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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.
111

Vibrační spektroskopie ve farmaceutické analýze / Vibrational spectroscopy in pharmaceutical analysis

Průchová, Kristýna January 2012 (has links)
The aim of this diploma thesis is the application of vibrational spectroscopy in pharmaceutical analysis in studying solid pharmaceutical forms. The surface of tablet samples containing the active substance from the group of statins has been studied especially by the methods infrared microscopy. Spectral maps of samples were collected thanks to the techniques of specular reflection, attenuated total reflection (ATR) and "inverse" ATR after determining optimal conditions for measurements. In order to evaluate these measured maps, one-dimensional analysis and principal component analysis were used. As the same samples of tablets were also measured by Raman microscopy, the comparison has been provided. The measured distribution maps enable both a determination of substances in the sample and conclusion concerned a method of tablets' preparation. The method in this case is a granulation, which has been found out from a comparison of maps of generic and original medicament. The specular reflection method was selected to be the most appropriate technique for obtaining the maps of the surface of a tablet, via confrontation of particular methods consequently with consideration of their advantages and disadvantages in the measurement and data processing.
112

Perspectiva histórica e tecnológica da calibração do túnel 2 do Sistema Cantareira de adução de água para a região metropolitana de São Paulo / Historical and technological perspective of the test for the calibration of tunnel 2 of the Cantareira water project for the metropolitan area of São Paulo

Pinheiro, Hemerson Donizete 22 March 2007 (has links)
Trabalhos de cunho historiográfco que visam resgatar a produção científica e tecnológica de um país tem auxiliado a compreender e a classificar seu nível de desenvolvimento frente a estas questões. Com este trabalho, espera-se dar início no Departamento de Hidráulica e Saneamento (SHS) da Escola de Engenharia de São Carlos, a um levantamento historiográfico da produção tecnológica e científica de seus pós-graduandos e professores. Para tanto, resgata-se um trabalho realizado entre o final da década de 1960 e início da década de 1970, pela Cátedra de Mecânica dos Fluidos (precursora do SHS), que teve como objetivo prever a vazão de água do túnel 2 do Sistema Cantareira de abastecimento de água para a região metropolitana de São Paulo. Nesta galeria foi realizado um ensaio original com circulação de ar, para o qual foram desenvolvidos métodos e técnicas a fim de verificar a vazão e auxiliar no seu dimensionamento, para garantir uma adução de 33 \'M POT.3\'/s. Mediante o levantamento, organização cronológica e análise dos documentos produzidos pelos autores do referido ensaio, resgatam-se as influências teóricas que nortearam as metodologias, as técnicas e tecnologias e analisam-se, de acordo com os registros documentais, a execução e resultados alcançados pelos ensaios. / Works that have as objective to review the scientific and technological production of a country have helped to understand and to measure its level of development regarding these questions. With this work, hopefully a historical survey of the technological and scientific production of its graduate students and teachers begins at the Departamento de Hidráulica e Saneamento (SHS) at the Escola de Engenharia de São Carlos. In this way, a work that was carried out between the end of the 1960\'s and beginning of the 1970\'s, by the chair of fluid mechanics (precursor of the SHS), which had as objective to foresee the water flow rate at tunnel 2 of the Cantareira water project for the metropolitan area of São Paulo. An original test using air circulation was carried out in the tunnel. Methods and techniques were developed in order to verify the flow rate and check its size, to guarantee 33 \'M POT.3\'/s of flow. The documents produced by the authors of the test were surveyed, organized chronologically and analyzed, seeking to infer the theoretical influences that had guided the methodologies, to describe the techniques and technologies and to analyze, in accordance with the document registers, the execution and results reached from the tests.
113

A sombra dos leviatãs: um estudo crítico dos desencontros entre as faces amistosa e crispada do Estado sob as globalizações e as guerras do século XXI / The shadow of leviathans A critical study about the failures between the friendly and withdrawn faces of the State in Twenty-First Century Globalizations and Wars

Espinosa, Antonio Roberto 27 June 2011 (has links)
Um conjunto de reflexões teóricas sobre as incompatibilidades entre a Ordem Inter-nacional pós-Guerra Fria e as categorias estruturantes dos paradigmas analíticos dominantes, esta tese procura também apontar dados empíricos e listar questões a serem compreendidas por um novo modo de produção de conhecimentos em rela-ções internacionais. Ela critica tanto os paradigmas unidimensionais, principalmente os de corte liberal e leno-stalinistas, quanto os bidimensionais, de inspiração realista e racionalista, indicando que ambos formam redes conceituais baseadas numa dialé-tica dicotômica, que reduz a complexidade do internacional e do estrangeiro a um olhar e interesse nacionais. Sugere que o sistema internacional e os subsistemas regionais, como objetos de estudo, não se reduzem a suas unidades, constituindo uma terceira dimensão, ou zona cinzenta, cuja conformação, para ser compreendida depende da análise integrada dos fenômenos da guerra, das globalizações e do for-talecimento do Estado. Completando as sugestões para o debate e a formulação de conceitos interpretativos mais abrangentes, além de alguns neologismos, esta tese constrói algumas tipologias compreensivas. O autor adverte, contudo, que essas formulações têm o propósito de ilustrar a análise, não de fechar a discussão com um modelo acabado. / A set of theoretical reflections on the contradictions between the post-Cold War inter-national order and the structuring categories of the prevailing analytical paradigms, this thesis also tries to point to empirical data and list questions to be understood by a new way of producing knowledge in international relations. It criticizes both one-dimensional paradigms, mainly those in the liberal and Lenin-Stalinist model, and two-dimensional paradigms of realistic and rational inspiration, showing that both of them build conceptual networks based on the dialectics of dichotomy, which reduces the complexity of being international and foreign to a national vision and interest. The work also suggests that the international system and the regional subsystems, as objects of study, are not limited to their units, making up a third dimension, or grey zone, whose configuration can only be understood through an integrated analysis of the war phenomena, globalization and the strengthening of the State. By making suggestions for the debate and formulation of more comprehensive interpretation concepts, in addition to some neologisms, this thesis builds some broad typologies. However, the author warns that these formulations have the purpose of illustrating the analysis, not closing the debate on a finished model.
114

Gênero digital homepage em educação online: uma análise sociorretórica bidimensional / Digital genre homepage in online education: a two-dimensional sociorhetorical analysis

Campos, Karlene do Socorro da Rocha 03 June 2014 (has links)
Made available in DSpace on 2016-04-28T19:33:48Z (GMT). No. of bitstreams: 1 Karlene do Socorro da Rocha Campos.pdf: 10725568 bytes, checksum: 10f11e3686df42cbc9257674a1e09cfb (MD5) Previous issue date: 2014-06-03 / This research is inserted in the fields of Linguistics and Distance Education, specifically of Online Education. It comprises the study of digital genre homepage on subjects of the graduation course Mathematics Teaching Education - Distance Mode offered by the Pontifical Catholic University of São Paulo (PUC-SP). We are based mainly on sociorhetorical conception of textual genre, in which genre is conceived as a pragmatic entity. In relation to this entity, the notions of purpose, context and action are interlinked. From this perspective, to produce a genre, users aim to achieve a certain purpose, and the success of the action that the genre conveys depends on the language choices appropriate to the communicative situation. Our hypothesis is that knowledge of the sociorhetorical organization of homepage genre helps the instructional designer in the development of educational activities that promote a positive interaction between participants of online distance learning courses and pedagogical contents, and consequently promote their involvement in the teaching and learning process. In order to test it, we examined this organization in homepages of courses offered in the 2nd half of 2012, considering the twodimensional analysis of genre model (ASKEHAVE; NIELSEN, 2004), that is founded on the sociorhetorical analysis proposed by Swales (1990), and that consider in the reading and navigating modes of digital genres, communicative purposes; functional units (rhetorical movements and links); and rhetorical strategies employed to achieve the communicative purpose. Primarily, we are based on studies of genre as social action (MILLER, 2009, 2009a [1984], 2009b [1992]; BAZERMAN, 2006 [1997]; 2009a [2004], 2009b [1994]; SWALES, 1990; BHATIA, 1993), as well as on studies of digital text genre (MARCUSCHI, 2010 [2004]; ASKEHAVE; NIELSEN, 2004) and hypertext (LEMKE, 2002; FINNEMANN, 1999). This thesis is a case study based on observation and description of a phenomenon in a specific context (MARTINS, 2008 [2006]; YIN, 1984; 2005 [2003]; TRIVIÑOS, 1987). The results obtained show that the knowledge of sociorhetorical organization of homepage genre provides an organization of pedagogical contents more oriented to interests and needs of users. Consequently, this knowledge contributes to the student engagement with the educational process / Esta pesquisa insere-se nos campos da Linguística e da Educação a Distância, mais especificamente da Educação Online, e consiste no estudo do gênero textual digital homepage em disciplinas do curso Matemática Licenciatura Modalidade a distância, oferecido pela Pontifícia Universidade Católica de São Paulo (PUC-SP). Embasamo-nos, principalmente, na concepção sociorretórica de gênero textual, em que o gênero é concebido como uma entidade pragmática, na qual se entrelaçam as noções de propósito, contexto e ação. Nessa ótica, ao produzirem um gênero, os usuários visam a atingir um determinado propósito, e o sucesso da ação que o gênero veicula depende das escolhas linguísticas adequadas à situação comunicativa. Nossa hipótese é que o conhecimento da organização sociorretórica do gênero homepage auxilia o designer instrucional a promover uma interação positiva dos participantes de cursos online a distância com o conteúdo pedagógico e, consequentemente, a promover o seu envolvimento com o processo de ensino e aprendizagem. Para testá-la, examinamos essa organização nas homepages de disciplinas oferecidas no 2º semestre de 2012, na perspectiva do modelo de análise bidimensional de gêneros (ASKEHAVE; NIELSEN, 2004), que parte da análise sociorretórica proposta por Swales (1990) e considera, nos modos de leitura e navegação dos gêneros digitais, os propósitos comunicativos; as unidades funcionais que os caracterizam (movimentos retóricos e links); as estratégias retóricas empregadas para o alcance dos propósitos comunicativos. Pautamo-nos, principalmente, em estudos de gênero como ação social (MILLER, 2009, 2009a [1984], 2009b [1992]; BAZERMAN, 2006 [1997]; 2009a [2004]; 2009b [1994]; SWALES, 1990; BHATIA, 1993); de gênero textual digital (MARCUSCHI, 2010 [2004]; ASKEHAVE; NIELSEN, 2004) e de hipertexto (LEMKE, 2002; FINNEMANN, 1999). O presente trabalho é um estudo de caso, fundado na observação e descrição de um fenômeno em contexto específico (MARTINS, 2008 [2006]; YIN, 1984; 2005 [2003]; TRIVIÑOS, 1987). Os resultados obtidos demonstram que conhecer a organização sociorretórica do gênero homepage propicia a organização de conteúdo pedagógico mais voltada aos interesses e às necessidades dos usuários. Por conseguinte, contribui para o envolvimento do aluno com o processo educacional
115

Synthesis of Aluminum-Titanium Carbide Nanocomposites by the Rotating Impeller Gas-Liquid In-situ Method

Anza, Inigo 06 September 2016 (has links)
"The next generation of aluminum alloys will have to operate at temperatures approaching 300°C. Traditional aluminum alloys cannot perform at these temperatures, but aluminum alloys reinforced with fine ceramic particles can. The objective of this research is to develop a process to synthesize Al-TiC composites by the Rotating Impeller Gas-Liquid In-situ method. This method relies on injecting methane into molten aluminum that has been pre-alloyed with titanium. The gas is introduced by means of a rotating impeller into the molten alloy, and under the correct conditions of temperature, gas flow, and rotation speed, it reacts preferentially with titanium to form titanium carbide particles. The design of the apparatus, the multi-physics phenomena underlying the mechanism responsible for particle formation and size control, and the operation window for the process are first elucidated. Then a parametric study that leads to the synthesis of aluminum reinforced with TiC microparticles and nanoparticles is described. Finally, potential technical obstacles that may stand in the way of commercializing the process are discussed and ways to overcome them are proposed. "
116

Characterization and improvement of a surface aerator for water treatment / Caractérisation et amélioration d’un aérateur de surface pour le traitement des eaux

Issa, Hayder Mohammed 24 October 2013 (has links)
Un nouveau système d’aération de surface pour le traitement des eaux usées a été étudié. Sa spécificité réside dans sa capacité à fonctionner selon deux modes : aération ou simple brassage, en modifiant uniquement le sens de rotation du système. Un pilote a permis de cibler le travail sur l’étude expérimentale du transfert de matière et de l’hydrodynamique. Les champs d'écoulement et les mesures de vitesse à l'intérieur de la cuve agitée ont été réalisés par vélocimétrie laser à effet Doppler (LDV) et par vélocimétrie par images des particules (PIV) pour le mode monophasique (brassage) et pour le mode diphasique (aération). Le transfert d'oxygène se produit à la fois dans la cuve et dans le spray au-dessus de la surface de l'eau. Il a été étudié dans les deux zones. Différentes configurations et conditions opératoires ont été testées afin de comprendre les phénomènes d’interaction : tube de guidage, hélice complémentaire RTP, vitesse de rotation, niveau de submersion des pales de la turbine. La partie expérimentale sur l’hydrodynamique et les champs d'écoulement montre que le mode de fonctionnement en pompage vers le bas (brassage) avec tube de guidage procure les meilleurs résultats en termes de mélange si on se réfère aux champs d'écoulement et à la mesure du temps de mélange. Pour le mode de fonctionnement en pompage vers le haut (aération), les résultats expérimentaux montrent que la configuration du système complet est la plus efficace si on considère le transfert d’oxygène, les vitesses moyennes, l'intensité de l'écoulement turbulent et le temps de mélange. Il est constaté que la meilleure efficacité d'aération standard est atteinte (SAEb = 2.65 kgO2kw-1h-1) lorsque le système complet est utilisé. L'efficacité d'aération standard à 20°C la plus élevée au niveau du spray d'eau est obtenue ((ESP)20 = 51,3%) avec la configuration du système complet. Plusieurs modèles sont proposés pour calculer le transfert d'oxygène dans la cuve et dans le spray, la consommation énergique et le temps de mélange. Ces relations permettent d’évaluer l’influence des différents paramètres géométriques et de fonctionnement dans des systèmes similaires à une échelle industrielle. / A new surface aeration system for water and wastewater treatment has been studied. Its uniqueness lies in its ability to operate in two modes: aeration or simply blending (mixing) by just reversing the direction of rotation. An experimental plant has enabled to focus on mass transfer performance and hydrodynamics. The flow pattern and the velocity field measurements inside the agitated tank were performed by both the Laser Doppler Velocimetry (LDV) and the Particle Image Velocimetry (PIV) techniques for the single phase (Mixing) mode and for the two phases (Aeration) mode. The oxygen mass transfer occurs both in the water bulk and in the spray above water surface and has been independently investigated. Different configurations and operational conditions were tested during the experimental part in order to interpret phenomenon effect of the draft tube and RTP propeller, rotational speed, turbine blades submergence and else on the flow field and the oxygen mass transfer in the agitated system that produced mainly by a cone shape turbine. The experimental part dealing with hydrodynamics and flow field shows that the down-pumping operation mode with the draft tube has the most convenient results in the mixing mode with respect to turbulent flow field and mixing time. Whilst for the up-pumping aeration mode the hydrodynamics experimental results show the whole system configuration is the most convenient with regarded to mean velocities, turbulent flow intensity and mixing time. For the oxygen mass transfer experimental part, it is found that the highest standard liquid bulk aeration efficiency is achieved (SAEb = 2.65 kgO2 kw-1h-1) when the whole system configuration is used. The highest standard aeration efficiency at 20°C for the water spray zone is accomplished ((Esp)20 = 51.3 %) with the whole system configuration. Several correlations models have been derived for the oxygen mass transfer in water bulk and spray zones, power consumption and mixing time, on the basis of experimental results. They can be used as tools to estimate these parameters for geometrical and dynamical similar systems at industrial scales.
117

Génération de modèles analytiques pour la conception préliminaire de systèmes multi-physiques : application à la thermique des actionneurs et des systèmes électriques embarqués / Analytical model generation for the preliminary design of multi-physical systems : application to the thermal modelling of actuators and embedded electrical systems

Sanchez, Florian 19 June 2017 (has links)
L'objectif de cette thèse est de fournir des méthodes et outils numériques dédiés à la conception préliminaire de systèmes multi-physiques, avec une attention particulière quant à l'évaluation des transferts thermiques mis en jeu dans les actionneurs et les systèmes électriques embarqués. Ce besoin émane de la recherche industrielle actuelle menant au développement de l'avion plus électrique ("More Electrical Aircraft " - MEA), qui met en œuvre de nouvelles technologies de systèmes embarqués où la gestion thermique de tels dispositifs est primordiale. Dans un premier temps, cette thèse propose une méthodologie basée sur l'analyse dimensionnelle et les modèles de substitution pour générer des modèles analytiques à partir de simulations éléments finis. De plus, une méthodologie de génération de plans d'expériences optimaux adaptée à l'utilisation du formalisme adimensionnel est également proposée. Dans un deuxième temps, deux approches numériques permettant de réduire le nombre de variables adimensionnelles d'un problème et d'étudier leur significativité physique sont proposées. La première approche utilise l'analyse de sensibilité d'une façon originale pour mettre en avant la significativité des nombres adimensionnels du problème considéré. La deuxième approche fait appel à des algorithmes d'optimisation pour réduire le nombre de variables adimensionnelles d'un problème. Enfin, les méthodes proposées ont été appliquées avec succès pour modéliser les composants d'un actionneur électromécanique d'aileron (moteur électrique de type brushless, carter mécanique), et d'un convertisseur de puissance électrique (condensateur, inductance, dissipateur) utilisé dans le contexte aéronautique. / The objective of this thesis is to develop methods and tools dedicated to the preliminary design of multi-physical systems, with a particular attention to the thermal modelling of actuators and embedded electrical systems. This need arises from the current industrial research which led to the More Electrical Aircraft program (MEA), which deals with new technologies of embedded systems where the thermal management of such devices is essential. First of all, this thesis proposes a methodology based on dimensional analysis and surrogate modelling technique to generate analytical models from finite element simulations. Furthermore, a methodology for constructing optimal design of experiments intended for building surrogate models using dimensionless variables is also proposed. Finaly, two numerical approaches which enable to reduce the number of dimensionless variables of a problem and to study their physical significance are proposed. The first approach uses sensitivity analysis in an original way to highlight the physical significance of the dimensionless numbers for a considered problem. The second approach uses optimization algorithms to reduce the number of dimensionless variables. In the second part of the thesis, the proposed methods were successfully applied to model several components of an electromechanical actuator (EMA) of an aileron (electrical brushless motor, mechanical housing, etc.), and of a power converter (capacitor, inductance, heatsink) used in an aeronautical context.
118

Avaliação experimental do desgaste de canto durante o processo de eletroerosão do AISI H13

Campos, José Alexandre de 19 December 2014 (has links)
A fabricação de moldes e matrizes são ricas em detalhes e geometrias complexas, exigindo tecnologias mais inovadoras e precisas. Um dos processos que se destaca na fabricação de moldes e matrizes, é o de eletroerosão por penetração (Electrical Discharge Machining - EDM). A usinagem por descargas elétricas é classificada como um processo de fabricação de geometria não definida, onde a remoção de material é realizada por repetidas descargas elétricas entre dois eletrodos eletricamente condutores. O desgaste da ferramenta é um dos principais parâmetros de medida no desempenho da usinagem por EDM. O maior problema ocasionado pelo desgaste de canto do eletrodo é a mudança de geometria da ferramenta no decorrer da usinagem, alterando a tolerância geométrica e o dimensional da cavidade. O presente trabalho propõe avaliação dimensional do desgaste de canto do eletrodo, no decorrer da usinagem do processo de EDM, variando o ângulo de superfície frontal do eletrodo. Outro propósito é a criação de um índice, chamado de taxa de arredondamento, que leva em consideração as áreas de desgaste de canto do eletrodo em função da área removida de material da peça. Os resultados mostraram que os eletrodos de cobre, cobre tungstênio e grafite, tem um grande crescimento de raio de canto no inicio da usinagem, estabilizando esses valores com tempo maiores de processo. O ângulo de superfície frontal do eletrodo influência diretamente no desgaste de canto do eletrodo. Os eletrodos de grafite não apresentaram comportamento de arredondamento de desgaste de canto durante os ensaios. Para o índice de taxa de arredondamento os eletrodos de cobre tungstênio tiveram o menor valor apresentado na usinagem do AISI H13. / The manufacture of molds and dies are rich in detail and complex geometries, requiring more innovative and precise technologes. One of the processes that stands out in the manufacture of molds and dies, is to EDM by penetration (Electrical Discharge Machining - EDM). The cutting by electrical discharge is classified as a non-defined geometry manufacturing process where material removal is carried out by repeated electrical discharge between two electrodes electrically conductive. The tool wear is a major measurement parameters in machining performance by EDM. The biggest problem caused by the electrode corner wear is the tool geometry change during the machining by changing the geometric tolerance and dimensional cavity. This paper proposes dimensional evaluation of the electrode corner wear, during the machining of the EDM process, varying the front surface of the electrode angle. Another purpose is to create an index, called rounding rate, which takes into account the areas of electrode corner wear due to the removed area of the workpiece material. The results showed that the copper electrode, copper tungsten and graphite, has a large corner radius growth at the beginning of machining, stabilizing these values with higher process time. The front surface of the electrode angle influence directly on the electrode corner wear. Graphite electrodes showed no corner wear rounding behavior during the tests. For rounding rate index tungsten copper electrodes had the lowest value presented in the machining of AISI H13.
119

Avaliação experimental do desgaste de canto durante o processo de eletroerosão do AISI H13

Campos, José Alexandre de 19 December 2014 (has links)
A fabricação de moldes e matrizes são ricas em detalhes e geometrias complexas, exigindo tecnologias mais inovadoras e precisas. Um dos processos que se destaca na fabricação de moldes e matrizes, é o de eletroerosão por penetração (Electrical Discharge Machining - EDM). A usinagem por descargas elétricas é classificada como um processo de fabricação de geometria não definida, onde a remoção de material é realizada por repetidas descargas elétricas entre dois eletrodos eletricamente condutores. O desgaste da ferramenta é um dos principais parâmetros de medida no desempenho da usinagem por EDM. O maior problema ocasionado pelo desgaste de canto do eletrodo é a mudança de geometria da ferramenta no decorrer da usinagem, alterando a tolerância geométrica e o dimensional da cavidade. O presente trabalho propõe avaliação dimensional do desgaste de canto do eletrodo, no decorrer da usinagem do processo de EDM, variando o ângulo de superfície frontal do eletrodo. Outro propósito é a criação de um índice, chamado de taxa de arredondamento, que leva em consideração as áreas de desgaste de canto do eletrodo em função da área removida de material da peça. Os resultados mostraram que os eletrodos de cobre, cobre tungstênio e grafite, tem um grande crescimento de raio de canto no inicio da usinagem, estabilizando esses valores com tempo maiores de processo. O ângulo de superfície frontal do eletrodo influência diretamente no desgaste de canto do eletrodo. Os eletrodos de grafite não apresentaram comportamento de arredondamento de desgaste de canto durante os ensaios. Para o índice de taxa de arredondamento os eletrodos de cobre tungstênio tiveram o menor valor apresentado na usinagem do AISI H13. / The manufacture of molds and dies are rich in detail and complex geometries, requiring more innovative and precise technologes. One of the processes that stands out in the manufacture of molds and dies, is to EDM by penetration (Electrical Discharge Machining - EDM). The cutting by electrical discharge is classified as a non-defined geometry manufacturing process where material removal is carried out by repeated electrical discharge between two electrodes electrically conductive. The tool wear is a major measurement parameters in machining performance by EDM. The biggest problem caused by the electrode corner wear is the tool geometry change during the machining by changing the geometric tolerance and dimensional cavity. This paper proposes dimensional evaluation of the electrode corner wear, during the machining of the EDM process, varying the front surface of the electrode angle. Another purpose is to create an index, called rounding rate, which takes into account the areas of electrode corner wear due to the removed area of the workpiece material. The results showed that the copper electrode, copper tungsten and graphite, has a large corner radius growth at the beginning of machining, stabilizing these values with higher process time. The front surface of the electrode angle influence directly on the electrode corner wear. Graphite electrodes showed no corner wear rounding behavior during the tests. For rounding rate index tungsten copper electrodes had the lowest value presented in the machining of AISI H13.
120

Compara??o entre planejamento estat?stico experimental e an?lise dimensional em opera??es de mistura e separa??o para sistema ?leo-?gua

Moraes, Norberto Araujo de 30 September 2011 (has links)
Made available in DSpace on 2014-12-17T15:01:52Z (GMT). No. of bitstreams: 1 NorbertoAM_TESE.pdf: 2336588 bytes, checksum: 940ad1b0befe8c431d2e9fb731a885b6 (MD5) Previous issue date: 2011-09-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims to determine a better methodology to help predicting some operational parameters to a new design of mixer-settler on treating wastewater produced by petroleum industry, called MDIF (Misturador-Decantador ? Invers?o de Fases/ Mixer-Settler based on Phase Inversion MSPI). The data from this research were obtained from the wastewater treatment unit, called MSPI-TU, installed on a wastewater treatment plant (WTP) of PETROBRAS/UO-RNCE. The importance in determining the better methodology to predict the results of separation and extraction efficiency of the equipment, contributes significantly to determine the optimum operating variables for the control of the unit. The study was based on a comparison among the experimental efficiency (E) obtained by operating MSPI-TU, the efficiency obtained by experimental design equation (Eplan) from the software Statistica Experimental Design? (version 7.0), and the other obtained from a modeling equation based on a dimensional analysis (Ecalc). The results shows that the experimental design equation gives a good prediction of the unit efficiencies with better data reliability, regarding to the condition before a run operation. The average deviation between the proposed by statistic planning model equation and experimental data was 0.13%. On the other hand, the efficiency calculated by the equation which represents the dimensional analysis, may result on important relative deviations (up 70%). Thus, the experimental design is confirmed as a reliable tool, with regard the experimental data processing of the MSPI-TU / Este trabalho objetiva determinar a melhor metodologia para auxiliar na predi??o de vari?veis operacionais de um novo design de misturador-decantador aplicado ao tratamento de ?guas produzidas da ind?stria do petr?leo, que vem sendo denominado de MDIF (Misturador-Decantador ? Invers?o de Fases). Os dados utilizados neste estudo foram obtidos da Unidade de Tratamento de ?guas produzidas, denominada de UT-MDIF, que se encontra instalada em uma das esta??es de tratamento de efluentes (ETE) da PETROBRAS/UORNCE. A import?ncia em determinar a melhor metodologia que permita a predi??o dos resultados das efici?ncias de separa??o e extra??o do equipamento, contribui de forma significativa para otimiza??o das vari?veis operacionais para o controle da unidade. O estudo se baseou na compara??o dos resultados das efici?ncias experimentais (E) obtidas pela UTMDIF, com os resultados das efici?ncias obtidas pela equa??o do modelo do planejamento estat?stico (Eplan), gerado pelo programa Statistica Experimental Design? (vers?o 7.0), e com a utiliza??o de uma equa??o utilizando modelagem com base em an?lise dimensional (Ecalc). Os resultados mostram que a equa??o decorrente do planejamento estat?stico ? capaz de predizer, com boa aproxima??o, os resultados de efici?ncia a serem obtidos com a unidade, possibilitando uma melhor confiabilidade dos dados, no que se refere ? condi??o que antecede uma corrida operacional. O desvio m?dio entre a equa??o proposta e os dados experimentais ? de 0,13%. Por outro lado, a efici?ncia calculada pela equa??o da an?lise dimensional pode apresentar desvios relativos importantes (at? 70%). Desta forma, o planejamento estat?stico experimental se confirma como sendo uma ferramenta confi?vel, no que se refere ao tratamento dos dados experimentais da UT-MDIF

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