|
|
Stress analysis of the total hip joint endoprosthesis head under ISO 7206-5 loading
Varga, Jozef ; Hlavoň, Pavel (referee) ; Fuis, Vladimír (advisor)
The aim of this work is to analyse axisymetric tasks by norm ISO 7206-5, which is used to determination of static strength of ceramic heads. In the numeric analysis there will be considered form variances from nominal conicalness and circularity of stem sections i.e. possible variances caused by production. Furthermore form changes of recess inside of the head measured on real samples will be considered. All these variances from nominal values are necessary to analyse in more details, because they can participate in destruction of ceramic heads. The stem system, ceramic head and load cone (DHK) will be simulated as a 2D axisymetric task and 3D quarter symetrical task. That is why is necessary to undertake also comparing analysis of 2D and 3D tasks and compare results or eventually evaluate the error. This problem is solved using of Finite element System ANSYS 11.0.
|
|
| |
|
|
Stress-strain analysis of internal plate fixator of distal radius fracture
Hussliková, Veronika ; Hájek, Petr (referee) ; Marcián, Petr (advisor)
Distal radius fractures are one of the most common fractures. In case of a complicated fracture, it is necessary to proceed with surgical treatment using an internal plate fixator. The aim of this thesis was to perform a stress-strain analysis of an internal plate fixator attached to the distal radius using bone screws. Computational modeling using finite element method was used to assess the mechanical interactions among the individual elements of this system. The stress-strain analysis was performed for three different types of fixation in geometry models including a distal radius fracture and a healed distal radius and for three different types of loads. In the evaluation of the results, the influence of the type of load and the influence of the healing of the bone tissue were assessed. For the bending load, which was the most critical, the yield strength was not exceeded in the plate or in the bone screws, and therefore irreversible plastic deformation of the material did not occur.
|
|
| |
|
|
Modelling of pressure equipment bolted flange connections
Kolátor, Matyáš ; Pernica, Marek (referee) ; Létal, Tomáš (advisor)
The bachelor thesis deals with computational modeling of flange connections. Due to its separability, bolted flange connections are a frequently used in piping systems or pressure vessels. For the right functionality of the connection, it is necessary to ensure the required tightness. In order to be able to describe the tightness, it is necessary to know the stresses and deformations in all parts of the connection. These days, standard calculation methods are at a high level of accuracy, on the other hand, in order to achieve this accuracy, they have to follow a lot of corrections, in which the original model based on the strength of material theory should be lost. The aim of bachelor thesis is to create computational models based on the strength of materials theory. Computational models are created to illustrate the application of strength of materials theory. At the end of the thesis, the results using several models will be summarized and compared.
|
|
|
Creating a computational model for stress-strain analysis of parts of generator
Sedláček, Radek ; Fučík, Karel (referee) ; Návrat, Tomáš (advisor)
This thesis focuses on creating of a computational model for stress-strain analysis of parts of a generator. Computational model is parametric and it allows use of various geometric variants of the shaft and rotor lamination. Parametric computational model in APLD language is compiled in the attached sheet of software MS Excel after entering input values. After solving in software ANSYS 14.5 are results imported into MS Excel sheet for further post processing.
|
|
|
Analysis of the use of 3D slicer SW for computational modeling in biomechanics
Kratochvílová, Hana ; Marcián, Petr (referee) ; Vosynek, Petr (advisor)
This thesis deals with a freeware program called 3D Slicer and its usefulness in the area of biomechanics. The introduction part describes the scope of the program and its functions. The next chapter shows a step-by-step modelling of a bone geometry using CT images and a comparison of geometries of bones created with different grayscale level using a program Gom Inspect. The last part focuses on importing geometries created in 3D Slicer, specifically femur and pelvis, into FEM platform ANSYS Workbench for preprocessing and defining femur’s stress and deformation characteristics.
|
|
|
Strain and stress analysis of the femur with distraction intramedullary nail
Konvalinka, Jan ; Marcián, Petr (referee) ; Florian, Zdeněk (advisor)
This master's thesis is focused on determination and analysis of stress and strain in femur with distraction intramedullary nail for treating leg length discrepancy with the method of distraction osteogenesis. Thesis is mainly focused on states after distraction when the callus consolidates. Problem of determining stress and strain is solved by computational modeling using FEM. Detailed description of modeling is included in this thesis, complicated 3D geometry of bone was acquired from segmentation of CT images. Computational model is solve with 4 different types of callus geometry and also material properties of callus are varied. The influence on stress and strain when the middle distal screw is not applied is also analyzed.
|
|
|
Influence of the surrounding tissue on the stresses in brain arterial aneurysms
Lipenský, Zdeněk ; Burša, Jiří (referee) ; Polzer, Stanislav (advisor)
This thesis is focused on stress in brain aneurysms. It consists of three parts. First part is aimed for gaining information about the topic from scientific resources. Next part consists of analyses of geometry of cerebral aneurysms on the computed wall stress. Analyses are performed on four basic geometrical models and results are being discussed. The risky areas in each investigated shape have been identified as well as the comparisons of stress between those shapes have been performed and the most dangerous shape among investigated shapes has been determined. Third part investigates the influence of surrounding tissue on the brain aneurysm. Conclusion of this thesis is that brain gray tissue has positive yet negligible effect on the computed wall stress.
|
|
|
Finite element modelling of pathological changes in human vocal folds tissue and their influence on videokymograph
Martínek, Tomáš ; Matug, Michal (referee) ; Švancara, Pavel (advisor)
Master´s thesis deals with creating planar computational model of human folds, involving fluid-structure interaction. With this model, the influence of changes in vocal folds tissue layers (stiffness, thickness) and their effects on the videokymograph image are studied. Analysis of the results also deals with the evaluation of pressure at selected points below, between and above the vocal folds. The results indicate a possible similarity with the behavior of human vocal folds with pathology. Background research of vocal folds function, an overview of vocal folds pathology and summary of computational models are included.
|
guest ::
