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Lubricant Gap Shape Optimization of the Hydrodynamic Thrust Bearing
Ochulo, Ikechi ; Vacula, Jiří (referee) ; Novotný, Pavel (advisor)
The objective of this Master's thesis is to find, using genetic algorithm (GA), an optimal profile for lubricating gap of a thrust bearing of a turbocharger. Compared to the analytical profile, the optimal profile is expected to have minimized friction for an equivalent load capacity. Friction minimization is one way to increase the efficiency of the thrust bearing; it reduces the friction losses in the bearing. An initial problem was given: a thrust bearing with Load capacity 1000 N, inner and outer radii of 30mm and 60mm respectively, rotor speed of 45000 rpm and angle of running surface of $0.5^0$. Lubricant properties were also provided for the initial problem: oil density of $ 840 kg/m^3$, dynamic viscosity $(\eta)$ of 0.01 Pa.s With this data, the numerical solution of the Reynolds equation was computed using MATLAB. To obtain more information, the minimum lubricating gap thickness was also computed using MATLAB. With this information, the shape of the analytical profile, and its characteristics were found. The analytical profile was then used a guide to create a general profile. The general profile thus obtained is then optimized using GA. The characteristics of the generated profile is then computed and compared to that of the analytical profile.
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Engineering design of the vehicle suspension rocker
Poláček, Vojtěch ; Ramík, Pavel (referee) ; Bradávka, Marek (advisor)
Diploma thesis deals with the design and stress analysis of the rocker suspension for an autocross car. The research describes some real cases of using suspension with pushrod and rocker in motorsport. Subsequently, the work deals with the design of the wheel bump/rebound limiting stops and bump/rebound measuring. The challenge is to design a component shape, size and select fit of a rocker with an emphasis on low weight whilst maintaining sufficient strength and rigidity. The design study include stress analysis which leads to optimize the final shape.
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Optimization of an Adapting Pipes
Svozil, Jan ; Drábková, Sylva (referee) ; Katolický, Jaroslav (referee) ; Štigler, Jaroslav (advisor)
Adapting pipes are a significant part of any pipe-line network and they are the sources of substantial hydraulic losses. They are designed for a manufacturing simplicity, regardless of flow. This paper concerns with lowering of hydraulic losses of adapting pipes by means of the shape optimization. Several methods of a mathematical optimization are tested and due to the complexity of the task and the need of the computational distribution among several computers, the gradient based algorithm is used. These methods loop together with a CFD software then automatically explore the design space. Several optimizations of diffusers with different opening angles, shape parameterizations and boundary conditions are made for the better insight on hydraulic losses. In three chapters there is description of development of parametric description of bend by means of Bezier surfaces. At the end optimum shape is found with hydraulic losses were decreased about 22%, which was not validated by experiment. In the final chapter is application of developed software on the shape optimization of Kaplan draft tube.
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Response surface method in connection with CFD for shape optimization
Pleva, František ; Štefan, David (referee) ; Rudolf, Pavel (advisor)
This thesis is focused on shape optimization of Venturi´s nozzle with optimization method called response surface method. The first part of this work is concerned with the description of this method as well as explaining the basic principle. Furthermore, there is an explanation of the application of this method in synchronicity with CFD and its operating algorithm. The second part of this thesis is then focused on simple example with plane wing and simplified optimization of Venturi´s nozzle in which this method was tested. In the third part there is described full multiparameter shape optimalization of the nozzle for two geometries.
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New Elements of Heat Transfer Efficiency Improvement in Systems and Units
Turek, Vojtěch ; Klemeš,, Jiří (referee) ; Odstrčil, Miloslav (referee) ; Jegla, Zdeněk (advisor)
Zvýšení efektivity výměny tepla vede k poklesu spotřeby energie, což se následně projeví sníženými provozními náklady, poklesem produkce emisí a potažmo také snížením dopadu na životní prostředí. Běžné způsoby zefektivňování přenosu tepla jako např. přidání žeber či vestaveb do trubek ovšem nemusí být vždy vhodné nebo proveditelné -- zvláště při rekuperaci tepla z proudů s vysokou zanášivostí. Jelikož intenzita přestupu tepla závisí i na charakteru proudění, distribuci toku a zanášení, které lze všechny výrazně ovlivnit tvarem jednotlivých součástí distribučního systému, bylo sestaveno několik zjednodušených modelů pro rychlou a dostatečně přesnou predikci distribuce a také aplikace pro tvarovou optimalizaci distribučních systémů využívající právě tyto modely. Přesnost jednoho z modelů byla dále zvýšena pomocí dat získaných analýzou 282 distribučních systémů v softwaru ANSYS FLUENT. Vytvořené aplikace pak lze využít během návrhu zařízení na výměnu tepla ke zvýšení jejich výkonu a spolehlivosti.
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Topology Optimization of the Hinge on Elastic Foundation
Beruashvili, Vasili ; Symonov, Volodymyr (referee) ; Löffelmann, František (advisor)
Tato diplomová práce se zabývá modifikací původního tvaru součásti za účelem co nejlepšího splnění provozních podmínek daného zatížení a omezujících podmínek v programech M.S.C. NASTRAN, M.S.C. PATRAN a FUSION 360. Součást je připevněna na ortotropní desce (sendvičovém panelu). Cílem této práce je zjištění efektu elastického podkladu na výsledky optimalizace. Součást bude optimalizována za použití různých cílových funkcí a omezení. Elastický podklad změní tuhost, což může změnit napěťový stav součásti. Únosnost původního a modifikovaného tvaru bude srovnána pomocí programu M.S.C NASTRAN/PATRAN. Po tvarové optimalizaci má být 3D model připravený pro výrobní proces, který bude cenově nejefektivnější.
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Modern trends in the design of frame machine
Holík, Štěpán ; Urbánek, Michal (referee) ; Zeizinger, Lukáš (advisor)
The bachelor's thesis deals with the issue of using modern methods of machine structures design, especially topological optimization. The first part describes the history of design, design methods in terms of approach to the technical problem and product development process. The second part discusses the various methods used in the design. The methods of topological optimization are compared and software solutions that enable topological optimization are described in detail. The fourth part deals with the dimensioning of components using topological optimization with a demonstration of important details on a specific example in Ansys Mechanical and MSC Apex Generative Design.
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Shape Optimization of the Machine Components due to Variability of Input Data
Sawadkosin, Paranee ; Jonák, Martin (referee) ; Novotný, Pavel (advisor)
The objective of this Master’s thesis is to find shape optimal design based on min- imizing friction force of thrust bearing by using genetic algorithm(GA) which is one of an optimization toolbox in Matlab. Reducing the friction force of thrust bearing is one way of making shaft to decreasing friction losses. With four parameters of thrust bearing geometry number of segments(m), angle of running surface(), segment inner radius(R0), and segment outer radius(R1) substitute in Reynolds’ equation. In order to know friction force, it is necessary to generate a connecting variable, oil film thickness(h0) from loading capacity(W ) and revolution per minute(rpm). Friction power loss, as well as weight func- tion conclude the final shape optimization of thrust bearing: m = 7, = 0.1, R0 = 15 mm, and R1 = 20 mm.
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Lubricant Gap Shape Optimization of the Hydrodynamic Thrust Bearing
Ochulo, Ikechi ; Vacula, Jiří (referee) ; Novotný, Pavel (advisor)
Cílem této diplomové práce je najít optimální profil mezery mazání pro turbodmychadlo. Cílem je minimalizovat tření, udržovat nosnost a nezvyšovat průtok maziva. Tato multiobjektivní optimalizace se provádí pomocí genetického algoritmu (GA) v MATLABu. Minimalizace třecí síly snižuje ztráty třecího výkonu turbodmychadla. Řešení Reynoldsovy rovnice je počítáno numericky pomocí MATLABu. Je zjištěna minimální tloušťka mazací mezery pro počáteční problém. Funkce spline se používá ke generování obecného profilu mazací mezery. Tento profil je poté optimalizován pomocí GA v MATLABu.
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Shape optimization of civil engineering structure
Kuzbová, Šárka ; Vlk, Zbyněk (referee) ; Hokeš, Filip (advisor)
The bachelor thesis is focused on shape optimization of a selected load-bearing structure. The calculation is carried out in RFEM 6. The desired goal is to achieve an optimum state where the structure has the lowest mass and at the same time satisfies the ultimate and serviceability limit state. The optimization procedure of the selected structure is focused on optimizing the position of the diagonals. The bachelor thesis also includes a study of the shape optimization of the simplified statically certain and uncertain structure.
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