Дисертації з теми "Evaporation processes"
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Lundberg, Angela. "Interception evaporation : processes and measurement techniques." Doctoral thesis, Luleå tekniska universitet, Geovetenskap och miljöteknik, 1996. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25799.
Повний текст джерелаGodkänd; 1996; 20070428 (ysko)
Vetrano, Maria. "Rainbow thermometry development and application to evaporation and diffusion processes." Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/216588.
Повний текст джерелаIn this thesis the Airy theory, which is used as theoretical model for the Standard Rainbow Thermometry, has been improved to minimize the discrepancies it was presenting respect to more complex and complete theories and it has been generalized to spherical particles presenting a spherically symmetric refractive index gradient. This generalized model has been used to evaluate the size and temperature of a n-octane burning droplet in standard atmosphere with good results. The generalization of the Standard Rainbow Thermometry to multiple particles, Global Rainbow Thermometry, is presented both theoretically and experimentally and the role of the particle asphericity in the light scattered intensity is evaluated.
Two experimental application of the Global Rainbow Thermometry are reported. The first one concerns the measurement of size and refractive index of silicon oil droplets suspended in an aqueous bulk. This experiment allows the Global Rainbow Thermometry validation through the comparison with measurements simultaneously obtained with well known experimental techniques as Back-Light scattering and thermocouple measurement with satisfactory results.
The second experiment concerns Global Rainbow Thermometry measurement performed on an evaporating flat-fan water spray. The results obtained, both for temperature and for size, are in satisfactory agreement with predictions already done by other authors and with numerical simulations performed by the engineering code CASIMIRE.
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
Shukri, Ziad A. (Ziad Aziz). "Evaporation and sputtering processes for Se-CdO photovoltaic cell structures." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59607.
Повний текст джерелаSouche, Mireille, and Didier Long. "Ultra fast processes for solvent evaporation in thin polymer films below Tg." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-195014.
Повний текст джерелаSouche, Mireille, and Didier Long. "Ultra fast processes for solvent evaporation in thin polymer films below Tg." Diffusion fundamentals 3 (2005) 36, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14326.
Повний текст джерелаSchmidt, Olaf. "Heat transfer and evaporation in spray cooling of hot gas flows, including the effect of nozzle design." Thesis, Middlesex University, 2001. http://eprints.mdx.ac.uk/13382/.
Повний текст джерелаBarella, Ortiz Anais. "Analysis and modelling of soil moisture and evaporation processes, implications for climate change." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066115/document.
Повний текст джерелаThis thesis deals with the study of evaporation and soil moisture, t wo main parameters of the hydrological cycle, and thus the climate system. First, potential evaporation (ET P ) is analysed. It is an important input to hydrological and agronomic models, key to describe the interactions between the surface e and the atmosphere, and the basis of most of the estimations of actual evapora tion. Physically-based and empirical methods to estimate ET P are evaluated, at a global scale, under current climate conditions and in a changing climate. The former methods correspond to those implemented in land surface models (LSM) and the Food and Agriculture Organization (F AO) reference evapotranspiration equation. The assumptions made in FAO's method underest imate ET P if compared to LSM methods. They also result in a lower sensitive ty of ET P to climate change. In addition, empirical equations are not able to reproduce the impact of climate change on ET P if compared to that from LSM methods. Soil moisture is the second aim of this thesis. It is treated t hrough the analysis of brightness temperatures (TB). These are a measure of the radiation emitted by the surface , and thus an optimum parameter to use in remote sensing techniques for soi l moisture retrieval. Measured TB from the Soil Moisture and Ocean Salinity (SMOS) mission are compared, over the Iberian Peninsula, to two sets of TB modelled estimates from two LSM. There is a good agreement in the temporal evolution between them. However, discrepancy es are found regarding the spatial structures, which become more evident during fall and winter and are mainly explained by differences in the annual cycle of measured and modelled TB
Hassan, Aseel Kadhim. "Studies in electronic conduction processes in organic semiconducting thin films of copper phthalocyanine prepared by evaporation." Thesis, Keele University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306847.
Повний текст джерелаPersson, Tony. "Evaporation and Heat-flux Aggregation in Heterogeneous Boreal Landscapes." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4326.
Повний текст джерелаThe boreal forests represent 8 % of all forested areas on the earth and have a significant role in the control of greenhouse gases and an impact on global climate change. The main objective of this thesis is to increase the understanding of how evaporation and heat-flux processes in the boreal forest zone are affecting the regional and global climate.
A meteorological mesoscale model with an advanced land-surface parameterization has been utilized to study aggregation of fluxes of water vapour and heat. The model has been compared against four other methods for flux estimation in a southern boreal landscape. The results show that the mesoscale model is successfully reproducing 24-hour averages of fractionally weighted mast measurements of sensible and latent heat flux.
The model was also evaluated against in-situ observations of surface fluxes and other meteorological variables. The results reveal that a correct initialization of soil moisture is crucial to simulate a realistic partitioning of the sensible and latent heat fluxes. Significant differences in surface fluxes and friction velocities between two apparently similar forest sites indicate the need for careful assessment of areal representativity when comparing mesoscale model results with in-situ observations.
A parameterization for the absorption of solar radiation of high-latitude sparse forests was implemented and tested in the model that significantly improved the simulation of high wintertime midday sensible heat fluxes. A scheme for heat storage in vegetation was also implemented which improved the results, but the scheme needs further evaluation for high latitude forests.
Two commonly used strategies for the description of land-surface heterogeneity, the effective parameter approach and the mosaic approach, were tested in the mesoscale model against airborne observations of sensible and latent heat fluxes. The results show that the mosaic approach produces better results especially when small lakes are present in model grid-squares.
Norra halvklotets barrskogsbälte representerar 8 % av all skogsbeklädd mark på jorden och har stor betydelse för kontrollen av växthusgaser och påverkan på globala klimatförändringar. Syftet med denna avhandling är att öka förståelsen av hur avdunstning och värmeflöden i den boreala skogszonen påverkar klimatet regionalt och globalt.
En meteorologisk mesoskalemodell med en avancerad landyteparameterisering har använts för att studera aggregering av avdunstning och värmeflöden. Modellen jämfördes med fyra andra metoder för uppskattning av värmeflöden i den boreala skogszonens södra delar. Resultaten visade att mesoskalemodellen reproducerar 24-timmarsmedelvärden av sensibelt och latent värmeflöde från areellt viktade mastmätningar med bra resultat.
Modellen utvärderades även mot markbaserade mätningar av sensibelt och latent värme och andra meteorologiska variabler. Resultaten visar att en korrekt initialisering av markvatteninnehållet är avgörande för att simulera en realistisk uppdelning av de sensibla och latenta värmeflödena. Markanta skillnader i markyteflöden och friktionshastigheter mellan två liknande skogsmätstationer påvisar nödvändigheten av en noggrann bedömning av den areella representativiteten när man jämför resultat från mesoskalemodellen med markbaserade mätningar.
En parameterisering för absorption av solstrålning i glesa skogsbestånd på höga breddgrader infördes och testades i modellen vilket markant förbättrade simuleringen av de höga sensibla värmeflöden som observerats vid middagstid på vintern. Ett uttryck för att beskriva värmelagring i vegetationen infördes också vilket förbättrade resultaten, men uttrycket behöver vidare utvärdering för skogsbestånd på höga breddgrader.
Två ofta använda strategier för att beskriva markytans heterogenitet, effektiva parametermetoden och mosaikmetoden, testades i mesoskalemodellen mot flygburna observationer av sensibla och latenta värmeflöden. Resultaten visar att mosaikmetoden ger bättre resultat särskilt när mindre sjöar förekommer i modellrutorna.
Höfler, Matthias [Verfasser], Reinhold [Akademischer Betreuer] Kneer, and Manfred Christian [Akademischer Betreuer] Wirsum. "Theoretical evaluation of falling film evaporation for organic rankine cycle processes / Matthias Höfler ; Reinhold Kneer, Manfred Christian Wirsum." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1211960048/34.
Повний текст джерелаXie, Jianfei. "Development of a new kinetic model for the analysis of heating and evaporation processes in complex hydrocarbon fuel droplets." Thesis, University of Brighton, 2013. https://research.brighton.ac.uk/en/studentTheses/866b0ab3-7dcc-44e4-8334-57d56b73cce3.
Повний текст джерелаMosthaf, Klaus [Verfasser], and Rainer [Akademischer Betreuer] Helmig. "Modeling and analysis of coupled porous-medium and free flow with application to evaporation processes / Klaus Mosthaf. Betreuer: Rainer Helmig." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2014. http://d-nb.info/1049438876/34.
Повний текст джерелаKumar, Abhijeet Verfasser], Tatiana [Akademischer Betreuer] [Gambaryan-Roisman, Peter [Akademischer Betreuer] Stephan, and Klitzing Regina [Akademischer Betreuer] von. "Wetting, evaporation and deposition processes in interaction of complex liquid formulations with porous substrates / Abhijeet Kumar ; Tatiana Gambaryan-Roisman, Peter Stephan, Regina von Klitzing." Darmstadt : Universitäts- und Landesbibliothek, 2020. http://nbn-resolving.de/urn:nbn:de:tuda-tuprints-142114.
Повний текст джерелаKumar, Abhijeet [Verfasser], Tatiana [Akademischer Betreuer] Gambaryan-Roisman, Peter [Akademischer Betreuer] Stephan, and Klitzing Regina [Akademischer Betreuer] von. "Wetting, evaporation and deposition processes in interaction of complex liquid formulations with porous substrates / Abhijeet Kumar ; Tatiana Gambaryan-Roisman, Peter Stephan, Regina von Klitzing." Darmstadt : Universitäts- und Landesbibliothek, 2020. http://d-nb.info/1222163195/34.
Повний текст джерелаWallis, Kirsty. "Design of experiment studies for the fabrication processes involved in the micro-texturing of surfaces for fluid control." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8456.
Повний текст джерелаVera-Tudela, Fajardo Walter Martin. "An experimental study of the effects of fuel properties on diesel spray processes using blends of single-component fuels." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/58865.
Повний текст джерела[ES] Estos últimos años, la tendencia en motores diesel ha sido la de emplear distintos tipos de combustibles para identificar su influencia y comportamiento sobre las emisiones y rendimiento. Dentro de la amplia variedad de combustibles empleados están los llamados combustibles de referencia (PRFs ingl. Primary Reference Fuels), los cuales representan el comportamiento del diesel y la gasolina en lo que respecta a propiedades de encendido, ya que se encuentran en ambos extremos de la escala del número de octano y también poseen números de cetano muy distintos. Una de las desventajas de utilizar gasolina pura o mezclas de diesel-gasolina en motores diesel es el tiempo que toma la mezcla en encender y quemar completamente el combustible. Esto generalmente requiere trabajar con cargas parciales o cargas premezcladas. Para poder aislar los efectos del combustibles sobre los procesos de un chorro y que sea capaz estudiar los parámetros característicos de tiempo de retraso de encendido, longitud de despegue de llama, penetración de líquido y vapor, entre otros, se han realizado distintos experimentos bajo variaciones paramétricas de condiciones de motor diesel. Los ensayos han sido realizados bajo condiciones inertes y reactivas en un motor óptico de dos tiempos y una instalación de alta presión y alta temperatura de flujo continuo a presión constante (CPF ingl. Constant-Pressure Flow) empleando toberas mono-orificio, con aplicación de diversas técnicas ópticas. Para estudiar la influencia de las propiedades de los combustibles se utilizaron distintos mono-componentes, así como mezclas binarias y un sustituto de diesel conformado por seis componentes, el cual fuel comparado con diesel convencional. Adicionalmente, los resultados han sido contrastados con un modelo unidimensional para ayudar a explicar los valores y tendencias encontrados. Los resultados presentaron una fuerte dependencia de las propiedades de los combustibles en los ensayos realizados bajo condiciones inertes y reactivas. La diferencia entre las propiedades físicas del n-decano y n-hexadecano mostraron una reducción casi lineal sobre la longitud líquida estabilizada hasta aproximadamente un 60% bajo ciertas condiciones. Adicionalmente, debido a la composición del combustible de sustitución, el n-hexadecano puro demostró tener características de evaporación prácticamente idénticas, probándose a sí mismo como un buen candidato para ser un sustituto mono-componente del diesel convencional. De una manera similar, las propiedades químicas de los PRFs n-heptano e iso-octano también probaron tener influencia sobre el desarrollo del chorro y radiación emitida. Se obtuvieron valores de tiempo de retraso con diferencias de hasta un orden de magnitud entre ambos extremos del rango de las mezclas, así como longitudes de despegue de llama hasta tres veces más largas. La radiación emitida por la incandescencia del hollín presentó las variaciones más altas, ya que algunas condiciones mostraron reducciones de hasta cuatro órdenes de magnitud dentro del rango de mezclas. Es más, algunos casos no presentaron radiación correspondiente al hollín, e incrementar la sensibilidad de la cámara solo ocasionó que la quimioluminiscencia del radical OH* sea detectada. Por otro lado, la longitud estabilizada de llama calculada mediante la radiación del hollín no presentó mucha variación respecto a las propiedades del combustible o la temperatura del aire. De hecho, la única diferencia apreciable fue causada por los cambios en la composición del oxígeno del aire ambiente. En conclusión, las propiedades de los combustibles demostraron tener un efecto significativo en los procesos de un chorro diesel. Los combustibles más ligeros favorecieron la evaporación del chorro en un rango de condiciones, mientras que combustibles con números de octano más bajos encendieron más pronto y cerca de la tobera pero con mayor luminosidad del hollín medida.
[CAT] En aquests últims anys, la tendència en motors Diesel ha estat la d'emprar diferents tipus de combustibles per a identificar la seva influència i comportament sobre les emissions i rendiment. Dintre de l'àmplia varietat de combustibles emprats estan els anomenats combustibles de referència (PRFs angl. Primary Reference Fuels), els quals representen el comportament del dièsel i la gasolina pel que fa a propietats d'encesa, ja que es troben en ambdós extrems de l'escala del nombre d'octà i també posseeixen nombres de cetà molt diferents. Un dels desavantatges d'utilitzar benzina pura o barreges de Diesel-benzina en motors Diesel és el temps que pren la barreja a encendre i cremar completament el combustible. Això generalment requereix treballar amb càrregues parcials o càrregues premesclades. Per a poder aïllar els efectes del combustibles sobre els processos d'un doll i que sigui capaç estudiar els paràmetres característics de de temps de retard d'encesa, longitud d'enlairament de flama, penetració de líquid i vapor, entre altres, s'han estudiat diferents experiments sota variacions paramètriques de condicions de motor Diesel. Els assajos han estat realitzats sota condicions inertes i reactives en un motor de dos temps i una instal·lació d'alta pressió i alta temperatura de flux continu a pressió constant (CPF angl. Constant-Pressure Flow) emprant toberes mono-orifici, amb aplicació de diverses tècniques òptiques. Per a estudiar la influència de les propietats dels combustibles, van ser utilitzats distints mono-components, així com barreges binàries i un substitut de Diesel conformat per sis components, el qual fuel comparat amb Diesel convencional. Addicionalment, els resultats han estat contrastats amb un model unidimensional per a ajudar a explicar els valors i tendències trobats. Els resultats van presentar una forta dependència de les propietats dels combustibles en els assajos realitzats sota condicions inertes i reactives. La diferència entre les propietats físiques del n-decà i n-hexadecà van mostrar una reducció gairebé lineal sobre la longitud líquida estabilitzada fins a aproximadament un 60% sota certes condicions. Addicionalment, degut a la composició del combustible de substitució, el n-hexadecà pur va demostrar ser tindre característiques d'evaporació pràcticament idèntiques a aquell, demostrant ser un bon candidat per a ser un substitut mono-component del dièsel convencional. D'una manera similar, les propietats químiques dels PRFs n-heptà i iso-octà també provaren tindre influència sobre el desenvolupament del doll i la radiació emesa. Es van obtenir valors de temps de retard amb diferències de fins a un ordre de magnitud entre ambdós extrems del rang de les barreges, així com longituds d'enlairament de flama fins a tres vegades més llargues. La radiació emesa per la incandescència del sutge va presentar les variacions més grans, ja que algunes condicions van mostrar reduccions de fins a quatre ordres de magnitud dintre del rang de barreges. Encara més, alguns casos no van presentar radiació corresponent al sutge, i incrementar la sensibilitat de la càmera solament va ocasionar que la quimioluminiscència del radical OH* sigui detectada. D'altra banda, la longitud estabilitzada de flama calculada mitjançant la radiació del sutge no va presentar molta variació respecte a les propietats del combustible o la temperatura del aire. De fet, la única diferència apreciable va ser causada pels canvis en la composició del oxigen de l'aire ambient. En conclusió, les propietats dels combustibles van demostrar tenir un efecte significatiu en els processos d'un doll dièsel. Els combustibles més lleugers van afavorir l'evaporació del doll en un rang de condicions, mentres que els combustibles amb nombre d'octà més baixos van prendre més aviat i prop de la tovera però amb més lluminositat del sutge mesurat.
Vera-Tudela Fajardo, WM. (2015). An experimental study of the effects of fuel properties on diesel spray processes using blends of single-component fuels [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/58865
TESIS
Öman, Cecilia. "Emissions of organic compounds from landfills /." Stockholm : Tekniska högsk, 1998. http://www.lib.kth.se/abs98/oman0604.pdf.
Повний текст джерелаBaumann, Gunther [Verfasser], Wilhelm [Akademischer Betreuer] Dominik, Jan [Akademischer Betreuer] Henninges, Frank [Akademischer Betreuer] Börner, and Michael [Akademischer Betreuer] Kühn. "Determination of displacement and evaporation/precipitation processes via Pulsed Neutron-Gamma (PNG) monitoring for CO2 storage operations / Gunther Baumann. Gutachter: Wilhelm Dominik ; Frank Börner ; Michael Kühn ; Jan Henninges. Betreuer: Wilhelm Dominik ; Jan Henninges." Berlin : Technische Universität Berlin, 2013. http://d-nb.info/1065665113/34.
Повний текст джерелаDanovič, Jakub. "Eliminace degradačních procesů kovových tenkých vrstev." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-221002.
Повний текст джерелаCavallius, Matilda, and Oskar Rehnstedt. "Befuktning : Installationer, processer och hälsofördelar." Thesis, KTH, Byggteknik och design, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215298.
Повний текст джерелаThere are clear health benefits of having a relative humidity between 40–60% indoors. Despite this, there are currently no directives on what level the relative humidity should be indoors. Today dehumidification is a common matter but this report is about humidification, from a health perspective.In this study, it has been investigated whether humidification could be used to a greater extent, to the benefit of humans’ health.This report describes various humidification methods and their thermophysical processes - adiabatic and isothermal. It is also explained what happens to the energy in the air and water vapor at different temperatures and how the relative humidity affects our health at different levels.The result shows that there is a need for humidification and that there are several technical solutions available today. However, the demand is low and the industry is not very positive to the idea of humidification in ventilation systems.
Berthias, Francis. "Thermalisation dans une nanogoutte d’eau." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1164/document.
Повний текст джерелаThe evaporation of a water molecule resulting in the rupture of one or more hydrogen bonds. These hydrogen bonds are responsible for many remarkable properties of water. At the macroscopic scale, water is well known for its ability to thermalize a system, while at the microscopic level, a high-speed transfer of vibrational energy through hydrogen bonding was observed. What scale of nanogoutte when a limited number of molecules come into play? In the experiment carried out with the device DIAM IPN Lyon, the relaxation of a nanogoutte of protonated water is observed after electronic excitation of one of its molecules. The implementation of a velocity vector imaging method associated with the technical COINTOF (Correlated Ion and Neutral Time-Of-Flight) allowed the measurement of the velocity distribution of molecules of evaporated protonated water clusters, mass and energy preselected. The shape of the measured velocity distributions shows that even for some nanodroplets composed of few water molecules, the energy is redistributed in the drop before evaporation. For nanodroplets containing less than ten water molecules, the measured velocity distributions are closed to those expected for macroscopic droplets. The statistical redistribution of energy appears as a dominant relaxation process. However, the measurement of the velocity distribution also highlights a distinct contribution at high velocity corresponding to the ejection of a molecule before complete redistribution of energy. The measured velocity distributions for heavy water nanodroplets deuterated show a proportion of non-ergodic most important events that for normal water. The measurements carried out with different target atoms show that the proportion of non-ergodic events decreases with decreasing the energy deposited in the nanogoutte
Arora, Sachin. "Modeling and control of emulsion polymerization processes with evaporative cooling." Aachen Shaker, 2007. http://d-nb.info/988687267/04.
Повний текст джерелаArora, Sachin. "Modeling and control of emulsion polymerization processes with evaporative cooling /." Aachen : Shaker, 2008. http://d-nb.info/988687267/04.
Повний текст джерелаArora, Sachin [Verfasser]. "Modeling and Control of Emulsion Polymerization Processes with Evaporative Cooling / Sachin Arora." Aachen : Shaker, 2008. http://d-nb.info/1162791705/34.
Повний текст джерелаCabrera, Jamoule Juan. "Etude des processus de fusion-fission et de fusion-évaporation dans l'interaction 20 Ne + 159 Tb entre 8 et 16 MeV/nucléon." Université catholique de Louvain, 2002. http://edoc.bib.ucl.ac.be:81/ETD-db/collection/available/BelnUcetd-06022006-191457/.
Повний текст джерелаKam, Kiew M. "Simulation and implementation of nonlinear control systems for mineral processes." Thesis, Curtin University, 2000. http://hdl.handle.net/20.500.11937/2383.
Повний текст джерелаZago, Gustavo Pereira. "Estudo da co-cristalização em sistema ternário NaCI-CaSO4-H2O para dessalinização de água." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-15012018-132007/.
Повний текст джерелаThe accelerated growth of the world population and the consequent increase in the production of consumer goods, has driven to a crisis in the availability of natural resources, especially water. Due to the scarcity of water resources, industrial and domestic wastewater treatment processes that aim the Zero Liquid Discharge (ZLD) have been increasingly studied. Nowadays, several processes have been used for this purpose. However, in all of them, there is still the generation of a brine composed of a concentrated salt solution, concomitantly with the recovered water, whose composition is normally constituted by different types of inorganic salts. One way to achieve the ZLD is through the implementation of an additional separation process, for which the evaporative crystallization is considered technically viable for this purpose. The use of this process is limited to the control of the morphological characteristics of the particles obtained, since this influences directly the separation effectiveness of the downstream processes to crystallization (filtration, centrifugation). Besides, industrial effluents are complex solutions and its crystallization involves the presence of more than one salt in solution (cocrystallization). This process is still not well investigated on scientific literature, thus, the determination of process conditions aiming to control the characteristics of these particles is not trivial. In this work, the effect of the evaporation rate and the presence of seeds on the morphology, composition, size and habit of sodium chloride and calcium sulfate particles obtained by batch evaporative co-crystallization were studied. The results were used to determine the operating parameters for the cocrystallization in order to obtain particles with high average size and narrow dispersion of sizes. High evaporation rates favored the obtaining of agglomerated particles. The presence of calcium sulfate in solution resulted in larger particles, less polydisperse and with less degree of agglomeration. Such result was considered positive, since, these characteristics are desirable for the separation of the crystals from the solution. Seeds of hemihydrate inhibited the agglomeration of the NaCl crystals. The increase in seed load of hemihydrate culminated in obtaining less agglomerated particles, but there was an increase in particle size distributions. In the experiments in which seeds of both salts were used, the same effect in the agglomeration was observed. In all experiments with seeds of hemihydrate, agglomeration of this salt with NaCl was observed, which was intensified with increasing evaporation rate and increasing seed amount. It was identified the possibility of recovery of both salts and, for certain conditions, obtaining more than 90% of NaCl with up to 99.50% purity.
Kam, Kiew M. "Simulation and implementation of nonlinear control systems for mineral processes." Curtin University of Technology, School of Chemical Engineering, 2000. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=10063.
Повний текст джерелаnonlinear control structures that are simple and computationally efficient have been proposed for enhancing the performance of geometric nonlinear controllers in the presence of plant/model mismatch and/or external disturbances. The robust nonlinear control structures are based on model error compensation methods. Robustness properties of the proposed robust nonlinear control structures on the evaporator system were investigated through computer simulations and the results indicated improved performance over the implemented geometric nonlinear controller in terms of model uncertainty and disturbance reductions.A software package was developed in MAPLE computing environment for the analysis of nonlinear processes and the design of geometric nonlinear controllers. This developed symbolic package is useful for obtaining fast and exact solutions for the analysis and design of nonlinear control systems. Procedures were also developed to simulate the geometric nonlinear control systems. It was found that MAPLE, while it is superior for the analyses and designs, is not viable for simulations of nonlinear control systems. This was due to limitation of MAPLE on the physical, or virtual, memory management. The use of both symbolic and numeric computation for solutions of nonlinear control system analysis, design and simulation is recommended.To sum up, geometric nonlinear controllers have been designed for an industrial multiple stage evaporator system and their simplicity, practicality, feasibility and superiority for industrial control practices have been demonstrated either through computer simulations or real-time implementation. It is hoped that the insights provided in this thesis will encourage more industry-based projects in nonlinear control, and thereby assist in closing the widening gap between academic nonlinear control theory and industrial control ++
practice.Keywords: geometric nonlinear control, input-output linearization, multiple stage evaporator, robust geometric nonlinear control, control performance enhancement.
To, Lap C. "Nonlinear control techniques in alumina refineries." Thesis, Curtin University, 1996. http://hdl.handle.net/20.500.11937/130.
Повний текст джерелаRisse, Benedikt. "Continuous crystallization of ultra-fine energetic particles by the Flash-Evaporation Process." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0144/document.
Повний текст джерелаHigh explosives, such as TNT or RDX, may be accidentally initiated under the influence of a strong mechanical impulse, great heat or an electrostatic discharge. Smallest impurities, open pores, entrapped gases or other inhomogeneities within the explosive matrix may convert the delivered energy into heat, causing the formation of a so called hot-spot. A hot-spot size of a few micrometers can already be sufficient to initiate a deflagration or even a detonation of the explosive. By decreasing the particle size of the explosive, the formation of hot-spots is inhibited, resulting in a less sensitive material. In this work, a continuous operating flash-crystallization process was developed, being able to produce energetic submicron particles in a multigram scale. The process bases on a spray drying process where superheated solutions are continuously atomized. A parametric study was performed on this process in order to decrease the particle size and obtaining a narrower particle size distribution. By means of this flash-crystallization process, highly homogeneous energetic composites were prepared in a large scale. The quality and amount of the energetic composite are unique. The versatility of the flash-crystallization process allows the preparation of a large number of energetic and inert substances and compositions
Kane, Abdoulaye. "Conception et caractérisation d’un microcontacteur à film tombant : concept de distillation microstructurée." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL086N/document.
Повний текст джерелаIn many processes of mass transformation, entropic degradations (and energy consumptions which results from) can be minimized by distributing heat flows in all process volume rather than boundaries (example: diabatic distillation). However it is difficult to control and impose thermal gradients on small scales because of their complexity and high costs (exchangers, fluids). This technological difficulty affects not only the performances and energy efficiencies of conventional devices (macro scales) but also small devices (e.g. microstructured reactors). Indeed, compact equipments with small dimensions generate some difficulties. First, the driving force inducing liquid flow by gravity is very small. Second, small size and high thermal conductivity of the material induce thermal homogeneity instead of managing temperature gradients in the system. In many separators, the used packing material has complex forms that make difficult thermal and hydrodynamic structurations. Microstructured devices, based on microchannel plate technologies, offer an interesting possibility of thermal structuration (control and modulation of energy fluxes) and hydrodynamics control (e.g. mass transfer, residence times, pressure drop etc). In this thesis, many discussions on these technological barriers led to the design of a new microstructured falling film contactor. The aim of the present work is to study heat transfer phenomena and liquid hydrodynamics in this device and, investigates the separation feasibility of a binary mixture of ethanol and n-propanol. Microcontactor performances were experimentally evaluated in terms of quality (bottom and top concentrations) and quantity (bottom and top flow rate ratios). To fully characterize contactor performances, the separation power concept (also called compositional exergy) was integrated
Lounaci, Malika. "Systèmes microfluidiques pour la cristallisation des protéines : apports technologiques à la compréhension du processus et influence de la hauteur des canaux." Paris 6, 2009. http://www.theses.fr/2009PA066193.
Повний текст джерелаThe objective of this thesis was to perfect Microfluidic devices for the crystallization of proteins, to offer solutions for the screening of the conditions of crystallization and finally to contribute to understanding the physicochemical process of crystallization in a Microfluidic device. We detailed the techniques of microfabrication, the realization of microvalves as well as the multi-layered chips. A platform allowing the observation of the process of crystallization and the control of microvalves were accomplished. We brought solutions in met problems such as the box divided in two compartments for a better conservation of crystals, the method of aspiration with a minimum of sample without dead volume as well as three-layered chips. Finally, we studied the influence of the height of the microchannel on the crystallization of the lysozyme. We showed that the number of centers of nucleation, the size of crystals as well as the kinetic process of crystallization depends on the height of the channel. We offered, finally, a method of crystallization allowing decoupling the nucleation and crystals growth
Jasiulionis, Jaqueline Andréa Espósito. "Projeto e avaliação de desempenho de torres de resfriamento de água utilizando redes neurais artificiais = Design and analysis of cooling towers using neural netwoks." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266673.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Em muitos processos há necessidade de remover a carga térmica de um dado sistema e utiliza-se, na maioria dos casos, a água como o fluido de resfriamento. Devido à sua crescente escassez e preocupação com o meio ambiente, além de motivos econômicos, a água "quente" que sai desses processos, deve ser aproveitada. Para tanto, ela passa por uma torre de resfriamento e retorna ao processo. Este trabalho descreve um procedimento para avaliar o desempenho térmico de torres de resfriamento, em duas configurações distintas (escoamento contracorrente e escoamento cruzado), utilizando redes neurais artificiais. A vantagem do procedimento proposto é a possibilidade da avaliação direta do desempenho de uma torre sem a complexidade do uso de procedimentos iterativos para convergência nem a necessidade de rotinas de propriedades físicas e psicrométricas. A avaliação do desempenho é feita pela determinação da temperatura de saída da água para um conjunto de parâmetros de entrada (propriedades de corrente da água e do ar na entrada da torre, dimensões e propriedades do recheio), ou determinação da característica do recheio para uma torre existente, em função das condições operacionais. Para a situação de projeto o procedimento permite estimar a vazão de ar ou altura necessária para a torre satisfazer uma condição operacional exigida. O procedimento proposto se mostrou particularmente eficiente para torres com escoamento cruzado, onde o método tradicional de simulação exige a decomposição da torre em um número elevado de células, cada um como um procedimento iterativo para cálculo do balanço de massa e energia. A rede rendeu ótimos resultados quando usada para predizer a temperatura de saída da água e o coeficiente de transferência de massa. Os resultados mostram que a RNA pode fornecer com precisão o desempenho térmico da torre de resfriamento
Abstract: In many industrial environments it is necessary to remove the heat load from a given system and in most cases water is used as the coolant. Due to its increasing scarcity and concerns for the environment, and economic reasons, the "hot" water coming out of these processes must be reused. To do so, it passes through a cooling tower and returns to the process. This paper describes a procedure for evaluating the thermal performance of cooling towers in two different configurations (counter flow and cross flow), using artificial neural networks. The advantage of the proposed procedure is the possibility of direct assessment of the performance of a tower without the complexity due to the required convergence of the iterative procedure or the need for physical properties and psychrometric routines. The performance evaluation is made by computing the temperature of the water outlet for a set of input parameters (flow properties of water and air near the tower, dimensions and properties of the filling), or computing the characteristic of the filling for a existing tower, depending on operating conditions. For the project situation, the procedure allows for the estimate of the air flow or the tower height needed to meet a required operating condition. The proposed procedure proved particularly effective in cross-flow towers, where the traditional method of simulation requires the decomposition of the tower in a large number of cells, each as an iterative procedure for calculating the mass balance and energy. The network yielded excellent results when used to predict the exit temperature of the water and the coefficient of mass transfer. The results show that the RNA can accurately provide the thermal performance of the cooling tower
Mestrado
Sistemas de Processos Quimicos e Informatica
Mestra em Engenharia Química
Munier, Laurent. "Simulations expérimentale et numérique des effets retardés d'une explosion en milieu clos et en présence de produits liquides." Thesis, Aix-Marseille 1, 2011. http://www.theses.fr/2011AIX10091/document.
Повний текст джерелаIs it possible to model collateral effects due to an explosion (on a chemical facility for instance) occuring in a closed volume containing liquid chemical products storage units ?This thesis deals with a zerodimensionnal modelisation of such a 3D complex problem to asses the final thermodynamic state of chemical products released in the atmosphere. Developped sub-models take into account:- the unsteady time histories of the internal overpressure and temperature,- the unsteady liquid ejection (droplets sizes)- the unsteady modelisation of the local heat and mass transfers between the gas phase and the liquid phase- the unsteady ejection process of the resulting multiphase mixture in the environment.Models and sub-models are validated thanks to many experimental results
To, Lap C. "Nonlinear control techniques in alumina refineries." Curtin University of Technology, School of Chemical Engineering, 1996. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12276.
Повний текст джерелаin Alcoa's Kwinana alumina refinery demonstrated the practicability and feasibility of implementing nonlinear control in an industrial setting and also fostered a closer gap between academia and industry. The trials established guidelines for implementing a global linearizing controller on site, including conversion of the relevant constraints and the output of an industrial proportional and integral controller to the equivalent proportional and integral action required by the nonlinear controller. The results showed that the performance of the nonlinear controller was better than the current linear controller on site in terms of responsiveness and resistance to disturbances. Hence, the nonlinear control strategy enables the process to settle faster.All in all, efforts have been made in this thesis to minimise the use of abstract mathematical language and, in some cases, simplify the language so that nonlinear control theory can be understood by a wider range of audience, especially industrial practitioners. It is hoped that the insights provided in the dissertation will encourage more industrial implementations of nonlinear controllers and forge more interaction to close the widening gap between academic and industrial practice in process control.Keywords: nonlinear control, differential geometry, symbolic algebra, evaporator process, uncertainty vector adjustment, geometric nonlinear filter.
Tran, Thanh Danh. "Rôle de la microstructure des sols argileux dans les processus de retrait-gonflement : de l’échelle de l’éprouvette à l’échelle de la chambre environnementale." Thesis, Paris, ENMP, 2014. http://www.theses.fr/2014ENMP0002/document.
Повний текст джерелаThe shrink-swell process of clayey soils is causing damage to the structures during periods of drought. In this thesis, the shrink-swell process of two clayey soils in France that are the Plastic Clays of Sparnacian age and Héricourt clay of Lias is studied at different scales and different conditions (intact, remoulded, compacted and lime treated) by insisting on the role of microstructure. To do this, a part of the study is carried out on the characterisation of soils studied to analyse their mineralogical, microstructural, geotechnical and hydraulic properties in relation with their shrink-swell property. The second part of the study focuses on the analysis of swelling, shrinkage, cracking processes of soil during a single cycle or repeated wetting-drying cycles at specimen scale. The shrink-swell process of soil at a larger scale is studied in the third part by performing infiltration and evaporation tests in the environmental chamber. The results highlight the difference in the shrink-swell behavior at different conditions of soils studied and emphasize the importance of the presence and nature of clay minerals also quartz, hydrates and microstructure of soil to the shrinkage and swelling during water exchange. All changes in the volume of clayey soil during shrinkage and swelling are mainly governed by natural inter-aggregate pores, which are showed by microstructural analyses of MIP and SEM tests
Euhus, Daniel D. "Nucleation in bulk solutions and crystal growth on heat-transfer surfaces during evaporative crystallization of salts composed of NaCO and NaSO." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/5401.
Повний текст джерелаEuhus, Daniel D. "Nucleation in bulk solutions and crystal growth on heat-transfer surfaces during evaporative crystallization of salts composed of Na₂CO₃ and Na₂SO₄." Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180136/unrestricted/euhus%5Fdaniel%5Fd%5F200312%5Fphd.pdf.
Повний текст джерелаSouza, Andr? Luis Rodrigues. "Estabiliza??o de mol?culas bioativas presentes em suco de camucamu (Myrciaria d?bia (H.B.K) Mc Vaugh) pela integra??o dos processos de osmose inversa, evapora??o osm?tica e atomiza??o." Universidade Federal Rural do Rio de Janeiro, 2012. https://tede.ufrrj.br/jspui/handle/jspui/1562.
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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq
Camu-camu is a native fruit from the Amazonian region, cultivated in the margins of rivers, lakes and Amazonian creeks called igarap?s. It is known as one of the fruit with the highest content of vitamin C. Reverse osmosis is a membrane concentration process in which the applied pressure is higher than the juice osmotic pressure. Such process favors the solvent permeation from the region with the highest concentration to the one with the lowest. Osmotic evaporation is another membrane concentration process in which a porous hydrophobic membrane separates the solution that is going to be concentrated from a concentrate brine solution. Microencapsulation is the process in which an active agent is entrapped by means of a polymer cover. Such process promotes the release of these active agents under specific conditions. The aim of this work is to evaluate the use of membrane separation processes and microencapsulation for the processing of camu-camu fruits. The camu-camu pulp, which has been obtained through the depulping of camu-camu fruits, was first centrifuged, in order to decrease its suspended solids content, and clarified by microfiltration with polysulfone membranes. Six clarification processes have carried out at 2.5 bar transmembrane pressure and 45?C. The clarified juice was concentrated by reverse osmosis at 60 bar and 20 ?C. The avarage permeate flux has been of 11.3 L/hm2. The preconcentrated juice had 28.8?Brix and the concentration degree of the process was 3.8. The pre-concentrated juice has been concentrated by osmotic evaporation in a laboratorial system with polytetrafluoroethylene membrane. The process presented an average pemeate flux of 2.4 Kg/hm2. The soluble solids content of the concentrated juice was of 56.6 ?Brix, presenting a concentration degree of 1.98. The retentate fraction of the microfiltration process was microencapsulated in a spray dryer. Three encapsulation agents were evaluated: starch, maltodextrin and the mixture of both. The values presented for the physicochemical caracterization of the pre-concentrated and concentrated camu-camu juices indicate that there has been an increase both in the physical characteristics of the juice, such as soluble solids, total solids and acidity, and in the concentration of camu-camu bioactive compounds. The dehydrated camu-camu juice presented a high concentration of bioactive substances. Nevertheless, there has been no stability of such compounds during storage. Through the results obtained in the present work, it is possible to observe that the integration of membrane processes proved efficient in the concentration of camu-camu juice, with a final product of high nutritional value
O camu-camu ? um fruto nativo da regi?o amaz?nica, cultivado as margens de rios, lagos e igarap?s. ? reconhecido como um dos frutos com um dos maiores teores de vitamina C. Osmose inversa ? o processo de concentra??o por membranas onde a press?o aplicada ? maior que a press?o osm?tica do suco, favorecendo a permea??o do solvente da regi?o de maior concentra??o para regi?o de menor concentra??o. Evapora??o osm?tica ? um outro processo de concentra??o, onde uma membrana hidrof?bica porosa separa a solu??o que ser? concentrada e uma salmoura concentrada. A microencapsula??o ? o processo onde um agente ativo ? protegido por meio de uma cobertura de pol?meros, ocorrendo a libera??o desses agentes ativos em condi??es espec?ficas. O objetivo desta disserta??o foi avaliar o uso dos processos de separa??o com membranas e microencapsulamento para o processamento de suco de camu-camu. Os frutos de camu-camu foram despolpados, sendo o suco submetido a centrifuga??o, com o objetivo de reduzir os s?lidos em suspens?o, e posteriormente clarificado por microfiltra??o em um sistema de membranas de polissulfona. Foram realizados seis processos de clarifica??o a 2,5 bar e 45?C. O suco clarificado foi pr?-concentrado por osmose inversa a 60 bar e 20 ?C. O fluxo permeado m?dio foi de 11,3 L/hm2. O suco pr?-concentrado apresentou teor de s?lidos sol?veis de 28,8?Brix e grau de concentra??o de 3,8. O suco pr?-concentrado foi processado por evapora??o osm?tica em um sistema laboratorial constitu?do por membranas de politetrafluoretileno. O processo apresentou fluxo m?dio permeado de 2,4 kg/hm2. O teor de s?lidos sol?veis do suco concentrado foi de 56,6 ?Brix, apresentando um grau de concentra??o de 1,98. O processo de microencapsula??o da fra??o retida do suco de camucamu foi realizado em um spray dryer Buchi Modelo B-190. Foram realizados tr?s ensaios com tr?s formula??es diferentes: mistura entre amido e maltodextrina, somente amido e somente maltodextrina. Os valores apresentados para a caracteriza??o f?sico-qu?mica do suco de camu-camu pr?-concentrado e concentrado indicam que houve um aumento nos s?lidos sol?veis e totais e da acidez, bem como no teor das subst?ncias bioativas do camucamu. O suco de camu-camu desidratado apresentou alto teor de subst?ncias bioativas, onde a estabilidade desses compostos durante o per?odo de armazenamento n?o foi alcan?ada. Observa-se que a integra??o dos processos com membranas se mostrou eficaz na concentra??o do suco de camu-camu, obtendo um produto com alta qualidade nutricional.
Li, Hailong. "Thermodynamic Properties of CO2 Mixtures and Their Applications in Advanced Power Cycles with CO2 Capture Processes." Doctoral thesis, KTH, Energiprocesser, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9109.
Повний текст джерелаQC 20100819
Mykhailenko, V., and A. Vartansan. "Calculatoin of economic losses of unintentionally produced persistent organic pollutants (POPs) from centralized heating in Odessa." Thesis, Sumy State University, 2016. http://essuir.sumdu.edu.ua/handle/123456789/45338.
Повний текст джерелаТертишник, О. І. "Удосконалення технологічного процесу виготовлення камери випаровування 516.08.001 шляхом застосування високопродуктивної технологічної оснастки". Master's thesis, Сумський державний університет, 2018. http://essuir.sumdu.edu.ua/handle/123456789/72019.
Повний текст джерелаРабота посвящена вопросам проектирования технологического процесса изготовления камеры испарения. Проанализированы технические требования на изготовление детали. Определен тип производства, обоснован способ получения заготовки. Спроектировано станочное приспособление.
The work is devoted to the designing of the technological manufacturing process of evaporation chamber. Technical requirements for the manufacture of part was analyzed. The type of production was determined, the method for producing the blank was justified. The fixture was designed.
Kuchi, Venkateswarlu. "Development of an innovative ISOL system for the production of short-lived neutron-deficient ions." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC233/document.
Повний текст джерелаIn the frame of GANIL/SPIRAL-1 facility, an innovative target ion source system (TISS) has been designed in order to produce new competitive radioactive ion beams, and to determine to which extent it is possible to improve the production performances by optimizing a target ion source system dedicated to the production of a specific radioactive ion beam.The short-lived alkali isotope of 74Rb (half-life = 64.8 ms) has been chosen as a challenging case study.By studying and improving the processes involved in the TISS designed, i.e. in-target production by fusion-evaporation, implantation in and release out of graphite, effusion, and ionization, an atom-to-ion transformation efficiency of 75% was predicted, leading to an ion rate of the order of 104 pps at the exit of the TISS.The estimated performances would allow the GANIL / SPIRAL-1 installation to deliver beams of 74Rb and 114Cs with competitive intensities never reached in other installations.The production device was developed based on my work, to cope with physics objectives and with the conditions of the SPIRAL-1 operation. Efficiency, reliability and thus simplicity were essential. The system meets these requirements.The instrumentation needed for tests existed or have been specifically designed. The TISS has been built, assembled and partly tested.In parallel, issues have been addressed to answer related questions about sticking times, resistivity, and emissivity, to get inputs for the design of the TISS.Expected results with alkali allow thinking that the transposition of the principle to the production of neutron-deficient short-lived isotopes of noble gases and eventually metals could be performing
Diel, Cristiano Luiz. "Modelagem matemática do processo de evaporação do licor negro proveniente do sistema de lavagem da polpa celulósica." Universidade Estadual do Oeste do Parana, 2013. http://tede.unioeste.br:8080/tede/handle/tede/1851.
Повний текст джерелаKlabin Fabricadora de Papel e Celulose S/A
The pulp and paper industries are major consumers of energy. The plant of black liquor evaporation consumes significant portion of this energy. Any effort to improve their energy efficiency is beneficial to the industry. The computer simulation is a powerful tool to aid the understanding of industrial processes and may help identify mechanisms involved in the prediction of responses to changes in operating conditions and optimization of process control. The objective of this work is the development of a mathematical model phenomenological representing the evaporation plant of Klabin Papéis Monte Alegre (KPMA) and the use of it to study and improve operational conditions of the plant. To achieve this goal, firstly it was developed a simplified model based on the work of other authors. The model was built in Maple ® platform. The model was built from mass and energy balances and phase equilibrium equations. Correlations were used to estimate properties, e. g. boiling point raise, enthalpies of the liquor, steam and condensate. The model reproduced well the results of the authors, with the largest percentual error equal to 5.5% and most of the parameters with percentual errors less than 1%. The model was adapted to represent the first effect of evaporation plant of KPMA. Historical operating data were used to compare the model results. Good results were found for temperature and solid content of the liquor. Good results were found for mass flows in some effects, but the model could not effectively predict the mass flow of all effects and the variables related to the flash tanks. The differences are attributed mainly to considerations of steady state and saturated vapor with no entrainment of particles in the liquor and the use of literature correlations to predict the properties of the liquor that do not correspond to the liquor used.
As indústrias de papel e celulose são grandes consumidoras de energia. A planta de evaporação de licor negro consome parte significativa dessa energia. Qualquer esforço no sentido de melhorar sua eficiência energética é benéfico para a indústria. A simulação computacional é uma ferramenta poderosa no auxílio da compreensão de processos industriais, podendo auxiliar na identificação de mecanismos envolvidos no processo, na predição de respostas a mudanças de condições de operação e na otimização do controle de processos. Assim, o objetivo do presente trabalho é o desenvolvimento de um modelo matemático fenomenológico representando a planta de evaporação da Klabin Papéis Monte Alegre (KPMA) e a utilização do mesmo para estudo e melhoria das condições operacionais da planta. Para atingir a este objetivo, primeiramente foi desenvolvido um modelo simplificado baseado no trabalho de outros autores. O modelo foi construído em plataforma Maple®. O modelo foi construído a partir de balanços de massa e energia e equações de equilíbrio de fases. Foram utilizadas correlações para estimar propriedades, e.g. elevação do ponto de ebulição, entalpias do licor, vapor e condensado. O modelo reproduziu bem os resultados dos autores, sendo o maior desvio percentual igual a 5,5% e a grande maioria dos parâmetros com desvio percentuais inferiores a 1%. O modelo foi adaptado para representar o primeiro efeito da planta de evaporação da KPMA. Dados históricos de operação foram utilizados para comparação dos resultados do modelo. Foram encontrados bons resultados para os teores de sólidos e temperaturas do licor, bem como para as vazões para alguns dos evaporadores. O modelo não pôde predizer com eficácia as vazões de todos os evaporadores e das variáveis referentes aos tanques de expansão de licor. As diferenças encontradas são atribuídas principalmente às considerações de regime estacionário e de vapor saturado com ausência de arraste de partículas no licor, bem como da utilização de correlações da literatura para predizer as propriedades do licor que não correspondem ao licor utilizado na evaporação.
Buckley-Smith, Marion. "The Use of Solubility Parameters to Select Membrane Materials for Pervaporation of Organic Mixtures." The University of Waikato, 2006. http://hdl.handle.net/10289/2625.
Повний текст джерелаAusmeel, Erik, and Botvid Gannholm. "Dataanalys av en ny avfrostningsrutin på en kyl- och frysanläggning : En studie gjord hos Freezing Food Småland Öland AB." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-105008.
Повний текст джерелаThis report is about a change in the food company Freezing Food Småland Öland AB’s defrosting routine for their evaporators in the freezer warehouse. The change was that the defrosting time and maximum temperature were reduced and that the time between defrostings now takes place every other night instead of every night. The aim was to examine whether the change in the routine had contributed to a reduction in energy consumption compared to before the change was made by also examining factors other than defrosting itself that might affect energy consumption. The method was to collect and analyze large amounts of data provided by the company and then reduce them to manageable figures. Data for local outdoor temperatures were also collected. This calculated averages for a given time period for energy consumption, warehousing and outdoor temperature. The results showed a decrease in energy consumption, the proportion due to the change in defrosting procedures left the investigation unanswered. The outdoor temperature should have reduced the power requirement, at the same time the storage should have increased it. It was concluded that more time needed to pass,and a new study needed to be produced after the defrosting routine was changed to allow for a safer assessment.
Lahondère, Chloé. "Stress thermique et thermorégulation chez lez insectes hématophages." Thesis, Tours, 2012. http://www.theses.fr/2012TOUR4029.
Повний текст джерелаInsects are submitted to thermal fluctuations of their environment and have developed a wide ranged panel of behavioral, physiological and biochemical responses, to minimize the subsequent deleterious effects and maintain their physiological integrity. Some species actively regulate their internal temperature independently of the temperature of the environment. If these insects can overcome the constraints imposed by their thermal environment, those that feed on warm-blooded vertebrate hosts have no choice but to confront a situation of thermal stress at each feeding event. The main objective of this work is to understand how bloodsucking insects manage heat stress associated with the massive flow of heat generated by the ingestion of the blood meal. Our results show these insects have developed different strategies of thermoregulation to protect themselves from overheating
Apicella, Fernandez Sergio. "Surface energy modification of metal oxide to enhance electron injection in light-emitting devices : charge balance in hybrid OLEDs and OLETs." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-25097.
Повний текст джерелаWestin, Elin M. "Microstructure and properties of welds in the lean duplex stainless steel LDX 2101." Doctoral thesis, KTH, Metallografi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-27387.
Повний текст джерелаQC 20101213
Martínez, Galván Israel Octavio. "Estudio experimental de optimización de una bomba de calor agua-agua empleando propano como fluido de trabajo." Doctoral thesis, Universitat Politècnica de València, 2008. http://hdl.handle.net/10251/3344.
Повний текст джерелаMartínez Galván, IO. (2008). Estudio experimental de optimización de una bomba de calor agua-agua empleando propano como fluido de trabajo [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/3344
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