Předložená disertační práce se zabývá experimentálním studiem modifikátorů tření a maziv pro temeno kolejnice, které jsou aplikovány do kontaktu kola a kolejnice za účelem optimalizace adheze a redukce hluku. Hlavním cílem práce bylo objasnit vliv aplikovaného množství a složení těchto látek na adhezi v kontaktu. Hlavní pozornost byla věnována zejména potencionálním hrozbám souvisejících s kriticky nízkou adhezí, která může nastat po aplikaci těchto látek. Experimentální studium probíhalo v laboratorních i reálných podmínkách, konkrétně v tramvajovém provozu. V případě laboratorních experimentů byl využit komerční tribometr a dvoudiskové zařízení umožňující simulovat průjezd vozidla traťovým obloukem. Kromě samotné adheze bylo při experimentech sledováno také opotřebení a míra hluku. Výsledky ukázaly, že maziva pro temeno kolejnice jsou schopna poskytovat požadované třecí vlastnosti, nicméně jejich chování je silně závislé na aplikovaném množství. V případě předávkování kontaktu dochází ke kriticky nízkým hodnotám adheze, které vedou k výraznému prodloužení brzdné dráhy. V případě modifikátorů tření bylo ukázáno, že chování těchto látek je výrazně ovlivněno odpařováním základního média. Výsledky také ukázaly, že nadměrné množství částic pro modifikaci tření může způsobit kriticky nízké hodnoty adheze. U obou výše zmíněných typů produktů byl prokázán pozitivní vliv na míru opotřebení a míru poškození povrchu, zatímco významná redukce hluku byla dosažena pouze v případech, kdy došlo ke značnému poklesu adheze. V závěru této práce jsou uvedena doporučení pro další výzkumné aktivity v této oblasti.

This diploma thesis deals with design of a wheel hub assembly for a Formula Student vehicle. First part of this thesis is dedicated as an introduction to the Formula Student competition and serves as a summary of design solutions for wheel hubs with a focus on open wheel vehicles. Second part deals with description of a problem and summarizes necessary knowledge and information to solve given problem. Third part is devoted to CAD modelling in software PTC Creo parametric. This model is then analysed using finite element method. Last part of this thesis is a discussion about achieved results and discussion about further potential improvements is carried out.

This diploma thesis is dedicated to the development of mobile resonance-adhesion tester TriTec. The aim of this thesis is to improve the parameters of the tester in comparison to the previous version of tester, especially to minimize the vibrations of the tester while running without load, and to the make long-distance transportation of tester easier. The first part of thesis was aimed on history of development of TriTec tester, causes of it´s problems and on analysis of vibration minimization possibilities. As a best solution is considered a rotational balance mechanism, which was designed in next part of thesis. After that a new front wheel drive and an user interface conception were designed. The modified tester reaches all the deserved parameters and is able to compete static resonance-adhesion testers by it´s lower price and high mobility.

The master thesis deals with the influence of a local change of temperature due to advection from disc brake to axial velocity field close to the rotating wheel of a car. The second goal is to set parameters applicable to various wheel discs and study of the influence of these parameters to aerodynamical properties of car and thermodynamical properties of the disc brake. The thesis is numerically executed in StarCCM+. The first part focuses on theoretical background about the numerical solution and current status of research. There are described disc parameters, geometry input and solver settings in the second part. The final part deals with a comparison of velocity fields for isothermal and thermodynamical model and evaluates the influence of parameters to velocity field, aerodynamical drag and thermodynamical performance of the brake.

This Master’s thesis is focused on the suspension of the front wheel, more accurately for specific part, upright. It describes the basic requirements for construction, distribution of uprights, their method of production and types of materials used. It briefly mentions topology optimization and its two optimization methods. Also deals with vehicle dynamics for driving conditions – standing vehicle, braking and cornering. In the practical part, the work is focused on determining the load effects on the upright during the aforementioned driving conditions using MBS software. At the end of the work, FEM stress and deformation analyses are performed for loading on the wheel side and on the suspension side, which are then compared and evaluated.

The master thesis deals with the currently used types of water turbines and next part of the thesis deals with the theory of Tesla turbine. The theoretical part discusses water wheels, water turbines with their types and models which are described in the work. The thesis also discusses the construction of the Tesla turbine, its possibilities of using, inside principles and information about Tesla´s patent. The practical part contains the design of the Tesla turbine with modifications for increasing efficiency. The thesis describes production and assembly of turbine and the technology used for production of the turbine. There is also described how the turbine was measured and there are results of measurements of the turbine.

This master‘s thesis deals with a centrifugal pump running in reverse (turbine) mode, often called “pump-as-turbine”. The introduction lists basic principles and information about the direct (pump) and reverse modes. Several methodologies for predicting reverse operating point and efficiency evolution are used and compared with simulation results. Using CFD simulations, results obtained with simplified (excluding impeller side wall gaps) and complete geometry (including impeller side wall gaps) are assessed. Furthermore, the results of impeller trimming are evaluated with an aim to find the maximum power and efficiency. Impeller side wall gaps effect is analyzed in terms of friction torque and power loss.

This thesis solves the problem of design and production of a special mounting device for the impeller nut of the main circulation pump GCN-317. The proposed device is intended to solve the problems associated with the mounting and dismounting of this nut. The work provides basic information about the Dukovany Nuclear Power Plant and VVER-440 systems in general, including their brief history. It also introduces the operational and legislative environment of the primary circuit of the nuclear power plant. It deals with the task and technical description of the main circulation pump and its overhaul. The following sections present the basic principles of construction of the device and an overview of its components with a description of their purpose and method of production. The last part of the thesis describes the function of the device and its verification and reports on its deployment.

This thesis deals with the conceptual design of a double clutch gearbox and the inspection of selected designed parts of this gearbox. The first part of the thesis is focused on the theory of automotive transmissions and analysis of already available double clutch gearboxes. The following is the conceptual design itself, which is based on the selected vehicle on which the transmission will be located and on driving resistances. Based on these default values, the gear graduation is selected, which affects the vehicle’s driving dynamics. With regard to the installation space, a conceptual arrangement of the gearbox is proposed. Furthermore, the thesis is focused on the basic design and calculations of individual functional components of the gearbox. The last part of the thesis is involved to the control of selected structural nodes using the finite element method in the ansys workbench software. The whole thesis describes the individual steps for the design of the basic concept of a double clutch gearbox and the design of their basic components.

This Diploma thesis deals with the design of facilities for measuring wheel alignment and set-up of race car chassis. Two versions of measuring system have been elaborated, each measurement procedure is described. Stress analysis of main parts follow. The last part consists of factors affecting accuracy of measurement.