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Stress-strain analysis of aortic aneurysms
Man, Vojtěch ; Janíček, Přemysl (referee) ; Burša, Jiří (advisor)
This master thesis is focused on stress-strain analysis abdominal aortic aneurysm using ANSYS software. The model of abdominal aortic aneurysm are based on CT scans of five specific patients. The branching arteries are included to the model and one goal of this thesis is decision about their influence of the wall stress. In this thesis was used a hyperelastic materiál model, which is based on mechanical tests done on human arterial samples.
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Design of Device for Vehicle Center of Gravity Height Measurement
Rektořík, Jiří ; Vančura, Jan (referee) ; Hejtmánek, Petr (advisor)
The objective of this diploma thesis is the design of a device that measures the vehicle’s centre of gravity height position. The first part defines individual methods of measurement using various measuring equipment. The next part deals with the definition of requirements for the device and the definition of the design. A stress-strain analysis was executed for selected components. This diploma thesis describes the preparation process of the vehicle and the device for the measurement. The next part is dedicated to the design of the measuring chain and to the evaluation of the results. The thesis concludes with a theoretic analysis of the measurement inaccuracy.
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Biomechanical studies carpometacarpal (CMC) joint thumb
Podsedník, Karel ; Marcián, Petr (referee) ; Florian, Zdeněk (advisor)
This master thesis deals with stress-strain analysis of carpometacarpal (CMC) thumb joint. It is a preliminary study, which was not analysed on BUT Mechanical and biomechanical institute yet. There is a comparative stress-strain analysis of CMC with applied total endoprosthesis and physiological condition. The model of geometry was created based on CT images and processed with using software Catia and Solidworks. The problem was solved in numerical FEM (finite element method) in software Ansys 13.0
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Stress-strain analysis of tumorous total endoprosthesis of hip joint
Vystrk, Tomáš ; Konvalinka, Jan (referee) ; Marcián, Petr (advisor)
Tumorous total endoprosthesis of hip joint is used for reconstruction of the limb affected by bone tumor and to regain its functnion. Longterm load conditions must be considered by the reconstruction and the joint mobility must be enabled. Suitability of the endoprosthesis depends on its construction considering shape, material and with this related mechanical properties. This thesis deals with creation of computational model and stress-strain analysis of tumorous total endoprosthesis of hip joint. There are two different types of endoprosthesis modeled in this thesis, each with three different length of resected bone replacement. Based on stress-strain analysis an assessment of possible limit states is made.
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Pevnostní posouzení konstrukce výřezu dveří přetlakovatelného habitatu pro extrémní prostředí
Sláma, David ; Šálený, Vratislav (referee) ; Návrat, Tomáš (advisor)
Main goals of this master thesis are following: to perform the state of the art research of overpressure constructions (especially space habitats, plane fuselages); to create an own concept of the functional inside ending (hole) in the sandwich panel for a door; to perform stress-strain analysis of this concept; to perform the design optimalization of this concept in order to minimise the weight. To solve the problems above software Ansys 17.2 is chosen, because it allows to: model the material of the honeycomb core of sandwich panel as homogenous linear orthotropic material; evaluate reserve factors of all critical limit states; perform the design optimalization; perform Monte Carlo simulation. First and second design optimalizations discover, that with defined parameters: 0,635 mm width of aluminium sandwich face sheets and inner overpressure 0,1 MPa, a creation of the model, that would be safe by changing the values of design variables is not possible. Specifically, the maximum value of shear stress on the glued areas between aluminium face sheets and honeycomb core is higher than the shear strength of the glue. Therefore, two new concepts are created. First for inner pressure 0,03 MPa and bigger width of aluminium face sheets 3,175 mm, second for inner pressure 0,02 MPa and same width of aluminium face sheets 0,635 mm. For both these concepts, an overall reserve factor is calculated. First, the value of an overall reserve factor is calculated deterministically. Secondly, the value of an overall reserve factor is calculated stochastically considering the variance of material properties of the honeycomb core ± 10 % by Monte Carlo simulation. An overall reserve factor of the concept with inner pressure 0,02 MPa is determined as 1,21. An overall reserve factor of the concept with inner pressure 0,03 MPa is determined as 1,20. The weight of the concept for inner pressure 0,03 MPa is though 4 times bigger than the weight of the concept for inner pressure 0,02 MPa. In the concept for inner pressure 0,02 MPa the maximum value of HMH stress in aluminium components is critical, stochastically considered material properties of the honeycomb core don’t have a significant influence on this value. In the concept for inner pressure 0,03 MPa the value of maximum shear stress on the glued areas between aluminium face sheets and the honeycomb core is critical, stochastically considered material properties of the honeycomb core have a significant influence on this value. In the concept for inner pressure 0,03 MPa an absolute error of overall reserve factor is 8 % (overall reserve factor calculated deterministically was 1,28) which is significant. Monte Carlo simulation is also used to find that the value of Poisson ratio XY of the honeycomb core doesn’t have statistically significant influence on all limit states. Value of the reserve factor of the honeycomb core is higher than 2 in both concepts. Monte Carlo simulation discovers that this value can be significantly lower. Using Tsai-Wu failure criteria the reserve factor in the concept for inner pressure 0,02 MPa is determined as 2,72 deterministically x 2,41 stochastically (absolute error 31 %), in the concept for inner pressure 0,03 MPa the reserve factor is determined as 6,85 deterministically x 6,17 stochastically (absolute error 68 %).
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Stress-strain analysis of the solids with highly curved centerline
Peter, Ondřej ; Man, Vojtěch (referee) ; Novák, Kamil (advisor)
The bachelor thesis deals with stress-strain analysis of the solid with highly curved centerline. The thesis is divided into three main parts: background research, computation modelling and performing of the experiment. All analytical equations and practical examples were summarized in the first part of this thesis. In second part, computation model is solved by using analytical and numerical approach. Next, the analytical and numerical approaches are compared to each other. Third part deals with experiment.
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Stress - strain analysis of total hip replacement - type Santori
Huťka, Pavel ; Fuis, Vladimír (referee) ; Florian, Zdeněk (advisor)
Submitted Diploma thesis deals with stress-strain analysis of deformation proximal end of femur with applied total hip joint endoprosthesis (replacement) – shortcut type. To identify deformation and tensity (stress) was used computational simulation by method of final elements. Have been created two computational models TEP- type Santori and type DePuy Proxima. Geometry model Santori was created on low level model geometry through the use of X-ray photograph. Principle of geometry model type DePuy Proxima was real Femoral stem endoprosthesis which was scanned on scanner ATOS. Geometry of both these replacements were set up in program Rhinoceros 4.0 and then execute in program CatiaV5R17. Data for geometry model of femur were gained from CT chains. Material model of femur have been crated in two variants. The first one looks at structure bone tissues and the second one were created by Gruen´s zones. Femoral Stem was weighted by static equivalent resultant force acting in hip joint. Computational model of system and self solution, including depiction results, was done by ANSYS Workbench 11.0 for four model variants.
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Effect of location and orientation of dental implant on stress-strain states in mandibular bone
Thomková, Barbora ; Valášek, Jiří (referee) ; Marcián, Petr (advisor)
The master’s thesis deals with issues belonging to the field of dental biomechanics, specifically the mechanical interaction of dental implants with the bone tissue of the mandible. The thesis focuses on the stress-strain analysis of the mandible with the implant inserted in different positions, with a different angle relative to the occlusal plane. The solution is performed by computational modeling using the finite element method. The geometry model of mandible was created based on CT images. The aim of the master’s thesis was also to compare the influence of the choice of the material model of cancellous bone tissue on the resulting stress-strain states of the mandible with the dental implant. Three material models of cancellous bone tissue were created - two homogeneous material model and a heterogeneous material model, which was based on CT image data. The work also investigates the effect of rotation (+5° or -5°) of implants in basic positions on the resulting stress-strain states. The stress-strain analysis showed that position and rotation has a greater effect on the stress and strain of bone tissue and implant than the chosen material model of cancellous bone tissue.
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Stress - strain analysis of jaw with tooth implant type BOI
Marcián, Petr ; Fuis, Vladimír (referee) ; Florian, Zdeněk (advisor)
Submitted master thesis deals with stress - strain analysis of jaw, with dental implant. The implant serve as a suitable pillar for crown or dental bridge, when one or more teeth are lost. The project is oriented on BOI (basale - oseo - integrable) dental implant type, which is produced by DENTALIHDE company. Stress – strain condition of the mandible system with implant have been established by computational simulation, with use of the final elements method. Important part of down jowl is simulated on with EDS and EDDS applied types of implants. After implementation the implant begins to heal. Therefore the special attention is paid to stress - strain states on various level of osteointegration. There is a detail description of production of single part computational model and his solving in the master thesis. Presentation of large chapter with results and subsequent alteration stress - strain analysis is part of the master thesis. Program SolidWorks 2005 was used to create the geometric model. Computational model and the actual solving was accomplished with use of ANSYS 11.0 and ANSYS Wor-kbench systems.
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Stress-strain analysis of chosen pipe flange
Pařízek, Daniel ; Poduška, Jan (referee) ; Novák, Kamil (advisor)
The bachelor's thesis deals with stress-strain analysis of chosen type of pipe-flange. The chosen type was a Weld-Neck flange, normalized according to European standard EN 1092-1+A1. Initially, the pipe-flange is modelled as a composed solid body, using available analytical theories of thin-walled axisymmetric shells and plates. Then, the stress-strain analysis is performed using FEM software Ansys. In the end, the applicability of obtained analytical results is discussed, compared to the exact numerical solution.
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