Spelling suggestions: "subject:"hydraulic""
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Integrated smart hydraulic displacement machine for closed systemsDöhla, Werner, Bauer, Jörg, Kemnitz, Rocco 26 June 2020 (has links)
The following article describes the development, validation and series introduction of a novel highly integrated smart electrohydraulic 4-quadrant displacement machine. Starting in 2012, an unique unit consisting of a hydraulic internal gear machine combined with a newly developed electric machine with integrated electronic unit was created. The developed unit aims at the application in fully active automotive chassis in combination with hydraulic shock absorbers. The very special requirements of this application resulted in a new development with numerous detailed solutions which are described below. Parallel and interacting with the product development, all new series assembly and testing devices tailored to this product was developed.
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Electro-hydraulic SWOT-analysis on electro-hydraulic drives in construction machineryInderelst, Martin, Prust, David, Siegmund, Michael 26 June 2020 (has links)
This paper discusses the potential of centralized or decentralized electro-hydraulic (EH)-drives in comparison to conventional hydraulic systems. The systems are presented in diagrams covering the major electric and hydraulic components for an exemplary application, but also include specific technical data like the sizing of the components according to power, pressure, rotational speeds etc. In a second step, all systems are compared and evaluated based on criteria like design effort, energy saving potential, controllability, and servicing and maintenance of the machine. The resulting effects on fuel consumption are summarized as well. Finally, an evaluation of the potential of EH-drives in construction machinery and a derivation of the demands for future customization of electro-hydraulic linear drives is given on the basis of a SWOT-analysis from the point of view of a construction machinery OEM.
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Análisis termohidráulico de la instalación ATLAS. Aplicaciones de la metodología de escaladoLorduy Alós, María 21 March 2022 (has links)
[ES] Ante el desafío que implica la reducción de los efectos del cambio climático, la industria nuclear se ha postulado como una buena alternativa para sustituir la producción de energía eléctrica a partir de combustibles fósiles. No obstante, debe constatar la seguridad de las centrales, para lo que resulta indispensable poder predecir su comportamiento ante escenarios operacionales y accidentales. A tal efecto, y dada la imposibilidad de disponer de datos de planta para analizar estos transitorios, se generan bases de datos en instalaciones a escala reducida a partir de experimentos, siendo necesarios métodos y estrategias de escalado que permitan extrapolar los comportamientos termohidráulicos.
Pese a la relevante contribución que suponen los experimentos al campo de la seguridad nuclear, en ocasiones se cuestiona la validez de sus resultados para reproducir el comportamiento de las centrales. Este hecho motiva la ejecución de test counterpart entre distintas instalaciones, que contribuyen a abordar la problemática del escalado, así como a demostrar la adecuación de los códigos termohidráulicos para predecir una respuesta realista de los sistemas.
La presente tesis doctoral explora la posibilidad de aumentar el número de experimentos counterpart a partir de la definición de nuevos escenarios y su simulación con el código termohidráulico TRACE5. Con este fin, se han desarrollado modelos de las instalaciones ATLAS y LSTF, y se han estudiado y simulado experimentos counterpart ya existentes entre dichas instalaciones. La identificación de los fenómenos termohidráulicos más significativos, y el análisis de su escalado y distorsión, configuran la base de conocimientos para abordar el diseño de los nuevos test. En la tesis, en particular, se plantea un escenario tipo station blackout para LSTF partiendo de las condiciones iniciales y de contorno de un test previo en ATLAS. La simulación del experimento confirma la idoneidad de ATLAS y LSTF para realizar experimentos counterpart, en los que la fenomenología relevante es similar, y pone de manifiesto algunas limitaciones de estas instalaciones en cuanto a la extrapolabilidad de ciertos fenómenos, debido a las distorsiones originadas por la diferencia de escala y tecnología. / [CA] Davant del desafiament que implica la reducció dels efectes del canvi climàtic, la indústria nuclear s'ha postulat com una bona alternativa per a substituir la producció d'energia elèctrica a partir de combustibles fòssils. No obstant això, ha de constatar la seguretat de les centrals, per al que resulta indispensable poder predir el seu comportament davant d'escenaris operacionals i accidentals. A aquest efecte, i donada la impossibilitat de disposar de dades de planta per a analitzar aquests transitoris, es generen bases de dades en instal·lacions a escala reduïda a partir d'experiments, sent necessaris mètodes i estratègies d'escalat que permeten extrapolar els comportaments termohidràulics.
Malgrat la rellevant contribució que suposen els experiments al camp de la seguretat nuclear, de vegades es qüestiona la validesa dels seus resultats per a reproduir el comportament de les centrals. Aquest fet motiva l'execució de test counterpart entre distintes instal·lacions, que contribuïxen a abordar la problemàtica de l'escalat, així com a demostrar l'adequació dels codis termohidràulics per a predir una resposta realista dels sistemes.
La present tesi doctoral explora la possibilitat d'augmentar el nombre d'experiments counterpart a partir de la definició de nous escenaris i la seua simulació amb el codi termohidràulic TRACE5. Amb aquest fi, s'han desenvolupat models de les instal·lacions ATLAS i LSTF, i s'han estudiat i simulat experiments counterpart ja existents entre les dites instal·lacions. La identificació dels fenòmens termohidràulics més significatius, i l'anàlisi del seu escalat i distorsió, configuren la base de coneixements per a abordar el disseny dels nous test. En la tesi, en particular, es planteja un escenari tipus station blackout per a LSTF partint de les condicions inicials i de contorn d'un test previ en ATLAS. La simulació de l'experiment confirma la idoneïtat d'ATLAS i LSTF per a realitzar experiments counterpart, en els que la fenomenologia rellevant és semblant, i posa de manifest algunes limitacions d'aquestes instal·lacions quant a l'extrapolabilitat de certs fenòmens, a causa de les distorsions originades per la diferència d'escala i tecnologia. / [EN] Faced with the challenge of reducing the effects of climate change, the nuclear industry has been postulated as a good alternative to replace the production of electricity from fossil fuels. However, it must verify the safety of the plants, for which it is essential to be able to predict their behavior in operational and accidental scenarios. To this end, and given the impossibility of having plant data to analyze these transients, databases are generated in reduced-scale facilities from experiments, being necessary scaling methods and strategies that allow the extrapolation of thermohydraulic behaviors.
Despite the relevant contribution that experiments make to the field of nuclear safety, the validity of their results to reproduce the behavior of plants is sometimes questioned. This fact motivates the execution of counterpart tests between different facilities, which contribute to addressing scaling issues, as well as to demonstrate the adequacy of the thermal-hydraulic codes to predict a realistic response of the systems.
This Ph.D. Thesis explores the possibility of increasing the number of counterpart experiments based on the definition of new scenarios and their simulation with the TRACE5 thermal-hydraulic code. In order to achieve this goal, models of the ATLAS and LSTF facilities have been developed, and counterpart experiments already existing between these facilities have been studied and simulated. The identification of the most significant thermal-hydraulic phenomena and the analysis of their scaling and distortion, configure the knowledge basis to approach the design of the new tests. In the Thesis, in particular, a station blackout scenario for LSTF based on the initial and boundary conditions of a previous test in ATLAS is proposed. The simulation of the experiment confirms the suitability of ATLAS and LSTF to perform counterpart experiments, in which the relevant phenomenology is similar. Moreover, it reveals some limitations of these facilities in terms of the extrapolability of certain phenomena, due to the distortions caused by the difference in scale and technology. / Lorduy Alós, M. (2022). Análisis termohidráulico de la instalación ATLAS. Aplicaciones de la metodología de escalado [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181700 / TESIS
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Thermal Hydraulics Simulations for Nuclear EnergyThunberg, Wilhelm January 2022 (has links)
No description available.
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Life Cycle Cost Analysis and Optimization of Wastewater Pumping SystemChen, Chao, Bhamare, Yogesh Vishwas January 2019 (has links)
Different attempts have been made to facilitate successful operation of Wastewater Pumping (WWP) system. The WWP units which are already existed in different parts of the world have been studied to identify its success, failure and different parameters associated with its suboptimal performance. The performance of WWP depends on three parameters namely pump, hydraulics, control system and pump station. These parameters are interdependent and must be carefully matched to achieve efficient WWP system. Nowadays the scenario has changed where organizations has started looking increasingly at the total cost of ownership, another way of saying Life Cycle Cost Analysis (LCCA) and recognizing the need to get most out of their equipment purchase. The master thesis includes theory part which describes the different parameters associated with WWP unit especially focusing on Xylems WWP system. This thesis is an attempt to help companies to know how LCCA could be productive management tool in order to minimize maintenance cost and maximize energy efficiency The study reported in this thesis work has been conducted to shed light over the use of Life Cycle Cost Analysis in WWP system. The current study tries to suggest and assess an adopted approach to ensure successful and efficient operation of WWP system with lowering energy demand and decrease in maintenance cost. Initial cost, Maintenance cost and Energy costs are important issues in the operation of WWP system since they are responsible for total cost over time. Therefore, description of each cost, formulas necessary for LCC calculations, data and survey structure, material and energy flow has been described. This work also aims to provide an extensive literature review, different survey and data collection techniques, analysis of collected data, statistical modelling, customer interaction by questionnaires and an interview with experts were used. LCC calculations were used to support the design and selection of most cost-efficient WWP system. Therefore, the given thesis work is an attempt to achieve better functional performance, improve existing design principles associated with WWP System, contribution to asses economic viability, support decision making to enhance operational quality to achieve efficient and successful WWP system.
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Two-phase CFD Modelling and Validation : SH204X Master Thesis Project Report / Tvåfas CFD-Modellering och Validering : SH204X MasterexamensarbetesrapportHärlin, Richard January 2022 (has links)
This project deals with two-phase CFD model validation, a subject which is currently under active research due to its complexity. The goal is to create a model that predicts data profiles to an acceptable degree for a wide array of flow conditions. The applications within the nuclear field would mainly be for safety analysis, e.g. to predict phenomena such as the critical heat flux. The underlying physics were investigated, and simulations were performed of two-phase flow of the coolant R12 using the program OpenFOAM in an attempt to match radial profiles of void fraction, interfacial area concentration, vapour velocity and sauter mean diameter for different flow conditions provided by the DEBORA experiments. The proper set of models was found via sensitivity testing: trying combinations of different models and model coefficients. The effect on the simulation result was investigated, with the models that improved the result kept while the rest were discarded. The main strategy was to find models that accurately predicted the sauter mean diameter, as initial sensitivity tests showed the result to be highly dependent on this parameter. The impact of initial conditions and mesh refinement was also investigated, and a temperature validation study was done. The process was aided by a number of Matlab programs written by the author, to calculate and verify inputs and to post-process the result. A model was found that simulated the subcooled nucleate boiling datasets to an acceptable degree. The model failed to accurately simulate saturated nucleate boiling. / Detta projekt behandlar tvåfas CFD-modellvalidering, ett ämne som fortfarande ärunder aktiv forskning på grund av sin komplexitet. Syftet är att utveckla en modellsom förutser dataprofiler till en acceptabel grad för en mängd olika flödesregimer.Inom kärnkraftsbranchen skulle detta primärt vara applicerbart inom reaktorsäkerhet,t.ex. för att förutse fenomen så som critical heat flux. Den underliggande fysikenundersöktes, och simuleringar genomfördes på tvåfas flöde av kylmedlet R12 med hjälpav programmet OpenFOAM i ett försök att matcha 14 dataprofiler för void fraction,interfacial area, vapour velocity och sauter mean diameter för olika flödesregimertillhandahålla av DEBORA-experimenten.Den rätta uppsättningen modeller fanns via känslighetsanalys, genom att testa olikakombinationer av modeller och modellkoefficienter. Deras effektersimuleringsresultatet undersöktes, och de modeller som förbättrade resultatet behölls,medans resten förkastades. Huvudstrategin var att hitta modeller som förutsåg sautermean diameter, bubblornas medeldiameter, väl, då preliminär känslighetsanalysvisade att resultaten var mycket känsliga på denna parameter. Inflytandet avinitialvillkor och mesh-förfining undersöktes, och en temperaturprofilsvalideringgenomfördes. Till hjälp i processern var ett antal Matlab-program skrivna avförfattaren för att beräkna och verifiera inmatning och behandla och visualiserautdatan. En modell hittades som simulerade underkyld kokning till en acceptabel grad.Modellen misslyckades med att träffsäkert simulera mättad kokning.
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Concept development of a compression molding machine for biocomposite materials / Konceptutveckling av en formpressningsmaskin för biokomposit materialPerttu, Gusten, Larsson, Adam January 2022 (has links)
The growing concern with the environmental impacts of disposable products has placed an emphasis on ensuring the sustainability of material systems. A shift in the selection of material can decrease the negative effects of disposable products. One class of materials with good credentials is biocomposite materials, a material partly consisting of biodegradable products. In this thesis project a compression molding machine suitable for the pressing of biocomposite materials are developed for the start-up Trash to Gold. The start up is in a early process of developing compression molding machine. As of now they use a modified workshop press to test out the pressing of to-go coffee cups made out of biodegradable a biocomposite material partly consisting of coffee grounds. The current press is not optimised for their expected customer group and it is therefore appropriate to develop a new one. The aim of this thesis project is to assist Trash to Gold in their development of a compression molding machine, suitable for upcycling biodegradable waste into disposable products. The objective of this thesis project is to develop a concept of a compression molding machine that can be used to print to-go coffee cups partly made of coffee grounds. The concept to be developed will be for a press that weighs less and has smaller dimensions than the current one to suit the target group. The product development methodology of the project is based on Ulrich and Eppinger’s book ”Product Design and Development”. Some of the approaches used from book are modified for better application on the project. The project also includes digital and theoretical tools to determine if the concept can withstand the pressure generated when the machine is in use. The result of the thesis project is a concept of a compression molding machine that meet requirements given by the start up. Suitable parts for the basic structure of the compression molding machine is presented such as how the pressing function will occur and the outer frame with where the different components will sit. The resulting concept is smaller and more light weight compared to the current machine. / Den växande oron för negativa effekter engångsprodukter har på miljön har lett till ett ökat intresse att säkerställa materialsystemens hållbarhet. En förändring av materialvalet fÅNor produkterna kan minska dessa negativa effekterna. En materialklass som hade kunnat minska de negativa effekterna är biokomposita material. Biokomposit material är ett material som delvis består av biologiskt nedbrytbara produkter. I detta examensarbete utvecklas en formpressningssmaskin anpassad för formpressning av biokomposita material. Projektet görs på uppdrag av startup-företaget Trash to Gold. Företaget håller på att utveckla en formpressningsmaskin och använder just nu en modifierad verkstadspress för att testa tillverkningen av engångskaffemuggar som delvis består av kaffesump. Den nuvarande pressen är inte anpassad för den förväntade kundgruppen och det är därför l'mpligt att utveckla en ny. Syftet bakom detta examensarbete är att hjälpa Trash to Gold att utveckla en formpressningsmaskin som är anpassad för återanvändningen av bionedbrytbara restprodukter till engångsartiklar. Målet med det här examensarbetet är att utveckla ett koncept av en formpressningsmaskin som kan användas för att formpressa engångskaffemuggar delvis bestående av kaffesump. Konceptet som tas fram ska vara för en press som väger mindre och har mindre dimensioner än den nuvarande för att passa målgruppen. Arbetets produktutvecklingsmetodik är baserad på Ulrich och Eppingers (U&E) bok ”Product design and Development”. Exempel på metoder som använts är identifiering av kundbehov, produktspekification, konceptgeneration, extern- och intern undersökning samt olika poängsättningsmetoder. Arbetet omfattar också teoretiska modeller och verktyg för att räkna på konceptets hållfasthet, materialval och val av komponenter. Resultatet av examensarbetet är ett koncept för en formpressningsmaskin som uppfyller de krav som ställts av start up-företaget. Lämpliga delar för grundkonstruktionen av formpressningsmaskinen presenteras. Till dessa hör vad som ska ge upphov till pressfunktionen samt den yttre ramen där de olika komponenterna kommer att sitta. Det resulterande konceptet väger mindre och har mindre dimensioner jämfört med den nuvarande maskinen.
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Spatial and Temporal Hydraulic Water Quality Models for Predicting Residential Building Water QualityMaria Arantxa Palmegiani (11798894) 07 December 2022 (has links)
<p>Significant seasonal changes in chemical and
microbiological water quality can occur in buildings at different fixture
locations due to temperature and time dependent reaction rates. Here, a series
of calibrated plumbing hydraulic-water quality models were developed for the
extensively monitored Retrofitted Net-zero Energy, Water & Waste (ReNEWW)
house in West Lafayette, Indiana USA. Knowledge gaps that inhibited higher
resolution water quality modeling were also identified. The eight new models
predict the absolute level of free chlorine, total trihalomethanes (TTHM), Cu (Copper),
Fe (Iron), Pb (lead), NO<sub>3</sub><sup> – </sup>(nitrate-nitrogen),
heterotrophic plate count (HPC), and <i>Legionella spp.</i> concentration at
each fixture for plumbing use, operational characteristics, and design layouts of
the plumbing system. Model development revealed that the carrying capacity to
describe Legionella spp. growth (and other organisms) under water usage and
plumbing design conditions is lacking in the literature. This information needed
for higher resolution modeling. Reducing building water use by 25% prompted
increased absolute concentrations of HPC and Legionella, each increasing by a
factor of about 10<sup>5</sup>. When the service line length was increased,
Legionella spp. concentrations increased by up to 10<sup>6 </sup>gene copies /L
in the Summer season. The proposed modeling framework can be used to support
better planning, design, analysis, and operational decision-making.</p>
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Design and Simulation of Digital Radial Piston Pumps Using Externally Actuated Cam SystemsKeith Scott Pate (13174803) 29 July 2022 (has links)
<p>Energy conservation is a growing topic of research within various fields. Digital Hydraulics is a division of fluid power that focuses on using on/off technology to improve the performance and efficiency of fluid power systems. One significant benefit of Digital Hydraulics is that it has enabled additional control over fluid power systems, which helps achieve component and system level improvements. Conventional radial and inline piston pumps use positive sealing valves, which mitigate leakage losses, compared to port plates commonly seen in variable displacement pumps. By using digitally controlled positive sealing valves on radial and inline piston pumps, leakage losses can be mitigated to develop a more efficient variable displacement pump. This work focuses on the design, modeling, and simulation of a mechanically actuated valving system developed for a commercially available radial piston pump. The design uses a ball screw actuation method to phase the cam during operation, changing the displacement. Using a modeling and simulation software, GT-SUITE, a simulation model was created for the digital pump that shows close correlation to the manufacturer’s data at high pressure. The parameters simulated, 50 – 200 bar, showed that the system could achieve a peak efficiency drop of approximately 11.0% from 87.0% to 76.0% from 100 – 25% displacement simulated at 200 bar and 500rpm. Compared to a typical variable displacement axial piston pump unit, the digital pump showed increased efficiencies across the bandwidth of 35-83% displacement, with a lower overall drop in efficiency across most of its operating conditions. In the comparison used, the pump is outside of its operating range and has not been optimized; thus, the simulation model created in this thesis will be used in the future to optimize the system and evaluate the system's potential performance and feasibility for future prototyping and testing as a proof of concept. </p>
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Modeling and Simulation for Power Loss Estimation in Electrified Drill RigsChit, Ali January 2024 (has links)
This master's thesis aims to establish a foundation for model-based engineering of drill rigs through the development, evaluation, and utilization of simulation models. Specifically, the project focused on creating a simulation model of the hydraulic tramming system in the SmartRoc D65 surface drill rig. The uncalibrated model was validated against physical tests conducted on the SmartRoc T35 drill rig, and the results provided accurate predictions with some room for improvement. The model sets a basis for identifying power losses and future potential optimization through electrification. A modeling methodology was developed to aid in the development of other simulation models representing a physical system. The thesis highlights the strengths and limitations of a quasi-static model when applied to dynamic systems. The findings suggest areas for future improvement and underscore the importance of continuous model refinement to enhance calculation accuracy.
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