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Hydrodynamický model Svitavy a Svratky na území města Brna / Hydrodynamic model of the Svitava and Svratka rivers in BrnoRačoch, Tomáš January 2019 (has links)
The Master‘s thesis deals with the assessment of the current state of flood protection in the rivers and floodplains of Svitava (km 0.000 - 2,050) and Svratka (km 26,370 - 33,963) in Brno. Using a combined 1D and 2D numerical model of water flow, hydraulic calculations of the peak flows of Q5, Q20 and Q100 were performed. For calculation, HEC-RAS 5.0.6 was used. The outputs were processed in the form of flood hazard maps and drawing documentation.
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Změny proteinového profilu v průběhu sladování ječmene / Changes of protein profile in barley during maltingŠopíková, Martina January 2008 (has links)
This diploma thesis is focused on studies of changing of protein profile during barley malting. Substantial part of this work is devoted to the proteomics identification of barley proteins which change during malting and so become more stationary and they influence quality of beer (haze and foam in beer). For this experiment was used barley variety Jersey. In the theoretical part of this thesis there is information about beer, manufacturing of beer with description of important commodities for manufacturing of beer and information about barley malting and information about malting process. Next there is description of methods for separation of proteins (1D gel electrophoresis and 2D gel electrophoresis), MALDI TOF/TOF mass spectrometry and this use for the analysis and identification of proteins, the use of matrices and ways of the sample preparation. In the experimental part of this thesis there was carried out the optimisation of the dosage of sample for 1D gel electrophoresis and the optimisation of staining. The 15 % TRIS-HCl gel was the best, this gel was stained by Commassie Brilliant Blue G-250. For illustration of changes was made 2D gel electrophoresis. With help of method peptide mass fingerprinting and MS/MS protein of barley – protein Z, -amylase subtilisin inhibitor, -amylase a peroxidase were identificated. The analysis of barley extract intact proteins was carried out, this analysis was focused on changes of important barley protein LTP 1.
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Hydraulické posouzení vlivu revitalizace vodního toku na retenční kapacitu údolní nivy / Hydraulic assessment of a stream revitalization effect on a floodplain retention capacityBerka, Ondřej January 2015 (has links)
Diploma thesis “Hydraulic Assessment of a Stream Revitalization Effect on a Floodplain Retention Capacity“ assess availability of revitalized stream and its floodplain to transform floods and compare determined values with transformed floods from model of technically modified stream, both by using coupling 1D/2D BASEMENT computational model. In the first part is overall introduction to research issue. In the second part the territory of interest is described and the hypothesis are set. In the third part are described input data, used tools, computational model, its making and computational versions. In the fourth part the hypothesis are evaluated. It was determined, that for in this thesis used terrain and hydrographs are floods smaller than Q20 transformed much more by revitalized stream and that technically modified stream can speed up the flood, floods Q50 and Q100 are more transformed by technically modified stream. For generalization of the results would be appropriate to make research on bigger ammount of case studies based on combination of 1D/2D and rainfall-runoff model.
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Návrh sportovních vaček pro motocyklový motor / Design of sport cams for motorcycle engineZávodník, Michal January 2015 (has links)
The master thesis contains a theoretical part with the topic of valve train. It contains measured data and their processing. The processed data are used to create the 1D engine’s simulation. Valve train’s parameters were modified for increased power and torque. Contained two variants of changes can serve as guide for final draft because of next adjustments.
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Studie protipovodňových opatření v lokalitách Komín a Kníničky na Svratce / Feasibility study of the flood protection measures in the localities of Komín and Kníničky at the Svratka riverŠťastová, Barbora January 2017 (has links)
The aim of master‘s thesis is to assess the current state of the degree of flood protection on the basis of hydraulic calculations for different flood scenarios that correspond to the maximum culmination discharges Q1, Q5, Q20, Q100, Q100 unaffected in areas Komin and Kníničky on the Svratka at km 45.477 to 47.810. Hydraulic calculations were carried out using the coupled 1D and 2D numerical model. The outputs have been processed in the form of maps of depths and speed floodings.
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Scalable 1D and 2D polymer-based nanoparticles via crystallization-driven self-assemblyEllis, Charlotte Emily 21 April 2022 (has links)
Self-assembly is ubiquitous in nature. A diverse range of materials with exceptional properties are accessed from a limited number of sub-units, through controlling structural order on all length-scales. Achieving the same level of control to access functional materials akin to those in nature is a key challenge in chemistry. Self-assembly of block copolymers (BCPs) offers a valuable bottom-up route, governed by non-covalent interactions, to access ordered assemblies on the nanoscale. Anisotropic nanostructures, such as one- and two-dimensional (1D and 2D) micelle morphologies, are of particular interest for various applications including those in biomedicine, catalysis, optoelectronics, and materials engineering. Crystallization-driven self-assembly (CDSA) of BCPs containing a crystallizable core-forming segment presents a robust route to preparing 1D and 2D micelles. Significantly, the use of pre-existing seed micelles in a process termed living CDSA allows access to 1D and 2D nanostructures of controlled size and low size-dispersity. Although CDSA protocols represent powerful tools for the formation controlled 1D and 2D nanostructures, key challenges associated with scale-up of these processes remain. In most cases, increasing the concentration at which living CDSA is performed results in competitive self-nucleation, compromising micelle size-control and dispersity. Living polymerization-induced crystallization-driven self-assembly (PI-CDSA) has been presented as a promising alternative route to accessing scalable 1D micelles. In this case, the polymerization, self-assembly, and seeded growth of a BCP containing a crystallizable core-forming segment occur in situ. However, the scope of living PI-CDSA is currently limited to the use of polyferrocenylsilane (PFS)-based BCPs. Owing to the diverse range of crystalline core chemistries compatible with CDSA protocols, and therefore various promising applications of 1D and 2D micelles, scale-up is essential to facilitate their further investigation and application. The work presented in this thesis focusses on upscaling the preparation and processing of controlled 1D and 2D micelles with a crystalline core. The scalable preparation of low dispersity 2D platelet micelles by living CDSA of a charge-terminated PFS homopolymer with surfactant counteranions is presented in Chapter 2. Here, fundamental insight into the effects of living CDSA concentration on platelet dimensions, structure fidelity, and aggregation behaviour is provided. In Chapter 3, the scope of living PI-CDSA is extended to access scalable length-controlled low dispersity 1D nanofibers containing a biodegradable poly(fluorenetrimethylenecarbonate) (PFTMC) crystalline core. PFTMC-based 1D fibers are of interest for biomedical applications, hence, in this work, it is demonstrated that living PI-CDSA can be used to prepare fibers exhibiting biologically-relevant lengths at scalable concentrations. In Chapter 4, the scalable formation of low dispersity 1D micelles by living CDSA of a PFS-based BCP in a continuous flow setup is explored. Processing of 1D micelles into microfibers using simple, low cost, and high throughput electrospinning techniques is demonstrated in Chapter 5. Finally, Chapter 6 summarises the contribution of this thesis to improving the scalability of CDSA protocols and provides future directions for this work. / Graduate / 2023-04-12
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Integrated nano-optomechanics in photonic crystal / Nano-optomécanique intégrée dans les cristaux photoniquesZhu, Rui 16 September 2019 (has links)
Les oscillateurs de référence de haute pureté sont actuellement utilisés dans un grand nombre d’applications allant du contrôle de fréquence aux horloges pour les radars, les GPS et l’espace... Les tendances actuelles dans ce domaine requièrent des architectures miniaturisées avec la génération de signaux directement dans la gamme de fréquences d’intérêt, autour de quelques GHz. Récemment, de nouvelles architectures basées sur les principes de l’optomécanique ont vu le jour dans ce but. De tels oscillateurs optomécanique génèrent non seulement des signaux hyperfréquences directement dans la gamme de fréquences GHz avec éventuellement un faible bruit de phase, mais permettent également un degré élevé d'intégration sur puce. Ce travail de thèse s'inscrit dans cette démarche. L’oscillateur optomécanique étudié se compose de cavités à cristaux photoniques suspendues couplées à des guides d’ondes silicium sur isolant intégrés dans une architecture tridimensionnelle. Ces cavités abritent des modes optiques fortement confinés autour de 1550nm et des modes mécaniques dans le GHz. De plus, ces structures présentent un recouvrement spatial entre phonon et photon élevé. Il en résulte un couplage optomécanique amélioré. Cette force de couplage optomécanique améliorée est ici sondée optiquement sur des structures à cristaux photoniques de conception optimisée. Ces cavités sont réalisées dans des matériaux semi-conducteurs III-V dont la piézoélectricité nous permet d'intégrer des outils supplémentaires pour sonder et contrôler les vibrations mécaniques via un pilotage capacitif, piézoélectrique ou acoustique. Ce contrôle total des modes mécaniques et de l’interaction optomécanique ouvre la voie à la mise en œuvre de circuits intégrés pour le verrouillage par injection et des boucles de rétroaction permettant de réduire le bruit de phase de l’oscillateur. / High purity reference oscillators are currently used in a wide variety of frequency control and timing applications including radar, GPS, space... Current trends in such fields call for miniaturized architectures with direct signal generation in the frequency range of interest, around few GHz. Recently, novel optomechanically-enhanced architectures have emerged with this purpose. Such optomechanically-driven oscillators not only generate microwave signals directly in the GHz frequency range with possibly low phase noise but also are amenable to a high degree of integration on single chip settings. This PhD work falls within this scope. The optomechanically-driven oscillator under study consists of suspended photonic crystal cavities coupled to integrated silicon-on-insulator waveguides in a three-dimensional architecture. These cavities harbor highly-confined optical modes around 1,55 µm and mechanical modes in the GHz and most importantly, feature a high phonon-photon spatial overlap, all resulting in an enhanced optomechanical coupling. This enhanced optomechanical coupling strength is here probed optically on photonic crystal structures with optimized design. These cavities are hosted in III-V semiconductor materials whose piezoelectricity enable us to integrate additional tools for probing and controlling mechanical vibrations via capacitive, piezoelectric or acoustic driving. This full control over the mechanical modes and optomechanical interaction, paves the way towards the implementation of integrated injection locking circuits of feedback loops for reducing the phase noise of the oscillator.
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Development of an Installation to Emulate Altitude, Ambient Temperature, and Ambient Humidity on Thermal Engines. Application to the Study of the Impact over E6 Engine PerformanceTabet Aleixandre, Roberto 27 June 2022 (has links)
[ES] Las normativas cada vez más restrictivas sobre las emisiones contaminantes de los vehículos de motor impuestas por la Unión Europea han obligado a los fabricantes de equipos originales (OEM) a proporcionar a los centros de investigación herramientas e instalaciones que pueden reproducir de forma precisa y repetida diferentes condiciones atmosféricas durante las primeras etapas del desarrollo del motor. En la actualidad la legislación europea incluye pruebas de emisiones reales en conducción (RDE) en diferentes condiciones atmosféricas, con altitudes de hasta 1300 metros sobre el nivel del mar y temperaturas que alcanzan los -7 ºC. Esto se ha hecho típicamente utilizando cámaras climáticas y altimétricas que permiten la reproducción de las condiciones atmosféricas en toda la celda de prueba, y más recientemente conectando a motor simuladores de altitud acoplados con unidades de tratamiento de aire (AHU).
En esta Tesis Doctoral, se presenta la mejora del simulador de altitud comercializado por la empresa HORIBA denominado MEDAS, utilizando procedimientos tanto inductivos como deductivos, con el objetivo de ampliar el rango de prestaciones de la instalación, así como mejorar la precisión del control de la presión del aire comburente y reducir el consumo energético global. Además, durante esta fase, se lleva a cabo el desarrollo de un modelo 1D del simulador de altitud, con el que es posible obtener resultados precisos sobre el desempeño de la instalación para diferentes condiciones de contorno, como puede ser el punto operativo del motor, la presión de la sala o la temperatura del agua de refrigeración.
A continuación, se han desarrollado dos nuevos equipos: el Módulo de Temperatura del MEDAS (MTM) y el Módulo de Humedad del MEDAS (MHM); mejorando las estrategias de control y algunos componentes clave (por ejemplo, la columna de agua de burbujas) para controlar con precisión la temperatura y la humedad del aire de combustión. Estos dos junto con el MEDAS crean un simulador de atmósfera completo, que permite el control independiente de las tres variables psicrométricas del aire de combustión del motor: presión, temperatura y humedad.
Por último, el simulador de atmósfera desarrollado se utiliza para estudiar el efecto que las tres variables psicométricas del aire ambiente tienen sobre el rendimiento y las emisiones contaminantes de un motor Diesel Euro 6 turboalimentado, demostrando el gran efecto que tiene la humedad ambiental sobre las emisiones contaminantes de los motores Diesel y la necesidad de considerar este parámetro en las estrategias de calibración. Algunos resultados obtenidos podrían ser la reducción de potencia que el motor sufre al operar en condiciones de altitud, los cambios que la temperatura ambiente causa en el punto de operación del turbo grupo o como las emisiones de NOx se reducen cuando la humedad ambiente aumenta. / [CA] Les normatives cada vegada més restrictives sobre les emissions contaminants dels vehicles de motor imposades per la Unió Europea han obligat als fabricants d'equips originals (OEM) a proporcionar als centres d'investigació eines i instal·lacions que poden reproduir de manera precisa i repetida diferents condicions atmosfèriques durant les primeres etapes del desenvolupament del motor. En l'actualitat la legislació europea inclou proves d'emissions reals en conducció (RDE) en diferents condicions atmosfèriques, amb altituds de fins a 1300 metres sobre el nivell de la mar i temperatures que aconsegueixen els -7 °C. Això s'ha fet típicament utilitzant cambres climàtiques i altimètriques que permeten la reproducció de les condicions atmosfèriques en tota la cel·la de prova, i més recentment connectant a motor simuladors d'altitud acoblats amb unitats de tractament d'aire (AHU).
En aquesta Tesi Doctoral, es presenta la millora del simulador d'altitud comercialitzat per l'empresa HORIBA denominat MEDAS, utilitzant procediments tant inductius com deductius, amb l'objectiu d'ampliar el rang de prestacions de la instal·lació així com millorar la precisió del control de pressió de l'aire de combustió i reduir el consum energètic global. A més, durant aquesta fase, es du a terme el desenvolupament d'un model 1D del simulador d'altitud, amb el qual és possible obtindre resultats precisos sobre l'acompliment de la instal·lació per a diferents condicions de contorn, com pot ser el punt d'operació del motor, l'altitud d'instal·lació o la temperatura de l'aigua de refrigeració.
A continuació, s'han desenvolupat dos nous equips: el Mòdul de Temperatura del MEDAS (MTM) i el Mòdul d'Humitat del MEDAS (MHM); millorant les estratègies de control i alguns components clau (per exemple, la columna d'aigua de bambolles) per a controlar amb precisió la temperatura i la humitat de l'aire de combustió. Aquests dos juntament amb el MEDAS creen un simulador d'atmosfera complet, que permet el control independent de les tres variables psicromètriques de l'aire de combustió del motor: pressió, temperatura i humitat.
Finalment, el simulador d'atmosfera desenvolupat s'utilitza per a estudiar l'efecte que les tres variables psicomètriques de l'aire ambient tenen sobre el rendiment i les emissions contaminants d'un motor Dièsel Euro 6 *turboalimentado, demostrant el gran efecte que té la humitat ambiental sobre les emissions contaminants dels motors Dièsel i la necessitat de considerar aquest paràmetre en les estratègies de calibratge. Alguns resultats obtinguts podrien ser la reducció de potència que el motor pateix en operar en condicions d'altitud, els canvis que la temperatura ambient causa en el punt d'operació del turbo grup o com les emissions de NOx es redueixen quan la humitat ambiente augmenta. / [EN] Increasingly restrictive regulations on pollutant emissions for motor vehicles imposed by the European Union have forced original equipment manufacturers (OEMs) to provide research centers with tools and facilities that can accurately and repeatedly reproduce different atmospheric conditions during the early stages of engine development. Nowadays, the European legislation includes real driving emissions (RDE) tests at different atmospheric conditions, with altitudes up to 1300 meters above sea level and temperatures reaching -7 ºC. This has been done typically using altimetric and climatic chambers, which allow the reproduction of the atmospheric conditions in the whole test cell. More recently, connecting to the engine altitude simulators coupled with air handling units (AHU).
In this Ph.D. Thesis, the improvement of the altitude simulator commercialized by the company HORIBA called MEDAS, carried out by inductive and deductive procedures, is presented to extend the installation's performance range, improve the combustion air pressure control accuracy, and reduce the installation global energy consumption. Furthermore, during this phase, the development of a 1D model of the altitude simulator is carried out, with which it is possible to obtain accurate results about the performance of the installation for different boundary conditions such as the engine operation point, the room pressure, or the cooling water temperature.
Following, two new pieces of equipment have been developed: MEDAS Temperature Module (MTM) and MEDAS Humidity Module (MHM), improving the control strategies and some key components (i.e., the bubbles water-column) to increase the accuracy of the combustion air temperature and humidity control. Together with the MEDAS, these two create a complete atmosphere simulator, which allows the independent control of the three psychrometric variables of the engine combustion air: pressure, temperature, and humidity.
Lastly, the atmosphere simulator developed is used to study the effect that the three psychometric variables of the ambient air have on the performance and the pollutant emissions of a Euro 6 turbocharged diesel engine, proving the significant effect that the ambient humidity has on the diesel engines pollutant emissions and the necessity of considering this parameter in the calibration strategies. Some results could be the reduction in power that the engine suffers when operating in altitude conditions, the changes that the ambient temperature causes at the turbocharger operative point, or the decrease in NOx emissions that happen when the ambient humidity increases. / Tabet Aleixandre, R. (2022). Development of an Installation to Emulate Altitude, Ambient Temperature, and Ambient Humidity on Thermal Engines. Application to the Study of the Impact over E6 Engine Performance [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/183753 / TESIS
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Theoretical and numerical tools for studying the Critical Zone from plot to catchmentsTubini, Niccolò 14 October 2021 (has links)
After the seminal works by Freeze and Harlan (1969), the scientific community realized that groundwater and vadose zone equation were breaking up. Hydrologists split into three communities following the motto “you are my boundary condition”: groundwater people, vadose zone scientists and surface water hydrologists. This compartmentalization of the scientific community fostered a deepening of knowledge in single branches, allowing to break things down into simple parts. However, this division represented an obstacle to the comprehension of the complexity that characterises the interactions between them. Eventually, this separation of the communities continued into software code. As a matter of fact, the boundary conditions were hard-wired, but they offered a poor representation of the physics in the interaction between different domains. Recently, there has been a renewed interest in studying the big picture, the interactions between different domains. This it is evident in the development of a new research field named the Earth’s Critical Zone (CZ). It is defined as the “ heterogeneous, near surface environment in which complex interactions involving rock, soil, water, air, and living organism regulate the natural habitat and determine the availability of life-sustaining resources” (National Research Council, 2001). Further interest in the studying the CZ is given by the ever-increasing pressure due to the growth in human population, wealth, and climatic changes. This thesis focuses on the CZ while recognising the central role of having a solid set of tools for modeling the water movements in all conditions. Recently, Prentice et al. (2015) identified Reliable, Robust, and Realistic, the three R’s, as the three characteristics that numerical models should have. Soil moisture is one of the key components to simulate the processes in the critical zone. The governing equation to describe the water flow in a porous material is know as the Richards equation and it dates back to 1931.The numerical solution of the Richards equation is far from trivial because of its mildly nonlinearity and it is often discarded in favour of more empirical models. After the pioneering work by Celia et al. (1990), a lot of work has been done in this direction and several model, for instance Hydrus, GEOtop, Cathy, Parflow adopted variants of the Newton algorithm to allows global convergence. Since Casulli and Zanolli (2010), anticipated by Brugnano and Casulli (2008), a new method called nested Newton has been found to guarantee convergence in any situation, even under the use of large time steps and grid sizes. The research presented in this thesis used this integration algorithm. Besides the numerical aspect, another issue was the correct definition of the boundary condition at the soil surface. As a matter of fact, the definition of the surface boundary condition is necessary to capture the generation of surface run-off. In the literature several approaches were proposed to couple surface and subsurface flow, and in this work the approach presented by Gugole (2016) has been used. The novelty regarded the discretization of the shallow water equation and the Richards equation in an unique algebraic system that was solved in a conservative manner. Richards equation was criticized from many points of view, but it is difficult to criticize its core mass conservation. The definition of the hydraulic properties of the soil, including both the soil water retention function (SWRC) and the hydraulic conductivity models, often uses simplified representation of the pore system describing it as bundle of cylindrical capillaries where the largest ones drain first and are filled last. As pointed out by Bachmann et al. (2002), “physical effects, like surface water film adsorption, capillary condensation and surface flow in liquid films, as well as volumetric changes of the pore space are often ignored”. Thus, the capillary bundle concept is a rough, even if still useful approximation of soil reality. From these observations, during the research the code has been designed to offer the opportunity to easily implement new soil water hydraulic models that might be proposed in the future. The Richards’ equation alone is not anymore sufficient to model the water flow in soils. In fact, soil temperature affects the water flow in soils. This is evident in cold regions where soil water is subject to freezing and thawing processes, but also in unfrozen soil, where temperature modifies water properties such as viscosity, the surface tension, and the contact angle. These microscopic variations of the water physical properties have significant impacts in the mass and energy budget within the CZ. For instance, it has been observed that the infiltration rates between the stream and the vadose zone show a clear diurnal pattern: infiltration rates are highest in late afternoon, when stream temperature is greatest, and they are lowest in early morning when stream temperature is least. In cold regions the run-off production is strongly affected by the presence of ice with the soil. Nonetheless, soil moisture modifies the thermal properties of the soil: water is characterised by a high thermal inertia and the thermal conductivity of ice is almost four times larger than that of liquid water, and water flow carries a significant amount of sensible heat. These aspects come under one the R of realistic. Hence, the Richards’ equation has been coupled with the energy equation for the unfrozen case. Moreover, the research developed a model to study the heat transfer considering the phase change of water. In both cases robust numerical schemes have been used. There are few models that already coupled the equations. One of these models is GEOtop that was conceived and built in the research group where this work was carried out. Such models have some limitations. One of the main limitations regards their implementations. In fact, these models were built as a monolithic code and this turns in difficulties in maintaining and developing existing codes. In this work the codes have been developed by using Design Patterns. As a result, the codes are easy to maintain, to extend, and to reuse. Considering the CZ, these aspects are of crucial importance. Researchers should have a model that can be extended to include more processes, i.e. increase its complexity and avoiding the code to become too complicated. The models were integrated in the Object Modelling System v3 (OMS3) framework. The system provides various components for precipitation treatment, radiation estimation in complex terrain, evaporation and transpiration that can be connected to each other’s for generating inputs and outputs. Due to the modularity of the system, whilst the components were developed and can be enhanced independently, they can be seamlessly used at run time by connecting them with the OMS3 DSL language based on Groovy. OMS3 provides the basic services and, among them, tools for calibration and implicit parallelization of component runs. In sum, the thesis analyses the relevant literature to date. It presents a detailed description of the physical processes related
to the water flow and the energy budget within the soil. Then, it describes the numerical method used to solve and coupled the equations. It also provides the informatics behind WHETGEO 1D (Water HEat Tracers in GEOframe). Finally, the work focuses on the WHETGEO extension for the bidimensional case by showing how the code can be designed to store grid information.
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Three-way catalyst calibration and system modelling for CNG engine exhaust aftertreatment / Kalibrering av trevägskatalysator och systemmodellering för avgasefterbehandling med CNG-motorParikh, Khyati January 2022 (has links)
Detta projekt behandlar metodutveckling för att modellera en trevägskatalysator som skulle kunna användas vidare för att uppskatta utsläppen från en Ottomotor. Modellen är byggd i AVL Cruise M för att bestämma omvandlingarna för de tre lagstiftade föroreningarna kolmonoxid, kväveoxider (NOx) och metan baserat på reaktioner som sker i trevägskatalysatorer. Projektet tar också upp olika experimentella metoder och specifika kalibreringsmetoder som används för att samla in data och bygga modellen. Projektet diskuterar två olika kalibreringsprocesser baserade på insamlade experimentella data och antalet reaktioner kalibrerade i varje steg. Dessutom diskuteras programvaran som används och ändringarna som gjorts i den fördefinierade modellen av programvaran. Resultatet efter kalibreringen visade att den andra kalibreringsprocessen gav bättre resultat, men vissa avvikelser observerades i den byggda modellen. Avvikelserna antas bero på följande tre anledningar. För det första, försummar ytreaktionsmodellen föroreningarnas diffusionshastigheter. Dessutom kan komplexiteten hos objektfunktionen som matas in i optimeraren samt de stationära data som används för kalibreringsändamål också ge avvikelser. Dessa tre argument testas i projektet och slutsatserna som dras för att kunna förbättra modellen är följande. Objektfunktionen behöver förenklas så mycket som möjligt, diffusion av föroreningar genom washcoaten kan inkluderas i olika komplicerade steg och syrelagringsreaktioner blir viktiga när man tar hänsyn till transienta förhållanden. / This project discusses about development of a method to model the three-way catalyst which could be used further to estimate the emissions from an Otto engine. The model is built in the commercial software called AVL Cruise M to determine the conversions of three legislative pollutants namely, carbon monoxide, nitrogen oxide and methane based on reactions occurring within the three-way catalyst. The project also discusses about different experimental and calibration methods used for collecting the data and building the model. The project discusses two different calibration process based on the experimental data used and number of reactions calibrated on each step. Furthermore, the software used, and the modifications made in the predefined model of the software are also discussed. The result after the calibration showed that the second calibration process gave better results, but some deviations were observed in the model built. The deviations are assumed to be because of three arguments present. Firstly, considering the surface reaction model which neglects the diffusion rates of the species. Secondly, the complexity of the objective function fed into the optimiser. The optimiser is also a software by AVL named design explorer which helps to optimise the parameters. And thirdly, the use of steady state data only and not including transient conditions for the calibration purposes. These arguments are tested in the project, and it is concluded to improve the model, the objective function needs to be simplified as much as possible, diffusion of species through washcoat could be considered at advance stages and oxygen storage reactions become important when transient conditions are taken into consideration.
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