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Optimalizace chlazení koncentrátorového fotovoltaického článku pomocí systémů CAE / Optimization of cooling the photovoltaic cell using CAE systemsSodomka, Pavel January 2014 (has links)
This thesis deals with the optimization of the concentrate photovoltaic cell cooling system through the CAE system. In the theoretical part, the thesis treats there the problematic of the photovoltaics and focuses on the concentrator cell and its problems coupled with the cooling system and the sink of heat. In the next theoretic part, it also analyses there the problematic of the conduit and transfer of heat. Moreover, the mathematical description of the fluid flow, the finite-volume method that is used in the SolidWorks Flow Simulation for the calculations, are also described there. In the practical part, the models and steps which depict precisely all the process of the heat cooling optimization are mentioned. All the proposed variants are mutually compared and put up for the discussion about their advantages and disadvantages. Lastly, the resultant model was also put through the simulation with the suggested radiational component that gave precision to the results. In the end of the thesis, there was made out the documentation of the final model drawings.
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Solární koncentrátorový systém s automatickým natáčením / Solar Concentrator System with Automatic Tracking SystemŽák, Martin January 2017 (has links)
This master’s thesis is focused on current possibilities of solar energy utilization – especially on concentrating solar power systems – and their optimization using solar tracking systems to maximize energy gain. The thesis also deals with solar position algorithm and offers an Arduino based automatic dual axis solar tracker design which provides various solar devices the ability to pivot using stepper motors, DC motors or servos. The motion might be driven by calculated solar position or by actual illuminance.
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Primena modifikovanog bentonita kao katalizatora u Fenton i foto-Fenton procesu uklanjanja tekstilne reaktivne boje / Application of modified bentonite as catalyst in Fenton and photo-Fenton removal process of textile reactive dyePucar Milidrag Gordana 13 August 2019 (has links)
<p>Cilj ovog rada bio je ispitivanje mogućnosti primene modifikovanog bentonita kao katalizatora (ferioksalat i Al, Fe-bentonit katalizatori) u Fenton i foto-Fenton procesu uklanjanja tekstilne reaktivne boje Reactive Red 120. Do sada su objavljene studije primene heterogenog Fenton procesa sa različitim koncentracijama gvožđau katalizatorima i sa kompleksom ferioksalata,međutim, njihovo poređenje u smislu efikasnosti obezbojavanja nije istraženo, što je bio jedan od fokusa istraživanja u ovom radu. Osim toga, potencijal sunčeve energije predstavlja 16,7% od ukupno iskoristivog potencijala obnovljivih izvora energije u Srbiji, dok je prosečno sunčevo zračenje u Srbiji oko 40% više od evropskog proseka, čineći ga vrlo zanimljivim za primenu u ovom tipu tretmana. U cilju što boljeg iskorišćenjasunčevog zračenja i unapređenja fotokatalitičkih performansi procesa primenjen je parabolični koncentrišući reaktor, koji je za ovu vrstu procesa prvi put upotrebljavan. Proučavano je u kojoj meri je solarna fotokataliza značajan segment tehnike za tretman otpadnih voda tokom degradacije perzistentnih jedinjenja, kao što je organska azo boja. Takođe, utvrđen je i potencijal fotolize vodonik-peroksida za obezbojavanjem sintetičkog rastvora date boje. Prva faza imala je za cilj sintezu materijala primenom različitih metoda pripreme i<br />konstrukciju solarnog paraboličnog reaktora, koji će se koristiti u Fenton i foto-Fenton procesima degradacije boje Reactive Red 120. Druga faza je podrazumevala karakterizaciju novosintetisanih materijala i optimizaciju procesa fotokatalize primenom Fenton i foto-Fenton procesa i određivanje postignutih efikasnosti primenjenih procesa. Takođe, vršeno je određivanje stepena mineralizacije i identifikacija degradacionih produkata nakon procesa degradacije tekstilne boje Reactive Red 120, kao i primena foto-Fenton procesa na realnom efluentu. Na osnovu dobijenih rezultata tokom primene Fenton procesa i korišćenjem oba tipa katalizatora u periodima niskog i visokog intenziteta zračenja, sa aspekta postizanja visoke efikasnosti obezbojavanja i najmanjeg izluživanja gvožđa,<br />može se zaključiti da je Fenton proces najefikasniji na pH vrednosti 3. AlFeB je pokazao veću reaktivnost čak i pri manje upotrebljenim dozama od0,05 g u odnosu na CuOFeB (0,2 g), kao i mogućnost manje upotrebe vodonik-peroksida od 2,5 mM, za postizanje visoke efikasnosti obezbojavanja i postignut visok stepen mineralizacije. Viši intenzitet sunčevog zračenja omogućava odvijanje reakcije obezbojavanja na višim pH vrednostima primenom oba katalizatora tokom fotoFenton procesa. Ovo je posebno izraženo kod CuOFeB tokom letnjeg perioda (pH 7), čak i pri nižim dozama katalizatora. Međutim, najveći udeo u procesu obezbojavanja pri upotrebi CuOFeB katalizatora ima fotoliza vodonik-peroksida (80%). Suprotno ovim rezultatima, pri istim reakcionim uslovima, potrebna je veća količina AlFeB katalizatora (0,1 g) i niža pH vrednost reakcije, a efikasnost procesa značajno zavisi od početne koncentracije H<sub> 2</sub>O<sub>2</sub>. Činjenica da se u pripremi katalizatora koristio bentonit kao prirodan, širokorasprostranjen i jeftin materijal i solarno zračenje kao obnovljiv i alternativni izvor fotona, gore navedene rezultate bi trebalo uzeti u obzir prilikom analize troškova efikasnosti primenjenog procesa. Takođe, primena unapređenih procesa oksidacije se razmatra kao predlog za najbolju dostupnu tehniku kada je u pitanju tretman otpadne vode tekstilne industrije, dok se kao dodatne nove tehnike uzimaju u obzir foto-oksidacije i ispitivanje mogućnosti njihove primene u prečišćavanju otpadne vode u tercijarnom tretmanu na poluindustrijskim sistemima.<br /> </p> / <p>The aim of this study was to investigate the decolorization efficiency of Reactive Red 120 (RR120) synthetic solution using ferrioxalate (CuOFeB) and Al, Fe-bentonite (AlFeB) catalysts in Fenton and photo-Fenton process. So far, studies of the application of a solar-assisted heterogeneous Fenton process with various Fe loaded catalysts and with ferrioxalate complex have been published, but according to the author’s knowledge, their comparison in terms of efficacy of decolorization has not been performed, which was one of the focus of research in this paper. In addition, the potential of solar energy represents 16.7% of the total utilized potential of renewable energy sources in Serbia, while the average solar radiation in Serbia is about 40% higher than the European average, making it very interesting for application in this type of treatment. In order to optimize the use of solar radiation and to improve the photocatalytic performance of the process, parabolic concentrating reactor was used for the first time. As a significant segment of the wastewater treatment technique during the degradation of persistent compounds, such as organic azo dye, solar photocatalysis was studied. Also, the potential of photolysis of hydrogen peroxide for decolorization of the synthetic dye solution was determined. Aim of the first phase of the study was synthesizing materials by using different methods of preparation, and construction of a solar parabolic reactor, which will be used in Fenton andphoto-Fenton dye degradation processes. The second phase involved the characterization of newlysynthesized materials and the optimization of the photocatalytic process by applying Fenton and photo-Fonton processes, as well as the determination of achieved efficiency of the appliedprocesses. Also, the degree of mineralization and the identification of degradation products after applied processes were determined. Application of the photo-Fenton process on a real effluent was conducted as well. Based on the obtained results during Fenton process and using both types of catalysts in periods of low and high intensity of radiation, from the aspect of achieving high efficiency of decolorization and smallest iron leaching, it can be concluded that the Fenton process is most effective at pH 3. AlFeB showed greater reactivity even at less used doses of 0.05 g, compared to CuOFeB (0.2 g), and the possibility of using less hydrogen peroxide (2.5 mM), achieving high efficiency and a high degree of mineralization. Higher intensity of solar radiationallows the reaction to be carried out at higher pH values when using both catalysts during the photo-Fenton process. This is particularly pronounced largest part in the decolorization process using the CuOFeB catalyst has a photolysis of hydrogen peroxide (80%). Contrary to these results, under the same reaction conditions, a higher doses of AlFeB catalyst (0.1 g) is needed at lower pH value of the reaction, and the process efficiency is significantly dependent on the initial concentration of H <sub>2</sub>O<sub>2</sub>. The fact that in the preparation of the catalysts bentonite as a natural, abundant, inexpensive material was used and solar radiation as a renewable and alternative source of photons, the above results should be taken into account in the cost-effectiveness analysis of the applied process. Also, the application of advanced oxidation processes is considered as a proposal for the best available technique when it comes to the treatment of wastewater from the textile industry, while as additional new techniques, photooxidation is considered as a candidate and the possibility of their application in the treatment of wastewater in tertiary treatment on semi-industrial systems.</p>
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Modeling and Parametric Evaluation of a Solar Multistage Flash With Brine Mixing Desalination Plant Using a Novel Dual Tank SystemKaheal, Mohamed M. 11 August 2022 (has links)
No description available.
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Zero CO2 factory : Energikartläggning av industrier och ett exempel på hur noll utsläpp nås / Zero CO2 factory : An energy audit of industries and an example on how to reach zero emissionsWannemo, John January 2019 (has links)
Industrin står för 32% av den globala energianvändningen och majoriteten av industrins utsläpp sker vid förbränning av fossila bränslen för värmeanvändning. Hälften av industrins värmeanvändning uppskattas vara i temperaturer upp till 400 °C vilket är lämpligt för värme från solfångare.Klädesindustrin står för 10% av de globala växthusgasutsläppen och majoriteten av de utsläppen sker vid textilproduktion och flera av textilindustrins processer är i temperaturintervall som kan använda värme från solfångare likt Absolicons T160.Data från energianvändning hos textilfabriker har samlats in och beräkningar på energianvändning och utsläpp har gjorts för erhållna data. Solfångarnas energiberäkningar har gjorts med hjälp av simuleringar från Absolicon applikation Field Simulator. En 3-stegs plan gjordes för 2 stora textilfabriker i Indien som visar hur de skulle kunna eliminera sina utsläpp från energianvändning.Kartläggningen visar att textilindustrin till stor del använder fossila bränslen och de 5 största textilfabrikerna i denna rapport visar en energifördelning mellan värme och el på 85% respektive 15%. Utsläppen per producerad massa varor i kg för de 5 fabrikerna uppskattas vara i snitt 6,1 kgCO2e vilket motsvarar en förbränning av 2,1 kg brunkol.De två stora textilfabriker i Indien samlade utsläpp från energianvändning redovisas vara 686 ktCO2e. Värmeanvändningen i fabrikerna sänks i 3-stegsplanen med 17% och fossila bränslen ersätts med värme från solfångare och biomassa. För att täcka 68% av det nya värmebehovet med värme från solfångare så behövs det solfångarfält med en termisk effekt på cirka 400 MW och en yta på cirka 1,3 km2. De resterande 32% av värmebehovet ska komma från förbränning av cirka 100 000 ton biomassa per år.Industrin har möjlighet att sänka stora delar av sina utsläpp genom att ersätta fossila bränslen i värmeanvändningen med till exempel värme från solfångare och biomassa. För att täcka stora delar av värmeanvändningen med solfångarfält behövs lediga ytor runt om och på fabrikerna. Fossila bränslen har i dagsläget ett lågt pris i förhållande till dess utsläpp och tillämpning av globala utsläppsrätter eller skatter bör appliceras för att påskynda omställningen till utsläppsfri energi och lägre utsläpp. / The industry sector accounts for 32% of the global energy usage where the majority of the energy is being used as heat. Most of the heat is generated by burning fossil fuels which leads to heat use being the largest source of emissions in the sector. About half of energy used as in the industries are in temperatures up to 400 °C which is suitable for heat provided by solar collectors.The apparel industry accounts for 10% of the global carbon emissions and multiple of the industry processes used in textile production are in temperature ranges reachable with solar collectors such as Absolicons T160.Energy data was collected from textile factories and calculations of energy usage and emissions was made. The calculations for solar collectors was made with Absolicons web application Field Simulator. A 3-step plan was created to demonstrate how two textile factories in India could reach zero CO2 emissions.The analysis shows that the textile industry’s majority of energy is being used from fossil fuels to generate heat where the 5 largest factories in this report average energy is 85% as heat and 15% as electricity. The emissions per produced mass of goods in kg is an average of 6,1 kgCO2e at these 5 factories which is comparable to burning 2,1 kg of black coal.The two large textile factories combined emissions from energy usage is reported to be 686 ktCO2e. In the 3-step plan the heat usage is reduced by 17% and heat from fossil fuels are replaced by heat from solar collectors and biomass. To cover 68% of the new energy demand it would require solar fields with a total thermal capacity of about 400 MW and an area of 1,3 km2. The remaining 32% of heat demand would be covered by burning 100 000 tonne of biomass per year.The conclusion is that he industry sector has a huge potential of reducing their emissions by replacing fossil fuels for generating thermal energy by thermal energy from e.g. solar collectors or biomass. It will require available spaces close to or on top of the factories to be able cover large portions of the heat demand with solar collectors. The current prices of energy from fossil fuels is low compared to their emissions and a global carbon market or taxes should be applied to accelerate the change to clean energy and lower emissions.
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Improving the light yield and timing resolution of scintillator-based detectors for positron emission tomographyThalhammer, Christof 06 July 2015 (has links)
Positronen-Emissions-Tomographie (PET) ist eine funktionelle medizinische Bildgebungstechnik. Die Lichtausbeute und Zeitauflösung Szintillator basierter PET Detektoren wird von diversen optischen Prozessen begrenzt. Dazu gehört die Lichtauskopplung aus Medien mit hohem Brechungsindex sowie Sensitivitätsbegrenzungen der Photodetektoren. Diese Arbeit studiert mikro- und nano-optische Ansätze um diese Einschränkungen zu überwinden mit dem Ziel das Signal-Rausch Verhältnis sowie die Bildqualität zu verbessern. Dafür wird ein Lichtkonzentrator vorgeschlagen um die Sensitivität von Silizium Photomultipliern zu erhöhen sowie dünne Schichten photonischer Kristalle um die Lichtauskopplung aus Szintillatoren zu verbessern. Die Ansätze werden mit optischen Monte Carlo Simulationen studiert, wobei die Beugungseigenschaften phot. Kristalle hierbei durch eine neuartige kombinierte Methode berücksichtigt werden. Proben der phot. Kristalle und Lichtkonzentratoren wurden mit Fertigungsprozessen der Halbleitertechnologie hergestellt und mit Hilfe eines Goniometer Aufbaus charakterisiert. Die simulierten Eigenschaften konnten hiermit sehr gut experimentell reproduziert werden. Daraufhin wurden Simulationen durchgeführt um den Einfluss beider Konzepte auf die Charakteristika eines PET Detektors zu untersuchen. Diese sagen signifikante Verbesserungen der Lichtausbeute und Zeitauflösung voraus. Darüber hinaus zeigen sie, dass sich auch die Kombination beider Ansätze positiv auf die Detektoreigenschaften auswirken. Diese Ergebnisse wurden in Lichtkonzentrator-Experimenten mit einzelnen Szintillatoren bestätigt. Da die Herstellung phot. Kristalle eine große technologische Herausforderung darstellt, wurde eine neue Fertigungstechnik namens "direct nano imprinting" entwickelt. Dessen Machbarkeit wurde auf Glasswafern demonstriert. Die Arbeit endet mit einer Diskussion der Vor- und Nachteile von Lichtkonzentratoren und phot. Kristallen und deren Implikationen für zukünftige PET Systeme. / Positron emission tomography (PET) is a powerful medical imaging methodology to study functional processes. The light yield and coincident resolving time (CRT) of scintillator-based PET detectors are constrained by optical processes. These include light trapping in high refractive index media and incomplete light collection by photosensors. This work proposes the use of micro and nano optical devices to overcome these limitations with the ultimate goal to improve the signal-to-noise ratio and overall image quality of PET acquisitions. For this, a light concentrator (LC) to improve the light collection of silicon photomultipliers on the Geiger-cell level is studied. Further, two-dimensional photonic crystals (PhCs) are proposed to reduced light trapping in scintillators. The concepts are studied in detail using optical Monte Carlo simulations. To account for the diffractive properties of PhCs, a novel combined simulation approach is presented that integrates results of a Maxwell solver into a ray tracing algorithm. Samples of LCs and PhCs are fabricated with various semiconductor technologies and evaluated using a goniometer setup. A comparison between measured and simulated angular characteristics reveal very good agreement. Simulation studies of implementing LCs and PhCs into a PET detector module predict significant improvements of the light yield and CRT. Also, combining both concepts indicates no adverse effects but a rather a cumulative benefit for the detector performance. Concentrator experiments with individual scintillators confirm these simulation results. Realizing the challenges of transferring PhCs to scintillators, a novel fabrication method called direct nano imprinting is evaluated. The feasibility of this approach is demonstrated on glass wafers. The work concludes with a discussion of the benefits and drawbacks of LCs and PhCs and their implications for future PET systems.
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Estudo de um coletor solar, tipo tubo evacuado modificado, utilizando um concentrador cilíndrico parabólico (CPC) / Study of a modified evacuated tube solar collector using a compound parabolic concentrator (cpc)Avallone, Elson [UNESP] 30 October 2017 (has links)
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Previous issue date: 2017-10-30 / As alterações climáticas tem fomentado a busca por fontes renováveis de energia. Assim, novos coletores solares têm sido o foco de pesquisadores em todo o mundo para novos concentradores, novas configurações de instalação e o estudo da estratificação térmica para melhorar o desempenho do sistema de armazenamento térmico. O sistema proposto, ou seja, utilizando concentrador solar com tubo evacuado, proporciona linearidade e constância na sua eficiência em relação aos coletores de placas planas. A alteração proposta, ou seja, tubo com duas aberturas, uma para entrada do líquido frio e outra para saída do líquido aquecido, elimina a interface física entre a água quente na região voltada para o fluxo de calor solar e a água fria na região inferior do tubo. Essa alteração provoca redução na eficiência térmica, porém aumenta o volume de água aquecida por dia. O concentrador CPC mostrou-se um importante equipamento do sistema, uma vez que a os raios solares incidem em uma região longitudinal definida no tubo coletor solar, direcionado pela geometria do CPC. Com a utilização desse equipamento elimina-se a necessidade de espelhos com seguidores solares, tornando o sistema vulnerável a oscilações elétricas, encarecendo o projeto e consumindo energia elétrica. O desempenho do coletor é avaliado a partir de testes experimentais utilizando a Primeira Lei da Termodinâmica como análise da eficiência. Esses resultados são comparados aos conceitos teóricos descritos na literatura científica. O espaço anular evacuado do tubo também se mostrou um importante aliado na linearidade do coletor, reduzindo a resistência térmica do ar. A estratificação térmica é avaliada tanto pelo número de MIX (Primeira Lei da Termodinâmica) como pela proposta de um novo coeficiente de estratificação utilizando a exergia (Segunda Lei da Termodinâmica). Das seis configurações propostas para o sistema estudado, a mais viável foi obtida na configuração 3, ou seja, tubo evacuado com CPC. / Climate change has encouraged the search for renewable energy sources. Thus, new solar collectors have been the focus of researchers around the world with new hubs, new installation settings and the study of thermal stratification to improve the performance of the thermal storage system. The proposed system, ie using evacuated tube solar concentrator provides linearity and stability of efficiency compared to flat plate collectors. The proposed change, i.e. a tube with two openings, one for cold liquid inlet and the other for hot liquid outlet, eliminates the physical interface between the hot water in the region facing the solar heat flow and the cold water in the lower region of the tube. This change causes a reduction in thermal efficiency, however increases the volume of water heated per day. Two radiometers were also developed, one thermal and the other optical, and the thermal radiometer was chosen because it had a similar behavior to the solar collectors, thus reducing the cost of the experimental bench. The CPC concentrator proved to be important equipment, once the concentration of sunlight focus on a longitudinal region defined in the solar collector tube, directed by the CPC geometry. Using this equipment eliminates the need for mirrors with solar trackers, making the system vulnerable to electrical oscillations, making the project more expensive and consuming electricity. The collector performance is evaluated from experimental tests using the First Law of Thermodynamics as an efficiency analysis. These results are compared to the theoretical concepts described in the scientific literature. The annular evacuated space in the tube also proved to be an important ally in the linearity of the collector, reducing the thermal resistance of the air. Thermal stratification is evaluated both by the MIX number (First Law of Thermodynamics) and by the proposal of a new stratification coefficient using exergy (Second Law of Thermodynamics). Of the six configurations proposed the most efficient was obtained in the complete configuration, i.e. evacuated tube with CPC.
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Méthodes avancées d'évaluation des charges de vent sur les structures de concentrateurs solairesKaabia, Bassem January 2017 (has links)
L’énergie solaire photovoltaïque concentré (CPV) est une solution de remplacement prometteuse aux structures solaires conventionnelles. Ce type de structure modulable doit être optimisé afin d’être compétitif par rapport aux autres types de production d’énergie. Les forces de vent demeurent la première préoccupation dans la conception de la structure porteuse en acier d’un tel système. L’objectif principal de cette recherche est d’assembler des outils numériques et analytiques afin de prédire les caractéristiques de sa réponse dynamique sous charges de vent turbulent. La maîtrise de cette étape est essentielle afin d’étudier d’une façon plus générique des solutions d’optimisation de la structure support par rapport à sa réponse dynamique sous charges de vent. Pour ce faire, la méthodologie principale de cette étude est composée en trois parties : (i) étude expérimentale à grandeur nature de la réponse globale sous les conditions réelles du vent ; (ii) développement des modèles d’analyse numérique dans lesquels les caractéristiques de structures réelles et des
modèles de forces aérodynamiques adéquates sont prises en compte ; (iii) application des outils développés dans une étude paramétrique pour évaluer plusieurs solutions à partir de cas d’étude dans le contexte d’une conception préliminaire.
Cette thèse est présentée sous forme de deux articles qui ont été soumis dans des revues évaluées par des comités de lecture ainsi que d’un article soumis et présenté dans un congrès international qui démontrent les contributions de cette recherche pour améliorer les pratiques de calcul des charges de vent sur des structures de concentration solaire non conventionnelles. Ces articles sont présentés comme suit (a) Étude expérimentale à échelle réelle de la réponse d’un prototype de concentrateur solaire sous charges de vent. Ce premier article a permis la validation de calcul des coefficients de forces aérodynamiques statiques et la révision des hypothèses de l’application du code ASCE 7-10 pour prédire les forces maximales agissant sur la structure dans la direction du vent ; (b) l’analyse temporelle
de la réponse dynamique d’une structure de concentrateur solaire sous charges de
vent. Cette étude a montré que le modèle et la méthode d’analyse développés selon des hypothèses simplifiées permettaient de prédire correctement les caractéristiques statistiques de la réponse dynamique mesurée en cohérence avec la méthode spectrale stochastique ; (c) Étude des effets des configurations structurales et des paramètres de vent sur l’optimisation de structure solaires sous charges de vent. Cette étude paramétrique a mis en évidence l’importance de l’effet des paramètres structuraux et ceux définissant le vent sur l’optimisation de la conception structural pour ce type de structure. Des recommandations pour optimiser l’action dynamique dans une phase de conception préliminaire ont été proposées. Ce projet de recherche a démontré finalement l’importance d’étudier d’une façon juste et pratique la réponse dynamique sous charges de vent qui mène à résoudre des préoccupations d’optimisation liées à différents types de structures d’énergie solaire en adoptant des hypothèses pratiques pour les ingénieurs. / Abstract : Concentrated Solar Photovoltaic (CPV) is a promising alternative to conventional solar
structures. These solar traking structures need to be optimized to be competitive against
other types of energy production. Wind action is the main concern in the design of the
steel support structure of such movable system. The main purpose of this research is to
assemble advanced numerical and analytical tools that allows realistic dynamic study of
structures under wind loading. This help to study accurately optimized alternative in
term of selecting structural and wind site conditions parameters. The methodology of the
present study involves three main steps : (i) experimental full-scale study of the global
response under real life wind conditions ; (ii) numerical modeling that captures the characteristics
of the real structures and include the aerodynamic force models to conduct
time-domain dynamic analyses ; (iii) preliminary design application that include the study
of the effect of stuctural and wind parameters in optimizing the dynamic wind action and
consequently the steel support structure.
The thesis is presented as an ensemble of three articles written for refereed journals and a
conference that showcase the contributions of the present study to thoroughly understand
the wind load effect on these nonconventionnel structures. The articles presented are as
follow (a) full-scale measurement of the response of a CPV tracker structure prototype
under wind load. The results presented in this first article help design engineers to evaluate
the use of the aerodynamic force coefficients for calculating wind load on similar structures
and to apply properly the ASCE7-10 in evaluating the maximum design wind force using
the equivalent static approach ; (b) time-domain analysis of solar concentrator structure
under gust wind. This study showed that the developed time-domain model using simplified
hypothesis could successfully predict the statistical parameters of the measured
dynamic response in coherence with the stochastic spectral approach ; (c) effect of structure
configurations and wind characteristics on the design of solar concentrator support
structure under dynamic wind action. This parametric study highlighted the importance
of selecting structural and wind parameters in order to minimize the dynamic action and
the steel support structure. Recommendations for optimizing dynamic wind action in a
preliminary design phase were proposed. The present research project has shown the need
to study accurately wind response to solve optimization concerns related to different type
of solar system structures. In addition, this study proposes simplified methods that are
useful for practical engineers when there is the need to solve similar problems.
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Popis rozložení napětí v okolí ostrého vrubu / A study of the stress distribution near the sharp notch tipSvoboda, Petr January 2018 (has links)
The presented diploma thesis deals with the problem of determining the stress singularity exponent of the V-notch. This task can be divided into two parts. The first deals with the theoretical background, that means the basic relations of mechanics and the basic concepts of fracture mechanics. The second part deals with the elaboration of the Williams method and the creation of a program for calculating the stress singularity exponent.
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Datový koncentrátor / Data concentratorDvorský, Petr January 2021 (has links)
The topic of this thesis is the design and realization of a modular Data concentrator for various types of measurements in diverse conditions. The device conception, basic principles, design and functionality are described herein. Also, the lightweight protocol design for radio communication, standardized XML format for data storage and cloud usage are described. The electrical design of the device as well as the design of the printed circuit board was made using the Eagle Autodesk electronic design automation software (Eagle Autodesk EDA). The control software written in C/C++ for a target microcontroller (ESP32-WROOM-32) is based on a FreeRTOS platform and ESP-IDF framework. An IDE for managing this software is Visual Studio Code with PlatformIO extension. Selected and used Cloud Platform is ThingSpeak from Mathworks, which uses certain components from Matlab platform.
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