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Stress-strain analysis of screw-bone system used in a plate-fixation of fractures
Kalnický, Jakub ; Valášek, Jiří (referee) ; Marcián, Petr (advisor)
In the field of orthopaedics and traumatology, a whole series of problems appear related to fracture fixation by means of various types of plates. Appropriate application of the plate is the difficult task that a doctor needs to deal with in the operating room. Regarding mechanics, the number of screws and their spacing have a major impact on the healing process. If there are too many screws or lack of them, the fracture does not heal properly. This can lead to implant failure. This work deals with stress-strain analysis of screws and bone tissue with a fracture fixed by LCP. It deals with the influence of different geometrical configurations of the screws on the stress, deformation and strain of the system. For this purpose, the computational modelling was used by means of the finite element method. Two computational models have been created, on which different screw arrangement was analysed. The first computational model represents diaphysis of the femur that is at the beginning of the healing process. For the four load models and eleven geometric configurations and number of the screws, a total of 44 computations were performed. The second computational model represents the distal part of the femur. Femoral geometry model was created based on CT (computed tomography) examination, geometric model of the plate was created by 3D scanning. Deformations and stresses were compared in the three geometric configurations of the screws during the healing process.
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Computational Model and Analysis of Vehicle Driving Dynamics
Mrázek, František ; Šimek, Václav (referee) ; Strnadel, Josef (advisor)
The bachelor's thesis deals with the creation of a computational model and analysis of vehicle dynamics in connection with the principles and rules that are closely related to vehicle dynamics. We will use the key physical phenomena related to the driving dynamics of the model vehicle, suitable for modeling and analysis. The model will demonstrate the driving dynamics of vehicles in several appropriately selected situations and creates the possibility to compare the results with data obtained from freely available publications and tests.
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Determination of pressure in the pipe using foil strain gauge
Beran, Vojtěch ; Dokoupil, Pavel (referee) ; Habán, Vladimír (advisor)
This master´s thesis deals with determination of pressure in the pipe using foil strain gauge. It is calculation of the pressure from the measured strain. The main purpose of this work is devise mathematical-technological models to determinate internal pipe pressure from longitudinal deformation. Devised models were used on data from realized experiment and results were compared with real value of pressures in pipes. This thesis contains three models which were mutually compared. Sensitivity analysis were done on two of these models. Thesis also contains opening research of strain gauge problematics. Description of basic knowledge of physical objects mechanic with focusing on shells also belongs to this theoretical part.
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Computational modelling of isovolumic contraction of left ventricle
Kubík, Matej ; Burša, Jiří (referee) ; Vaverka, Jiří (advisor)
This diploma thesis deals with computational modelling of isovolumic contraction of the left heart ventricle by using finite element method. Part of the thesis includes research on the anatomy and physiology of the heart, where the structure of the heart muscle is analyzed in more detail. The passive mechanical response of the model reflects this very structure. It is included in the computational model by using a reduced Holzapfel & Ogden hyperelastic model. The active tension of muscle fibers, which is a consequence of electrical stimulation, is included in the model by the so-called active stress approach. A main goal of thesis is the implementation and testing of this approach in ANSYS program with the help of subroutine Usermat.
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Computational Modelling of the Transmission Dynamic Behaviour
Švub, Pavel ; Řehák, Kamil (referee) ; Prokop, Aleš (advisor)
This thesis focuses on constructing a computational model of a gearbox using Matlab software, with the main objective of analysing the dynamic loads that occur during gearbox operation. The thesis examines the most important sources of dynamic forces in gear mechanisms, such as gear backlash, gear mesh stiffness, bearing stiffness, and shaft stiffness. Furthermore, it provides an overview of basic mathematical models used for modelling the dynamics of gear transmissions. Based on these findings, a custom model of a two-shaft gearbox is developed, which also allow gear shifting. Synchronization with a flexibly limited force is utilized for gear shifting. This model is then subjected to various loading conditions to monitor the response of individual components, including gear forces, bearing loads, and the magnitude of transmission error.
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Creation of a tool for calculating the efficiency of renewable energy sources
Lecián, Milan ; Zimáková, Jana (referee) ; Binar, Tomáš (advisor)
This diploma thesis deals with the design of a tool for calculating the efficiency and self-sufficiency of a mobile photovoltaic system to ensure the supply of electrical energy during crisis situations. The thesis includes research on various types of renewable energy sources and storage systems. Furthermore, it describes the relationships for calculating the position of the Sun, the intensity of the incident radiation, the efficiency and the output of the PV system and the overall coverage of the system’s consumption. Based on these relationships, a computational model is created. In the next section, this developed computational model is described and shows its application in comparison with the PV*SOL program. In the final part, using the analysis performed with the computational model, a design for o mobile photovoltaic system for supplying electrical energy during crisis situations is created using PV*SOL program. The use of the proposed system is demonstrated by providing electrical energy for emergency survival of the population. The conclusion of the thesis includes an evaluation and recommendations for further research.
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Adaptive Damping for Trucks
Neuman, Ondřej ; Hejtmánek, Petr (referee) ; Blaťák, Ondřej (advisor)
This diploma thesis is concerned with designing a computational model of a commercial vehicle. In addition to that, a control algorithm for adaptive damping is presented. These two parts are connected into a closed loop and together they create an adaptive damping system. The primary task of the algorithm is to react on a vehicle load change. Vehicle model has the opportunity to create different driving scenarios, which are used to verify algorithm functionality. With the help of computational model and optimalization process, suitable damping characteristics are derived. An evaluation of vehicle comfort and driving safety is also presented.
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Springing and Damping of Truck Cabin
Kroupa, Ondřej ; Vančura, Jan (referee) ; Blaťák, Ondřej (advisor)
This Diploma Theses, which can be included in the field of vehicle dynamics, explores the effect of suspension and damping of truck cabs for the safe ride and comfort. As the driver spends many hours in their vehicle, comfort is the most essential criterion. That is why we seek possible improvements which are offered by the sprung cab. The research part firstly analyses the individual elements of suspension and damping. The following chapter is devoted to the systems which are used nowadays in the construction of cabin suspension. Next there is the introduction to the theoretical production of a simplified computational model as well as the presentation of the possible evaluation of the achieved results. The following practical part deals with the actual shaping of the computational model in the Adams View software, which is based on a real vehicle, and was lent at the faculty. The model is then verified and compared with the existing state and the cab mounting concepts are tested on it. The effects of cab parameters on driving comfort and safe riding were tested on it as well. The last part focuses on the forming of the special Dakar computational model, on which optimization was performed according to the findings discussed in the previous chapter. Also, the appropriate configurations to the real-life testing were designed.
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Frame bridge
Kapsa, Štěpán ; Velešík, Marek (referee) ; Koláček, Jan (advisor)
The work deals with the design of a single-pole frame structure of a road bridge, which is based deeply on piles. Due to the size of the span of 26 m, additionally prestressed cables are designed in the supporting structure. The structure is analyzed by a three-dimensional bar model and assessed for serviceability and load-bearing limit states in the longitudinal and transverse directions. Part of the design is a study of the influence of supporting the computational model and a comparison of the effect of active and resting earth pressure on the structure.
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Design and static analysis of the lookout tower
Řehořová, Alena ; Hokeš, Filip (referee) ; Vlk, Zbyněk (advisor)
The topic of the bachelor's thesis is the design and static analysis of the steel structure of a lookout tower with a total height of 25.32 meters. The floor plan of each floor is a regular hexagon with a decreasing diameter to the center of height. The main viewing platform is located at a height of 24 meters, other viewing platforms are located in quarters of the height. The aim of the work is to design various structural solutions and their comparison, with respect to the effects of loading on the structure and its parts. The static model and calculation of internal forces is performed in the student version of the SCIA Engineer 20.0 program.
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