This thesis is dedicated to the study of the interaction between a gas jet and a liquid film on a moving surface. This flow configuration corresponds to the gas-jet wiping technique, which is widely used in the coating industry to reduce and control the thickness of a liquid film dragged by a moving substrate. For that purpose, a turbulent slot jet impinges on the liquid surface, involving a runback flow and consequently a lower coating thickness downstream wiping. The different process parameters (nozzle pressure, nozzle to substrate standoff distance, slot width, substrate speed) allow controlling the final film thickness. This metering technique is very common in coating processes, such as the application of gelatin layers on photographic films. The first part of this thesis deals with the prediction of the mean jet wiping flow, i.e. the film thickness distribution in the wiping region. A lubrication model is developed for that purpose, which is simplified to a zero-dimensional model giving directly the final thickness In the second part, the prediction of splashing occurrence in jet wiping is addressed. The splashing phenomenon in jet wiping is featured by the ejection of droplets from the runback flow, and it constitutes a physical limit to the process. An experimental investigation is conducted on a water model facility, and based on a phenomenological description, a dimensionless correlation in terms of film Reynolds number and jet Weber number is derived for splashing occurrence. The latter is perfectly well validated with observations on industrial lines. The last part of this thesis is dedicated to the study of the unsteady phenomena occurring on the free surface of the liquid film downstream wiping. This phenomenon has never been understood nor characterized up to now. In the present research, undulation is investigated both theoretically and experimentally. Two model test facilities with dedicated measurement techniques have been designed and constructed. They allow performing parametric studies of the undulation characteristics (amplitude, wavelength, wave velocity), and analyzing the jet/film interaction.

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The purpose of this investigation is to analyze the flow pattern of cooling fluids in the 3D "twister-effect" mixing chamber and to approximate the free surface behaviors exiting the 2D spray nozzle. The cone angle and free surface height located at the end of the free surface are two significant factors to determine the spraying area on a heated plane. This process is a reasonable representation of many industrial cooling application. The whole system consists of 4 inlet tubes connected to the top of the mixing chamber, and the spray nozzle is located under the chamber. Four different refrigerants, like FC-72, FC-77, FC-87 and methanol were used for the turbulent flow simulations. According to different fluid properties, the cone angle, free surface, pressure drop and Reynolds number can be investigated at different flow rates. First, at a certain volumetric flow rates, the velocities in x, y, z directions were found on the positive x-axis (0 degree), y-axis (90 degrees), negative x-axis (180 degrees) and y-axis (270 degrees) at 8.0 x 10-4m below the top of chamber. After the transformations, the interpolated and averaged radial, circumferential and axial velocities were used in the 2D nozzle simulations. Finally, the cone angle, the radial locations of the free surface and the pressure drop were obtained in each scenario. As the results, higher volumetric flow rate produced higher free surface height and cone angle. Also, FC-87 created the highest free surface height and cone angle among all four working fluids in both volumetric flow rates. It means that FC-87 can produce the largest spraying area on the heated surface. Fluctuation, spinning and eddy circulation can be found in the velocity plot because of the turbulent flow syndromes. When comparing two different nozzle designs, it was found that the nozzle without mixing chamber gave a larger cone angle and free surface height. Alternatively, the design in this investigation produced a relatively narrow jet concentrated to the stagnation zone.

A conical nozzle with two separate inlets within its top plate is analyzed. One of the inlets is in the center of the top plate, which is free to rotate, whereas the other inlet is positioned away from the center. The fluid entering through the outer inlet slot causes the top plate of the nozzle to spin. Several fluids including FC-77, FC-72, FC-87, and Methanol running at different flow rates were investigated to observe the effect that their particular properties have on the geometry of the fluid's free surface exiting the nozzle. Another variation performed was the geometry of the nozzle. The outer inlet slot was positioned at various radial distances along the top plate. For this nozzle, the top plate remained stationary and swirling was introduced to the fluid at the inlets. It was observed that the faster flow rates caused an increase in the free surface height and cone angle. For the various radial locations of the outer inlet slot, it was noted that a position at approximately 75% of the nozzle radius produced the largest free surface height. The largest cone angle was produced when the outer inlet slot was positioned at the edge of the nozzle top plate. Another factor that increased the radial height and cone angle of the free surface was the working fluid used in the study. A larger Reynolds number produced a larger cone angle and larger free surface height (while a smaller Reynolds number produced a less significant cone angle and free surface height).

Title from PDF of title page. / Document formatted into pages; contains 230 pages. / Thesis (M.S.M.E.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: A conical nozzle with two separate inlets within its top plate is analyzed. One of the inlets is in the center of the top plate, which is free to rotate, whereas the other inlet is positioned away from the center. The fluid entering through the outer inlet slot causes the top plate of the nozzle to spin. Several fluids including FC-77, FC-72, FC-87, and Methanol running at different flow rates were investigated to observe the effect that their particular properties have on the geometry of the fluid's free surface exiting the nozzle. Another variation performed was the geometry of the nozzle. The outer inlet slot was positioned at various radial distances along the top plate. For this nozzle, the top plate remained stationary and swirling was introduced to the fluid at the inlets. It was observed that the faster flow rates caused an increase in the free surface height and cone angle. / ABSTRACT: For the various radial locations of the outer inlet slot, it was noted that a position at approximately 75% of the nozzle radius produced the largest free surface height. The largest cone angle was produced when the outer inlet slot was positioned at the edge of the nozzle top plate. Another factor that increased the radial height and cone angle of the free surface was the working fluid used in the study. A larger Reynolds number produced a larger cone angle and larger free surface height (while a smaller Reynolds number produced a less significant cone angle and free surface height). / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

Identification of disease-related alterations in molecular and cellular mechanisms may reveal useful biomarkers for human diseases including cancers. High-throughput omic technologies for identifying and quantifying multi-level biological molecules (e.g., proteins, glycans, and metabolites) have facilitated the advances in biological research in recent years. Liquid (or gas) chromatography coupled with mass spectrometry (LC/GC-MS) has become an essential tool in such large-scale omic studies. Appropriate LC/GC-MS data preprocessing pipelines are needed to detect true differences between biological groups. Challenges exist in several aspects of MS data analysis. Specifically for biomarker discovery, one fundamental challenge in quantitation of biomolecules is owing to the heterogeneous nature of human biospecimens. Although this issue has been a subject of discussion in cancer genomic studies, it has not yet been rigorously investigated in mass spectrometry based omic studies. Purification of mass spectometric data is highly desired prior to subsequent differential analysis. In this research dissertation, we majorly target at addressing the purification problem through probabilistic modeling. We propose an intensity-level purification model (IPM) to computationally purify LC/GC-MS based cancerous data in biomarker discovery studies. We further extend IPM to scan-level purification model (SPM) by considering information from extracted ion chromatogram (EIC, scan-level feature). Both IPM and SPM belong to the category of topic modeling approach, which aims to identify the underlying "topics" (sources) and their mixture proportions in composing the heterogeneous data. Additionally, denoise deconvolution model (DMM) is proposed to capture the noise signals in samples based on purified profiles. Variational expectation-maximization (VEM) and Markov chain Monte Carlo (MCMC) methods are used to draw inference on the latent variables and estimate the model parameters. Before we come to purification, other research topics in related to mass spectrometric data analysis for cancer biomarker discovery are also investigated in this dissertation. Chapter 3 discusses the developed methods in the differential analysis of LC/GC-MS based omic data, specifically for the preprocessing in data of LC-MS profiled glycans. Chapter 4 presents the assumptions and inference details of IPM, SPM, and DDM. A latent Dirichlet allocation (LDA) core is used to model the heterogeneous cancerous data as mixtures of topics consisting of sample-specific pure cancerous source and non-cancerous contaminants. We evaluated the capability of the proposed models in capturing mixture proportions of contaminants and cancer profiles on LC-MS based serum and tissue proteomic and GC-MS based tissue metabolomic datasets acquired from patients with hepatocellular carcinoma (HCC) and liver cirrhosis. Chapter 5 elaborates these applications in cancer biomarker discovery, where typical single omic and integrative analysis of multi-omic studies are included. / Ph. D. / This dissertation documents the methodology and outputs for computational deconvolution of heterogeneous omics data generated from biospecimens of interest. These omics data convey qualitative and quantitative information of biomolecules (e.g., glycans, proteins, metabolites, etc.) which are profiled by instruments named liquid (or gas) chromatography and mass spectrometer (LC/GC-MS). In the scenarios of biomarker discovery, we aim to find out the significant difference on intensities of biomolecules with respect to two specific phenotype groups so that the biomarkers can be used as clinical indicators for early stage diagnose. However, the purity of collected samples constitutes the fundamental challenge to the process of differential analysis. Instead of experimental methods that are costly and time-consuming, we treat the purification task as one of the topic modeling procedures, where we assume each observed biomolecular profile is a mixture of hidden pure source together with unwanted contaminants. The developed models output the estimated mixture proportion as well as the underlying “topics”. With different level’s purification applied, improved discrimination power of candidate biomarkers and more biologically meaningful pathways were discovered in LC/GC-MS based multi-omic studies for liver cancer. This research work originates from a broader scope of probabilistic generative modeling, where rational assumptions are made to characterize the generation process of the observations. Therefore, the developed models in this dissertation have great potential in applications other than heterogeneous data purification discussed in this dissertation. A good example is to uncover the relationship of human gut microbiome with the host’s phenotypes of interest (e.g., disease like type-II diabetes). Similar challenges exist in how to infer the underlying intestinal flora distribution and estimate their mixture proportions. This dissertation also covers topics of related data preprocessing and integration, but with a consistent goal in improving the performance of biomarker discovery. In summary, the research help address sample heterogeneity issue observed in LC/GC-MS based cancer biomarker discovery studies and shed light on computational deconvolution of the mixtures, which can be generalized to other domains of interest.

Esse trabalho apresenta um modelo termodinâmico de uma bomba multifásica do tipo duplo parafuso. Para uma dada condição de operação, o modelo calcula a potência consumida, as condições do fluido na descarga e o perfil de pressão ao longo da bomba. Ao invés de simular diretamente o escoamento dentro da bomba, simulou-se os processos que ocorrem dentro das suas câmaras. Para tanto, dividiu-se o processo de bombeamento multifásico em uma seqüência de processos simples, facilitando-se a construção do modelo no simulador de processos Hysys.Process v2.1. Os resultados de potência e temperatura de descarga obtidos com a simulação mostram uma boa concordância com valores experimentais, principalmente para FVG’s baixos. Para FVG’s elevados, o modelo passa a superestimar a potência consumida indicando que as fendas, nesses casos, já não se encontram totalmente preenchidas com líqüido. Dos resultados obtidos para o refluxo, conclui-se que, das equações sugeridas na literatura, aquelas para escoamento turbulento liso são mais adequadas para os números de Reynolds envolvidos. O perfil de pressão e a vazão de refluxo quando o escoamento é multifásico aproxima-se qualitativamente das medições experimentais. Estudou-se a influência de diversos parâmetros na eficiência exergética da bomba. Os resultados mostram que a otimização da eficiência depende das condições de operação da bomba: FVG, tipo de líqüido, diferença de pressão, entre outros. / The goal of this project was to develop a thermodynamic model of a twin-screw multiphase pump. With given operation conditions the model can determine the absorbed power, discharge conditions and the pressure profile along the screw. An alternative approach was suggested to overcome the complex flow problem and the processes inside the pump were simulated instead of direct simulation of the flow. For this purpose, the multiphase pumping process was divided in a sequence of simple processes so the model could be developed in an easier way. The power and temperature values calculated by the model are in good agreement with experimental data, mainly when the gas fraction is low. With higher gas fractions, the model overestimates the absorbed power indicating that screw gaps are not completely filled with liquid anymore. Concerning about the backflow rate, the results show that the equations for turbulent flow in smooth ducts fits better the Reynolds number range in the gaps. The pressure profile and backflow rate for multiphase flow agree qualitatively with experimental results. The influence of several parameters in the exergetic eficiency of the pump were analysed and results show that the efficiency optimization depends on pump operation conditions: gas fraction, liquid type, pressure difference and others.

Esse trabalho apresenta um modelo termodinâmico de uma bomba multifásica do tipo duplo parafuso. Para uma dada condição de operação, o modelo calcula a potência consumida, as condições do fluido na descarga e o perfil de pressão ao longo da bomba. Ao invés de simular diretamente o escoamento dentro da bomba, simulou-se os processos que ocorrem dentro das suas câmaras. Para tanto, dividiu-se o processo de bombeamento multifásico em uma seqüência de processos simples, facilitando-se a construção do modelo no simulador de processos Hysys.Process v2.1. Os resultados de potência e temperatura de descarga obtidos com a simulação mostram uma boa concordância com valores experimentais, principalmente para FVG’s baixos. Para FVG’s elevados, o modelo passa a superestimar a potência consumida indicando que as fendas, nesses casos, já não se encontram totalmente preenchidas com líqüido. Dos resultados obtidos para o refluxo, conclui-se que, das equações sugeridas na literatura, aquelas para escoamento turbulento liso são mais adequadas para os números de Reynolds envolvidos. O perfil de pressão e a vazão de refluxo quando o escoamento é multifásico aproxima-se qualitativamente das medições experimentais. Estudou-se a influência de diversos parâmetros na eficiência exergética da bomba. Os resultados mostram que a otimização da eficiência depende das condições de operação da bomba: FVG, tipo de líqüido, diferença de pressão, entre outros. / The goal of this project was to develop a thermodynamic model of a twin-screw multiphase pump. With given operation conditions the model can determine the absorbed power, discharge conditions and the pressure profile along the screw. An alternative approach was suggested to overcome the complex flow problem and the processes inside the pump were simulated instead of direct simulation of the flow. For this purpose, the multiphase pumping process was divided in a sequence of simple processes so the model could be developed in an easier way. The power and temperature values calculated by the model are in good agreement with experimental data, mainly when the gas fraction is low. With higher gas fractions, the model overestimates the absorbed power indicating that screw gaps are not completely filled with liquid anymore. Concerning about the backflow rate, the results show that the equations for turbulent flow in smooth ducts fits better the Reynolds number range in the gaps. The pressure profile and backflow rate for multiphase flow agree qualitatively with experimental results. The influence of several parameters in the exergetic eficiency of the pump were analysed and results show that the efficiency optimization depends on pump operation conditions: gas fraction, liquid type, pressure difference and others.

El presente trabajo realizado se centra en la investigación del impacto tributario que se puede generar por las mermas de GLP en las estaciones de servicio del Cercado de Lima en el periodo 2017. Las mermas son la reducción del volumen o la cantidad, el GLP por ser de naturaleza gaseosa tiende a evaporarse, por lo que la compañía para efectos de sustentar estas pérdidas debe elaborar un informe técnico elaborado por un tercero independiente con el fin de obtener un beneficio para efecto de disminuir la base tributaria para el cálculo de la renta. En el flujo de comercialización del GLP en las estaciones de servicio, el gas es transportado desde el tanque estacionario hasta la máquina surtidora del combustible, en esta línea de secuencia se puede perder gas que pasaría a ser merma por la actividad del negocio. En el desarrollo de este trabajo conoceremos un caso en específico de una compañía que no pudo sustentar las mermas generadas en su ejercicio, ya que la Administración Tributaria consideró inadecuado la solicitud de deducir las mermas por no resultar normal en el negocio. Es aquí donde se genera una controversia acerca del presumible vacío que queda en la norma. Al captar este tema de nuestro interés pasaremos a desarrollar la investigación sobre la actualidad de las estaciones de servicio y qué procedimientos aplican estas compañías respecto al tratamiento sobre las mermas de GLP. / The present work is focused on the investigation of the tax impact that can be generated by the petroleum liquid gas losses in the service stations of the Cercado de Lima in the period 2017. The losses are the reduction of the volume or quantity, the petroleum liquid gas being A gaseous nature tends to evaporate, so that the company for the purpose of sustaining these losses must prepare a technical report prepared by an independent third party in order to obtain a benefit in order to reduce the tax base for the calculation of income. In the petroleum liquid gas marketing flow at the service stations, the gas is transported from the stationary tank to the fuel dispensing machine, in this sequence line gas can be lost that would become depleted by the business activity. In the development of this work we will know a specific case of a company that could not sustain the losses generated in its exercise, since the Tax Administration considered inappropriate the request to deduct the losses for not being normal in the business. It is here that a controversy is generated about the presumable void that remains in the norm. By capturing this topic of our interest, we will develop research on the topicality of service stations and what procedures these companies apply regarding the treatment of the petroleum liquid gas waste. / Tesis

Les écoulements en milieux poreux sont omniprésents tant dans la nature que dans l'industrie. Les travaux menés dans cette thèse ont pour objectif d’étudier ces écoulements en présence de liquide et de gaz. Cela correspond aux situations d'imbibition (ou invasion capillaire), de drainage (ou déplacement d'un fluide mouillant par la mise en pression d'un fluide non mouillant), et d'évaporation (ou de séchage). L'étude se base sur l'utilisation de systèmes modèles artificiels. Une première partie de ce travail se concentre sur les écoulements liquide-gaz dans les milieux dont la taille des pores est inférieure à 100 nm. Ces milieux sont dits nanoporeux. A cette échelle, différents phénomènes sont susceptibles de modifier les écoulements liquide-gaz par rapport à ce qui est observé à l’échelle micrométrique : accrochage de la ligne de contact, pression fortement négative en phase liquide ou cavitation par exemple. Des expériences sont donc nécessaires pour mieux caractériser ces écoulements. En parallèle, les récents progrès en nanofabrication permettent d’obtenir des systèmes dont la profondeur peut descendre jusqu’à quelques nanomètres. Cette approche, désormais classique à plus grande échelle, nous fournit un outil innovant pour étudier les écoulements dans des milieux nanoporeux modèles, en deux dimensions. Un atout évident de ce type de modèles est qu'ils permettent une visualisation directe des deux phases, liquide et gaz. Des dispositifs nanofluidiques en silicium-verre et à profondeur constante ont été réalisés dans la gamme 20-500 nm. Un nouveau procédé de nanofabrication basé sur une lithographie laser à niveau de gris a été développé afin d’obtenir des dispositifs à profondeurs variables en une seule étape. Les expériences d'imbibition et un modèle théorique ont mis en avant que la pressurisation du gaz accélère son transport dans le liquide. Ensuite, des expériences de drainage ont été réalisées dans des dispositifs nanofluidiques avec des pressions de l’ordre de 20 bars. Des simulations sur réseau de pores utilisant l’algorithme de percolation d'invasion ont montré que les motifs d'invasion expérimentaux correspondaient à ce qui était attendu à l’échelle micrométrique pour des écoulements à faible nombre capillaire. Enfin, l'évaporation en nanocanaux a révélé des cinétiques intéressantes d'apparition et de croissance de bulles dans le liquide. Une ouverture est faite sur l'intérêt de poursuivre ces études dans des systèmes déformables. La deuxième partie de cette thèse s'est focalisée sur la cristallisation du chlorure de sodium à l'échelle d’un pore micrométrique. Dans le cas particulier du séchage d'une solution de sel, l'évaporation amène à la cristallisation des espèces dissoutes. Ce phénomène est largement impliqué dans la problématique de la conservation des oeuvres d'arts ou de la détérioration précoce des édifices. Les mécanismes qui conduisent à la génération de contraintes par un cristal sur une paroi, appelée pression de cristallisation, ne sont pas encore admis tant à l’échelle macro que microscopique. Des déformations induites par la cristallisation du sel ont été observées dans des dispositifs microfluidiques verre-polymère (PDMS). La vitesse de croissance d’un cristal a été mesurée à haute cadence d'acquisition, aboutissant à une nouvelle valeur de la constante de cinétique de réaction, supérieure d'un à deux ordres de grandeur aux données de la littérature. Un modèle numérique prédit l'évolution du champ de concentration en sel dissous lors de la croissance du cristal. Complété par une analyse théorique qui a mis en avant un nombre de Damkhöler prenant en compte les propriétés de transport et la taille du pore, il a permis de construire un diagramme de phase qui traduit les conditions favorables à la génération de contraintes par un cristal sur une paroi. Enfin, un mécanisme de génération de contraintes négatives entraînant la fermeture du pore a été observé. / Flows in porous media are ubiquitous in nature and industry. The aim of this thesis work is to study these flows in presence of liquid and gas, relying on the use of artificial model systems. They correspond to imbibition (or capillary invasion), drainage (or the displacement of a wetting fluid by a non-wetting fluid), and evaporation (or drying). A first part of this work focuses on the liquid-gas flows in porous media whose pore size is lower than 100 nm. They are called nanoporous media. At this scale, several phenomenamight modify the liquid-gas flows in comparison with what is known at the micrometer scale: e.g. contact line pinning, high negative pressure in liquid or cavitation. Thus, experiments are needed to better characterize these flows. In parallel, recent progresses in nanofabrication allow fabricating devices whose depth drop down to few nanometers. This approach provide an innovative tool to study the flows in nanoporous model systems in two dimensions, as it has been already performed at larger scale. A clear advantage to this system is that it allows direct observation of different phases. Silicon-glass nanofluidic devices were fabricated with constant depth in the 20-500 nm range. A new fabrication process was developed to obtain nanochannel with non-uniform depth in one step. It is based on grayscale laser lithography. Imbibition experiments and a numerical model showed that the gas pressurization increased the gas transfer throw the liquid. Drainage experiments were performed in devices with pressure as high as 20 bars. Pore networks modeling with invasion percolation algorithmshowed that the experimental invasion patterns correspond to those expected at micrometer scale for low Capillary number. Evaporation in nanochannels revealed interesting kinetics of bubbles appearance and growth. A prospective study is shown at the end to argue the importance of pursuing these studies in deformable media. The second part of this work concentrates on the sodium chloride crystallization at the scale of a micrometer pore. In the specific case of the drying of a salt solution, evaporation leads to the crystallization of the dissolved species. This phenomenon is involved in the issue of art conservation or building salt weathering. The mechanisms which lead to a stress on wall induced by a crystal are not generally admitted both at macro and microscale. Deformations induced by crystal growth were observed in glass-polymer (PDMS) microfluidic devices. The crystal growth kinetics was measured at high acquisition rate and allowed giving a new value of the parameter of kinetics of crystal growth by reaction, one to two orders of magnitude higher than the ones used in literature. A numerical model was developed to predict the evolution of dissolved salt concentration during crystal growth. It allowed designing a phase diagram which gives the condition to favors the stress generation by a crystal on a wall. A theoretical analysis defined a Damkhöler number, taking into account transport properties and pore size. At last, a stress generation mechanism was observed, leading to the pore closure.