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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Influência do tipo de impelidor sobre o desempenho do reator anaeróbio em batelada seqüencial com biomassa granulada tratando esgoto sintético / Influence of the impeller type on the performance of the anaerobic sequencing batch reactor with granulated biomass treating synthetic wastewater

Michelan, Rogério 10 February 2006 (has links)
Em um reator de fundo redondo e volume útil de 5 L tratando esgoto sintético com carga orgânica de 800 mgDQO.'L POT.-1' com biomassa granulada a influência do tipo de escoamento e velocidade rotacional foi investigada com o uso de cinco impelidores sendo eles turbina e pá de seis pás planas verticais, turbina e pá de seis pás planas inclinadas 45 graus e hélice, comumente aplicados em processos biológicos. Foi também investigada a viabilidade de implementação de tubo de tiragem ao reator em conjunto com os impelidores tipo hélice e tipo pá de pás planas inclinadas alternadamente, com vistas a melhorar a mistura e conseqüente transferência de massa no meio reacional. Os resultados mostram que a alteração do tipo de impelidor e as variações da velocidade rotacional não exerceram influência significativa sobre a estabilidade e desempenho dos sistemas estudados. Entretanto a análise das constantes do modelo cinético de primeira ordem mostrou que a alteração na velocidade rotacional exerceu influência de aumento dos valores das constantes, demonstrando com isto que o aumento da velocidade rotacional melhora a transferência de massa sólido-líquido no meio reacional. A análise das constantes cinéticas também demonstrou que a promoção de escoamento axial em reatores agitados mecanicamente é preferível ao escoamento radial quando comparados os impelidores tipo pá de pás planas verticais e de pás planas inclinadas. A presença do tubo de tiragem demonstrou incrementar significativamente a transferência de massa, através do aumento dos valores numéricos das constantes utilizadas no ajuste do modelo cinético de primeira ordem aos valores experimentais. A potência consumida foi inferior a 1,6.'10 POT.-3' HP/'M POT.3' com rotações abaixo de 200 rpm e os impelidores axiais consumiram 75% a menos de potência do que os radiais / The effect of flow type and rotor speed were investigated in a round-bottom reactor with 5 L useful volume containing granular biomass and treating synthetic wastewater with organic load of 800 mgCOD.'L POT.-1'. Five impellers have been used to this end, namely: turbine and paddle with six-vertical-flat blade, turbine and paddle with six-45 degrees-inclined-flat-blade and helix, commonly used in biological processes. Utilization of a draft tube together with the helix and six-alternately-inclined-flat-blade impellers was also assessed as a means to improve mixing and consequently mass transfer in the reaction medium. Results showed that altering impeller type and variation in rotor speed did not exert significant effect on the stability and performance of the investigated systems. However, analysis of the first order kinetic model constants showed that alteration in rotor speed resulted in increase in the values of the constants, demonstrating that increase in rotor speed improves solid-liquid mass transfer in the reaction medium. Analysis of the kinetic constants also showed that axial flow in mechanically stirred reactors is preferable over radial flow when the vertical flat blade impeller is compared to the inclined flat blade impeller. The presence of the draft tube showed significant improvement in mass transfer, which could be seen by the increase in the values of the constants used in the fit of the first order kinetic model to the experimental values. The power consumed was less than 1.6.'10 POT.-3' HP/'M POT.3' at rotor frequency below 200 rpm and the axial impellers consumed 75% less power than the radial ones
212

Determinação de parâmetros mecânicos para dimensionamento de pavimentos com resíduos de construção e demolição / Determination of mechanical parameters for pavement design with construction and demolition waste

Delongui, Lucas January 2016 (has links)
Os processos de reciclagem e produção de agregados reciclados provenientes de resíduos de construção e demolição (RCD) estão se consolidando no Brasil, mas o seu emprego não ocorre na mesma proporção. A utilização desses em pavimentação, principalmente em camadas de base e sub-base, é considerada mais conveniente que em outras áreas, visto que não necessita de procedimentos avançados de reciclagem e utiliza os mesmos processos construtivos que agregados já consagrados, como britas graduadas. Entretanto, as recomendações normativas existentes remetem à caracterização dos agregados, sendo que as alusões ao seu comportamento mecânico são idênticas às impostas para britas graduadas. Além disso, a literatura existente é limitada frente a outros materiais alternativos, o que implica restrições ao seu emprego. Buscando atenuar essas incertezas, essa pesquisa tem como objetivo analisar o comportamento mecânico de agregados reciclados provenientes de RCD, de modo a identificar suas principais características e fornecer parâmetros de anteprojeto para o dimensionamento de pavimentos que utilizam esse material como camadas de suporte. Para isso, a primeira etapa comportou uma análise dos processos de beneficiamento dos agregados reciclados, de modo a identificar como influem nas suas características, o que foi alcançado concomitantemente a segunda etapa, que consistiu na análise dos agregados por meio de ensaios específicos de caracterização física e química. A terceira e principal etapa baseou-se na análise do comportamento mecânico, que além da determinação em equipamentos convencionais, também utilizou um equipamento triaxial de grande porte que comporta corpos de prova de 25 x 50 cm, permitindo a utilização da distribuição a ser empregada em campo. Essa etapa iniciou pela análise da compactação, realizada com curvas granulométricas e modos de umedecimento distintos, onde os mais promissores foram escolhidos para verificar a influência do método de compactação, sendo ele dinâmico ou vibratório. Após essas determinações, a análise concentrou-se no módulo de resiliência, na resistência ao cisalhamento e na deformação permanente, sendo que as evoluções da deformação permanente foram classificadas segundo a teoria do Shakedown. Os resultados demonstraram que a compactação causa a quebra de agregados, porém essa é menor quando utilizada compactação dinâmica. Os RCD apresentaram bom comportamento em relação deformações elásticas, com módulo de resiliência semelhantes aos apresentados por britas. Dado a diminuição de partículas lamelares causada pela quebra durante o processo de compactação, os valores mais representativos do ângulo de atrito e do intercepto coesivo foram 41° e 60 kPa, respectivamente. As análises das deformações realizadas em multiestágios demonstraram que, se utilizados em pavimentos com baixo de volume de tráfego, para razões de tensões σd / σ3 < 2 e tensões desvio σd ≤ 210 kPa, bases compostas de RCD não vão desenvolver deformações plásticas iniciais excessivas e o material vai responder elasticamente. Além disso, essas bases estão seguras contra falhas de cisalhamento. Em suma, as análises indicam que os RCD podem ser utilizados como materiais para bases e sub-bases de pavimentos de baixo volume de tráfego, dando um destino nobre a uma matéria-prima renovável e facilmente encontrada, que na maioria das vezes é desperdiçada e cuja geração aumenta constantemente. / Construction and Demolition Waste (CDW) recycling processes are consolidating in Brazil, but their use does not occur in the same proportion. The application of such in pavement, especially in base and sub-base layers, it is considered more convenient than in other areas because it does not require advanced recycling procedures and using the same constructive processes which aggregates already established, as graded gravel. However, existing normative recommendations refer to the characterization of the aggregates, and the allusions to their mechanical behavior are identical to those imposed on graded gravel. Moreover, the existing literature is limited compared to other alternative materials, implying restrictions on its use. Seeking to mitigate these uncertainties, this research aims to analyze the mechanical behavior of recycled aggregates from CDW, in order to identify its main characteristics and provide parameters for draft design of pavements that using this material as a support layer. For this, the first step involved an analysis of the aggregates recycling procedures, in order to identify the influence of this process in their characteristics, which were concomitantly reached the second stage consisting in the analysis of aggregate by specific tests of physical and chemistry characterization. The third and main step was based on the analysis of mechanical behavior, which besides determining in conventional equipment also utilized a large triaxial device that carries specimens of 25 x 50 cm, allowing the use of the distribution to be employed in field. This step began by analyzing the compaction performed with gradation curves and distinct modes of moistening, where the most promising were chosen to investigate the influence of compaction method, either dynamic or vibration. After these determinations, the analysis focused on the resilient modulus, shear strength and permanent strain, and the evolution of permanent strain were classified according to the theory of Shakedown. The results showed that compaction causes the aggregates break, but this is less when used dynamic compaction. The CDW had good behavior relative elastic strains, with resilient modulus similar to those presented by gravel. Since the decrease of lamellar particles caused by breakage during the compaction process, the most representative values of the friction angle and cohesive intercept were 41° and 60 kPa, respectively. The analysis of the permanent strain carried out in multistage demonstrated that if used in pavements with low traffic volume, for reasons of stress σd / σ3 < 2 and deviator stress σd ≤ 210 kPa, compound bases CDW will not develop excessive initial plastic strain and the material will respond elastically. In addition, these bases are secure against shear failure. In essence, the analysis indicates that the CDW can be used as materials for bases and sub-bases of low volume traffic floors, giving a noble destiny to a renewable raw material and easily found that most of the time is wasted and whose generation is constantly increasing.
213

K3-regelverket -En studie av inkomna remissvar / The K3-framework -A studie of received responses

JONSSON, FREDRIK, SARIC, ALEN January 2011 (has links)
På redovisningsområdet pågår det ständigt förändringar och under den senaste tiden har stort fokus legat på BFN. Nämnden har sedan 2004 arbetat med det så kallade K-projektet där målet är att ta fram samlade regelverk för företag i olika form och storlek. I denna uppsats ligger fokus på K3-regelverket som huvudsakligen är anpassat för större onoterade aktiebolag samt ekonomiska föreningar. Tanken är att regelverket ska baseras på IFRS for SMEs som är IASBs regelverk för små och medelstora företag. I dagsläget finns inget samlat regelverk för dessa bolag i Sverige för upprättande av årsredovisning. Syftet med K3 är att det ska förenkla redovisningsarbetet och på det sättet minska de administrativa kostnaderna.I slutet av år 2010 skickade BFN ut K3 på remiss till 52 instanser. Av dessa valde 28 att skicka in remissvar av olika omfattning. Vi har behandlat 13 utav dessa eftersom resterande inte varit tillräckligt innehållsrika för att bidra med relevant information till uppsatsen.Syftet med uppsatsen har varit att undersöka och redogöra för vilka huvudargument som de olika instanserna har yttrat i sina remissvar gällande K3-regelverket. Studien är av kvalitativ karaktär med en induktiv ansats där empirin har bestått av de utvalda remissvaren.Instanserna har framfört konstruktiv kritik av olika karaktär. Huvudargumenten har vi delat in i fyra olika kategorier. Dessa har varit användarvänlighet, förhållandet till svenska lagar, förhållandet till IFRS for SMEs samt förhållandet till god redovisningssed. Resultatet av studien visar att en stor majoritet anser att användarvänligheten i K3 är undermålig och att strukturen måste förbättras för att kunna tillämpas i praktiken. Flera instanser menar även att BFN i sitt arbete att utforma K3 tagit sig stora friheter att inskränka på regler som anges i ÅRL. I vissa fall har instanser yttrat att normerna i K3 strider mot regeringsformen och ifrågasatt BFNs skrivelser. Positivt ser instanserna dock på att nämnden valt att basera K3 på IFRS for SMEs men att det i flera fall sker avvikelser från det internationella regelverket vilket inte välkomnas av ett antal instanser. Vår slutsats är att K3 i dagsläget inte är tillräckligt välutvecklat för att kunna tillämpas i praktiken eftersom majoriteten av instanserna har sammantaget fler negativa än positiva synpunkter kring regelverket. / Program: Civilekonomprogrammet
214

Právní dopady fúzí akciových společností / Legal Impacts of Mergers of Joint-stock Companies

Večeřová, Stanislava January 2011 (has links)
The aim of this diploma thesis is to analyze various legal aspects related to mergers of public limited liability companies. The thesis begins with a summary of relevant legislation from Czech and European jurisdiction regulating domestic and cross-border mergers. It continues with the procedure of merger and the overview of necessary documentation and requirements. Broad part of the work is related to the impact on diverse areas, such as the impact on shareholders, employees or bookkeeping. The system of merger control is defined within the scope of the chapter dealing with effects on competition law. The legal aspects are illustrated on a practical case in the end of the thesis.
215

A organizaÃÃo do tempo e espaÃo na proposta curricular no Curso de EdificaÃÃes do IFPA / The organization of time and space in motion in curriculum course of buildings IFPA

Marilene Ferreira do Nascimento 09 July 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O presente trabalho à o resultado da pesquisa de mestrado em EducaÃÃo na linha de Movimentos Sociais, e tem como tema a organizaÃÃo do tempo e espaÃo na proposta curricular no Curso de EdificaÃÃes do IFPA (Instituto Federal do ParÃ). Objetiva analisar a relaÃÃo entre tempo e espaÃo no currÃculo prescrito e em aÃÃo do Curso de EdificaÃÃes do PROEJA (Programa Nacional de IntegraÃÃo da EducaÃÃo Profissional com a EducaÃÃo BÃsica, na modalidade EJA), ofertado pelo IFPA. Dessa forma, visa identificar as concepÃÃes e princÃpios que contemplam as novas formas de organizaÃÃo curricular do PROEJA; as relaÃÃes de tempo e espaÃo no desenvolvimento do currÃculo; e as metodologias que atendem Ãs necessidades dos alunos em relaÃÃo ao tempo e espaÃo no PROEJA. Trata de uma pesquisa de abordagem metodolÃgica qualitativa, em que foi realizado um levantamento bibliogrÃfico sobre o tema, a fim de embasar os fundamentos teÃricos que envolvem o problema. Apresenta uma anÃlise e reflexÃo dos documentos oficiais acerca da temÃtica. Paralelamente, discute os resultados obtidos a partir de questionÃrios aplicados aos alunos e professores que fazem parte do curso pesquisado. Caracteriza os sujeitos nos aspectos pessoais e nÃvel de conhecimento sobre o programa. Aborda o desenvolvimento do grupo focal, primeiramente com alunos, e em seguida com os professores que dialogaram sobre o tema, estimulados a falar de suas experiÃncias envolvendo a escola. Verifica que a aproximaÃÃo dos participantes permitiu uma melhor interaÃÃo, o que favoreceu a troca de informaÃÃes. Utiliza como base teÃrica e documental os estudos de Arroyo, Lima, Dante Henrique Moura, Maria Ciavatta, Frigotto e Freire, bem como o Projeto PedagÃgico do curso de EdificaÃÃes do IFPA para o PROEJA e demais documentos oficiais que dÃo base ao programa. Como resultado da anÃlise dos documentos e planos de curso do PROEJA realizados neste trabalho, destaca que a concepÃÃo de integraÃÃo a partir do eixo CiÃncia, Cultura, Trabalho e Tecnologia estÃo mais prÃximoa das aÃÃes dos sujeitos, professores, alunos, gestores do que a concepÃÃo de integraÃÃo entre os conhecimentos, conforme sugere o Documento Base do PROEJA. Conclui que, nos planos de curso e em suas diretrizes, nÃo hà manifestaÃÃo de integraÃÃo entre as disciplinas de forma a criar novos conhecimentos ou conhecimentos integrados que ultrapassem na organizaÃÃo disciplinar a hierarquizaÃÃo dos conteÃdos. O que se encontra nas prescriÃÃes curriculares sÃo previsÃes de que a integraÃÃo deverà ocorrer a partir de um diÃlogo entre as disciplinas e pela troca de experiÃncias entre os professores. Revela, por fim, a materializaÃÃo do conceito de integraÃÃo em aÃÃes individuais e metodolÃgica, muito distante da discussÃo necessÃria à quebra das barreiras entre as diferentes Ãreas e professores das diferentes disciplinas e as possibilidades de integraÃÃo entre os diferentes teÃricos. / This dissertation is the result of a research for Masters in Education in the line of social movements, and has as its theme the organization of time and space in the draft curriculum of the course of Buildings of IFPA. It aims to analyze the relationship between time and space in the curriculum in action of the course of Buildings of the PROEJA (Programa Nacional de IntegraÃÃo da EducaÃÃo Profissional com a EducaÃÃo BÃsica, in the form EJA), offered by IFPA. It aims to identify the concepts and principles that addresses the new forms of organization of the curriculum PROEJA; to identify the relationships between time and space in curriculum development; and also to identify the methodologies that meet the needs of students over time and space in PROEJA. Uses a qualitative methodological approach, in which it was based on a literature on the subject, with the purpose of the theoretical basis involving the problem. Presents a reflection and analysis of official documents on the subject. Parallel to the second step, applies questionnaires to students and teachers who are part of the course in focus. At this phase, it objectives to characterize the subjects in the personal aspects and level of knowledge about the program. Approaches the development focus group, at first with students and then with teachers who conversed on the subject, encouraged to talk about their experiences involving the school. Verifies that the approachment allowed to the participants a better interaction, favoring the exchange of information. Uses as theoretical and documentary support the studies of Arroyo, Lima, Dante Henrique Moura, Maria Ciavatta, Frigotto and Freire; also the Educational Project of the course of Buildings of IFPA for PROEJA and other official documents that underlie the program. As a result of the analysis of documents and plans to travel PROEJA performed in this work, emphasizes that the concept of integration from the axis Science, Culture, Work and Technology are closer to the actions of individuals, teachers, students, managers who design integration of knowledge, as suggested by the Base Document PROEJA. Concludes that in the course plans and their policies there is no manifestation of integration across disciplines to create new knowledge or knowledge embedded in the organization beyond the disciplinary hierarchy of content. What is found in the curricular requirements are forecasts that integration should occur from a dialogue between the disciplines and the exchange of experiences among teachers. Reveals, at last, that the materialization of the concept of integration in individual stocks and methodological far the discussion needed to break the barriers between different areas and teachers from different disciplines and the possibilities of integration between the different theorists.
216

Lobbing - ekonomické a právní aspekty : Postoje členů akademické právnické obce a zákonodárného sboru dolní komory Parlamentu České republiky k regulaci lobbingu / Lobbying - economic and legal aspects : attitudes of members of the law academia and members of the lower house of the Parliament of the Czech Republic to the regulation of lobbying

Blažek, Matej January 2018 (has links)
Lobbying - Economic and Legal aspects Abstract The diploma thesis deals with lobbying and its economic and legal aspects. The aim of the thesis is to present lobbying from a broad perspective in the context of other regulations by using descriptive, comparative and analytical methods and to provide a comprehensive overview of the development of efforts to regulate lobbying in the Czech Republic. Particular attention is paid to the analysis of the last governmental regulatory initiative where I am testing a hypothesis of whether the underway regulation is systemically correct in light of examples in other countries. I also conducted two surveys aimed at finding out the attitudes of members of the law academia and members of the lower house of the Parliament of the Czech Republic to the regulation of lobbying in the Czech Republic. The data serve both to (i) illustrate the interpretation of lobbying across the work, (ii) but also because of the specific proposed variant of lobbying within the framework of the approved substantive intent of the lobbying law (the deadline for submitting a paragraph to the government is set to end 2018), and (iii) I believe that they can be useful even when finalizing the bill, or other later proposed measures under the de lege ferenda considerations on lobbying. The thesis is...
217

To Forgive or Not to Forgive? A Reappraisal of Vietnam War Evaders and Deserters in President Gerald Ford's Clemency Program

Carver, Courtney 06 August 2018 (has links)
In 1974, President Ford began the arduous task of healing the wounds sustained by the United States during the Vietnam War. His controversial clemency plan gave those who had either deserted the military or those who evaded the draft the chance to earn their way back into American society. President Ford was willing to face this opposition to move the country closer to resolving an issue that was tearing the nation apart. In the applications to Ford’s Presidential Clemency Board, thousands of deserters and evaders reveal their motivations, and in doing so present a large body of evidence that contradicts the usual perception of the Vietnam “draft-dodger” and deserter. In the transition between the hardline anti-clemency position of President Nixon, and the full clemency position of President Carter, Ford took strong measures to achieve resolution, and the evidence herein could suggest a reappraisal of the Ford presidency.
218

Osídlení v Telči v 18. století na základě pramenů městské a katastrální provenience / Population in the town of Telč in 18th century, based on sources of town and cadastral provenance

MAREČEK, Jakub January 2019 (has links)
This diploma thesis deals with population in the town of Telč in 18th century, based on sources of town and cadastral provenance. The issue is of particular interest as it has not been researched in greater detail yet. At first, the thesis provides an introduction to the extant literature covering the history of Telč, assessing the authors' approach, what historical epoch they consider most prosperous and their perspective of the town in 18th century. Chapter II addresses sources of town and cadastral provenance, thus introducing and evaluating the sources the thesis is based on. Chapter III addresses the regulated municipal authority in Telč. Chapter IV provides an insight into the development of town population in the Bohemian lands in 17th and 18th centuries, which enables contextualizing Telč within the development. Chapter V is dedicated to the town itself, focusing on its history in the relevant period, the town's inhabitants, external description, the Inner Town and eventually, the social pattern of the inhabitants. The social pattern is described in a detailed analysis of three houses located on the town square and their owners. In the end I will describe property structure of the town councillors who were serving in office in 1762, 1766, 1768 and 1770.
219

Meteorologically adjusted trends of ozone and dispersion of air pollutants in the Hsuehshan Tunnel

Li, Han-chieh 22 June 2010 (has links)
This study separated two parts: PART ¢¹ Meteorologically adjusted trends of ozone Since meteorological changes strongly affect ambient ozone concentrations, trends in concentrations of ozone upon the adjustment of meteorological variations are important of evaluating emission reduction efforts. This work is to study meteorological effects on the long-term trends of ozone concentration using a multi-variable additive model in Kaohsiung. The long-term trends of ozone concentration were analyzed using the Holland model (without meteorological-adjusted) and the robust MM Regression model (with meteorological-adjusted) based on the data of eight EPA air quality stations from 1997 to 2006 in Kaohsiung area. According to the result of the simulation, the simulated value of the robust MM-Regression model present more valid than the Holland model.The simulated results show that the long-term ozone concentration increases at 13.84% (or 13.06%) monthly (or annually) after meteorological adjustments, less than at 26.10% (or 23.80%) without meteorological adjustments in Kaohsiung county. The simulated results show that the long-term ozone concentration increases at 9.01% (or 6.88%) monthly (or annually) after meteorological adjustments, less than at 22.01% (or 19.67%) without meteorological adjustments in Kaohsiung city. Wind speed, duration of sunshine and pressure are the three dominant factors that influence the ground-level ozone levels in Kaohsiung area. PART ¢º Dispersion of air pollutants in the Hsuehshan Tunnel Concentrations of carbon monoxide (CO) and nitrogen oxides (NOx) were measured from November 14 ¡V 17 2008 in a cross-mountain Hsuehshan traffic tunnel stretching 12.9 km and containing eastward and westward channels. Air pollutants of CO (carbon monoxide) and NOx (nitrogen oxides) will be monitored at the inlet, outlet and vertical shafts of the tunnel. Meanwhile, numerical simulation of three-dimensional turbulent flow will be performed using STAR-CD software. Traffic and pollutant concentrations during the weekends exceeded those during the weekdays. Measured concentrations of CO at the two tunnel outlets (14.5 ¡V 22.8 ppm) were approximately three times higher than those at the two tunnel inlets (3.2 ¡V 7.3 ppm), while concentrations of NOx at the two tunnel outlets (1.9 ¡V 2.9 ppm) were approximately four to five times higher than those at the two tunnel inlets (0.3 ¡V 0.8 ppm). The outlet of vertical draft 2 had the highest pollutant concentrations (CO = 12.3 ppm; NOx = 1.9 ppm), followed by vertical drafts 1 and 3. Three-dimensional turbulence modeling results indicate that airflow in the tunnel was primarily driven by the combined effects of axial fans and vehicles. Results of this study demonstrate that simulated pollutant concentrations increase downstream and are vertically stratified, due to tailpipe exhausts close to tunnel floor. Simulations agreed fairly well with measurements.
220

Fiabilité et évaluation des incertitudes pour la simulation numérique de la turbulence : application aux machines hydrauliques / Reliability and uncertainty assessment for the numerical simulation of turbulence : application to hydraulic machines

Brugière, Olivier 14 January 2015 (has links)
La simulation numérique fiable des performances de turbines hydrauliques suppose : i) de pouvoir inclure dans les calculs RANS (Reynolds-Averaged Navier-Stokes) traditionnellement mis en œuvre l'effet des incertitudes qui existent en pratique sur les conditions d'entrée de l'écoulement; ii) de pouvoir faire appel à une stratégie de type SGE (Simulation des Grandes Echelles) pour améliorer la description des effets de la turbulence lorsque des écarts subsistent entre calculs RANS et résultats d'essai de référence même après prise en compte des incertitudes. Les présents travaux mettent en oeuvre une démarche non intrusive de quantification d'incertitude (NISP pour Non-Intrusive Spectral Projection) pour deux configurations d'intérêt pratique : un distributeur de turbine Francis avec débit et angle d'entrée incertains et un aspirateur de turbine bulbe avec conditions d'entrée (profils de vitesse,en particulier en proche paroi, et grandeurs turbulentes) incertaines. L'approche NISP est utilisée non seulement pour estimer la valeur moyenne et la variance de quantités d'intérêt mais également pour disposer d'une analyse de la variance qui permet d'identifier les incertitudes les plus influentes. Les simulations RANS, vérifiées par une démarche de convergence en maillage, ne permettent pas pour la plupart des configurations analysées d'expliquer les écarts calcul / expérience grâce à la prise en compte des incertitudes d'entrée.Nous mettons donc également en ouvre des simulations SGE en faisant appel à une stratégie originale d'évaluation de la qualité des maillages utilisés dans le cadre d'une démarche de vérification des calculs SGE. Pour une majorité des configurations analysées, la combinaison d'une stratégie SGE et d'une démarche de quantification des incertitudes permet de produire des résultats numériques fiables. La prise en compte des incertitudes d'entrée permet également de proposer une démarche d'optimisation robuste du distributeur de turbine Francis étudié. / The reliable numerical simulation of hydraulic turbines performance requires : i) to includeinto the conventional RANS computations the effect of the uncertainties existing in practiceon the inflow conditions; ii) to rely on a LES (Large Eddy Simulation) strategy to improve thedescription of turbulence effects when discrepancies between RANS computations and experimentskeep arising even though uncertainties are taken into account. The present workapplies a non-intrusive Uncertainty Quantification strategy (NISP for Non-Intrusive SpectralProjection) to two configurations of practical interest : a Francis turbine distributor, with uncertaininlet flow rate and angle, and a draft-tube of a bulb-type turbine with uncertain inflowconditions (velocity distributions, in particular close to the wall boundaries, and turbulentquantities). The NISP method is not only used to compute the mean value and variance ofquantities of interest, it is also applied to perform an analysis of the variance and identify inthis way the most influential uncertainties. The RANS simulations, verified through a gridconvergence approach, are such the discrepancies between computation and experimentcannot be explained by taking into account the inflow uncertainties for most of the configurationsunder study. Therefore, LES simulations are also performed and these simulations areverified using an original methodology for assessing the quality of the computational grids(since the grid-convergence concept is not relevant for LES). For most of the flows understudy, combining a SGE strategy with a UQ approach yields reliable numerical results. Takinginto account inflow uncertainties also allows to propose a robust optimization strategy forthe Francis turbine distributor under study.

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