Dissertations / Theses: 'Flow lip'

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Rocke, Ann H. "Elastohydrodynamic Analysis of a Rotary Lip Seal Using Flow Factors." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4771.

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An elastohydrodynamic analysis of a rotary lip seal is performed numerically, incorporating both the fluid mechanics of the lubricating film and the elastic deformation of the lip, by solving the Reynolds equation with flow factors. Asperities on the lip surface dominate the behavior of the flow field in the lubricating film and the elastic deformation of the lip. Since previous analyses treated those asperities deterministically, they required very large computation times. The present approach is much less computationally intensive because the asperities are treated statistically. Since cavitation and asperity orientation play important roles, these are taken into account in the computation of the flow factors. An asperity distortion analysis is introduced to obtain a more realistic model of the complex variations in the asperity distribution on the surface of the seal. Results of the analysis show how the operating parameters of the seal and the characteristics of the asperities affect such seal characteristics as the thickness of the lubricating film, reverse pumping rate, power dissipation and load carrying capacity.

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Baudrit, Daniel 1957. "FLOW MEASUREMENT USING A SENSING DEVICE NEAR THE LIP OF A GATE (CANALS, OPEN CHANNEL FLOW)." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/275569.

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Neal, Mark. "A study of the brass instrument lip reed mechanism using artificial lips and lattice Boltzmann flow simulations." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/12707.

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The lips of a brass player form a complex mechanical oscillator which has a non-harmonic set of resonance frequencies. In order for the lips to create a note when a player starts to play a brass instrument there must be interactions between the mechanical resonances of the lips, the fluid dynamics of the air passing between the lips, and the acoustic pressures which surrounding the lips. In this thesis studies are made of these interactions utilising an artificial lip and mouth to perform experimental measurements and Lattice Boltzmann fluids simulations to study the flow of air between the lips. By taking mechanical response measurements of the artificial lips, the mechanical resonances of the lips has been examined. The effects of both air flow between the lips and the presence of acoustic resonators, both in the form of an instrument on the downstream side of the lips and the mouth cavity on the up-stream side of the lips have been studied. Results of these measurements have shown that the lips of a brass player can behave in either of two lip reed operating regimes (inward or outward striking), depending on the relationship between the resonance frequency of the lips and that of the resonator. The behaviour of the lips during the transition between inward and outward striking regimes has been studied in order that improved models of the lip reed can be constructed. Numerical simulations of the flow in a pipe with a constriction which is based on the shape of a players lips both with and without a mouthpiece downstream of the lips have provided information on how the jet formation by the lips occurs. By using the data from these simulations the size of the forces which lead to the inward and outward striking behaviour of the lips have been estimated and a clearer picture of the physics behind the operation of a brass players lips obtained.

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Jafari, Moghadamfard Ramtin, and Saeid Payvar. "The Potential of Visual Features : to Improve Voice Recognition Systems in Vehicles Noisy Environment." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-27273.

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Multimodal biometric systems have been subject of study in recent decades, theirunique characteristic of Anti spoofing and liveness detection plus ability to deal withaudio noise made them technology candidates for improving current systems such asvoice recognition, verification and identification systems.In this work we studied feasibility of incorporating audio-visual voice recognitionsystem for dealing with audio noise in the truck cab environment. Speech recognitionsystems suffer from excessive noise from the engine and road traffic and cars stereosystem. To deal with this noise different techniques including active and passive noisecancelling have been studied.Our results showed that although audio-only systems are performing better in noisefree environment their performance drops significantly by increase in the level of noisein truck cabins, which by contrast does not affect the performance of visual features.Final fused system comprising both visual and audio cues, proved to be superior toboth audio-only and video-only systems.

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GuÌˆrcan, Fuat. "Flow bifurcations in rectangular, lid-driven, cavity flows." Thesis, University of Leeds, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425523.

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Netto, Cristianne Chiquto. "Área velofaríngea e escape de ar nasal nas condições com e sem prótese de palato." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/25/25143/tde-26042016-102947/.

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Introdução: Embora a avaliação perceptivo-auditiva seja reconhecida como padrão ouro na avaliação clínica da fala de pacientes com fissura palatina e/ou disfunção velofaríngea (DVF), ela pode ser influenciada por inúmeros fatores, dada a sua subjetividade. A avaliação instrumental, como a técnica fluxo-pressão, pode complementar os achados de fala e da função velofaríngea em indivíduos que utilizam prótese de palato com obturador faríngeo para o tratamento da DVF. Objetivos: Descrever e comparar os resultados das medidas da área velofaríngea, por meio da técnica fluxo-pressão, e do julgamento da ocorrência do EAN durante a repetição de palavras com a consoante p e da emissão da palavra papai, durante a realização do Teste de Emissão de Ar Nasal (TEAN), nas condições com e sem prótese de palato e verificar a relação entre a ocorrência do EAN e a classificação da função velofaríngea, nas condições com (CP) e sem (SP) prótese de palato. Material e Métodos: Foi realizado um estudo observacional transversal de uma amostra de conveniência de 94 pacientes com diagnóstico de insuficiência velofaríngea que utilizavam prótese de palato com obturador faríngeo. A classificação do tipo de função velofaríngea (adequada, adequada-marginal, marginal-inadequada e inadequada) foi realizada a partir da medida da área velofaríngea obtida pela técnica fluxo-pressão, durante a produção da consoante p inserida na sílaba pa. Foram coletados dos prontuários dos pacientes os resultados do julgamento da ocorrência (presença/ausência) do EAN durante a repetição de palavras com p e da emissão da palavra papai do TEAN, nas condições sem e com prótese de palato. Resultados: A medida da área velofaríngea e o julgamento da ocorrência do EAN mostraram-se significativamente menores na condição CP. Entretanto, a prótese conseguiu eliminar o EAN em 63,9% dos pacientes, quando se toma a emissão de palavras com a consoante p na avaliação articulatória para comparação, e eliminá-lo em 50% deles quando se toma a emissão da palavra papai do TEAN. Com a prótese, 56,4% pacientes apresentaram função velofaríngea adequada e 43,6% função velofaríngea diferente da adequada (adequada-marginal = 5,3%, marginal-inadequada = 5,3%, inadequada = 33%). Conclusões: As medidas da área velofaríngea obtidas por meio da técnica fluxopressão diminuem significativamente quando o paciente faz uso da prótese (condição com prótese), revelando que a prótese pode melhorar a função velofaríngea para a fala; embora a ocorrência do escape de ar nasal (EAN) na produção da consoante p demonstre ser menor com a prótese, tanto no julgamento pela modalidade auditiva quanto pela visual, a modalidade visual parece ser mais sensível para identificar a ocorrência do escape;o EAN demonstrou ter relação direta com a função velofaríngea, uma vez que apresentou-se ausente em uma função velofaríngea adequada (condição com prótese) e presente em uma função velofaríngea inadequada (condição sem prótese). Contudo, esta relação pode estar susceptível à interferência de muitos fatores que podem influenciar positivamente ou negativamente a ocorrência do EAN na função velofaríngea.
Introduction: Although perceptual judgement is recognized to be the gold standard for clinical speech evaluation of cleft palate and/or velopharyngeal dysfunction (VPD) patients, it can be influenced by a number of factors due to its subjectivity. Instrumental assessment such as pressure-flow technique can provide additional information related to speech and velopharyngeal dysfunction findings in individuals adapted to palatal speech device with obturator pharyngeal bulb for treatment of VPD Objectives: Describe and compare the results of velopharyngeal area measurements by using pressure-flow technique and the judgment of the occurrence of air nasal emission (NAE) during repetition of words containing the p consonant and utterance of the word papai in the Test of Nasal Air Emission (TNAE), in conditions with and without palatal speech device as well as to analyze the relation between NAE and velopharyngeal dysfunction ratings in conditions with and without palatal speech device.Method: A retrospective study of samples including 94 patients with diagnosis of velopharyngeal insufficiency wearing palatal prostheses with pharyngeal bulb was performed. Velopharyngeal function was rated (adequate, marginal-adequate, marginal-inadequate and inadequate) in according to velopharyngeal measurements obtained from aerodynamic evaluation during the production of p consonant in the segment pa. The results of NAE occurrence judgement (present/absent) during the repetition of words with p and utterance of papai in the TNAE were collected from the patients´s recordings, in the conditions with and without prosthesis. Results: Velopharyngeal area measurements and NAE occurrence judgement were significantly lower in the with-prosthesis condition. However, speech prosthesis was able to eliminate NAE in 63.9% of the patients, when considering utterances of words with p in articulatory evaluation as comparison, and managed to eliminate it by 50% of them with regard to the word papai in the TEAN. With the speech device, 56.4% of patients demonstrated adequate velopharyngeal function and 43.6% showed velopharyngeal ratings different of the adequate one (marginal adequate = 5.3%, marginal inadequate = 5.3% and inadequate = 33%).Conclusions: The measures of velopharyngeal area obtained byusing pressure-flow technique decreased significantly when the patient uses prosthesis (condition with prosthesis), revealing that the prosthetic device can improve velopharyngeal function for the speech. Although the occurrence of nasal air flow (EAN) in the production of the consonant p presents to be lower with prosthesis, either in the hearing judgement as in the visual one, the latter seems to be more sensible to identify the occurrence of flow. Nasal air flow (EAN) demonstrated to have a direct relation with the velopharyngeal function for it was absent in an adequate velopharyngeal function (condition with prosthesis) and present in an inadequate velopharyngeal function (condition without prosthesis). Nevertheless, this relation may be susceptible to the interference of many factors that may positively or negatively influence the occurrence of EAN in the velopharyngeal function.

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Borges, Rodrigo Lopes. "A fam?lia Rubiaceae na Serra Geral de Lic?nio de Almeida." Universidade Estadual de Feira de Santana, 2016. http://localhost:8080/tede/handle/tede/413.

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In Brazil, Rubiaceae is the fourth family with greater diversity of species and is represented by 125 genera and 1392 species, mostly distributed in the Amazon and Atlantic forests. Due to the heterogeneity of habitat and vegetation types, Bahia stands out for the richness of species in the family (ca. 368 spp.) and by the record of many endemic species. Among the areas that are recognized by the lack of floristic inventories in the state, there is the southwest region, more precisely the areas that comprise the Espinha?o Septentrional. Thus, the aim of this study was to conduct a floristic and taxonomic survey of Rubiaceae to the Serra Geral of Lic?nio de Almeida (SGLA), Bahia. Ten field trips were conducted between July 2012 and May 2015, covering all existing vegetation types in the area. The collected materials were processed and deposited in the HUEFS and ALCB herbaria. Reference materials were also analyzed in visits to herbaria ALCB, CEPEC, HRB, HUEFS, RB and SPF. A number of 43 species distributed in 28 genera were recognized and collected, being Declieuxia (5 spp.), Borreria (3 spp.), Cordiera (3 spp.) and Psychotria (3 spp.) the most diverse genera. Following the previous floristic studies in Espinha?o Range, there are large number of genera (19) with only a single species. Psyllocarpus asparagoides, Psyllocarpus laricoides and Stachyarrhena reflexa are endemic to Minas Gerais and Bahia; Declieuxia passerina and Galianthe peruviana are new records for Bahia, and two species are considered new for science (Randia sp. and Staelia sp.). Keys to generic and specific identification, descriptions, taxonomic and biologic comments for all species are presented, as well as photos and illustrations.
Rubiaceae ? a quarta fam?lia com maior riqueza de esp?cies no Brasil e est? representada por 125 g?neros e 1392 esp?cies, distribu?das predominantemente nos dom?nios Amaz?nico e Atl?ntico. Devido ? heterogeneidade de habitats e fitofisionomias, a Bahia destaca-se pela riqueza de esp?cies para a fam?lia (ca. 368 spp.) e pelo registro de muitas esp?cies end?micas. Dentre as ?reas que s?o reconhecidas pela car?ncia de invent?rios flor?sticos no estado, destaca-se a regi?o sudoeste, mais precisamente as ?reas que compreendem o Espinha?o Setentrional. Desta forma, o objetivo deste estudo foi realizar o levantamento flor?stico e taxon?mico de Rubiaceae para a Serra Geral de Lic?nio de Almeida (SGLA), Bahia. Foram realizadas dez viagens de coleta entre julho de 2012 e maio de 2015, abrangendo todas as fitofisionomias existentes na ?rea. Os materiais coletados foram processados e depositados nos Herb?rios HUEFS e ALCB. Materiais de refer?ncia foram tamb?m analisados em visita aos herb?rios ALCB, CEPEC, HRB, HUEFS, RB, SPF. Foram reconhecidas e coletadas 43 esp?cies, distribu?das em 28 g?neros, sendo Declieuxia (5 spp.), Borreria (3 spp.), Cordiera (3 spp.) e Psychotria (3 spp.) os g?neros mais diversos e, seguindo os estudos flor?sticos pr?vios na Cadeia do Espinha?o, houve um grande n?mero de g?neros (19) com apenas uma ?nica esp?cie. Psyllocarpus asparagoides, Psyllocarpus laricoides, Stachyarrhena reflexa s?o end?micas de Minas Gerais e Bahia; Declieuxia passerina e Galianthe peruviana s?o novas ocorr?ncias para a Bahia, e duas esp?cies s?o consideradas in?ditas para a ci?ncia (Randia sp. e Staelia sp.). S?o apresentados chaves de identifica??o gen?rica e espec?fica, descri??es, coment?rios taxon?micos para as esp?cies, al?m de fotos e ilustra??es.

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Santana, Fernanda Afonso. "A fam?lia Asteraceae na Serra Geral de Lic?nio de Almeida, Bahia, Brasil." Universidade Estadual de Feira de Santana, 2013. http://localhost:8080/tede/handle/tede/285.

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Serra Geral de Lic?nio de Almeida (SGLA) is located in the central portion of the Espinha?o range, a region with no floristic studies. This paper presents the inventory of Asteraceae for the SGLA. Samples were collected in six bimonthly field trips (2011-2012) and the collected materials are inserted at HUEFS Herbarium. The results are presented in the checklist of the species, keys to tribes and species, followed by comments, aspects of reproductive phenology and geographical distribution of each species. Eighty-three species and 38 genera were found, represented in 12 tribes of Asteraceae. Of these, 13 are new records for Bahia state (Aldama oblongifolia, Aldama bracteata, Aspilia eglerii, Aspilia floribunda, Dasyphyllum vagans, Eremanthus polycephalus, Gochnatia discolor, Lychnophora ramosissima, Lepidaploa barbata, Lessingianthus laevigatus, Lessingianthus psilophyllus, Mikania obtusata e Proteopsis argentea) and two are new species to science (Lychnophora sp. 1 and Anteremanthus sp. nov.). The most representative tribe was Vernonieae (36 spp.), followed by Eupatorieae (17 spp.) and Heliantheae (8 spp.). The genera with the largest number of species were Lessingianthus (eight spp.), followed by Lepidaploa, Vernonanthura and Gochnatia, with five species each. A map of the study area with the respective collection sites and unpublished illustrations of Agrianthus myrtoides, Aspilia floribunda, Anteremanthus sp. nov., Chresta harleyi, Gochnatia densicephala, Lychnophora sp. 1 and Stomatanthes polycephalus are included as part of the results.
A Serra Geral de Lic?nio de Almeida (SGLA) est? localizada na por??o central da Cadeia do Espinha?o, regi?o carente em pesquisas bot?nicas. Neste trabalho ? apresentado um levantamento flor?stico da flora de Asteraceae para a SGLA. As coletas foram realizadas atrav?s de seis viagens bimestrais (2011-2012) ao campo e o material coletado encontra-se inserido no Herb?rio HUEFS. Os resultados s?o apresentados atrav?s do checklist das esp?cies, chaves de tribos e de esp?cies, seguido de coment?rios diagn?sticos, aspectos da fenologia reprodutiva e distribui??o geogr?fica de cada t?xon. Foram encontrados 12 tribos, 38 g?neros e 82 esp?cies. Destas, 13 s?o novas ocorr?ncias para o estado da Bahia (Aldama oblongifolia, Aldama bracteata, Aspilia eglerii, Aspilia floribunda, Dasyphyllum vagans, Eremanthus polycephalus, Gochnatia discolor, Lychnophora ramosissima, Lepidaploa barbata, Lessingianthus laevigatus, Lessingianthus psilophyllus, Mikania obtusata e Proteopsis argentea) e duas s?o esp?cies novas para a ci?ncia (Lychnophora sp. 1 e Anteremanthus sp. nov.). A tribo mais representativa foi Vernonieae (36 spp.), seguida de Eupatorieae (17 spp.) e Heliantheae (oito spp.). O g?nero com maior n?mero de esp?cies foi Lessingianthus (oito spp.), seguido de Lepidaploa, Vernonanthura e Gochnatia, com cinco esp?cies cada. Como parte dos dados ? inclu?do o mapa da ?rea de estudo e as respectivas localidades de coleta, al?m das ilustra??es in?ditas de Agrianthus myrtoides, Aspilia floribunda, Anteremanthus sp. nov., Chresta harleyi, Gochnatia densicephala, Lychnophora sp. 1. e Stomatanthes polycephalus.

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Vionnet, Carlos Alberto. "Analysis of lubricant flows within the microgap of rotary lip seals." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186465.

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The study of a thin, incompressible Newtonian fluid layer trapped between two almost parallel, sliding surfaces has been actively pursued in the last decades. This subject includes lubrication applications such as slider bearings or the sealing of non-pressurized fluids with rotary lip seals. When a viscous lubricant flows between an elastic body and a rigid surface, the contact geometry may undergo substantial deformation affecting the flow field of the lubricant. Therefore, a coupled model between an elastic ring and the fluid film underneath it is proposed. Initially, a linear stability analysis is performed. Then, non-linear calculations are presented showing that the system deformations are able to induce mixing of lubricant throughout the sealed region. In the second part of this work, the flow of lubricant fluid through the micro-gap of rotary lip seals is analyzed theoretically and numerically from a different perspective. The study is carried out assuming that a 'small-gap' parameter δ attains an extreme value in the Navier-Stokes equations. The precise meaning of small-gap is achieved by the limit δ = 0, and the numerical solution of the resulting set of equations predicts transport of lubricant through the contact region due to centrifugal instabilities. Numerical results obtained with the finite element method are presented. In particular, the influence of inflow and outflow boundary conditions, and their importance in the simulated flow are discussed. To this aim, the penalty method for incompressible flows in presence of variable body forces is re-examined with the help of well-known examples, yielding a corrected formulation that is more accurate and faster than standard finite element methods found in the literature.

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Benson, John D. "Transition to a time periodic flow in a through-flow lid-driven cavity." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/18179.

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SCHOTTLER, ALLAN WERNER. "VISUALIZING FLOW IN BLACK-OIL RESERVOIRS USING VOLUMETRIC LIC." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=35850@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Na indústria de petróleo, é imprescindível a visualização clara e desambigua de campos vetoriais resultantes de simulações numéricas de reservatórios de petróleo. Nesta dissertação, estudamos o uso da convolução de integral de linha (Line Integral Convolution – LIC) para gerar imagens de campos vetoriais 3D estacionários e aplicar o resultado em um visualizador volumétrico na GPU. Devido a densidade de informação presente na visualização volumétrica, estudamos os uso de texturas esparsas como entrada para o algoritmo de LIC e aplicamos funções de transferência para designar cor e opacidade a volumes de campos escalares, a fim de codificar informações visuais a voxels e aliviar o problema de oclusão. Além disso, tratamos o problema de codificação da direção de fluxo, inerente do LIC, usando uma extensão do algoritmo – Oriented LIC (OLIC). Por último, demonstramos um método de animação do volume a fim de ressaltar a direção do fluxo ainda mais. Comparamos então resultados do algoritmo LIC com o de OLIC.
In the oil industry, clear and unambiguous visualization of vector fields resulting from numerical simulations of black-oil reservoirs is essential. In this dissertation, we study the use of line integral convolution techniques (LIC) for imaging 3D steady vector fields and apply the results to a GPU-based volume rendering algorithm. Due to the density of information present in volume renderings of LIC images, we study the use of sparse textures as input to the LIC algorithm and apply transfer functions to assign color and opacity to scalar fields in order to encode visual information to voxels and alleviate the occlusion problem. Additionally, we address the problem of encoding flow orientation, inherent to LIC, using an extension of the algorithm – Oriented LIC (OLIC). Finally, we present a method for volume animation in order to enhance the flow orientation. We then compare results obtained with LIC and with OLIC.

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Mendes, Fernando Augusto Alves. "Estudo experimental do funcionamento de um sistema gas-lif /." Ilha Solteira: [s.n.], 2007. http://hdl.handle.net/11449/88853.

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Resumo: O princípio de funcionamento de um sistema gas-lift é bastante simples, baseando-se na injeção de um gás inerte próximo à extremidade submersa de um tubo utilizado para ascensão do líquido (riser). Esse sistema tem sido utilizado em diversos setores da indústria, dentre os quais se destaca o setor petroquímico. Apesar de ter sido concebido há mais de um século, e a despeito do considerável número de artigos publicados sobre o assunto, vários aspectos relativos às características do escoamento bifásico dentro do riser e ao funcionamento do sistema são, ainda, pouco conhecidos. No presente trabalho, um sistema air-lift de pequeno porte foi inteiramente desenvolvido e testado, permitindo observar o comportamento do sistema quando submetido a variações na vazão de ar, na razão de submersão e na geometria do injetor - contendo três (3F) ou quinze furos (15F). Ensaios de visualização foram conduzidos, possibilitando a caracterização do escoamento bifásico no interior do riser. Medições experimentais foram, também, realizadas para a obtenção da eficiência e das curvas características do sistema. Os resultados quantitativos foram interpretados em associação com imagens estáticas do escoamento, capturadas com uma câmera fotográfica digital, e com imagens dinâmicas, tomadas com o auxílio de uma filmadora de alta velocidade. A partir destas imagens, foi possível, ainda, a estimativa de alguns importantes parâmetros característicos do escoamento pistonado, associados ao deslocamento da chamada bolha de Taylor. Os dados assim obtidos foram comparados com valores oriundos de correlações empíricas propostas por outros autores, apresentando boa concordância. Com relação aos resultados quantitativos, observou-se que, sob determinadas condições de operação, o injetor 3F é capaz de atribuir ao sistema um rendimento significativamente maior... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The operation principle of a gas-lift system is very simple: it is based on the injection of an inert gas close to the immersed edge of a tube, which is used for the rising of the liquid (riser). This system has been used in several industrial areas and more often in the petrochemical industry. Despite the fact that it was conceived over a century ago and that there have been a considerable amount of articles published on the subject, several aspects concerning the two-phase flow characteristics inside the riser as well as its operational system are still not very well known. In the present work, a small size air-lift system was thoroughly developed and tested, which facilitated the visualization of the system behavior when submitted to variations in the air flow, the immersion ratio and the injector geometry - containing three (3H) or fifteen holes (15H). Observation experiments were carried out making it possible to characterize the two-phase flow inside the riser. Experimental measurements were also taken in order to obtain the system characteristic efficiency and slopes. The quantitative results were analyzed together with the statistic images of the flow - taken by a digital photo camera, and with the dynamic images - taken by a high-speed filming camera. Through these images, it was also possible to estimate some important characteristic parameters of the slug flow associated to the displacement of the so-called Taylor bubble. The data obtained this way were compared to the figures originated from experimental correlations proposed by other authors, and they showed a fine agreement. Regarding the quantitative results, it was observed that under certain operation conditions the 3F injector is able to give the system a significantly greater efficiency than when the 15F injector is used
Orientador: Sérgio Said Mansur
Coorientador: Edson Del Rio Vieira
Banca: André Luiz Seixlack
Banca: Ricardo Augusto Mazza
Mestre

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Farrugia, N. "Vector-scalar imaging in combustion using PIV and LIF." Thesis, Cranfield University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309583.

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Mendes, Fernando Augusto Alves [UNESP]. "Estudo experimental do funcionamento de um sistema gas-lif." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/88853.

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O princípio de funcionamento de um sistema gas-lift é bastante simples, baseando-se na injeção de um gás inerte próximo à extremidade submersa de um tubo utilizado para ascensão do líquido (riser). Esse sistema tem sido utilizado em diversos setores da indústria, dentre os quais se destaca o setor petroquímico. Apesar de ter sido concebido há mais de um século, e a despeito do considerável número de artigos publicados sobre o assunto, vários aspectos relativos às características do escoamento bifásico dentro do riser e ao funcionamento do sistema são, ainda, pouco conhecidos. No presente trabalho, um sistema air-lift de pequeno porte foi inteiramente desenvolvido e testado, permitindo observar o comportamento do sistema quando submetido a variações na vazão de ar, na razão de submersão e na geometria do injetor – contendo três (3F) ou quinze furos (15F). Ensaios de visualização foram conduzidos, possibilitando a caracterização do escoamento bifásico no interior do riser. Medições experimentais foram, também, realizadas para a obtenção da eficiência e das curvas características do sistema. Os resultados quantitativos foram interpretados em associação com imagens estáticas do escoamento, capturadas com uma câmera fotográfica digital, e com imagens dinâmicas, tomadas com o auxílio de uma filmadora de alta velocidade. A partir destas imagens, foi possível, ainda, a estimativa de alguns importantes parâmetros característicos do escoamento pistonado, associados ao deslocamento da chamada bolha de Taylor. Os dados assim obtidos foram comparados com valores oriundos de correlações empíricas propostas por outros autores, apresentando boa concordância. Com relação aos resultados quantitativos, observou-se que, sob determinadas condições de operação, o injetor 3F é capaz de atribuir ao sistema um rendimento significativamente maior...
The operation principle of a gas-lift system is very simple: it is based on the injection of an inert gas close to the immersed edge of a tube, which is used for the rising of the liquid (riser). This system has been used in several industrial areas and more often in the petrochemical industry. Despite the fact that it was conceived over a century ago and that there have been a considerable amount of articles published on the subject, several aspects concerning the two-phase flow characteristics inside the riser as well as its operational system are still not very well known. In the present work, a small size air-lift system was thoroughly developed and tested, which facilitated the visualization of the system behavior when submitted to variations in the air flow, the immersion ratio and the injector geometry – containing three (3H) or fifteen holes (15H). Observation experiments were carried out making it possible to characterize the two-phase flow inside the riser. Experimental measurements were also taken in order to obtain the system characteristic efficiency and slopes. The quantitative results were analyzed together with the statistic images of the flow - taken by a digital photo camera, and with the dynamic images – taken by a high-speed filming camera. Through these images, it was also possible to estimate some important characteristic parameters of the slug flow associated to the displacement of the so-called Taylor bubble. The data obtained this way were compared to the figures originated from experimental correlations proposed by other authors, and they showed a fine agreement. Regarding the quantitative results, it was observed that under certain operation conditions the 3F injector is able to give the system a significantly greater efficiency than when the 15F injector is used

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15

Lemée, Thomas. "Shear-flow instabilities in closed flow." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112038.

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Cette étude se concentre sur la compréhension de la physique des instabilités dans différents écoulements de cisaillement, particulièrement la cavité entraînée et la cavité thermocapillaire, où l'écoulement d'un fluide incompressible est assuré soit par le mouvement d’une ou plusieurs parois, soit par des contraintes d’origine thermique.Un code spectral a été validé sur le cas très étudié de la cavité entrainée par une paroi mobile. Il est démontré dans ce cas que l'écoulement transit d'un régime stationnaire à un instationnaire au-delà d'une valeur critique du nombre de Reynolds. Ce travail est le premier à donner une interprétation physique de l'évolution non monotonique du nombre de Reynolds critique en fonction du facteur d'aspect. Lorsque le fluide est entraîné par deux parois mobiles, la cavité entraînée possède un plan de symétrie particulièrement sensible. Des solutions asymétriques peuvent être observés en plus de la solution symétrique au-dessus d'une certaine valeur du nombre de Reynolds. La transition oscillatoire entre la solution symétrique et les solutions asymétriques est expliquée physiquement par les forces en compétition. Dans le cas asymétrique, l'évolution de la topologie permet à l'écoulement de rester stationnaire avec l'augmentation du nombre de Reynolds. Lorsque l'équilibre est perdu une instabilité se manifeste par l'apparition d'un régime oscillatoire dans l'écoulement asymétrique.Dans une cavité thermocapillaire rectangulaire avec une surface libre, Smith et Davis prévoient deux types d'instabilités convectives thermiques: des rouleaux longitudinaux stationnaires et des ondes hydrothermales instationnaires. L'apparition de ses instabilités a été mis en évidence à plusieurs reprises expérimentalement et numériquement. Alors que les applications impliquent souvent plus d'une surface libre, il semble qu'il y ait peu de connaissances sur l'écoulement thermocapillaire entraînée avec deux surfaces libres. Un film liquide libre soumis à des contraintes thermocapillaires possède un plan de symétrie particulier comme dans le cas de la cavité entrainée par deux parois mobiles. Une étude de stabilité linéaire avec deux profils de vitesse pour le film liquide libre est présentée avec différents nombres de Prandtl. Au-delà d'un nombre de Marangoni critique, il est découvert que ces états de base sont sensibles à quatre types d'instabilités convectives thermiques qui peuvent conserver ou briser la symétrie du système. Les mécanismes qui permettent de prédire ces instabilités sont également découverts et interpréter en fonction de la valeur du nombre de Prandtl du fluide. La comparaison avec les travaux de Smith et Davis est faite. Une simulation numérique directe permet de valider les résultats obtenus avec l'étude de stabilité de linéaire
This study focuses on the understanding of the physics of different instabilities in driven cavities, specifically the lid-driven cavity and the thermocapillarity driven cavity where flow in an incompressible fluid is driven either due to one or many moving walls or due to surface stresses that appear from surface tension gradients caused by thermal gradients. A spectral code is benchmarked on the well-studied case of the lid-cavity driven by one moving wall. In this case, It is shown that the flow transit form a steady regime to unsteady regime beyond a critical value of the Reynolds number. This work is the first to give a physical interpretation of the non-monotonic evolution of the critical Reynolds number versus the size of the cavity. When the fluid is driven by two facing walls moving in the same direction, the cavity possesses a plane of symmetry particularly sensitive. Thus, asymmetrical solutions can be observed in addition to the symmetrical solution above a certain value of the Reynolds number. The oscillatory transition between the symmetric solution and asymmetric solutions is explained physically by the forces in competition. In the asymmetric case, the change of the topology allows the flow to remain steady with increasing the Reynolds number. When the equilibrium is lost, an instability manifests by the appearance of an oscillatory regime in the asymmetric flow. In a rectangular cavity thermocapillary with a free surface, Smith and Davis found two types of thermal convective instabilities: steady longitudinal rolls and unsteady hydrothermal waves. The appearance of its instability has been highlighted repeatedly experimentally and numerically. While applications often involve more than a free surface, it seems that there is little knowledge about the thermocapillary driven flow with two free surfaces. A free liquid film possesses a particular plane of symmetry as in the case of the two-sided lid-driven cavity. A linear stability analysis for the free liquid film with two velocity profiles is presented with various Prandtl numbers. Beyond a critical Marangoni number, it is observed that these basic states are sensitive to four types of thermal convective instabilities, which can keep or break the symmetry of the system. Mechanisms that predict these instabilities are discovered and interpreted according to the value of the Prandtl number of the fluid. Comparison with the work of Smith and Davis is made. A direct numerical simulation is done to validate the results obtained with the linear stability analysis

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Johansson, Mats. "Simulation of a multi phase flow in a rotating-lid driven cylinder." Thesis, Umeå universitet, Institutionen för fysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-82177.

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This report describes the development of a software for computing viscous incompressiblemultiphase ows. The software does this with solving the coupled non-linear Navier-Stokes(Fluid) and the Cahn-Hilliard (Phase-Field) equations using a Finite Element Method. Thereason for the development is to produce a simulation tool, which eventually is capable ofsimulating the ow of uids inside the OptusAir aeronator manufactured by the Sorubincompany. The solving software developed is built on the ParMetis, PETSc and OpenMPIframeworks. Our primary benchmark has been a geometry resembling the OptusAir product,a cylinder with a rotating bottom. We have made comparisons between simulation resultsand the theory of a free surface in a uniform rotating ow.This thesis shows that the shape of the interface between two uids coincides with theoryto some extent, while the approximate boundary conditions prevent it from coinciding fully.

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Seegmiller, Patrick. "Explicit Construction of First Integrals for the Toda Flow on a Classical Simple Lie Algebra." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4699.

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The Toda flow is a Hamiltonian system which evolves on the dual of the Borel subalgebra of a complex Lie algebra g. The dual of the Borel subalgebra can be identified with an affine subspace of its negative plus the element given by the sum of the simple root vectors in g. The system has been proven completely integrable in the Liouville sense on a generic coadjoint orbit for the Borel subgroup. This paper gives a verification of integrability of the Toda flow on classical simple Lie algebras and describes a method for the construction of a complete collection of integrals of motion for each. After this description, an implementation of the outlined procedures is given in the Maple programming environment, together with explicit examples, demonstrating both the accuracy of the procedure and the efficacy of the Maple programming code.

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Maisto, Pietro. "Experimental analysis and prospective flow diagnostic applications for fluorescence dye-doped microparticles." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/64835.

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The work described focuses on characterization of fluorescence dye-doped polystyrene latex particles (PSLs) dispersed in air as a candidate for advanced flow diagnostic techniques for applications in wind tunnels. PSLs with mean diameter on the order of 1 μm were provided by collaborators at NASA Langley Research Center and measurements of simultaneous Mie scattering and laser induced fluorescence (LIF) signals were obtained with the goal of providing a capability for velocity and scalar flow measurements. Three organic fluorescent dyes, Rhodamine B (RhB), Dichlorofluorescein (DCF), and Kiton Red (KR), were doped into PSLs and studied in benchtop experiments. A major interest in the present research is the application of safe dyes, thus DCF and KR are of particular interest, while RhB is used as a benchmark. The study is broken up into two major elements: response of the particles to continuous wave (CW) excitation, and response to pulsed excitation. The former was examined for mean LIF imaging and single-point single-shot measurements, the latter for planar single-shot measurements. The LIF signal has several potential uses, though the primary interest herein is the reduction of flare from wind tunnel walls which occurs at the laser excitation wavelength and the use of the fluorescence signal for sensing temperature. It is demonstrated that the LIF signal under CW excitation may be used for velocimetry with the laser-Doppler velocimetry technique, thus effective in filtering out the laser flare in the vicinity of wind tunnel models or walls. A two-band LIF technique was also demonstrated for one of the DCF batches, indicating that the technique effectively removes interfering inputs such as particle diameter and dye concentration variation. Temperature measurement uncertainties are estimated based upon the variance measured for the two-band LIF intensity ratio and the achievable dye temperature sensitivity, indicating that particles developed to date may provide about 12.5 degrees C precision. Pulsed excitation with an Nd:YAG laser at about 200mJ/pulse at 532 nm yield no fluorescence above the detection threshold of the cameras used from the DCF batch examined. However, a batch doped with Kiton Red 620 was shown to provide sufficient intensity of LIF for single-shot planar measurements such as PIV via planar LIF. The KR batch also exhibited highly non-uniform yield of fluorescence signal on a particle-to-particle basis - this despite a highly uniform Mie scattering signal. Given the uniform Mie signal and a relatively narrow Gaussian distribution of the particles size, a possible mechanism is mentioned for the LIF non-uniformity as lasing within individual particles due to whispering gallery mode resonance.
Master of Science

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Birembaux, Olivier. "Actions de groupes résolubles scindement de f-fibres hermitiens." Valenciennes, 1997. https://ged.uphf.fr/nuxeo/site/esupversions/b7bd7233-5e92-4465-8cce-ff9ef4078593.

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Première partie : Soient G un groupe de Lie connexe de dimension n - 1, f une action localement libre de classe Cr (avec r supérieure ou égale à 2) de G sur une variété compacte M de dimension n supérieure ou égale a 3. Nous supposons qu'il existe dans l'algèbre de Lie de G un champ Y tel que la partie réelle de chaque valeur propre de ad(Y) soit strictement plus petite que 0. Alors, nous montrons que f est Cr -conjuguée à une action modèle de G sur un espace homogène H/T ou H est un groupe de Lie contenant G. Nos hypothèses impliquent que G a une structure particulière, mais il existe quand même de nombreux exemples : Notamment, la famille des groupes G ayant cette propriété est continue en toute dimension plus grande que 4 ; pour un choix générique de G, le groupe H correspondant n'a aucun quotient compact de dimension n, et ceci fournit une famille continue de groupes de Lie ne possédant aucune action de codimension 1 suffisamment régulière sur une variété compacte. Ces résultats sont liés à la théorie d'Anosov. Deuxième partie : Soient M une variété C connexe, munie d'un flot F et E un F-fibré hermitien au-dessus de M. On donne une version basique du théorème de Leray-Hirsch pour le fibré P(E), projectifié de E. Ensuite on établit un « principe de scindement » feuilleté, i. E on montre qu'il existe une variété B munie d'un flot V et une application feuilletée σ : B vers M telles que le fibré vectoriel image réciproque σ -1 E se décompose en somme directe de V-fibrés hermitiens Si de rang 1 et l'application σ*, induite en cohomologie basique, est injective.

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Liu, Ying. "Outlier detection by network flow." Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2007p/liu-ying.pdf.

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Thesis (Ph. D.)--University of Alabama at Birmingham, 2007.
Additional advisors: Elliot J. Lefkowitz, Kevin D. Reilly, Robert Thacker, Chengcui Zhang. Description based on contents viewed Feb. 7, 2008; title from title screen. Includes bibliographical references (p. 125-132).

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Kumar, Pankaj. "Chaos in Pulsed Laminar Flow." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/39260.

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Fluid mixing is a challenging problem in laminar flow systems. Chaotic advection can play an important role in enhancing mixing in such flow. In this thesis, different approaches are used to enhance fluid mixing in two laminar flow systems. In the first system, chaos is generated in a flow between two closely spaced parallel circular plates by pulsed operation of fluid extraction and reinjection through singularities in the domain. A singularity through which fluid is injected (or extracted) is called a source (or a sink). In a bounded domain, one source and one sink with equal strength operate together as a source-sink pair to conserve the fluid volume. Fluid flow between two closely spaced parallel plates is modeled as Hele-Shaw flow with the depth averaged velocity proportional to the gradient of the pressure. So, with the depth-averaged velocity, the flow between the parallel plates can effectively be modeled as two-dimensional potential flow. This thesis discusses pulsed source-sink systems with two source-sink pairs operating alternately to generate zig-zag trajectories of fluid particles in the domain. For reinjection purpose, fluid extracted through a sink-type singularity can either be relocated to a source-type one, or the same sink-type singularity can be activated as a source to reinject it without relocation. Relocation of fluid can be accomplished using either â first out first inâ or â last out first inâ scheme. Both relocation methods add delay to the pulse time of the system. This thesis analyzes mixing in pulsed source-sink systems both with and without fluid relocation. It is shown that a pulsed source-sink system with â first out first inâ scheme generates comparatively complex fluid flow than pulsed source-sink systems with â last out first inâ scheme. It is also shown that a pulsed source-sink system without fluid relocation can generate complex fluid flow. In the second system, mixing and transport is analyzed in a two-dimensional Stokes flow system. Appropriate periodic motions of three rods or periodic points in a two-dimensional flow are determined using the Thurston-Nielsen Classification Theorem (TNCT), which also predicts a lower bound on the complexity generated in the fluid flow. This thesis extends the TNCT -based framework by demonstrating that, in a perturbed system with no lower order fixed points, almost invariant sets are natural objects on which to apply the TNCT. In addition, a method is presented to compute line stretching by tracking appropriate motion of finite size rods. This method accounts for the effect of the rod size in computing the complexity generated in the fluid flow. The last section verifies the existence of almost invariant sets in a two-dimensional flow at finite Reynolds number. The almost invariant set structures move with appropriate periodic motion validating the application of the TNCT to predict a lower bound on the complexity generated in the fluid flow.
Ph. D.

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22

Samadi, Reza. "Compaction, flow and mechanical properties in lap joints for large multilayer VARTM preforms." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27554.

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Reinforcement preforms for the vacuum assisted resin transfer moulding (VARTM) manufacturing of large composite parts are made from different layers where presence of double curvature and varying fibre orientation imposes the use of superimposed lap joints. A series of tests were conducted to investigate the compaction of jointed preforms, flow through jointed preforms and the structural behaviour of composite parts featuring superimposed lap joints. A variety of lap joint configurations was investigated, characterized by specific values of overlap length, OL, horizontal distance between joints, HD, and number of immediately superimposed joints, NS, for a random matt and a woven reinforcement. The compaction of reinforcements was evaluated using a novel thickness measurement system for preforms. The thickness measurement system utilizes Hall effect sensors. The local fibre volume fraction, vf, was derived from the readings of Hall effect sensors positioned at selected locations above the jointed preforms. Different vf values were observed around joints; consequently, simulations of the manufacturing and performance of jointed composite parts must feature variable vf at the joints. The effective permeability to resin of jointed preforms parallel to the joints was investigated. The flow of resin in the preform was different from that in un-cut preforms. Specimens cut from cured panels were tested in four-point bending tests based on ASTM standard D790-03. The structural stiffness, maximum flexural stress and failure mode of specimens, were investigated. The structural stiffness and failure mode followed clear trends, while the maximum flexural stress was affected by local stress concentration at the joints. It is concluded that the presence of lap joints in VARTM preforms changes the behaviour during manufacturing and in service. This should be considered in design of parts and simulation of VARTM manufacturing.

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23

Hussain, Amer. "A Numerical Study of Compressible Lid Driven Cavity Flow with a Moving Boundary." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2155.

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A two-dimensional (2-D), mathematical model is adopted to investigate the development of circulation patterns for compressible, laminar, and shear driven flow inside a rectangular cavity. The bottom of the cavity is free to move at a specified speed and the aspect ratio of the cavity is changed from 1.0 to 1.5. The vertical sides and the bottom of the cavity are assumed insulated. The cavity is filled with a compressible fluid with Prandtl number, Pr =1. The governing equations are solved numerically using the commercial Computational Fluid Dynamics (CFD) package ANSYS FLUENT 2015 and compared with the results for the primitive variables of the problem obtained using in house CFD code based on Coupled Modified Strongly Implicit Procedure (CMSIP). The simulations are carried out for the unsteady, lid driven cavity flow problem with moving boundary (bottom) for different Reynolds number, Mach numbers, bottom velocities and high initial pressure and temperature.

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24

Fenzi, Robin. "Numerical simulations of viscoelastic tridimensional lid-driven cavity flows." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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Much is known about the dynamics of viscous Newtonian fluids in the classical “lid driven cavity” problem. However, little is known about the corresponding motion of viscoelastic fluids. The aim of this work is to study qualitatively and quantitatively the dynamics of viscoelastic flows for three different Deborah numbers in a tridimensional cavity. The so called “log-conformation formulation” made available by rheoTool for the OpenFOAM software is used to research the onset of elastic instabilities as an effect of viscoelasticity. The results obtained are presented through flow visualization and stress profiles. The symmetry observed in the velocity field of viscous Newtonian cavity flows at negligible Reynolds number is broken. The primary vortex centre shift progressively upstream with increasing Deborah number. The flow remains stable and two-dimensional with increasing Deborah number and no elastic instabilities appear. Upon the cessation of the moving wall motion, a pronounced elastic recoil is observed which leads to a rapid reversal in the recirculation direction. The elastic recoil subsequently decays through viscous dissipative effects.

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25

Al-Taweel, Ahmed Baqer. "Development of multiphase flow metering set-up utilizing coriolis meters." Dhahran, Saudi Arabia : King Fahd University of Petroleum and Minerals, 1997. http://library.kfupm.edu.sa/lib-downloads/1387233.pdf.

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26

Niimi, Tomohide, Hideo Mori, Kazuki Okabe, Yusuke Masai, and Mashio Taniguchi. "ANALYSES OF FLOW FIELD STRUCTURES AROUND LINEAR-TYPE AEROSPIKE NOZZLES USING LIF AND PSP." IEEE, 2003. http://hdl.handle.net/2237/7168.

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27

Yamashita, H., N. Hayashi, M. Ozeki, and K. Yamamoto. "Burning velocity and OH concentration in premixed combustion." Elsevier, 2009. http://hdl.handle.net/2237/20032.

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28

Alméras, Élise. "Étude des propriétés de transport et de mélange dans les écoulements à bulles." Thesis, Toulouse, INPT, 2014. http://www.theses.fr/2014INPT0115/document.

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Les réacteurs chimiques impliquant une phase liquide et une phase gazeuse sont couramment utilisés dans l'industrie pétrochimique et biologique car les écoulements à bulles ont de très bonnes propriétés de transfert et de mélange. Cela permet de mêler intimement différents composés et d'optimiser les réactions chimiques. Néanmoins, les mécanismes et les phénomènes mis en jeu dans le mélange au sein d'un écoulement à bulles restent encore mal connus. Ce travail a donc consisté à identifier les différents mécanismes de mélange en écoulement à bulles pour réviser le modèle physique de transport des espèces chimiques. Afin de distinguer et séparer les différents mécanismes, le mélange d'un traceur passif a été étudié dans différentes configurations expérimentales. Premièrement, l'étude du mélange dans un écoulement à bulles fortement confiné dans une cellule de Hele-Shaw a permis de mettre en évidence le mélange par capture du traceur dans les sillages. Ce mécanisme de mélange, fortement intermittent et convectif, s'est révélé être incompatible avec un processus purement diffusif. Deuxièmement, l'étude du mélange dans un essaim de bulles homogène tridimensionnel a été entreprise. Au contraire du cas confiné, le mélange, qui est causé par l'agitation induite par les bulles dans le liquide, est bien de nature diffusive. Nous avons donc pu mesurer les coefficients de diffusion effectifs en fonction de la fraction volumique de gaz. Ces coefficients sont différents dans les directions verticale et horizontale, ce qui traduit le caractère anisotrope du mélange. De plus, ils deviennent constants au-delà d'une certaine valeur de fraction volumique. Pour finir, nous avons considéré le mélange dans un essaim inhomogène de bulles, où se développe une boucle de recirculation du liquide. Dans le cas d'une recirculation modérée, la dispersion du traceur peut être estimée en combinant le mélange résultant de l'agitation des bulles avec l'advection par le mouvement moyen du fluide
Bubble columns are commonly used for chemical processes because of their good mixing and transfer capabilities. This work aims at understanding and modelling the mixing induced by bubbles. In order to distinguish the differents mixing mechanisms, the dispersion of a low-diffusive scalar has been investigated in various experimental configurations. The first one is a bubbly flow in a Hele-Shaw cell where the confinement prevents from the developpement of turbulence. In this case, the mixing is controlled by the capture and the transport by the bubble wakes. This mechanism, which cannot be described by an effective diffusivity, has been modelled by considering the intermittent transport of finite volumes of dye. The second configuration is a homogeneous swarm of rising bubbles where the mixing results from the dispersion by the bubble-induced turbulence. It can therefore be modelled by an anistropic effective diffusivity, which becomes independent of the gas volume fraction beyond a certain value. Finally, an inhomogenous bubbly flow, where a liquid recirculation loop is present, has been considered. In the case of a moderate inhomogeneity, shear induced-turbulence is not generated by the gradients of the mean flow and the mixing can be modelled by the sum of the bubble-induced dispersion and the advection by the mean flow

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Freibert, Marco [Verfasser], and Vicente [Akademischer Betreuer] Cortés-Suárez. "Geometric structures on Lie algebras and the Hitchin flow / Marco Freibert. Betreuer: Vicente Cortés-Suárez." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2013. http://d-nb.info/1036729400/34.

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Freibert, Marco [Verfasser], and Vicente [Akademischer Betreuer] Cortés. "Geometric structures on Lie algebras and the Hitchin flow / Marco Freibert. Betreuer: Vicente Cortés-Suárez." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2013. http://d-nb.info/1036729400/34.

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31

Kaur, Amandeep. "Analytic and numerical aspects of isospectral flows." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/270631.

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In this thesis we address the analytic and numerical aspects of isospectral flows. Such flows occur in mathematical physics and numerical linear algebra. Their main structural feature is to retain the eigenvalues in the solution space. We explore the solution of Isospectral flows and their stochastic counterpart using explicit generalisation of Magnus expansion. \par In the first part of the thesis we expand the solution of Bloch--Iserles equations, the matrix ordinary differential system of the form $ X'=[N,X^{2}],\ \ t\geq0, \ \ X(0)=X_0\in \textrm{Sym}(n),\ N\in \mathfrak{so}(n), $ where $\textrm{Sym}(n)$ denotes the space of real $n\times n$ symmetric matrices and $\mathfrak{so}(n)$ denotes the Lie algebra of real $n\times n$ skew-symmetric matrices. This system is endowed with Poisson structure and is integrable. Various important properties of the flow are discussed. The flow is solved using explicit Magnus expansion and the terms of expansion are represented as binary rooted trees deducing an explicit formalism to construct the trees recursively. Unlike classical numerical methods, e.g.\ Runge--Kutta and multistep methods, Magnus expansion respects the isospectrality of the system, and the shorthand of binary rooted trees reduces the computational cost of the exponentially growing terms. The desired structure of the solution (also with large time steps) has been displayed. \par Having seen the promising results in the first part of the thesis, the technique has been extended to the generalised double bracket flow $ X^{'}=[[N,X]+M,X], \ \ t\geq0, \ \ X(0)=X_0\in \textrm{Sym}(n),$ where $N\in \textrm{diag}(n)$ and $M\in \mathfrak{so}(n)$, which is also a form of an Isospectral flow. In the second part of the thesis we define the generalised double bracket flow and discuss its dynamics. It is noted that $N=0$ reduces it to an integrable flow, while for $M=0$ it results in a gradient flow. We analyse the flow for various non-zero values of $N$ and $M$ by assigning different weights and observe Hopf bifurcation in the system. The discretisation is done using Magnus series and the expansion terms have been portrayed using binary rooted trees. Although this matrix system appears more complex and leads to the tri-colour leaves; it has been possible to formulate the explicit recursive rule. The desired structure of the solution is obtained that leaves the eigenvalues invariant in the solution space.

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32

Centeno, Luis E. "Application of demand flow technology to cable assembly production line." Online version, 2002. http://www.uwstout.edu/lib/thesis/2002/2002centenol.pdf.

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Peterson, Lloyd G. "Lean/flow design event a manufacturing cost reduction case study /." Online version, 2004. http://www.uwstout.edu/lib/thesis/2004/2004petersonl.pdf.

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34

Zanghi, Eric (Eric James). "Analysis of oil flow mechanisms in internal combustion engines via high speed Laser Induced Fluorescence (LIF) spectroscopy." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92107.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 86-88).
Automotive manufacturers have a significant challenge ahead of them with new more stringent regulations for exhaust emissions and fuel economy being implemented in the coming future. To make an impact on current emissions and fuel economy, new advanced analytical methods, such as high speed Laser Induced Fluorescence (LIF), must be employed when studying an internal combustion engine. With lubrication in the piston-ring pack assembly being one of the most significant contributors of oil consumption, it directly impacts exhaust emissions as well as indirectly affect fuel economy. High speed LIF spectroscopy has the ability to observe any oil flow mechanisms inside the cylinder which may be directly correlated to performance or oil consumption. This study intended to be a development process of taking a slower sampling LIF system and creating the high speed LIF for more advanced diagnostic purposes. Significant flaws were observed in the original LIF system, such as extremely low temporal resolution and error caused by temperature dependence in the dyes used for LIF spectroscopy. To develop this system, new lasers, optics, and cameras had to be tested to find which gave the best possible images. The implementation of the high speed camera fundamentally changed the observations and allowed for precise analysis of any and all oil flow mechanisms present in an internal combustion engine. While testing the system, old phenomena that had been previously documented allowed for a pseudo-calibration in which confirmation could be made that the system is working in a similar manner to the original system. Slow and fast cavitation effects were clearer than previous videos as well as the bridging effects which can be so detrimental to oil consumption. Even new phenomena were documented which provided much more work to be done in the future to truly understand and analyze these new oil mechanisms. This research is very much a diagnostic proof of concept such that others may be able to build such an analytical tool to understand oil flow mechanisms inside and internal combustion engine to better the fuel economy or exhaust emissions. Future experiments will truly determine the limit of what the system can do and how it can impact future engine designs.
by Eric Zanghi.
S.M.

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Al-Muraikhi, Ahmed J. "Evaluation of vertical multiphase flow correlations for Saudi Arabian field conditions." Dhahran, Saudi Arabia : King Fahd University of Petroleum and Minerals, 1989. http://library.kfupm.edu.sa/lib-downloads/1381127.pdf.

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Nichols, Andrew. "Free surface dynamics in shallow turbulent flows." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/7345.

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This study aimed to understand the processes that govern free surface behaviour in depth-limited turbulent flows. Experimental data has shown that the turbulence properties at a point near the free surface relate directly to the properties of the free surface pattern. This would suggest a direct linkage between the free surface and the underlying turbulence field, but this cannot be true since the free surface pattern is strongly dynamic while the sub-surface turbulence field is relatively persistent. An oscillatory spatial correlation function was derived which explains the de-linkage, showing that the turbulence-generated surface pattern periodically inverts as it advects downstream. A model was developed, which shows that the observed free surfaces can be considered as an ensemble of overlapping but behaviourally independent oscillons. These are shown to influence a zone of fluid beneath the surface and invert at a frequency which is a function of the root-mean-square roughness height of the free surface. The spatial frequency of free surface oscillation relates strongly to the spatial frequency of turbulent structures, suggesting that the oscillon motion may form the trigger for near-bed bursting events. Given these relationships, it is proposed that measurement of the free surface behaviour may allow remote measurement of flow conditions. An acoustic wave probe was developed, which is able to remotely recover the key features of the water surface pattern. An array of such probes is proposed for the accurate measurement of temporal and spatial properties of turbulent free surfaces and hence the underlying bulk flow conditions.

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Yang, Ping. "Particle Vaporization Velocimetry and Quantitative Soot Concentration Measurement in Sooty Flows." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19843.

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Soot is a combustion generated pollutant that is both a direct risk to human health and a contributing source to global environmental change. Soot can also be a controlling factor in heat transfer inside combustion systems. Thus there is a growing interest in being able to measure soot and understand its production in practical, turbulent combustion environments. Therefore, the specific objectives of this research work were: (1) developing a way to measure velocity of sooty regions that is compatible with existing methods for measuring temporally and spatially resolved soot concentration fields and (2) using these methods to make quantitative measurements of soot in an unsteady, turbulent-like combustor. The Particle Vaporization Velocimetry (PVV) technique was developed and is compatible with Laser Induced Incandescence (LII), a soot concentration measurement approach. PVV is a flow tagging approach, where a high intensity laser (~2-3 J/cm2) is used to vaporize a small region in the soot field. This approach was demonstrated to produce a long lasting and easily readable flow tag that allows for velocity measurements over a wide range of velocities. LII proved to be the best method for detection the motion of the tag after a fixed delay. PVV and LII were used to measure velocity and two-dimensional soot concentration fields in an acoustically excited burner. In addition, images of soot luminosity were obtained. Both laminar and transitional acetylene diffusion flames were studied. The results reveal that strong acoustic forcing can significantly reduce total flame soot, as well as maximum soot concentrations, while simultaneously increasing the average soot temperature. The influence of acoustically generated vortices on soot formation was studied, and soot and products mixture mostly likely dominant high soot concentration regions. Eventually, these mixtures will be propagated downstream and oxidized as a diffusion flame.

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Lin, Shy-Yea [Verfasser]. "Coherent structures and rotational effects on the flow over spinners of horizontal axis wind turbines / Shy-Yea Lin." Hannover : Technische Informationsbibliothek (TIB), 2016. http://d-nb.info/1122591918/34.

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Green, Adam. "Structure and Dynamics of Two Flow Fields Used for Particle Deposition onto and Removal from a Substrate." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/554.

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A series of experimental studies was performed to investigate two separate fluid impingement flow systems intended for removal of particles from a surface or deposition of particles onto a surface. One of these flow systems is generated using a nozzle that incorporates both tilted jets and suction to create what we call a "bounded vortex flow", consisting of an annular swirling jet and a wall-normal vortex with axial upflow into a suction outlet. The other flow system is generated by a combination of acoustic streaming and substrate heating from an ultrasonic source. The primary methods used in the study for flow field measurements included laser-induced fluorescence (LIF) and particle-image velocimetry (PIV). Thermocouples are utilized for gathering temperature information from the ultrasonic induced flow. For the bounded vortex flow, different jet/suction flow rates and different nozzle-substrate separation distances were examined. In the acoustic-generated flow system, different acoustic intensities and transducer-substrate separation distances and different choices of substrate material were examined. Both flow systems achieve high levels of shear stress on the impingement surface via a combination of flow oriented toward and/or away from the surface and via formation of vortex structures near the impingement surface. In the bounded flow configuration, the vortex flow is oriented with axis normal to the impingement surface, whereas in the acoustic-generated flow a series of vortex rings form with axes parallel to the impingement surface. For both flow fields, conditions are observed with high impingement surface shear stress that are well suited to particle removal from the impingement surface. However, as the variables controlling the flows are varied, other conditions are observed in which the flow fields become unstable, leading to oscillatory flows that generally have much smaller shear stress values on the impingement surface. The rate of fluid mixing, as characterized by upward and downward flows normal to the impingement surface, is also generally decreased after these flow transitions have occurred, implying that the unstable flows will be less suited for both particle deposition on and particle removal from the impingement surface.

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Xu, Ying. "TWO-DIMENSIONAL SIMULATION OF SOLIDIFICATION IN FLOW FIELD USING PHASE-FIELD MODEL|MULTISCALE METHOD IMPLEMENTATION." Lexington, Ky. : [University of Kentucky Libraries], 2006. http://lib.uky.edu/ETD/ukymeen2006d00524/YingXu_Dissertation_2006.pdf.

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Thesis (Ph. D.)--University of Kentucky, 2006.
Title from document title page (viewed on January 25, 2007). Document formatted into pages; contains: xiii, 162 p. : ill. (some col.). Includes abstract and vita. Includes bibliographical references (p. 151-157).

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Santos, Daniel Dall'Onder dos. "Modelagem mecânica e investigação numérica de escoamentos de fluidos SMD empregando um método multi-campos de galerkin mínimos-quadrados." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/27259.

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A maioria dos líquidos encontrados na natureza são não-Newtonianos e o estudo do seu comportamento tem uma importância significante em diferentes áreas da engenharia. Entre eles, uma larga classe de materiais que exibem pequena ou nenhuma deformação quando sujeitos a um nível de tensões inferiores a uma tensão limite de escoamento – chamado de comportamento viscoplástico. A presente Dissertação tem como objetivo o estudo numérico de escoamentos bidimensionais em regime permanente de fluidos viscoplásticos não-lineares em uma cavidade forçada. O modelo mecânico é definido pelas equações de conservação de massa e de balanço de momentum acopladas ao modelo viscoplástico recentemente introduzido por Souza Mendes e Dutra – SMD – e é aproximado por um método de elementos finitos multi-campos estabilizado baseado na metodologia de Galerkin mínimos-quadrados que possui como variáveis primais os campos de tensão-extra, velocidade e pressão. As condições de compatibilidade entre os subespaços de elementos finitos para tensão-extra-velocidade e velocidade-pressão são violadas, permitindo assim a utilização de interpolações de igual ordem. O método estabilizado foi implementado no código de elementos finitos para fluidos não-Newtonianos em desenvolvimento no Laboratório de Mecânica dos Fluidos Aplicada e Computacional (LAMAC) da UFRGS. Em diversos trabalhos encontrados na literatura, a superfície de escoamento do material é definida como a região onde o módulo da tensão-extra é igual à tensão limite de escoamento. É mostrado nesta Dissertação que esta metodologia pode conduzir à alguns erros, dado ao grande aumento experimentado pela taxa de cisalhamento em uma pequena faixa de tensões próximas à tensão limite de escoamento. Assim, foi adotada outra metodologia, definindo a superfície de escoamento como a linha onde a taxa de cisalhamento é igual a um valor dado pela relação de parâmetros reológicos do fluido, especificamente a tensão limite de escoamento e a viscosidade Newtoniana para baixas taxas de cisalhamento. Nas simulações numéricas realizadas, o número de salto, J, o coeficiente de power-law, n, e a vazão adimensional, U*, são variados de forma a avaliar de que modo influenciam na dinâmica de escoamentos viscoplásticos. Os resultados obtidos estão de acordo com a literatura e atestam a estabilidade da formulação empregada.
Non-Newtonian fluids are the majority of liquids found on the nature and the study of their behavior has a significant importance on different areas of engineering. Among them, there is a wide class of materials that exhibits little or no deformation when subjected to a stress level behind an apparent yield stress – called the viscoplastic behavior. The present thesis aimed to a numerical study of two dimensional steady state laminar flows of non-linear viscoplastic fluids in a lid-driven cavity. The mechanical model was defined by the mass conservation and momentum balance equations coupled to the recently introduced Souza Mendes and Dutra – SMD – viscoplastic model and has been approximated by a stabilized multi-field finite element method based on the Galerkin least-squares methodology, having as primal variables the extra-stress, velocity and pressure fields. In this way, the compatibility conditions between the extra-stressvelocity and pressure-velocity (Babuška-Brezzi condition) finite element subspaces are violated, allowing to use equal-order finite element interpolations. The stabilized method has been implemented in the finite element code for non-Newtonian fluids under development at the Laboratory of Applied and Computational Fluid Mechanics (LAMAC) of UFRGS. In several works found on the literature, the yield surface of the material is defined as the region where the stress modulus is equal to the yield stress. Is shown in this work that this methodology can lead to some errors, due to the large strain rate increasing in a small range of values of stress on the vicinity of the yield stress. Therefore, it was adopted another approach, defining the yield surface as the line where the strain rate is equal to a value given by the relation of the rheological parameters of the fluid, namely the yield stress and the viscosity at low shear rates. In the performed numerical simulations, the jump number, J, the the power-law coefficient, n,and the non-dimensional flow rate, U*, are ranged in order to evaluate how they the influence on the viscoplastic fluid dynamics have been investigated. All results found were in accordance with the affine literature and attests the good stability features of the formulation.

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Нагірний, Микола Михайлович, and Mykola Nagirny. "Дослідження системи транспортної логістики підприємства." Master's thesis, Тернопільський національний технічний університет імені Івана Пулюя, 2020. http://elartu.tntu.edu.ua/handle/lib/33994.

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Роботу виконано на кафедрі автомобілів Тернопільського національного технічного університету імені Івана Пулюя Міністерства освіти і науки України. Захист відбудеться 22 грудня 2020 р. о 10:00 годині на засіданні екзаменаційної комісії № 20 у Тернопільському національному технічному університеті імені Івана Пулюя за адресою: 46001, м. Тернопіль, вул. Текстильна, 28, навчальний корпус № 9.
Нагірний М. М. Дослідження системи транспортної логістики підприємства – Рукопис. Кваліфікаційна робота на здобуття освітнього ступеня магістр за спеціальністю 275.03 – транспортні технології (на автомобільному транспорті). – Тернопільський національний технічний університет імені Івана Пулюя, – Тернопіль, 2020. В першому розділі розглянуто теоретичні основи управління транспортними потоками підприємства, зокрема, поняття та структура систем управління логістичними транспортними потоками підприємств, напрями удосконалення системи управління транспортними потоками. В другому розділі проведено дослідження процесу управління транспортними потоками на підприємстві, проаналізовано показники діяльності підприємства, визначено чинники, що впливають на процес транспортування, проаналізовано діючу системи управління транспортними потоками підприємства. В третьому розділ розроблено заходи з удосконалення системи управління логістичними транспортними потоками підприємства, розроблено методику оцінки систем управління логістичними транспортними потоками та заходи з оптимізації маршрутів руху транспортних засобів, розраховано економічну ефективність. В четвертому розділі розглянуто заходи з охорони праці та безпеки життєдіяльності на транспорті. Дипломна робота викладена на 76 сторінках і містить 12 таблиць та 10 рисунків. Робота складається з вступу, 4 розділів і висновків. Для написання дипломної роботи було використано 29 літературних джерел.
ВСТУП 7 1. ТЕОРЕТИЧНИЙ РОЗДІЛ. ТЕОРЕТИЧНІ ОСНОВИ УПРАВЛІННЯ ЛОГІСТИЧНИМИ ТРАНСПОРТНИМИ ПОТОКАМИ ПІДПРИЄМСТВ 9 1.1. Поняття і структура системи управління логістичними потоками підприємства 9 1.2. Класифікація транспортних потоків в логістиці 20 1.3. Напрямки вдосконалення системи управління транспортними потоками 24 2. АНАЛІТИКО-ДОСЛІДНИЦЬКИЙ РОЗДІЛ. РОЗДІЛ ДОСЛІДЖЕННЯ ПРОЦЕСУ УПРАВЛІННЯ ТРАНСПОРТНИМИ ПОТОКАМИ НА ПІДПРИЄМСТВІ 28 2.1. Аналіз показників діяльності 28 2.2. Оцінка чинників, що впливають на процес транспортування 32 2.3. Аналіз діючої системи управління транспортними потоками 38 3. ПРОЕКТНО-РЕКОМЕНДАЦІЙНИЙ РОЗДІЛ. РОЗРОБКА ЗАХОДІВ З УДОСКОНАЛЕННЯ СИСТЕМИ УПРАВЛІННЯ ЛОГІСТИЧНИМИ ПОТОКАМИ ПІДПРИЄМСТВА 47 3.1. Розробка методики оцінки системи управління логістичними потоками підприємства 37 3.2. Розробка заходів оптимізації маршруту руху транспортних засобів 47 3.3. Розрахунок економічної ефективності 54 4. ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ 67 4.1. Охорона праці на автомобільному транспорті. Рекомендації 4.2. Безпека життєдіяльності та система управління безпекою дорожнього руху 67 69 ВИСНОВКИ 72 СПИСОК ВИКОРИСТАНОЇ ЛІТЕРАТУРИ 74

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Zavareh, Alireza. "Analytical and Numerical methods for a Mean curvature flow equation with applications to financial Mathematics and image processing." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2132.

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This thesis provides an analytical and two numerical methods for solving a parabolic equation of two-dimensional mean curvature flow with some applications. In analytical method, this equation is solved by Lie group analysis method, and in numerical method, two algorithms are implemented in MATLAB for solving this equation. A geometric algorithm and a step-wise algorithm; both are based on a deterministic game theoretic representation for parabolic partial differential equations, originally proposed in the genial work of Kohn-Serfaty [1].
+46-767165881

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Lee, Heon Ju. "Application of a ratiometric laser induced fluorescence (LIF) thermometry for micro-scale temperature measurement for natural convection flows." Texas A&M University, 2003. http://hdl.handle.net/1969.1/1128.

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A ratiometric laser induced fluorescence (LIF) thermometry applied to micro-scale temperature measurement for natural convection flows. To eliminate incident light non-uniformity and imperfection of recording device, two fluorescence dyes are used: one is temperature sensitive fluorescence dye (Rhodamine B) and another is relatively temperature insensitive fluorescence dye (Rhodamine 110). Accurate and elaborate calibration for intensity ratio verses temperature obtained using an isothermal cuvette, which was controlled by two thermo-bathes. 488nm Ar-ion laser used for incident light and two filter sets used for separating each fluorescence emission. Thermally stratified filed of 10mm channel with micro-scale resolution measured within 1.3?C uncertainty of liner prediction with 23?m x 23?m spatial resolution. Natural convection flows at 10mm channel also observed. The several difficulties for applying to heated evaporating meniscus were identified and a few resolutions were suggested.

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Bergamo, Leandro Fernandes. "Instabilidade hidrodinâmica linear do escoamento compressível em uma cavidade." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18148/tde-28052014-164324/.

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Os mecanismos de instabilidade hidrodinâmica têm um papel importante no processo da transição do escoamento de laminar para turbulento. A análise da instabilidade hidrodinâmica em uma cavidade com tampa deslizante foi realizada através da decomposição em modos globais (biglobal) para avaliar o efeito da compressibilidade neste fenômeno. O escoamento base foi obtido através de simulação numérica direta (DNS). Para tal, foi desenvolvido um código DNS compressível com discretização espacial por diferenças finitas compactas de alta resolução espectral e capacidade de processamento paralelo, com um método de decomposição de domínio que mantém a precisão das diferenças finitas compactas. O escoamento base é usado para montar o problema de autovalor oriundo das equações de Navier-Stokes linearizadas para a perturbação, discretizadas por diferenças finitas explícitas. O uso de diferenças finitas em conjunto com a implementação em matrizes esparsas reduz sensivelmente o uso de memória. Através do algoritmo de Arnoldi, a ordem do problema de autovalor é reduzida e os autovalores de interesse são recuperados. Os resultados indicam o efeito estabilizante da compressibilidade nos modos dominantes da cavidade e revelam modos inerentes ao escoamento compressível, para os quais a compressibilidade tem efeito desestabilizante. Dentre estes modos compressíveis, estão presentes modos de propagação sonora em dutos e modos relacionados à geração de som na cavidade.
Hydrodynamic instability mechanisms play an important role in laminar to turbulent transition. Hydrodynamic instability analysis of a lid-driven cavity flow was performed by global mode decomposition (biglobal) to evaluate compressibility effects on this phenomenon. The basic flow was calculated by direct numerical simulation (DNS). A compressible DNS code was developed with spectral-like compact finite difference spatial discretization. The code allows parallel processing with a domain decomposition method that preserves the compact finite difference accuracy. The basic flow is used to form the eigenvalue problem associated to the linear Navier- Stokes equations for the perturbation, which were discretized by an explicit finite difference scheme. The combination of sparse matrix techniques and finite difference discretization leads to a significant memory reduction. The order of the eigenvalue problem was reduced using the Arnoldi algorithm and the eigenvalues of interest were calculated. Results show the stabilizing effect of compressibility on the leading modes and reveal some modes intrinsic to compressible flow, for which compressibility has a destabilizing effect. Among these compressible modes, there are some related to sound propagation in ducts and to sound generation inside the cavity.

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Lin, Ming-Yi [Verfasser], and Reinhard [Akademischer Betreuer] Genzel. "Gas flows and stars in nuclear regions of nearby seyfert galaxies / Ming-Yi Lin ; Betreuer: Reinhard Genzel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2017. http://d-nb.info/1142787400/34.

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Думанський, Віталій Олегович, and Vitalii Dumanskyi. "Дослідження безпеки дорожнього руху на окремих ділянках вулично-дорожньої мережі обласного центру." Bachelor's thesis, Тернопільський національний технічний університет імені Івана Пулюя, 2021. http://elartu.tntu.edu.ua/handle/lib/35618.

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Роботу виконано на кафедрі автомобілів Тернопільського національного технічного університету імені Івана Пулюя Міністерства освіти і науки України. Захист відбудеться 25 червня 2021 р. о 10:00 годині на засіданні екзаменаційної комісії № 19 у Тернопільському національному технічному університеті імені Івана Пулюя за адресою: 46001, м. Тернопіль, вул. Текстильна, 28, навчальний корпус № 9.
Думанський В.О. Дослідження безпеки дорожнього руху на окремих ділянках вулично-дорожньої мережі обласного центру — Рукопис. Кваліфікаційна робота на здобуття освітнього ступеня бакалавр за спеціальністю 275 Транспортні технології (на автомобільному транспорті). — Тернопільський національний технічний університет імені Івана Пулюя, — Тернопіль, 2021. У кваліфікаційній роботі проведено дослідження елементів вулично-дорожньої мережі м. Тернопіль, та запропоновано організаційні заходи, які спрямовані на підвищення показників рівня безпеки для учасників дорожнього руху.
ВСТУП 5 РОЗДІЛ І АНАЛІЗ СТАНУ БЕЗПЕКИ ДОРОЖНЬОГО РУХУ НА ДОСЛІДЖУВАНОМУ ПЕРЕХРЕСТІ 8 1.1 Сучасний стан безпеки дорожнього руху 8 1.2 Основні чинники впливу на безпеку дорожнього руху 12 1.3 Встановлення місць (ділянок) концентрації дорожньо-транспортних пригод м. Тернопіль 15 1.4 Результати досліджень транспортних потоків на окремій ділянці вулично-дорожньої мережі 22 1.5 Аналіз дорожньої інфраструктури на ділянці концентрації ДТП 26 РОЗДІЛ II ЗАХОДИ ЩОДО ПІДВИЩЕННЯ БЕЗПЕКИ ДОРОЖНЬОГО РУХУ НА ДОСЛІДЖУВАНІЙ ДІЛЯНЦІ ВУЛИЧНО-ДОРОЖНЬОЇ МЕРЕЖІ 28 2.1 Підвищення якості інформаційного впливу на учасників дорожнього руху 28 2.1.1. Інформаційне табло для водіїв 29 2.1.2 Зменшення кількості зовнішньої реклами 34 2.1.3 Заміна дорожніх знаків, що не відповідають ДСТУ 4100-2014 36 2.2 Облаштування пішохідних переходів на аварійно-небезпечних ділянках 37 2.3 Зниження інтенсивності руху на ділянках з підвищеною концентрацією ДТП 40 2.4 Моделювання стану безпеки руху у місті Тернопіль 41 РОЗДІЛ ІІІ ОХОРОНА ПРАЦІ ТА БЕЗПЕКА ЖИТТЄДІЯЛЬНОСТІ 49 3.1 Вплив дорожньо-транспортних ситуацій на безпеку людини 49 3.2 Стомлення, його причини та психофізіологічні механізми 50 ЗАГАЛЬНІ ВИСНОВКИ 52 ПЕРЕЛІК ПОСИЛАНЬ 53

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Мудра, Ілона Олегівна, and Ilona Mudra. "Аналіз режимів регулювання транспортних потоків на вулично-дорожній мережі." Bachelor's thesis, Тернопільський національний технічний університет імені Івана Пулюя, 2021. http://elartu.tntu.edu.ua/handle/lib/35622.

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Роботу виконано на кафедрі автомобілів Тернопільського національного технічного університету імені Івана Пулюя Міністерства освіти і науки України. Захист відбудеться 25 червня 2021 р. о 10:00 годині на засіданні екзаменаційної комісії № 19 у Тернопільському національному технічному університеті імені Івана Пулюя за адресою: 46001, м. Тернопіль, вул. Текстильна, 28, навчальний корпус № 9.
Мудра І.О. Аналіз режимів регулювання транспортних потоків на вулично-дорожній мережі — Рукопис. Кваліфікаційна робота на здобуття освітнього ступеня бакалавр за спеціальністю 275 Транспортні технології (на автомобільному транспорті). — Тернопільський національний технічний університет імені Івана Пулюя, — Тернопіль, 2021. У кваліфікаційній роботі проведено дослідження закономірності впливу технічних засобів організації дорожнього руху на інтенсивність транспортних потоків та затримки транспортних засобів при проїзді ділянок вулично-дорожньої мережі.
ВСТУП 6 РОЗДІЛ 1. АНАЛІЗ МЕТОДІВ ОПТИМІЗАЦІЇ ПРОЇЗДУ РЕГУЛЬОВАНИХ ПЕРЕХРЕСТЬ ТА ЇХ ПЛАНУВАЛЬНІ ХАРАКТЕРИСТИКИ 7 1.1 Вплив планувальних особливостей вулично-дорожньої мережі на можливості застосування примусового регулювання 7 1.2 Методи та моделі розрахунку транспортних затримок на регульованих перехрестях 12 1.3 Характеристика та аналіз досліджуваної вулично-дорожньої мережі міста 13 1.4 Аналіз існуючого стану ОДР на окремих ділянках руху проспекту Миру 24 РОЗДІЛ 2 ФОРМУВАННЯ РАЦІОНАЛЬНИХ РЕЖИМІВ РЕГУЛЮВАННЯ ТРАНСПОРТНИХ ПОТОКІВ НА ВУЛИЧНО-ДОРОЖНІЙ МЕРЕЖІ 31 2.1 Теоретичні передумови розрахунку параметрів «Зеленої хвилі» 31 2.2 Результати розрахунку параметрів координованого світлофорного регулювання 35 РОЗДІЛ 3 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА ЖИТТЄДІЯЛЬНОСТІ 45 3.1 Основи безпеки дорожнього руху 45 3.2 Основні причини скоєння дорожньо-транспортних пригод та безпека учасників ДР 46 ЗАГАЛЬНІ ВИСНОВКИ 49 ПЕРЕЛІК ПОСИЛАНЬ 51

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Loiseau, Jean-Christophe. "Dynamics and global stability analysis of three-dimensional flows." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0016/document.

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Comprendre, prédire et finalement retarder la transition vers la turbulence dans les écoulements sont d'importants problèmes posés aux scientifiques depuis les travaux pionniers d'Osborne Reynolds en 1883. Ces questions ont été principalement adressées à l'aide de la théorie des instabilités hydrodynamiques. A cause des ressources informatiques limitées, les analyses de stabilité linéaire reposent essentiellement sur d'importantes hypothèses simplificatrices telles que celle d'un écoulement parallèle. Dans ce cadre, connu sous le nom de stabilité locale, seule la stabilité d'écoulement ayant un fort intérêt académique mais relativement peu d'applications pratiques a pu être étudiée. Néanmoins, au cours de la décennie passée, l'hypothèse d'écoulement parallèle a été relaxée au profit de celle d'un écoulement bidimensionnel conduisant alors à ce que l'on appelle la stabilité globale. Ce nouveau cadre permet alors d'étudier les mécanismes d'instabilité et de transition ayant lieu au sein d'écoulements plus réalistes. Plus particulièrement, la stabilité d'écoulements fortement non-parallèles pouvant présenter des décollements massifs, une caractéristique fréquente dans les écoulements d'intérêt industriel, peut maintenant être étudiée. De plus, avec l'accroissement constant des moyens de calcul et le développement de nouveaux algorithmes de recherche de valeurs propres itératifs, il est aujourd'hui possible d'étudier la stabilité d'écoulements pleinement tridimensionnels pour lesquels aucune hypothèse simplificatrice n'est alors nécessaire. Dans la continuité des travaux présentés par Bagheri et al. en 2008, le but de la présente thèse est de développer les outils nécessaires à l'analyse de la stabilité d'écoulements 3D. Trois écoulements ont été choisis afin d'illustrer les nouvelles capacités de compréhension apportées par l'analyse de la stabilité globale appliquée à des écoulements tridimensionnels réels : i) l'écoulement au sein d'une cavité entraînée 3D, ii) l'écoulement se développant dans un tuyau sténosé, et enfin iii) l'écoulement de couche limite se développant au passage d'une rugosité cylindrique montée sur une plaque plane. Chacun de ces écoulements a différentes applications pratiques allant d'un intérêt purement académique à une application biomédicale et aérodynamique. Ce choix d'écoulements nous permet également d'illustrer les différents aspects des outils développés au cours de cette thèse ainsi que les limitations qui leur sont inhérentes
Understanding, predicting and eventually delaying transition to turbulence in fluid flows have been challenging issues for scientists ever since the pioneering work of Osborne Reynolds in 1883. These problems have mostly been addressed using the hydrodynamic linear stability theory. Yet, due to limited computational resources, linear stability analyses have essentially relied until recently on strong simplification hypotheses such as the “parallel flow” assumption. In this framework, known as “local stability theory”, only the stability of flows with strong academic interest but limited practical applications can be investigated. However, over the course of the past decade, simplification hypotheses have been relaxed from the “parallel flow” assumption to a two-dimensionality assumption of the flow resulting in what is now known as the “global stability theory”. This new framework allows one to investigate the instability and transition mechanisms taking place in more realistic flows. More particularly, the stability of strongly non-parallel flows exhibiting separation, a common feature of numerous flows of practical interest, can now be studied. Moreover, with the continuous increase of computational power available and the development of new iterative eigenvalue algorithms, investigating the global stability of fully three-dimensional flows, for which no simplification hypothesis is necessary, is now feasible. Following the work presented in 2008 by Bagheri et al., the aim of the present thesis is thus to develop the tools mandatory to investigate the stability of 3D flows. Three flow configurations have been chosen to illustrate the new investigation capabilities brought by global stability theory when it is applied to realistic three-dimensional flows: i) the flow within a cuboid lid-driven cavity, ii) the flow within an asymmetric stenotic pipe and iii) the boundary layer flow developing over a cylindrical roughness element mounted on a flat plate. Each of these flows have different practical applications ranging from purely academic interests to biomedical and aerodynamical applications. They also allow us to put in the limelight different aspects and possible limitations of the various tools developed during this PhD thesis

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Дем'янюк, Тимофій Русланович, and Tymofii Demianiuk. "Розробка автоматизованої інформаційної системи надання послуг клієнтам будівельної компанії." Bachelor's thesis, Тернопіль, ТНТУ, 2021. http://elartu.tntu.edu.ua/handle/lib/35407.

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Роботу виконано на кафедрі ком’пютерно-інтегрованих технологій Тернопільського національного технічного університету імені Івана Пулюя Міністерства освіти і науки України Захист відбудеться 22 червня 2021 р. о 09 .00 годині на засіданні екзаменаційної комісії № 23 у Тернопільському національному технічному університеті імені Івана Пулюя за адресою: 46001, м. Тернопіль, вул.Руська, 56, навчальний корпус №1, ауд. 403
Дем’янюк Т.Р. Розробка автоматизованої інформаційної системи надання послуг клієнтам будівельної компанії. 151 – автоматизація та комп’ютерно-інтегровані технології. – Тернопільський національний технічний університет імені Івана Пулюя. – Тернопіль, 2021. У роботі було розроблено автоматизовану інформаційну систему для обслуговування клієнтів будівельної компанії. Було детально розглянуто структуру управління підприємством, описано його технічні можливості, побудовано структурно-функціональну діаграму організації бізнес-процесів підприємства. На основі аналізу вхідних даних було розглянуто існуючі засоби для побудови автоматизованих інформаційних систем. Для реалізації обрано оболонку 1С Підприємство. У роботі також було проаналізовано та вдосконалено усі процеси для прискорення виконання замовлення. Для цього було створено усі необхідні інструменти: форми для вводу інформації, підсистеми, загальні модулі, константи, довідники, звіти. Впровадження такої системи дозволяє значно скоротити затрати часу на створення документації, та оформлення замовлення, покращує контроль за його виконанням, підвищує захищеність інформації, та надає можливість оперативного контролю за усіма сферами діяльності. На основі згенерованих звітів є можливість аналізувати діяльність підприємства, що значно підвищує його мобільність.
Demianiuk Т. Development of an automatic information system of services providing to a building company clients. 151 - automation and computer integrated technologies. - Ivan Puliuyi Ternopil National Technical University. - Ternopil, 2021. An automated information system for customer service of a construction company was developed in the work. The structure of enterprise management was considered in detail, its technical possibilities were described, the structural-functional diagram of the organization of business processes of the enterprise was constructed. Based on the analysis of input data, the existing tools for building automated information systems were considered. The 1C Enterprise shell was chosen for implementation. The paper also analyzed and improved all processes to speed up order fulfillment. To do this, all the necessary tools were created: forms for entering information, subsystems, general modules, constants, directories, reports. The introduction of such a system significantly reduces the time spent on creating documentation and ordering, improves control over its implementation, increases the security of information, and provides the ability to quickly control all areas of activity. Based on the generated reports, it is possible to analyze the activities of the enterprise, which significantly increases its mobility.
ВСТУП 6 1. АНАЛІТИЧНА ЧАСТИНА 8 1.1. Організаційна структура управління підприємством та його характеристика 8 1.2 Опис інформаційного і технічного забезпечення підприємства, використовуваних функціональних можливостей 10 1.3 Структурно-функціональна діаграма організації бізнесу «Як є» і її опис 11 1.4 Аналіз існуючих розробок для автоматизації комплексу завдань. 17 2. ПРОЄКТНА ЧАСТИНА 21 2.1 Вибір комплексу задач автоматизації і характеристика існуючих бізнес-процесів. 21 2.2 Опис основних властивостей інформаційної системи для підприємства і обраного комплексу завдань. 23 2.3 Економічна сутність комплексу задач. 24 2.4 Вибір і обгрунтування стратегії автоматизації комплексу завдань. 26 2.5 Вибір і обгрунтування способу придбання інформаційної системи для автоматизації комплексу завдань 27 2.6. Розгорнута постановка мети, завдання і підзадач автоматизації. Аналіз плану «Як повинно бути». 28 3 СПЕЦІАЛЬНА ЧАСТИНА 35 3.1. Реалізація конфігурації. 35 4 БЕЗПЕКА ЖИТТЄДІЯЛЬНОСТІ, ОСНОВИ ОХОРОНИ ПРАЦІ 47 4.1. Загальна характеристика приміщення і робочого місця 48 4.2. Аналіз потенційно небезпечних і шкідливих виробничих факторів на робочому місці 49 ВИСНОВКИ 58 БІБЛІОГРАФІЯ 59

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Dissertations / Theses on the topic 'Flow lip'

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