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1
Anderle, Milan. "Vývoj modelu kalcinace pro ANSYS Fluent". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-367526.
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The aim of the diploma thesis was creating a decarbonisation model of lime, implementation the model into CFD tool ANSYS Fluent and to test the decarbonisation model in a model of a real reactor. The required model was based on assumptions for a Shrinking Core Model (SCM). The main objective of this work was the non-catalytic conversion of substances and the search for the most used mathematical models for calcination. The CFD calculation, the sensitivity analysis and the Fluente parametric study were used. Data on the composition of gas flow, temperature, pressure and mass flow of limestone particles were selected for input variables. The particle model called Multiple Surface Reactions (MSR), which is a standard part of Fluent, was used at first. Subsequently, a UDF which was based on the SCM assumptions was written in the programming language C. The results of the CFD calculation were compared with the experimental values from the dissertation. It has been found that the MSR is sufficiently precise for calculation purposes but neglects the internal diffusion of CO2 through the CaO layer which forms behind the reaction front during calcination. It was found that it is possible to solve the flow with ongoing calcination without the need to know the parameters of the Arrhenian equation if the UDF is used. The created UDF incorporates the influence of intraparticular CO2 diffusion on the overall reaction rate.
2
Drexler, Pavel. "CFD analýza proudění vzduchu pro různé typy průtokoměrů". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220888.
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There are some basic information about pressure sensors and flow in the first part of my diploma thesis. For example turbulent and laminar flow, construction of pressure sensors and basic information abaut Ansys and –Fluent. Main part of this thesis is focused on CFD simulation of pressure and velocity in the vicinity of pressure sensors. I confront this simulated values with measured values in final part of this thesis.
3
Vince, Tomáš. "CFD analýza tepelného zatížení trubkovnice". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443458.
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This diploma thesis focuses on the phenomena of multiphase flow in a steam generator as a one of probable causes of tubes and tubesheet weld cracking. In the first part of the work, a research was carried out focusing on the boiling and the phenomenon of two-phase flow in technical applications, its characteristics and properties. The thesis continuous with an overview of available numerical multiphase models in the ANSYS Fluent 2021 R1 and a research of previously published works focused on two-phase flow with the presence of boiling. The research is followed by a description of the particular boiler, which is part of the nitric acid production plant in the chemical company DUSLO, a.s., its operating conditions and a more detailed description of the issue that is being addressed in this thesis. The second part of the work continuous with a description of the computational model, including a description of the geometry of the model and used simplifications, the computational mesh and the description of boundary conditions. Important part is the description of calculation setting of steady-state and transient CFD simulations in ANSYS Fluent. Finally, the results of the two-phase flow calculation are presented and then discussed in the conclusions.
4
CARO, DIAZ FREDDY SANTIAGO. "ANALYSIS OF FLUID STRUCTURE-INTERACTION (FSI) PROBLEMS IN ANSYS". Thesis, Faculty of Engineering and Information Technologies. School of Aerospace, Mechanical & Mechatronic Engineering, 2015. https://hdl.handle.net/2123/30023.
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The Fluid-Structure Interaction problems occur in many natural phenomena and man-made engineering systems, this fact has promoted the research in this area. The research in this field of study is implementing two different methodologies. The first one is the use of commercial programs that have developed FSI capabilities such as Ansys or ADINA. The second methodology is the development of computational codes to solve specific problems of FSI analysis. This Project in particular focuses in the evaluation of Ansys-Fluent to perform FSI simulations. Two aeroelastic cases were simulated in Ansys, they were: the delta wing, and the Onera M6 wing. The delta wing simulation is subsonic and its structure is a simple flat plate made out of aluminum. The Onera M6 wing simulation is transonic and its structure has multiple components that are made out of an orthotropic material. The FSI simulations of the delta wing were validated through comparison with experimental data reported in literature. A turbulence analysis and a mesh independence analysis were carried out as well. The validation showed a limited capability to replicate the results that were obtained in the experiment. The FSI simulations of the Onera M6 wing were validated through comparison with a simulation that was carried out in Patran-Nastran. In addition, a computational fluid dynamics (CFD) simulation in steady state was performed in Ansys in order to establish the bases of the configuration that was implemented in the FSI simulations in Ansys. The validation showed that Ansys-Fluent is able to reproduce the results obtained in Patran-Nastran.
5
Jybrink, Anton. "Dynamic CFD Modelling of Deploying Fins During Transitional Ballistic". Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70758.
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The transition from inner to outer ballistics is a crucial part for the stability of the projectile. A projectile is mainly stabilized in two ways, with fins or by rotation. This work is limited to analyze a fin stabilized projectile. The launch of the projectile and the deployment of the fins are a quick process, therefore high forces and high temperatures will act the stability of the projectile. Due to these factors, it is hard to quantify experiments to analyze the stability of the projectile. To gain knowledge about how the forces will affect the path of the projectile during the launch and the deployment of its fins Computational Fluid Dynamics (CFD) can be a useful technique. In this work, a 2D methodology have been developed in Ansys Fluent to analyze the launch of a projectile and the deployment of the fins. A RANS model have been used in combination of dynamic mesh in order to handle the movement of the projectile. The projectile accelerates due to a pressure rise which have been initialized by a mass flow and energy curve as a source term. This work indicates that it is possible to predict the flow behavior and the forces influencing the projectile and the deploying fins. This work used a 2D model throughout the simulations and a 3D model is therefore needed to further compare and validate the simulation methodology.
6
LOPEZ, REBOLLAR BORIS MIGUEL 547458, i REBOLLAR BORIS MIGUEL LOPEZ. "Aplicación de cfd-ansys-fluent en el estudio hidrodinámico de tanques de recirculación empleados en acuacultura". Tesis de maestría, CENTRO INTERAMERICANO DE RECURSOS DEL AGUA - Universidad Autónoma del Estado de México, 2015. http://hdl.handle.net/20.500.11799/40428.
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Tesis que se presenta para obtener el grado de maestría en Ciencias del AguaLa Dinámica de Fluidos Computacional (CFD) tiene distintas aplicaciones en diversas áreas de la ingeniería, principalmente en la modelación de flujos, donde es utilizada para conocer las características de un flujo en movimiento y determinar las variables que intervienen en su comportamiento, de manera teórica pero económica y con resultados muy cercanos a la realidad. En acuacultura, la CFD es utilizada para visualizar y evaluar el comportamiento hidrodinámico de tanques de cultivo de peces, tomando en cuenta las condiciones de flujo para el sano desarrollo de los peces. Sin embargo, pocos trabajos analizan la eficiencia de remoción de sedimentos de forma natural, considerando el comportamiento del flujo dentro del tanque. En el presente trabajo, se analiza la hidrodinámica de un tanque de recirculación de agua empleado en acuacultura, aplicando simulación por computadora a través de técnicas CFD, demostrando la importancia de realizar simulaciones aplicando métodos numéricos, para la obtención de parámetros hidrodinámicos, principalmente, los campos de velocidad y turbulencia ante diversos escenarios de operación de un sedimentador tipo hidrociclón. Los resultados obtenidos demuestran que los principales factores que influyen en la hidrodinámica del tanque y del sedimentador son: la forma y distribución de rejillas del sedimentador, así como el diámetro del mismo. El efecto que producen dichas rejillas, son diversas variaciones en la distribución de velocidades del tanque y principalmente dentro del sedimentador, afectando las condiciones óptimas del flujo para la sedimentación de partículas y por ende la eficiencia en la remoción de sedimentos dentro del tanque. Con los resultados obtenidos mediante la aplicación de CFD fue posible relacionar la hidrodinámica del sedimentador con su diámetro y estructura de rejillas, logrando tener un flujo idóneo en el tanque para al sano desarrollo de los peces y un flujo con velocidad total máxima de 2 cm/s dentro del sedimentador, suficiente para lograr la sedimentación de partículas, y con ello generar un sistema con características de auto-limpieza.
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Moghimi, Ardekani Mohammad. "Optical thermal and economic optimisation of a linear Fresnel collector". Thesis, University of Pretoria, 2017. http://hdl.handle.net/2263/61313.
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Solar energy is one of a very few low-carbon energy technologies with the enormous potential to grow to a large scale. Currently, solar power is generated via the photovoltaic (PV) and concentrating solar power (CSP) technologies. The ability of CSPs to scale up renewable energy at the utility level, as well as to store energy for electrical power generation even under circumstances when the sun is not available (after sunset or on a cloudy day), makes this technology an attractive option for sustainable clean energy. The levelised electricity cost (LEC) of CSP with thermal storage was about 0.16-0.196 Euro/kWh in 2013 (Kost et al., 2013). However, lowering LEC and harvesting more solar energy from CSPs in future motivate researchers to work harder towards the optimisation of such plants. The situation tempts people and governments to invest more in this ultimate clean source of energy while shifting the energy consumption statistics of their societies from fossil fuels to solar energy.
Usually, researchers just concentrate on the optimisation of technical aspects of CSP plants (thermal and/or optical optimisation). However, the technical optimisation of a plant while disregarding economic goals cannot produce a fruitful design and in some cases may lead to an increase in the expenses of the plant, which could result in an increase in the generated electrical power price.
The study focused on a comprehensive optimisation of one of the main CSP technology types, the linear Fresnel collector (LFC). In the study, the entire LFC solar domain was considered in an optimisation process to maximise the harvested solar heat flux throughout an imaginary summer day (optical goal), and to minimise cavity receiver heat losses (thermal goal) as well as minimising the manufacturing cost of the plant (economic goal). To illustrate the optimisation process, an LFC was considered with 12 design parameters influencing three objectives, and a unique combination of the parameters was found, which optimised the performance. In this regard, different engineering tools and approaches were introduced in the study, e.g., for the calculation of thermal goals, Computational Fluid Dynamics (CFD) and view area approaches were suggested, and for tackling optical goals, CFD and Monte-Carlo based ray-tracing approaches were introduced. The applicability of the introduced methods for the optimisation process was discussed through case study simulations. The study showed that for the intensive optimisation process of an LFC plant, using the Monte Carlo-based ray-tracing as high fidelity approach for the optical optimisation objective, and view area as a low fidelity approach for the thermal optimisation objective, made more sense due to the saving in computational cost without sacrificing accuracy, in comparison with other combinations of the suggested approaches.
The study approaches can be developed for the optimisation of other CSP technologies after some modification and manipulation. The techniques provide alternative options for future researchers to choose the best approach in tackling the optimisation of a CSP plant regarding the nature of optimisation, computational cost and accuracy of the process.Thesis (PhD)--University of Pretoria, 2017.
Mechanical and Aeronautical Engineering
PhD
Unrestricted
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Sénéchal, Ulf. "Holzverbrennung in Kaminöfen mit Keramikfilter - experimentelle Untersuchungen und mathematische Modellierung". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-138497.
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Zur Verringerung von Schadstoffemissionen werden in Kaminöfen oft Keramikfilter integriert, die Staub und Ruß aus dem Abgas entfernen sollen. Die Filter beeinflussen jedoch die strömungsmechanischen, energetischen und chemischen Vorgänge im Feuerraum. Für die Auslegung und die praktische Anwendung der Filter ist die Kenntnis der Einflussgrößen und deren Umfang nötig.
Mit Hilfe von experimentellen und numerischen Untersuchungen wurden die Stoff- und Energietransportvorgänge von zwei Kaminöfen charakterisiert. Zur Bestimmung der Massenabnahme von Holzscheiten kam eine neue, praktisch leicht umsetzbare Methode, basierend auf einer Schockkühlung mit flüssigem Stickstoff, zum Einsatz. Parallel dazu wurde die Massenabnahme der Holzscheite mit Hilfe einer Online-Massenbestimmung mittels Waage aufgezeichnet und ein Verfahren zur Bestimmung der Abbrandkinetik entwickelt. Die Schwierigkeiten der messtechnischen Erfassung und Auswertung der instationären Vorgänge wurden dargestellt und diskutiert.
Für die zwei Kaminöfen sind numerische Simulationen mit der Software ANSYS CFX erstellt worden, die weitgehend auf realen Geometrien beruhen. Vergleichende null- und eindimensionale Simulationen mit unterschiedlichen Reaktionsmechanismen und gasförmigen Brennstoffen wurden realisiert und hinsichtlich ihrer Eignung für die Berechnung von Kaminöfen untersucht.
Nach erfolgter Validierung wurde ein parametrisches Simulationsmodell eines Kaminofens erstellt. Mit diesem wurde eine Parameterstudie zur Untersuchung der Veränderung der Zielgrößen Heizleistung, Kohlenmonoxid- und Rußkonzentration sowie Gesamt- und Sekundärluftmassenstrom in Abhängigkeit der Parameter durchgeführt.
9
Rogers, Charles. "Computational Fluid Dynamics Analysis of an Ideal Anguilliform Swimming Motion". ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1940.
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There is an ongoing interest in analyzing the flow characteristics of swimming fish. Biology has resulted in some very efficient motions and formulating these motions is of interest to engineers. One such theory was written by Dr. William Vorus and Dr. Brandon Taravella involving ideal efficiency. It is therefore interesting to test the calculations to see if it is possible to design a motion that can create thrust without necessarily creating vorticity. The computational fluid dynamics software of ANSYS Fluent was used to calculate the resulting flow field of the eel motion to compare with the theoretical values.
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González, Silva Germán. "Metodologia para aplicar LES ao craqueamento catalítico fluido em um reator riser industrial". [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266671.
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Orientador: Milton MoriTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
Made available in DSpace on 2018-08-21T06:39:27Z (GMT). No. of bitstreams: 1 GonzalezSilva_German_D.pdf: 4427269 bytes, checksum: bb45c122c3faad0613f060ad4cbd3b61 (MD5) Previous issue date: 2012
Resumo: O objetivo principal desta tese é propor uma metodologia para aplicar simulação de grandes escalas (LES) em uma unidade de craqueamento catalítico industrial. Para atingir este objetivo, iniciou-se propondo uma metodologia para a construção da malha, sendo uma malha quase-uniforme. As malhas propostas foram implementadas para minimizar o esforço computacional e procedimento para a refinação uniforme no domínio do sistema. Inicialmente, foi estudada a fluidodinâmica de um leito fluidizado gás-sólido na escala de laboratório sem reação química, utilizando Simulação de Grandes Escalas. Com base nos resultados numéricos obtidos a partir de resultados da escala de laboratório foi aplicado o modelo cinético de 4 lump em uma simulação CFD tridimensional para um reator industrial FCC, utilizando LES para a fase gasosa, e considerando o catalisador como uma fase contínua (Euleriana). Os pacotes de simulação utilizados foram Ansys ICEM versão 13 para a construção da malha e Ansys CFX versão 13 para o pós-processamento dos resultados. No pós-processamento dos resultados foi proposta uma metodologia para determinar as médias azimutais das variáveis em planos perpendiculares ao escoamento e finalmente foram validadas as simulações com dados reportados na literatura. As principais conclusões do trabalho foram que foi possível diminuir o tamanho da malha e o tempo de processamento. Notou-se também que, ao usar malhas com discretização quase-uniforme não foi necessário fazer um refinamento de malha elevado, nem refinar perto da parede para o sistema gás-sólido
Abstract: The main objective of this thesis is to propose a methodology in how to apply Large Eddy Simulation (LES) on a unit of catalytic cracking. In order to achieve this, it was proposed an alternative way of constructing the computational mesh, by using quasi-uniform meshes. The proposed meshes were implemented to minimize the computational effort and procedure for refining them in the entire domain of the system. Initially it was studied the fluid dynamics of a lab scale gas-solid system without chemical reaction, using Large Eddy Simulation. Based on the numerical results obtained from lab scale results it was implemented the 4 lump kinetic model in a three dimensional CFD simulation of an FCC industrial reactor, using LES for the gas phase and considering the catalyst as a continuous phase (Eulerian). The simulation packages used were Ansys ICEM, version 13 for mesh construction and Ansys CFX 13 for computation and post-processing of the results. In the data post-processing it was proposed a methodology for calculating average values of fluctuating variables between two circular sections in the azimuthal direction. The results were compared with data reported in literature. The main conclusions of the results showed that it was possible to decrease the mesh size and the computational time. It was also noticed that by using quasi-uniform discretization it was not necessary to make a high mesh refinement near the wall for a gas-solid system
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química
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Filip, Patrik. "CFD simulace proudění páry v neregulovaném odběru parní turbíny". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318771.
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Diploma thesis named CFD simulation of the steam flow in the unregulated extraction of the steam turbine is about an analysis of the balance piston impact on the area of the steam turbine, where the extraction is located. First part describes basic knowledge of the steam turbine in general. At the end of this chapter, there is a description of the solved steam turbine. Next chapter is about introduction to the CFD. Practical part deals with a construction of 3D models, meshing and setting of the boundary conditions in the program ANSYS CFX. The main part of this thesis summarizes the results of the CFD simulation and stipulates the temperature range on the extraction pipe. In conclusion, there is a recommendation how to determine design temperature of the extraction pipe influenced by the balance piston.
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Kapell, Jennie. "Analysis of the Inner Flow in the Wave Energy Converter WaveTube". Thesis, KTH, Tillämpad termodynamik och kylteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-102293.
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Wave energy technology is currently growing and gaining popularity. With around 100 separate technologies researched globally in over 25 countries wave energy are believed to soon be able to compete with other renewable sources such as wind energy. One of the new technologies is WaveTube; a wave energy converter currently under development and in need of technical verification. The basic idea of WaveTube is a partially submerged container with an enclosed fresh water volume. The kinetic energy of the ocean waves are transferred onto the floating container, creating an inner flow in the structure and electricity is generated as the fresh water flows through turbines. Previous small-scale model tests have confirmed the basic idea of WaveTube and an inherent continuation is visualizing and evaluating the inner flow using Computational Fluid Dynamics. A simplified 2D simulation where the WaveTube structure is subject to a pure sinusoidal, rotational motion was believed to be able to give useful information about the inner flow field. However, this Master Thesis project shows that a simulation using ANSYS Fluent of this case is not a successful approach. With inner moving parts a so called dynamic mesh was required, which updates the mesh as the boundaries move. In order for this method to be successful the mesh needs to be of high quality. However, for the complex geometry that WaveTube is no mesh was found to meet the requirements and the calculations using the Volume of Fluid method were not able to proceed.
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Koren, Dejan. "Computational Fluid Dynamics Unstructured Mesh Optimization for the Siemens 4th Generation DLE Burner". Thesis, KTH, Mekanik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-178034.
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Every computational fluid dynamics engineer deals with a never ending story – limitedcomputer resources. In computational fluid dynamics there is practically never enoughcomputer power. Limited computer resources lead to long calculation times which result inhigh costs and one of the main reasons is that large quantity of elements are needed in acomputational mesh in order to obtain accurate and reliable results.Although there exist established meshing approaches for the Siemens 4th generation DLEburner, mesh dependency has not been fully evaluated yet. The main goal of this work istherefore to better optimize accuracy versus cell count for this particular burner intended forsimulation of air/gas mixing where eddy-viscosity based turbulence models are employed.Ansys Fluent solver was used for all simulations in this work. For time effectivisationpurposes a 30° sector model of the burner was created and validated for the meshconvergence study. No steady state solutions were found for this case therefore timedependent simulations with time statistics sampling were employed. The mesh convergencestudy has shown that a coarse computational mesh in air casing of the burner does not affectflow conditions downstream where air/gas mixing process is taking place and that a majorpart of the combustion chamber is highly mesh independent. A large reduction of cell count inthose two parts is therefore allowed. On the other hand the RPL (Rich Pilot Lean) and thepilot burner turned out to be highly mesh density dependent. The RPL and the Pilot burnerneed to have significantly more refined mesh as it has been used so far with the establishedmeshing approaches. The mesh optimization has finally shown that at least as accurate resultsof air/gas mixing results may be obtained with 3x smaller cell count. Furthermore it has beenshown that significantly more accurate results may be obtained with 60% smaller cell count aswith the established meshing approaches.A short mesh study of the Siemens 3rd generation DLE burner in ignition stage of operationwas also performed in this work. This brief study has shown that the established meshingapproach for air/gas mixing purposes is sufficient for use with Ansys Fluent solver whilecertain differences were discovered when comparing the results obtained with Ansys Fluentagainst those obtained with Ansys CFX solver. Differences between Fluent and CFX solverwere briefly discussed in this work as identical simulation set up in both solvers producedslightly different results. Furthermore the obtained results suggest that Fluent solver is lessmesh dependent as CFX solver for this particular case.
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Vobejda, Radek. "Výpočtové modelování aerodynamického hluku způsobeného bočním zrcátkem automobilu". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-401556.
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The master’sthesis deals with numerical modelling of aerodynamic noisewhich arisesinside of the carcabin. In the first part ofthe thesis simplified model of geometry of the car and of the inside acoustic pressure arecreated. After that numerical analysis of created models of geometry are doneandvarious models of turbulenceare discussed. The results of these CFD simulationswhere then used for changing the model of geometry of the wing mirror. Outputs of these simulations were used for solving the numerical analysis of noise in the car cabin.
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Skoog, Pontus. "Fluidrörelse- och värmetransportsmodellering i götugn". Thesis, Linköping University, Applied Thermodynamics and Fluid Mechanics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-57902.
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The purpose of this thesis for Sapa Heat Transfer is to examine a furnace in which aluminium is pre-heated before hot rolling. The project is modeled in a computer environment in which the air flow in the furnace and the heat transfer to the aluminium solids are included. The computer environment and its governing equations, as well as boundary conditions and generalizations, are presented and explained.
The simulations are based on two models. The first model has an asymmetric solid placement, which is how it looks in today's ovens. It is validated against collected data. The second model has a symmetric solid placement, in which improvements are introduced and evaluated.
The results indicate that a symmetric positioning of metal solids in the oven is preferable in order to achieve a good airflow distribution. The use of plates has been proven useful for steering the air to critial areas and to get an even distribution of the airflow. Lastly the simulations indicate that an increased airflow can compensate the less optimal flow distribution that arises with asymmetric solid placements.
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Ekman, Petter. "A Sensitivity Study of Some Numerical and Geometrical Parameters Affecting Lift". Thesis, Linköpings universitet, Mekanisk värmeteori och strömningslära, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-124197.
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Volvo Car Corporation (VCC) uses Computational Fluid Dynamics (CFD) and wind tunnel during the aerodynamic development of new vehicles. In the past VCC main focus has been on the drag force correlation to the wind tunnel measurements but in recent years improved methods for lift force correlations has been highly wanted. Three objectives were considered in this study to improve the lift force correlation between the CFD simulations and wind tunnel measurements for geometrical configurations of the V60 and S60 models.Poor mesh resolution for the wall bounded flow existed for the VCC mesh method and therefore prisms layers were considered in this thesis to increase the mesh resolution inside the boundary layer.As slick tyres generally were used in the CFD simulations better geometrical correlation was wanted to be studied as it could improve the lift force correlation between CFD simulations and wind tunnel measurements. Therefore detailed tyres were considered in this study.As the coarsest surface mesh size was used for the underbody and the components inside the engine bay, where some of the highest flow velocities occurred, mesh refinements were investigated for engine bay and underbody in this study.The prisms layers improved the predicted behavior for the boundary layer as it captured the large velocity gradients more accurately. Due to this, the skin friction prediction was also improved. Different flow behavior around the front wheels and rear wake occurred due to earlier separation. The different flow field caused an improved correlation for the lift force but worsened correlation for the drag force due to increased pressure at the rear of the cars. However, the front lift force trend correlation for the considered configurations was improved with the prisms layer mesh method.The detailed tyres caused slight more disturbances for the underbody flow which caused more attached flow around the rear of the car hence lowered pressure. Earlier separation around the front wheels also occurred for the detailed tyre geometry as the disturbed flow around the wheels was increased. Slight improved correlation for the front and rear lift forces to the wind tunnel measurements could be seen with the detailed tyre compared to the slick tyre.The mesh refinements for the engine bay and underbody showed significant differences for the flow at the underbody which had significant impact on the flow at the rear wake for the V60 model. Minor differences could be seen for the aerodynamic forces for the baseline configuration for the V60 model while great differences occurred for the configurations affecting the underbody. Due to this significant improved correlation for the front and rear lift force trends were achieved for the underbody configurations with the refined engine bay and underbody mesh method.Conclusions could be drawn that the prisms layer caused earlier separation due to its increased mesh resolution for the wall bounded flow. However, finer mesh resolution was needed inside the boundary layer to ensure consistent separation behavior for both the considered models. Improved correlation for the front lift force could however be seen. The detailed tyre only had minor effects on the flow field and aerodynamic forces and therefore not so important to include for further studies. The refined engine bay and underbody caused significant improved lift force trend correlation to the wind tunnel measurements and should be considered for future studies. To improve the correlation between CFD simulations and wind tunnel measurements increased mesh resolution for the wall bounded flow should be considered to better capture the large velocity gradients close to the wall.
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Heinz, Pavel. "Vstupní recirkulace u odstředivého čerpadla". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-416449.
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This diploma thesis deals with the phenomenon appearing in hydrodynamic pumps at the sub-optimal flow rate. This phenomenon is inlet recirculation, which is an undesirable phenomenon in the suction of the pump. This recirculation causes cavitation, pressure pulsations and may cause clogging of the suction line. The main goal of the diploma thesis is CFD simulation for the recirculation mode, identification of the flow phenomena, and designs of possible measures to suppress inlet recirculation.
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Mačák, Martin. "Modelování magnetohydrodynamických jevů". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-377336.
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Theoretical part of this thesis is dedicated to the theoretical basis of electric conduction phenomena in fluids and method of calculation of magnetohydrodynamic phenomena. In the experimental part, computational modules have been developed to complement and augment the use of commercial simulation programs for simulation in the field of magnetohydrodynamics. On practical examples of mass spectrometer simulation, Einzel lens, electron movement and electric circuit breaker, the functionality of the computational models and the correctness of the obtained results were documented. Created computational modules can be used to design and optimize products using magnetohydrodynamic phenomena.
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Sjösten, William, i Victor Vadling. "CFD Simulations of Flow Characteristics of a Piano Key Weir Spillway". Thesis, Uppsala universitet, Elektricitetslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414861.
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Comprehensive rehabilitation projects of dam spillways are made in Sweden, due to stricter dam safety guidelines for their discharge capacity. The Piano Key Weir (PKW) is an innovative design which has proven effective through several renovation projects made in many countries including France. In this study we investigate the flow patterns around a prototype PKW, located in Escouloubre dam in southern France, with numerical simulations through three different flow cases in Ansys Fluent. A computational domain containing the PKW is created in the CAD software Ansys SpaceClaim for the simulations. Three polyhexcore meshes are further generated using Ansys Fluent Meshing. The three flow cases are then simulated with a Reynolds-averaged Navier-Stokes (RANS) model, coupled with realizable k-epsilon and volume of fluid models. Through an assessment of the discretization error between three meshes, a relative error of one percent is obtained for the discharge rate. The numerical results are qualitatively compared with results from previously conducted physical experiments on this PKW. The RANS model does not capture the water surface undulations (due to turbulence) around the PKW. The effects from under modelled surface undulations are alleviated by inserting an air vent to the PKW, which results in a flow behaviour in good agreement with the physical experiments. Through this alteration, water discharge rates are computed with a maximum discrepancy of five percent compared with the corresponding experimental values. A large eddy simulation should be conducted in the future, to bring further light on air exchange and water interaction phenomena present in the PKW flow pattern.
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Matteucci, Simona. "Numerical Modelling of a Flameless Combustor". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
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Flameless combustion can be adopted as a low-emission combustion regime in the aviation sector, which is one of the biggest contributors to NOx emissions and is expected to grow in the near future. Nevertheless, several issues must be solved before any practical applications. Effective design procedure must deal with either combustion or heat transfer phenomena occurring at extremely low—temperature conditions. To this aim, experimental and numerical analyses focused on the characterization of fuel/oxidant behaviour are strongly needed and represent an essential step for further development.
Besides, the complexity of the analysed technological system requires advanced tools for the definition of the chemical kinetics, for the burner designs and more in general for the definition of aviation equipment design. In this light, the thesis has been addressed to the study of flameless combustion mechanisms within a combustion chamber prototype developed in the Faculty of Aerospace Engineering at TU Delft. In particular, the temperature and species concentration fields have been analysed. The CFD tool which will be used is Ansys Fluent together with two detailed reaction mechanisms (KIBO and RDM19).
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Kent, Jason A. "Numerical and Experimental Analysis of a TurboPiston Pump". ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1189.
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The TurboPiston Pump was invented to make use of merits such as, high flow rates often seen in centrifugal pumps and high pressures associated with positive displacement pumps. The objective of this study is to manufacture a plastic model 12†TurboPiston Pump to demonstrate the working principle and a metal prototype for performance testing. In addition, this research includes the study of the discharge valve to estimate the valve closing time and fluid mass being recycled back into the cylinder through hand calculations. Furthermore, a transient simulation was performed in CFD using Fluent to provide a better estimate of what will happen in the actual pump while running. Additionally, an experimental rig was designed to investigate the performance of the first generation valve on the TurboPiston Pump known as the flapper valve. Means to improve the hydrodynamic performance of both valves have been identified for future study.
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Cancela, Rodriguez Eva Maria. "Optimization of CFRP components positioning inside the autoclave through CFD simulations". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
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Carbon fiber reinforced polymers (CFRP) show an excellent balance between thermomechanical properties and low density, leading them to be the material of choice in many applications. In the past years, the use of polymer matrix composites has significantly increased in the aerospace, automotive and naval sectors. Correspondingly, the requirements on high performance and quality keep increasing with the market demand. This generates a big concern on material properties along with the production of a large number of components, minimizing cycles’ time.
This document deals with the optimization of the distribution of composite components inside the autoclave obtaining therefore, the best configuration in order to achieve fair properties in all the elements in the shortest time possible. This study has been done along with the company Eligio Re Fraschini S.p.A., analyzing one of their autoclaves. The aim is to find the best configuration for a given repetitive production.
The optimization procedure that has been followed consisted in, for each of the three different productions considered, assess a set of models representing contrasting scenarios, in order to understand the flow behaviour and find the optimal distribution. The outcomes for the different locations are obtained through simulations performed with Ansys Fluent, a computational fluid dynamic (CFD) software; the ideal configuration is the one maximizing the heat transfer through all the components, in an homogeneous way.
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Nunes, Bonaventure R. "Numerical Loss Prediction of high Pressure Steam Turbine airfoils". Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/51742.
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Steam turbines are widely used in various industrial applications, primarily for power extraction. However, deviation for operating design conditions is a frequent occurrence for such machines, and therefore, understanding their performance at off design conditions is critical to ensure that the needs of the power demanding systems are met as well as ensuring safe operation of the steam turbines. In this thesis, the aerodynamic performance of three different turbine airfoil sections ( baseline, mid radius and tip profile) as a function of angle of incidence and exit Mach numbers, is numerically computed at 0.3 axial chords downstream of the trailing edge. It was found that the average loss coefficient was low, owing to the fact that the flow over the airfoils was well behaved. The loss coefficient also showed a slight decrease with exit Mach number for all three profiles. The mid radius and tip profiles showed near identical performance due to similarity in their geometries. It was also found out that the baseline profile showed a trend of substantial increase in losses at positive incidences, due to the development of an adverse pressure zone on the blade suction side surface. The mid radius profile showed high insensitivity to angle of incidence as well as low exit flow angle deviation in comparison to the baseline blade.Master of Science
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Brogren, Felix, i Peter Gustafsson. "VIBRATION ANALYSIS OF THE FLUE GAS FAN IN MÄLARENERGI’S UNIT 6 : Troubleshooting using CFD simulations in ANSYS to locate the origin of the vibration spikes and suggest solutions for a more optimized performance". Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-40030.
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The purpose of this study is to investigate the flue gas fan in Mälarenergi’s Unit 6 and try to find what is causing the vibrations increase. The Fast Fourier transform (FFT) method was used for this degree project. A comparison was made with previous studies using FFT in order to pinpoint the source of the problem with vibrations. After a possible source had been identified, a computational fluid dynamics (CFD) simulation was performed using ANSYS to visualize the problem. Two cases were simulated using two different turbulence models: the K-epsilon model and the Large-eddy simulation (LES) model. The result from the CFD simulations was compared with previous studies that used similar turbulence models. The flue gas fan’s high vibrations are most likely flow-induced. The simulation result indicates that LES model performed better than the Kepsilon model. The lack of validation in this degree work means that it is hard to know the accuracy of the model. Based on the simulation results the most promising solution seems to be inlet straighteners.Syftet med studien är att undersöka rökgasfläkten i Mälarenergis Unit 6 och att försöka hitta vad som orsakar vibrationsökningarna. Fast Fourier transform metoden har används i detta examensarbete. En jämförelse har gjorts med tidigare studier som använt FFT metoden för att kunna urskilja källan till vibrationsproblemet. Efter en rimlig källa hittades så utfördes en CFD-simulering i ANSYS för att visualisera problemet. Två fall simulerades med två olika turbulensmodeller: K-epsilon modellen och Largeeddy simulation modellen. Resultatet från CFD-simuleringarna jämfördes med tidigare studier som använt liknande metoder. Rökgasfläktens höga vibrationer är med störst sannolikhet flödesinducerad. Simuleringsresultatet indikerar att LES modellen utfördes bättre än Kepsilon modellen. Då det saknas en validering i form av flödesmätningar så är det svårt att säga hur lik modellen är med verkligheten. Baserat på resultatet från simuleringarna så verkar inloppsgaller vara den mest lovande lösningen.
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Kohont, Alexander, i Roger Can Isik. "TERMISKT SMARTA HANTERINGSSYSTEM FÖR LITIUMJONBATTERIER : Analys av litium-jonbatteriets termiska beteende". Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55065.
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Batteries play an important role in a sustainable future. As the development for better andsmarter batteries continues, new areas of use emerge boosting its demand. Controlling thetemperature of a battery cell is a vital objective to ensure its longevity and performance. Bothcooling and heating methods can be applied to keep the temperature within a certain rangedepending on its need. This study will review the technical aspects of lithium-ion batteries,observe the different thermal management systems and cooling methods, and lastly examinethe required cooling flow needed for a battery cell to prevent its temperature from rising tocritical levels during its discharge. Using CFD ANSYS Fluent as a simulation tool, the resultsshow that different charging rates, in terms of C-rate, require different rates of mass flow tocontrol the temperature. Simulating the cell with natural convection, the cell peaks at hightemperatures even at lower C-rates, reaching up to 36,4°C and 48,8°C for 1C and 2C,respectively. Applying the cooling method with a flow rate of 0,0077kg/s reduces thetemperature significantly, resulting in temperatures of 26,95°C and 31,27°C for 1C and 2C,respectively.
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Kácal, Jan. "Optimalizace klapek pro letouny SKYLEADER". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-319260.
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This diploma thesis focuses on optimization of the flap for the ultralight aircraft Skyleader JA 600, which is produced by the Jihlavan s.r.o. company. Individual types of flaps used in ultralight aircrafts are described in the initial phase of the thesis. In addition, description of the plane of interest Skyleader has been conducted, while along with the basic characteristics the focus is mainly on its wing and flap. The thesis continues with detailed CFD method calibration task, which is mostly focused on the basic turbulent models comparison. The optimization task conducted within this diploma thesis includes CFD calculations to determine aerodynamic characteristics of the flap provided by Jihlavan company, and subsequent determination of its optimal position. An important part of this thesis is also evaluation of the load and strength of the flap in previously determined optimal position. At the end, the strength and fly tests of the flap in the new position are described.
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Succi, Martino. "Analysis of the efficiency of air and steam-assisted flares on offshore platform". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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Gas Flaring is nowadays uniquely recognized as a major environmental threat. In addition to that, it has been estimated that flaring operations are one potential under-reported or non-reported pollutants source.
Studying a flaring process, characterizing its emissions, and evaluating key indicators, such as the destruction & removal efficiency (DRE) and/or the combustion efficiency (CE), may be extremely difficult primarily due to (1) Type of Industrial Plant & Composition of the Stream to be flared, (2) Operation Mode, (3) Flare Design, (4) Meteorological Conditions, and (5) Possible Flare Malfunctioning.
As a consequence of that, being able to correctly model a flaring process with the help of Computational Fluid Dynamics (CFD) could represent a valid alternative to expensive flare tests, since grab samplings or remote sensing are costly operations. Moreover, it is impossible to test during startup, shutdown, and maintenance periods.
This study makes use of one of the most popular CDF software in order to investigate the interaction between crosswind and fuel jet velocity and to determine the optimal amount of assist air/steam to be provided to maximize the combustion efficiency for a given flaring apparatus.
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Shindle, Bradley W. "Computational Investigations of Polymer Sheet Breakup for Optimization of Devolatilization Processes in Steam Contactors". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1509379799347531.
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Kolaja, Adam. "Výpočtové a experimentální modelování přímého chlazení statorového vinutí synchronního motoru vodou". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228302.
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This thesis deals with computing and experimental problems of direct water cooling of stator winding that is assigned in synchronous motors. A model with similar material characteristic to a real motor has been made for experiments. The computing results showed us the appropriate place for the cooling system. This place has been chosen due to maximum efficiency and cost of the cooling system. The experiments on the model showed us, if the computing results are credible.
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Woldu, Yared, i Anton Fritz. "Using CFD to analyze thermal and optical influence on a zero pressure balloon at floating condition". Thesis, Luleå tekniska universitet, Rymdteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-69620.
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The ability to control the trajectory and understanding the atmospheric effects on the flight performance of a scientific high altitude balloon has long been an aspiring ambition. This thesis work analyses the thermal and optical environments at float using the simulation software, ANSYS FLUENT. The objectives for this thesis were to evaluate how the solar angle, sunshine factor and the ground emissivity altered the altitude for the balloon during floating condition in Steady-state simulations. A transient simulation was conducted to evaluate the diurnal cycle effects on the altitude of the balloon. The understanding of how the parameters influence the altitude will make it possible to autonomously route the balloon to desired altitudes where you have a favorable wind direction. Performing steady-state simulations showcased the significance of certain parameters. Different solar angles greatly influenced the temperature gradient on the balloon and hence a larger lifting force acted on the balloon when the sun was at its highest point. Varying the cloudiness mostly affected the maximum temperature distribution and did not affect the minimum temperature distribution. The steady-state simulations also indicated a limited but noticeable dependence on the ground emissivity. From the transient simulations it was further enhanced how great of influence the solar angle have, which was illustrated by running diurnal cycles. It was also apparent that there are great differences depending on the seasons. For future applications, it would be of interest to investigate the effects caused by wind velocities in the steady-state case. A comparative analytic solution should be performed in order to validate the simulation results.
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Allen, Jeremy L. "The Effect of Baffle Arrangements on Flow Uniformity in a Manifold for a Unique Solid Oxide Fuel Cell Stack Design". Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1320851931.
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Boga, Gabriele. "Analisi aerodinamica preliminare di un veicolo alimentato ad energia solare". Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14285/.
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L’obiettivo di questo lavoro è lo studio della variazione dei carichi aerodinamici per piccole variazioni della geometria su un veicolo da competizione ad energia solare. Questa analisi si inserisce nell’ottimizzazione aerodinamica di dettaglio. Il veicolo oggetto di studio è Emilia IV, auto sviluppata dal team Unibo Onda Solare. L’attività si è svolta tramite lo studio di tre configurazioni ottenute inclinando la parte superiore del veicolo originale di +2° e di -2°. Per le simulazioni fluidodinamiche è stato utilizzato il codice di calcolo commerciale Ansys Fluent. Le simulazioni sono state condotte con una velocità del flusso indisturbato di 20 m/s e con un numero di Reynolds calcolato sulla lunghezza della vettura di 6 milioni. Per la modellazione della turbolenza è stato utilizzato il modello k-epsilon realizable. È stato considerato uno strato limite turbolento per tutta la lunghezza del veicolo. La validazione del modello utilizzato è stata effettuata sulla geometria originale di Emilia IV tramite dati ottenuti precedentemente da simulazioni condotte con codici di calcolo Open Source (Open Foam) da ricercatori della Facoltà di Ingegneria di Forlì. La validazione della mesh è stata effettuata tramite simulazioni con quattro griglie di calcolo con numero di elementi crescente per verificarne la convergenza. Il numero di elementi della mesh definitiva è di 8 milioni composta da celle tetraedriche e da celle prismatiche. Si è data particolare rilevanza al coefficiente di resistenza delle tre vetture. Il modello utilizzato ha fornito risultatati sufficientemente accurati al fine di questo lavoro. La geometria originale si è dimostrata essere la più efficiente in termini di resistenza aerodinamica.
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Ringe, Shivansh. "Designing of One Directional Wave Tank". Thesis, Uppsala universitet, Institutionen för elektroteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-423335.
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Uppsala University wants to make a wave tank which can be used for experiment and education purpose. The project's aim is to get design parameters required to make a wave tank, design the wave tank, to do analysis on wave parameters taken from results and analysis of material which can be used to construct it. This project is an extension of the project called Numerical Wave Tank Design in which a literature study on existing wave research facilities was done [1]. The data from this project is used to get the dimensions of the wave tank. A study on hydrodynamics and wave theory is done to understand flow motion and wave generation. Ansys Fluent is used for Computational Fluid Dynamics (CFD). The software is used to test the wave tank with different wave absorber and observe if a good quality wave with a minimal reflection can be generated in the wave tank of chosen dimensions. Four models were created for testing wave absorber of different shapes. The setup for all the models was kept the same for comparison purposes. Waves generated from CFD were later compared with the theoretical waves obtained from wave theory. The next part was to model the wave tank in Computer-Aided Design (CAD) software, SolidWorks. The stress and strain analysis was done on the walls and support beam of the wave tank to know if the structure can sustain the water when fully filled. After creating static simulation different scenarios were performed on the beam and stand of the wave tank. The design study on these parts was compared to see which case provides a more optimal solution. It was found out that wave absorber having an elevation of 18.4 degrees, i.e., 1:3 slope provides the highest wave height for the given parameter and dimensions of the wave tank. In wave analysis, it was seen that wave height is proportional to the stroke length, water depth is proportional to wave height and time period is inversely proportional to the wave height. Cast stainless steel is used in a wave tank as it is cheap, reliable and robust. It was found out that the support beam 0.015 m thick is enough, although it can be increased to 0.02 m. In the design study of the wave tank stand, it was found out that a leg distance of 0.78 m and a leg width of 0.06 m is sufficient to withstand the weight of the wave tank.
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Hamberg, Micaela, i Signe Dahlin. "Numerical Study on Hydrodynamic Characteristics of Flood Discharge Tunnel in Zipingpu Water Conservancy Project : Using RANS equations and the VOF model". Thesis, Uppsala universitet, Elektricitetslära, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387206.
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To avoid the large amount of damage that floods can cause, spillway tunnels are used to control water levels. To ensure the safety of water transportation through spillway tunnels, the behaviour of the water throughout the tunnel is important to know. Physical experiments are time consuming and expensive, hence CFD simulations are a profitable option for investigating the performance of the spillway tunnel. In this project, simulations of water flow in a spillway tunnel were executed. A three dimensional model of the spillway tunnel in Zipingpu Water Conservancy Project was created in the software ANSYS Gambit. A coarse, middle and fine mesh with both hexahedral- and tetrahedral elements were also created for the model in ANSYS Gambit. The meshes were imported to ANSYS Fluent where the simulations, and a convergence analysis were made. The water flow was set to be described by the Reynolds-Averaged Navier-Stokes model, using the pressure solver, k-epsilon model and the VOF model. Physical experiments had previously been performed, and the simulated results were compared to these, in an attempt to find the parameters to replicate the experimental results to the greatest extent possible. The inlet velocity of the tunnel was known and the inlet boundary was set as a velocity inlet. The ceiling of the tunnel was set as a pressure inlet, the floor and walls were set as wall, and the outlet was set as pressure outlet. The simulated results showed similar behavior as the experimental results, but all differed from the experimental results. The grid convergence index, estimating the results' dependency on the mesh was 6.044 %. The flow was analyzed, and where the flow had unfavorable characteristics, such as a high cavitation number, the geometry of the spillway was altered in ANSYS Gambit to investigate if an improved geometry for the spillway tunnel could be found. The water flow in the revised geometry was simulated in ANSYS Fluent, and results showing flow with lower cavitation numbers was found.
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Šimberský, Michal. "Simulace proudění vzduchu a stanovení trvalé tlakové ztráty pro normalizovanou clonu". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220891.
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This master’s thesis deals with the simulation of flow through the normalized orifice plate. There is described flow measurement with flowmeters, which reduces the cross-section of the pipe and causes the pressure difference before and after the flowmeter. Following is a description methods of modeling of turbulent flow and a description of software for the simulation of flow from the company Ansys. The theoretical part is followed a practical part, which is focused on determining the permanent pressure loss caused by the orifice plate and the verification of straight pipeline lengths between orifice and obstacle.
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Dohnal, Miloslav. "Výpočtová analýza proudění v bubnové sušičce prádla". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231275.
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The aim of this work is to create a computational model of radial industrial tumble dryers, to calculate and identify the amount of air that flows through the inside of the drum itself. The calculation will be performed via computational fluid dynamics (CFD). Furthermore, compile transient balance model of mentioned dryers. Perform simulation balance model and compare the results of simulations with experimental measurements. By comparing the experimental data and simulation to determine the degrees of freedom of balance model and evaluate their impact on the assembled transient model. For a better understanding of the drying process, there is constructed a system of differential equations describing heat and moisture within the material being dried on a simple model. In the section devoted to the computational analysis of fluid flow is analyzed existing geometry of the drum, which has a major impact on the flow of air inside the drum itself. Following describes how to simplify its complex geometry entering the computational fluid dynamics. Then, there is carried out a simulation of fluid flow inside the tumble dryers using MRF and Sliding Mesh models. Finally, there is an analysis of the data obtained and determined the average amount of air flowing through the drum itself. On the contrary, the aim of the work is not to create another text tool for students engaged in CFD theme.
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Hladík, Petr. "Experimentální a výpočtové stanovení součinitelů přestupu tepla pro části průmyslové parní turbíny od firmy Siemens, s.r.o Odštěpný závod Industrial Turbomachinery". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231812.
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The subject of this diploma thesis is experimental and numerical assessment of the heat transfer coefficients during condensation of water steam in simplified parts of an industrial steam turbine. This simplified part is a pipe with circular cross section, which is often used in simulations of processes inside the steam turbine. The first part of thesis describes theoretical basics of heat transfer during conduction, convection and condensation. The content of other chapters is description of methods used to determine heat transfer coefficient. These are: ex-perimental analysis performed on a measuring device and evaluated using finite element ana-lysis (FEA), computational fluid dynamics analysis (CFD) in ANSYS CFX and analytical calculations of heat transfer coefficients using mathematical models for condensation. Thesis is concluded by validation and comparison of obtained results.
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Chinchore, Asmita C. "Computational Study of Savonius Wind Turbine". Cleveland State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=csu1389795972.
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Karlíková, Adéla. "Modelling of flow and pressure characteristics in the model of the human upper respiratory tract under varying conditions". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-413820.
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Cílem této diplomové práce je vytvořit 3D model horních dýchacích cest podle originálního modelu segmentovaného z CT dat, aplikovat různé podmínky na průtok vzduchu v modelu, a poté hodnotit změnu charakteristik rychlosti a tlaku. Model horních dýchacích cest byl vytvořen v prostředí softwaru ANSYS, který využívá výpočetní dynamiku tekutin, a byly použity Navier-Stokesovy rovnice pro modelování průtoku vzduchu v modelu. Nejprve byl vytvořen jednoduchý 2D model za účelem seznámení se s prostředím ANSYS. Dále byl zkonstruován 3D model horních dýchacích cest a byly modelovány charakteristiky rychlosti a tlaku za různých podmínek. Tyto podmínky zahrnují různé umístění a množství míst pro odběr vzorků v modelu a výběr různých kombinací vstupů. Nakonec byly prezentovány a hodnoceny výsledky spolu s ilustracemi modelů modelovaných za různých podmínek. 3D model lze považovat ze kompromis mezi výpočetní náročností a složitostí modelu a lze jej použít jako základ pro další výzkum.
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Horálek, Lukáš. "Výpočet chlazení asynchronního stroje pomocí programu Ansys CFX". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-318176.
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The issue this master’s thesis discusses the cooling synchronous machines. Specifically, the calculation of cooling induction motor using the finite volume method. Using Autodesk Inventor will create a 3D model of a real electric machine, ie asynchronous motor and then ANSYS WORKBENCH perform system analysis CFX, based on the finite volume method. Furthermore, we realize the air speed measurements on a particular machine and the individual results obtained by measuring and calculating the actual compared with each other. The master’s thesis also deals marginally with closely related to it. For the same machine model, we apply the calculation of the temperature fields using the finite volume method and them perform a thermal analysis. Next, we can carry out the measurement of the temperature on the motor itself and calculate the measured values and the measured compare each other.
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Fiala, Petr. "Tepelně-hydraulický a pevnostní výpočet výměníku tepla". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-228941.
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Main object of the work is stress analysis of specific parts of tube and shell heat exchanger by using MKP. Each part is judged by two different computation methods. The method based on computation values and the method nearing real condition of operation of device. To approach real load are in the work made basic heat transfer computations for entire device and for analyzed part are computed boundary conductance by using CFD.
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Acharya, Rutvika. "Investigation of Differences in Ansys Solvers CFX and Fluent". Thesis, KTH, Mekanik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-203937.
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This thesis aims at presenting Computational Fluid Dynamics studies conducted on an axisymmetric model of the Siemens SGT-800 burner using Ansys Fluent, Ansys CFX and Ansys ICEM. The goal is to perform a mesh study and turbulence model study for isothermal flow. The result will show the differences observed while using the two solvers by Ansys, Fluent and CFX. Two different meshes, A, coarse and B, optimal have been used for the mesh study. This will reveal the mesh dependency of the different parameters and if any differences are observed between the solver’s convergence and mesh independency performance. To further validate the mesh independency, a simplified test case is simulated for turbulent flow for 32 different cases testing the numerical algorithms and spatial discretization available in Ansys Fluent and finding the optimal method to achieve convergence and reliable results. Turbulence model study has been performed where k-ε, k-ω and k-ω Shear Stress Transport (SST) model have been simulated and the results between solvers and models are compared to see if the solvers’ way of handling the different models varies.Studies from this thesis suggest that both solvers implement the turbulence models differently. Out of the three models compared, k-ω SST is the model with least differences between solvers. The solution looks alike and therefore it could be suggested to use this model, whenever possible, for future studies when both solvers are used. For the models k-ε and k-ω significant differences were found between the two solvers when comparing velocity, pressure and turbulence kinetic energy. Different reasons for its occurrence are discussed in the thesis and also attempts have been made to rule out few of the reasons to narrow down the possible causes. One of the goals of the thesis was to also discuss the differences in user-interface and solver capabilities which have been presented in the conclusions and discussions section of the report. Questions that still remain unanswered after the thesis are why these differences are present between solvers and which of the solvers’ results are more reliable when these differences have been found.
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Goolcharan, John D. "Computational Fluid Dynamic analysis of Microbubble Drag Reduction Systems at High Reynolds Number". FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2542.
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Microbubble drag reduction (MBDR) is an effective method to improve the efficiency of fluid systems. MBDR is a field that has been extensively studied in the past, and experimental values of up to 80% to 90% drag reduction have been obtained. The effectiveness and simplicity of MBDR makes it a viable method for real world applications, particularly in naval applications where it can reduce the drag between the surface of ships and the surrounding water. A two dimensional single phase model was created in ANSYS Fluent to effectively model the behavior of bubble laden flow over a flat plate. This model was used to analyze the effectiveness of MBDR based on the following factors: Reynolds number, types of gas injected, upstream flow velocity, upstream fluid type, density ratio, flow rate of injected gas, using air as the upstream injected fluid.
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Plank, Jack R. "Nuclear Thermal Propulsion Cool-Down Phase Optimization Through Quasi-Steady Computational Analysis, and the Effect of Auxiliary Heat Removal Systems". The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1618934609976051.
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Wee, Hong Chuan. "Aerodynamic analysis of a canard missile configuration using ANSYS-CFX". Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/10707.
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Approved for public release, distribution unlimited--Cover.This study used the Computational Fluid Dynamics code, ANSYS-CFX to predict the static aerodynamic characteristics of a canard-wing missile configuration with a hemispherical nose, triangular wedge canards and fixed trapezoidal wings. The study was conducted for Mach numbers of 0.2, 0.8 and 1.2. The results were compared against experimental data from actual wind tunnel tests and data from a semi-empirical method, AP09. The ANSYS-CFX results showed good agreement for CN, CM, and CL but less agreement for CA when compared to the experimental results. The AP09 results also showed good agreement for CN, CM, and CL but also showed less agreement for CA.
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Steinbeck-Behrens, Cord. "ANSYS® AIMTM Produktsimulation für jeden Ingenieur". Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-206783.
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ANSYS ® AIMTM verbindet die Simulation mechanischer, strömungsmechanischer, thermischer und elektrischer Eigenschaften in einer neuen, intuitiven Oberfläche und einem über alle physikalischen Disziplinen gleichen Arbeitsprozess. Auf diese Weise kann die volle Breite physikalischer Fragestellungen nun auch direkt in der Produktentwicklung durch Konstrukteure und Entwicklungsingenieure genutzt werden, um ein ganzheitliches Produktverständnis zu erzielen. Wie dieser Zugang zur Produktsimulation für jeden Ingenieur mit ANSYS ® AIMTM erreicht wird, stellt der Vortrag unter folgenden Themenüberschriften heraus:
- Paradigmenwechsel in der Produktentwicklung
- Integriert Funktionen:
• Multiphysics Simulation
• Variantenanalysen
• Geometriemodellierung
• Prozessautomatisierung
- ANSYS® AIMTM live in der Anwendung
Das Produkt ANSYS® AIMTM ist seit Anfang 2015 als kommerzielles Produkt verfügbar. In den Versionen für Forschung und Lehre wird den Zugang mit der nächsten Softwareversion ermöglicht. Daher wird die Vorgehensweise in der Live Vorführung auch vielen langjährigen ANSYS ® Anwendenden neue Eindrücke geben. Im letzten Jahr wurde von CADFEM auf der SAXSIM Tagung ein allgemeiner Einblick in Möglichkeiten der gekoppelten Simulation mit ANSYS Workbench gegeben. Mittlerweile sind viele der dort genannten Anwendungsbeispiele einfacher in ANSYS ® AIMTM lösbar.
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Kloss, Tomáš. "Analýza působení větru na ocelové větrané opláštění". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265240.
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This master´s thesis analyzes an effect of wind load on the ventilated facade claddings. The analysis is performed on the various types of facades, from unventilated to ventilated facades with a different geometrical arrangement of facade shell. The theoretical part describes the basic knowledge about the theory of flow, turbulence modeling, determining an optimal domain, verification of the calculation model and user interface in the ANSYS software. The final part compares the value of the wind load reduction depending on the change of the gap widths and the size of ventilated spaces. The resulting values are obtained by CFD simulations. The thesis includes a design and an assessment of the steel hall construction.
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Orlandi, Francesco. "Applicazione e Confronto di Modelli Computazionali Turbolenti per l'Analisi dei Fenomeni Fluidodinamici in Camera di Reazione di una Sorgente di Plasma Termico di Tipo ICP-RF per la Produzione di Nanoparticelle". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Il presente studio è stato realizzato per operare un confronto, in ambito CFD, tra diversi modelli di turbolenza applicati a una geometria ridotta di torcia al plasma industriale di tipo ICP-RF, basato sul modello PL-35 di Tekna Inc. Lo studio è stato svolto all’interno del software FLUENT utilizzando delle UDF per caratterizzare le proprietà termofisiche del plasma. Il primo metodo utilizzato è un k-epsilon modificato secondo Bolot, dal quale, dopo aver validato i campi delle grandezze caratteristiche e l’attendibilità dei risultati sulla base di studi precedenti, si è ottenuto un campo simmetrico e ben delineato di turbolenza stazionaria. Il confronto con un k-epsilon standard ha chiarito il fondamentale apporto del termine sorgente aggiuntivo di Bolot per modellare correttamente la turbolenza e fornire il giusto campo di temperatura. Si sono poi utilizzati due metodi LES, WALE e Dinamico, e confrontati i risultati. La fiamma di plasma è risultata più verosimilmente realistica ma i campi di temperatura sono risultati troppo elevati nella regione a più alta temperatura, ovvero in ingresso in camera di reazione. I LES fino all’entrata in camera di reazione risultano concordi col modello k-epsilon ma successivamente la modellazione del fenomeno turbolento porta ad una elevata dissipazione di energia cinetica turbolenta che porta a valori del campo di temperatura troppo elevati. L’utilizzo invece del k-omega e del RSM, che hanno fornito campi completamente irrealistici, ha dimostrato l’inutilità di utilizzare tali metodi per sistemi simili data l’inadeguatezza dei suddetti modelli per tali sistemi. Il confronto dei modelli LES col k-epsilon rende necessario la modifica di tali modelli in un futuro per poter integrare gli effetti correttivi del termine sorgente di Bolot nel termine Cs di questi, in modo da poter unire la correttezza del modello k-epsilon con la risoluzione e il realismo tipico di questi modelli.
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Feilhauer, Michal. "Řešení dynamické odezvy vodohospodářských konstrukcí v interakci s kapalinou". Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-355595.
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Behaviour prediction of hydraulic steel structures with the view to surrounding influences in various design dispositions is a fundamental condition for operational reliability assessment of the analyzed construction. Reliable characteristics of construction behaviour defined by the specification of its movement within changes caused by time and environmental influences is of great importance. In currently used engineering mechanics formulation it concerns setting the response of the defined construction or its part to the given time variable mechanic load. Required response values, which are necessary for evaluation terminal dispositions of capacity and usability of the construction, are trans-location and tension, or values thence derived. Calculation is basic means for response prediction of construction. The thesis presented deals with complex multi-physical behaviour problems of water supply constructions in fluid structure interaction. There are presented various approaches to calculations of static and dynamic qualities of constructions. These approaches are divided into so called “direct method”, which is based on direct connection between two physical fields and the calculation is performed by the method of final elements, and so called “indirect method” , which is based on connection of two physical fields by means of various interfaces, which are described in this thesis. In case of indirect method, the calculation of running liquid is performed by the method of final volumes and the construction calculation is performed by the method of final elements. Within the scope of this thesis, static and dynamic responses of water supply constructions have been solved with the use of the above mentioned approaches. The results of the calculations in the scope of this thesis have been compared with the findings of performed experiments. The final part of the thesis describes the results and generalized findings gathered from the tasks by various approaches.
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Izadyar, Nima. "Identification and classification of key features of balconies to promote thermal comfort under natural ventilation mode". Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/206905/1/Nima_Izadyar_Thesis.pdf.
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Occupants of high-rise apartments often rely on mechanical air conditioning for cooling, impacting on greenhouse gas emissions and energy costs. This research investigated how balconies can reduce air conditioning use by increasing natural ventilation. Computational Fluid Dynamics was used to examine how balcony depth and the size of the balcony door impacts on air entering the apartment, and how that air moves around the apartment. It showed that a higher cooling effect was gained by reducing the door opening size and that shallow balconies result in non-uniform indoor air distribution. These results may lead to better building design and operation.