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Stress strain analysis of the femur based on the CT data collection
Nečas, David ; Marcián, Petr (referee) ; Vosynek, Petr (advisor)
The area of clinical biomechanics is a rapidly growing engineering discipline in the world of today. This master's thesis is concerned with the stress-strain analysis of human femoral neck. In the first place it emphasizes the creation of computational model, especially the model of bone material, because of its high level of inhomogeneity. The creation of the computational model has been tested using several software packages, which are often mentioned in connection with the biomechanical tasks. The latter part of the thesis contains finite element method analysis for several material models, which are based on extensive analysis of relations used to transfer the information from computed tomography data to material model properties. Subsequently, the realization of experimental measurement is described. The final part of the thesis contains evaluated results obtained from the FEM analysis, which are also compared with the experiment.
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Strength design of the aircraft spur
Profota, Martin ; Vosynek, Petr (referee) ; Vrbka, Jan (advisor)
This master thesis deals with computational stress-strain analysis of the tailskid of airplane L410 NG with main focus firstly the check current design of the tailskid and then the design another design solution with the able to absorb as much as possible the deformation energy. Solution of this problem is performed using computational modeling utilizing numerical simulation of quasi-static and crash deformation load of the tailskid with using explicit Finite Element Method (FEM) in program ABAQUS v6.14. After the introduction with problem situation and tailskid assembly introductory part is devoted to the research study of various designs of the tailskid for different types of airplanes. There follows these theoretical general principles of thin-walled structures and buckling of them. Before the creating of the computational model itself, the explicit form of the Finite Element Method is better described. The conclusion of this thesis deals with the mutual comparison of the most advantageous design variants of the tailskid and the selection of the most suitable one of them for the airplane L410 NG.
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Using free programs for topology optimization on selected problems in solid mechanics
Flídr, Ondřej ; Halabuk, Dávid (referee) ; Vosynek, Petr (advisor)
This bachelor thesis examines open-source software for topology optimization, analyzes their possibilities on selected problems of solid mechanics and verifies the results by the finite element method. The theoretical part describes the principles and methods by which the tasks of topology optimization can be solved. This is followed by search for open-source software using these methods. The calculation process in selected software is described in detail in solving sample tasks in the penultimate part. In the last chapter, the best open-source software are compared with each other and also with commercially distributed Ansys Workbench 19.2. The output is an evaluation of the usability of individual open-source software in industry. This thesis can also serve as a manual for using selected programs for inexperienced users.
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Comparative analysis of physiological, degenerative and postoperative lumbar spine using computational modeling
Krejbychová, Adéla ; Návrat, Tomáš (referee) ; Vosynek, Petr (advisor)
This diploma thesis deals with the comparative analysis of the physiological, degenerative and postoperative state of the lumbar spine. The problem was solved by computational modeling using the finite element method. For this solution, it was necessary to create appropriate computational models. The spine physiological state was compared with cases of the lumbar spine with different levels of spondylolisthesis, cases of the lumbar spine with different sacral angles, and cases of lumbar spine with applied fixators. Based on the performed analyses, it was found that spine degenerative state has a great influence on the distribution of stress in the vertebral discs and the vertebra itself. Compared to the physiological state, with increasing level of the spondylolisthesis the stress in the vertebral discs increases, while the stress in the vertebral section decreases. Furthermore, the spondylolisthesis affects the force flow. The higher the level of the spondylolisthesis, the more the force flow is shifted onto the posterior articular ligaments. The best results in terms of the spine physiological state were achieved with the applied fixator model.
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Study of MATLAB PDE toolbox usability in mechanics
Kováč, Patrik ; Vosynek, Petr (referee) ; Grepl, Robert (advisor)
This thesis deals with the practical usability of the PDE Toolbox in the MATLAB. It brieflydescribes the mathematical fundamentals of solution. The thesis presents the possibilitiesof PDE Toolbox in the creation of the model, geometry, boundary conditions, mesh and displayof results. The PDE Toolbox results from selected tasks from static, modal and transientmechanics and thermomechanics are compared with the analytical solution or with the FEMsimulation from the ANSYS. The main part deals with the evaluation and generalizationof results.
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Stress-strain analysis of the railway bridge in Zahrádky near Česká Lípa
Abdul moghni, Abdul rahman ; Vosynek, Petr (referee) ; Fuis, Vladimír (advisor)
Cílem této bakalářské práce je využití deformačně napěťové analýzy na Železniční most v Zahrádkách u České Lípy. Konstrukce mostu byla zjednodušena a vymodelována jako nosníková konstrukce. První část bakalářské práce byla věnována získávání vstupních dat a základních informacích z technické dokumentace mostu. V nosníkovém modelu bylo využito několik zjednodušení. První model považujeme za staticky neurčitý, zatímco druhý jako staticky určitou konstrukci. Každý model tedy obsahuje zátěž z důvodu vlastní váhy a zatížení způsobeno projíždějícím vlakem. Z důvodu objemnosti rovnic, využíváme k výpočtu software Maple. Zkontrolovali jsme i mezní stav vzpěru pro oba modely, avšak jsme uvažovali pouze zatížení vlastní váhou a zatížení způsobeno vlakem. Po získání analytických dat bylo důležité tyto výsledky ověřit. Toto bylo docíleno využitím metody konečných prvku za pomocí programu Ansys. Veškeré výpočty byly provedeny pro 2D modely. Jediná výjimka je numerická sekce, kde byl přidán 3D model za účelem porovnání s 2D modelem.
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Analysis of the effect of damping on the magnitude of the response during dynamic headlamp excitation
Lukáš, Jan ; Biskup, Martin (referee) ; Vosynek, Petr (advisor)
The aim of the submitted diploma thesis is the magnitude determination of the headlamp response to the dynamic excitation. Currently it is necessary to measure this response, because it is one of the assessed criteria of quality of the headlamp. When comparing results of the experimental measurement and the computational modelling, a good consensus of resonant frequencies is observed, but there are significant differences in acceleration amplitudes. The cause of this is the variable damping value. The theoretical part of the thesis deals with polymeric materials, basics of oscillation and damping. It serves to understand the mechanisms, which influence the results of the experimental measurement. The practical part is dedicated to the procedure of the computational modelling and the experimental measurement implementation. The analysis of the experimental measurement results leads to an ascertainment of nonlinearities, which influence the headlamp behaviour. The results of a sensitivity analysis of the computational modelling are used to create curves, on the basis of which the damping is estimated. The inclusion of the estimated damping into computational modelling leads to reduction of the compared differences of the acceleration amplitudes. The conclusion of the thesis contains the recommendation for the damping determination during the computational modelling of the headlamp.
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Using Salome Meca computing environment to solve problems of solid mechanics
Ptáček, Tomáš ; Vaculka, Miroslav (referee) ; Vosynek, Petr (advisor)
Given bachelors thesis deals with solutions of basic tasks of body mechanics with usage of the finite element method (FEM). An open-source software Salome Meca with Code_Aster solver is used there. Basic formulas of strength of materials on which is FEM based are introduces in the beginning. Then is presented software Salome Meca with its solver Code_Aster. Followed by own solution of tasks, which contain structural analysis and series of examples for solving the fracture mechanics. Numerical solutions from Salome Meca are compared with analytical solutions, if some exist, and with solutions from commercial software Ansys Workbench.
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Structure modeling of mechatronic systems with spot welds and their influence on the eigen frequency
Gajdík, Michal ; Hadaš, Zdeněk (referee) ; Vosynek, Petr (advisor)
This bachelor thesis examines various types of spot welds in Ansys Workbench 13. In first chapter of this thesis are described theoretical foundations of simulation modeling. In following phase are analyzed each methods of simulation modeling. Practical part is about realizing different types of spot welds and examining their impact on clamped boards. Outputs of this thesis are modal abilities of each executed type of spot weld. On attached CD are program annex and project in Ansys Workbench 13. The goal is to analyze differently modeled spot welds, displaying primal deflections and comparison of modal abilities.
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Using Calculix computing environment to solve problems of solid mechanics
Lukáš, Jan ; Lošák, Petr (referee) ; Vosynek, Petr (advisor)
Submitted bachelor thesis is focused on a solution of solid mechanics problems in a computing environment of the Calculix program. In the opening of the thesis there are briefly described theoretical foundations of finite element method. Subsequently there are analyzed particular parts of the program environment of Calculix. The main part of the thesis deals with solutions of three selected problems of solid mechanics. There are three different types of analyzes: static structural, modal dynamic and explicit dynamic. In the first assignment there is discovered deformation and stress in a fixed compressed squared timber. The second assignment deals with modal properties of the fixed squared timber. The last assignment discovers effect of loading velocity on the deformation of fixed compressed squared timber. In the conclusion there are briefly evaluated advantages and disadvantages of the Calculix program and there are compared solutions of the Calculix program and commercial program.
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