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Gear coupling modification
Mahel, Pavel ; Prokop, Aleš (referee) ; Řehák, Kamil (advisor)
This thesis deals with the design of a gear coupling. The main intention is to design the optimal shape of the clutch gearing for the given operating conditions. Due to the special barrel shape of the teeth on the external gearing, these couplings enable the torque to be efficiently transmitted even in the case of misalignment of the connected shafts. In the case of an improperly designed coupling, a number of problems can occur that could affect the life of the coupling. These problems include in particular the generation of excessive vibrations and noise. It is necessary to choose the right lubrication system for long-term coupling life. To eliminate problems with gear couplings, it is necessary to ensure a suitable distribution of contact pressure at a given degree of misalignment. The introductory part of the thesis contains a comprehensive view of the issue of gear couplings. The next part deals with the structural design of the whole gear coupling and the improvement of the existing model. The following is a description and analysis of two different computational models of gearing that allow for different maximum degree of misalignment. The difference between the two gearing models is in the different geometry of the tooth shape on the hub. In the computational analysis, the most important monitored parameter was the course of contact pressure on individual teeth at a given degree of misalignment. From the performed computational analyses, result files are processed that compare the contact pressure and the number of teeth in engagement for different degrees of misalignment. The above analyses were performed using the finite element method in the calculation program Ansys Workbench.
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Stress-strain analysis of the LKDS800 frame
Tománek, Jiří ; Vlk, Miloš (referee) ; Vosynek, Petr (advisor)
This diploma thesis deals with frame of the two-point crank press LKDS800, which was designed by company ŽĎAS a.s. Frame is welded construction creating the base of the press which has mass approximately 90 tonnes. Aim of this study was to perform strain-stress analysis of the frame. From obtained results perform optimization of mass this frame leading to reduce material costs and machining. In the process is frame loaded by nominal forces from the shearing process, under its own weight and inertia forces caused by moving components. As a result of the dynamic loading in welded joints there are risks of fatigue fracture. The manufacturer of the press is required to find the most loaded welded joint and it to assess the fatigue life.
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Strain stress analysis of BS splint
Řehák, Kamil ; Fuis, Vladimír (referee) ; Florian, Zdeněk (advisor)
This master‘s thesis deals with strain-stress analysis of hip joint together with the final applied total endoprosthesis with Burch-Schneider cage. The main point of my work was to find the solution of stress–strain analysis state, which has been mentioned before in connection with Burch-Schneider cage. I describe the technique of geometric creation of whole body system, component´s materials or conditions which are neccessary for calculation. In coclusion there are results achieved in variants. In the first option the case of bone tissue was considered, which don’t reach degradation mechanical properties effect straining under Burch-Schneider cage. In some cases when the bone tissue is untimely forced, the necrosis of bone tissue takes place under Burch-Schneider cage. This possibility is described in the second option of type. For every option there was a case which was calculated with applied screw or without it. In all option mechanical features of cancellous bone tissue and their change influence on achieved results were considered. This problem was solved computational simulation in commercial software Ansys Workbench 12.0.
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Design of gear coupling
Kundýsek, Michal ; Prokop, Aleš (referee) ; Řehák, Kamil (advisor)
The content of the diploma thesis is the construction of a toothed coupling for general use. The coupling was first described in order to acquaint the reader with the issue of the coupling. After approaching the issue, a practical part was created, which dealt with the conceptual design of the gear coupling. Two gear coupling designs have been developed to take into account as many customer requirements as possible. After making the model, strength calculations were created to verify the functionality of the coupling. The calculations mainly concerned important components for the operation of the clutch.
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Biomechanical study on upper extremity fixation
Rafaj, Svatomír ; Marcián, Petr (referee) ; Florian, Zdeněk (advisor)
This bachelor’s thesis deals with fixation and biomechanical aspects of fractures of the upper limb. The first part of the thesis discusses anatomy, knowledge of which is necessary for effective fixation of fractures. It describes the history of inner fixation of fractures and modern curing methods of fractures with a focus on locking compression plates. The second part of the thesis discusses strain-stress analysis of assemblage of humerus and applied locking compression. Computational model was created with the support of ANSYS Workbench 16.0 and SOLIDWORKS 2016 software. Computation was executed by finite element method using ANSYS Workbench 16.0 computational systém.
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Computational analysis the state of stress of turbine blade
Klement, Jan ; Žatko, Miroslav (referee) ; Malenovský, Eduard (advisor)
This diploma thesis continues to the Ing. Damborský work and deals with strain-stress and dynamic analysis of the steam turbine blade. This blade is part of the last row of low pressure level of steam turbine. Computational analysis has been performed in first part using FEM. After that follows a modal analysis for the blade without residual stress as well as for the blade affected by heat treatment. Main goal is to obtain whether the state of stress is in the crack initiation area is influenced by thermal treatment. This problem was solved by computational simulation in commercial software Ansys 11.0.
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Strain-stress analysis of gear coupling
Vondra, Róbert ; Prokop, Aleš (referee) ; Řehák, Kamil (advisor)
This thesis deals with the contact analysis study of crown gear couplings during the simulation of its working conditions. The toothed coupling transmits high torque, even when the input and output shafts are misaligned due to outside tooth shape. For this reason, it is necessary to design the gear shape correctly. The inherent use of toothed couplings results in a wide range of working speeds and load transfers. This can cause several problems, if the parameters are selected incorrectly. Among the most significant of these is the generation of vibrations during gear engagement, accompanied by noise and the excessive loading of components, such as shafts and bearings. It is not possible to completely reduce uneven running, even with knowledge of the latest trends in the field of gear development. For this reason, it is necessary to eliminate the paths where the vibrations can propagate during the design itself. Inefficient and costly experiments are often used to determine the correct shape of gear teeth. For this purpose, a computational approach to describe a contact pressure on the teeth of couplings at different misalignment and loads is proposed. The model helps to understand the composition of the contact pressure during the working mode of misalignment and its behaviour within the rotation of the gear coupling. The introductory part of thesis presents the current state of knowledge of gear couplings and a description of load distribution issues, regarding the angular misalignment, torque and friction. In the following chapter, three possible approaches to the problem are described - analytical, experimental and computational. The following work offers the introduction and creation of two different computational models, varying in different tooth shape on the hub and the sleeve. Each geometry was subjected to a different load moment, a misalignment of the hub, or the rotation of the gear coupling as a whole. The main monitored parameter was the course of contact pressure in each step, when changing the degree of misalignment or the rotation of the model. Finally, three main sets of contact pressure on the teeth are presented, in connection with the reduced pressure plotted on the toothed rings. There is derivation of results and mutual comparison of each load case. The computation approach in FEM program Ansys Workbench was used to solve the problem.
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Strain-stress analysis of spinal segment
Pánis, Vladimír ; Janíček, Přemysl (referee) ; Návrat, Tomáš (advisor)
Presented work deals with the strain-stress analysis of a spinal segment while monitoring the influence of total disk replacement Maverick on the global behaviour of the spinal segment. It also assesses the influence of this implant on the nearest upper intervertebral disk. On the basis of CT images was in the program Rhinoceros created the geometry model of spinal segment Th12-L2. The geometry model of implant was applied between vertebra L1 and L2 instead of intervertebral disk from which the whole core was removed, while in the immediate surrounding of implant the part of disk was left, which is important from the view of stability. Subsequently were in the program Ansys Workbench created finite element models for two states: - healthy (unbroken) status - status with applied implant Then the calculations for movements were realized: lateral flexion, flexion, extension, rotation. For the same movements were realized calculations of the model simulated spinal fusion of the vertebras L1-L2. Finally an influence both of methods (total disk replacement, spinal fusion) on the intervertebral disk Th12-L1 was compared.
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