|
|
Failure probability of the ceramics part using Weibull weakest link theory
Kovář, Jaroslav ; Návrat, Tomáš (referee) ; Fuis, Vladimír (advisor)
This thesis compares Weibull weakest link theory with inclusion of one and all three principal stresses. Principal stresses needed for this theory were calculated with finite element method. The informational research is in the introduction of this thesis. It includes ceramic materials, Weibull weakest link theory, Gaussian quadrature over spherical surface and ceramic head of hip joint endoprothesis. Theoretical part is used for next calculations of probability of failure. The probability of failure of ceramic rod loaded by four-point bending is calculated in first calculations. This task is solved as contact in the next step. Next part of this thesis is about selection of suitable method of numerical integration. This method will be used in the calculation with all three principal stresses. The results of calculation with all three principal stresses are compared with the results of the calculation which includes only first principal stress. Firstly, this is done for cylindrical body and then used on head of hip joint endoprothesis. In the last part of this thesis, probability of fracture of head hip joint endoprothesis with shape deviation of nominal conicity is calculated.
|
|
|
Stress-strain analysis of a sclerotic artery during angioplasty
Trtík, Adam ; Fuis, Vladimír (referee) ; Burša, Jiří (advisor)
This bachelor thesis focuses on an analytical calculation of maximum stress and deformation in arterial wall suffering from atherosclerosis during angioplasty and compares this value to the stress in wall of both healthy and sclerotic artery loaded by normal systolic pressure. Finally, the results are compared with corresponding model using the finite element method. In the theoretical part, the histology of arteries, their biomechanical properties and pathogenesis of atherosclerosis itself are briefly described.
|
|
|
Stress analysis of the total hip joint endoprosthesis head under oblique loading
Janovský, Martin ; Janíček, Přemysl (referee) ; Fuis, Vladimír (advisor)
This diploma thesis is concerned with the stress analysis of the total hip joint endoprosthesis ceramic head under oblique loading. Load was obtain from experimental in vivo measurement on three patients, whereas two of them was the same weight. As input variables were use contact forces, especially knee bend and standing on one leg. Furthermore they will be considered shape deflections from ideal cone, especially circle deviation, cone deviation and cone plus circle deviation together.
|
|
|
Stress-strain analysis of crane truss loaded by a force with varying position
Cabaj, Gabriel ; Fuis, Vladimír (referee) ; Vaverka, Jiří (advisor)
The bachelor thesis deals with the stress-strain analysis of the truss of a gantry crane. The theoretical part clarifies the basic concepts of statics, elasticity and strength. The concept of influence lines and its use for solving stress-strain analyses of structures with variable position of the loading force is further presented. The practical part deals with a model 2D example, specifically, the design of a cross section for a simplified model of a gantry crane, which is represented by the truss structure. The results for trusses with different degrees of static indeterminacy are compared. Subsequently, the analytical results are verified by the numerical solution in ANSYS software. In the last analysis, a 3D model of a gantry crane with realistic parameters from available sources is created. Finally, the stress-strain analysis of the gantry crane is performed considering the variable position of the loading force.
|
|
|
Stress-strain analysis of stadium lighting mast
Tokoš, Richard ; Kovář, Jaroslav (referee) ; Fuis, Vladimír (advisor)
The bachelor thesis contains an analysis of a steel structure that serves as lighting in a football stadium. The main goal is to create a bar system, the equation of static equilibrium and the deformation condition and I will analytically solve the stress and strain. Then I will create a model in ANSYS and calculate the stress and strain numerically. The bachelor thesis contains a comparison of the results of these methods.
|
|
|
Computational modelling of mechanical tests of animal cell
Orlová, Lucie ; Fuis, Vladimír (referee) ; Burša, Jiří (advisor)
Předkládaná diplomová práce se zabývá stavbou živých živočišných buněk a jejich odezvou na mechanické zatěžování. Zobecněným zaměřením práce je popis mechanického chování buňky nejenom ve fyziologickém, ale i v patologickém stavu. Výchozím předpokladem pro úspěšné řešení zadané úlohy je vysoce interdisciplinární přístup kombinující výpočtové přístupy mechaniky těles (v~tomto případě metodu konečných prvků) s lékařským výzkumem. Nejdůležitějším bodem při tvorbě výpočtového modelu, pomocí něhož je možné aproximovat chování živé buňky při zatížení, je zejména identifikace mechanicky významných komponent a~jejich materiálových parametrů. V tomto případě jsou jako mechanicky význačné identifikovány spojité součásti jádro, membrána a cytoplazma, které jsou nově propojeny s prvky diskrétními (mitochondriální sítí) v hybridním modelu, jehož platnost je ověřena pomocí experimentálních dat. Tento model slouží jako podklad k vyhodnocení míry vlivu mitochondrií na celkovou tuhost buňky.
|
|
|
Influence of essential parameters on the radial clearance and stress-strain states in ball bearings
Šperka, Václav ; Vrbka, Jan (referee) ; Fuis, Vladimír (advisor)
Master thesis is focused on the research of influence of selected substantial parameters on stress – strain states in the deep groove radial ball bearing. The influence of radial load is analyzed, such as the influence of size of the bearing and row of the bearing, also influence of radial clearance is quantified. Next, the influence of thermal distribution in the bearing is analyzed for different combinations of thermal distributions and radial clearances. Conclusions from analyses are then used in the last task – suggestion of radial clearance for customer – specified assembly. Problem is solved using the finite element method (FEM) in pre/post processor MSC.Patran and solver MSC.Marc. To make analyses faster the substantial parameters are implemented in the algorithm for automatic generation of the bearing calculation (batch file).The theme of this thesis was commissioned by ZKL - Research and development, a. s.
|
|
|
Stress-strain analysis of lower limb prosthetic
Musilová, Kateřina ; Fuis, Vladimír (referee) ; Návrat, Tomáš (advisor)
This master thesis deals with lower-limb prosthesis. The aim of the first part of this work is stress-strain analysis of trans-tibial prosthesis, which is understand without prosthetic socket and the foam prosthetic feet. Analysis is made using finite element method in ANSYS Workbench 12.0 software. For the purpose of setting up the computational model it is necessary to make few partial models. Model of geometry of the prosthesis is made in SolidWorks 2009. Based on the outputs of stress-strain analysis and the results evaluation, the critical component is chosen and this one is evaluated according to limite state for fatigue. The algorithm of evaluation of named component in the state of high cycle fatigue is discussed in the second part of this thesis.
|
|
| |
|
|
Stress-strain analysis of a bar systems using finite element method
Fodor, Ján ; Fuis, Vladimír (referee) ; Návrat, Tomáš (advisor)
The aim of this bachelors thesis is primarily programming of algorithm for solving bar systems (i.e. trusses) using finite element method. Programming language Python and his modules NumPy, SciPy and Matplotlib are used . The results thus obtained are verified in the program ANSYS . This work also gives a brief overview of commercial and freely accessible scientific software. Finite Element Method is a numerical method used for solving technical problems in mechanical engineering, structural engineering, electrical engineering and related fields.
|
guest ::
