures relapses in the fish swimming characteristics. The passage with vertical slot allows the choice of the swimming depth preference. However, in the resting areas of this structure, it is verified that the mean and turbulent components when compared with the maximum values of the main jet, are higher proportionally, to the ones observed in the recirculation zones of the other two structures. The biological information available in the literature does not allow the definition of preferential conditions in relation to the turbulence parameters among the structures here appraised. However, the information obtained in this work indicates that the turbulence kinetic energy and Reynolds’ shear stress can be indicatives of the tolerance or preference of the fish to certain turbulence levels.

國家坐標系統是各項測量作業的基礎，而大地基準的選擇及建立更是會直接影響最後的測量成果，進一步的影響各項國家建設、民生工業以及人民的土地財產等權益。板塊運動之中尤其是非線性的板塊運動更是會改變坐標框架中參考站的相對位置，隨著時間的推移進而導致框架的幾何精度下降。而臺灣地處歐亞板塊及菲律賓海板塊的交界處，頻繁的板塊運動會造成地震、火山以及其他的自然災害，且臺灣各個區域也會因為板塊間的非線性運動而往不同的方向旋轉、位移。目前臺灣使用的坐標系統為TWD97 (Taiwan Datum 97 )，是建立於一個固定的線性框架ITRF94(The International Terrestrial Reference Frame 94)下之靜態基準，因此並不能精確的表達臺灣地區複雜的地殼變動情形，臺灣需要進行大地基準的革新以解決坐標框架變形之問題，即是在原有的靜態基準加上速度場與變形模型來改正因地殼運動造成之坐標偏移。本研究利用 2005 年至 2015 年間之臺灣地區連續運行參考站 GPS 觀測資料計算臺灣地區水平速度場情形，並參考日本、紐西蘭等國之速度模型建立方式，以內插、曲面擬合、局部加權回歸散點平滑等方法建立臺灣地區水平速度與變形模型。而臺灣地區參考站坐標解算之水平精度為 2mm-3mm、高程精度為 6mm-10mm，而速度場之年度平均標準差在 N 軸為 3.81mm，E 軸為 5.18mm。水平速度場模型方面以內插法中的線性及三次樣條內插法建立之模型有最好的精度，另外透過變形模型可以有效將地震之同震位移對坐標預測之影響消除，使速度模型之使用年限得以延長。 / National coordinate system is the foundation of surveying engineering, the establishment and the selection of geodetic datum would directly impact the accuracy of final result. Plate motion will cause earthquakes, volcanic eruptions and other natural disasters. Plate motion especially non-linear motion can also change the relationship between stations in the reference frame. Therefore, a rational and reliable reference frame is needed to ensure the Euclidean integrity quality. Taiwan is located along the bounding of the Eurasian and the Philippine plate, and is therefore a region of non-rigid motion and therefore will shift and rotate in different directions due to the changing stress field. Taiwan’s current coordinate system TWD97 is built by a fixed single term linear model ITRF94. It is not able to precisely model the non-linear motion of the crustal in the Taiwan region. Therefore, Taiwan needs velocity and deformation model to correct the distortion which caused by the crustal motion. This study used 11 years of Taiwan CORS GPS data to investigate the horizontal velocity field in Taiwan and established the horizontal velocity and deformation model by curve fitting, interpolation and LOWESS method. The horizontal coordinate accuracy of the stations is about 2mm-3mm, the vertical accuracy is about 6mm-10mm, and the average standard deviation of velocity field is 3.81mm in N axis, 5.18mm in E axis. As for velocity model, linear and cubic spline interpolations have better model accuracy. In addition, the deformation model can effectively eliminate the influence of coseismic deformation, so that the velocity model will not lose its utility.