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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Měření deformace statorového kroužku turbodmychadla při teplotním zatížení / Deformation measurement of turbocharger nozzle ring under temperature load

Kovářová, Lucie January 2019 (has links)
The thesis is about deformation measurement of the nozzle ring in variable nozzle turbine mechanism under temperature load. In the first part, there is a brief description of the turbocharger. In the second part, methods of deformation measurement are mentioned there. The main part of the thesis includes component testing of selected measuring methods and their application for measuring deformation of the nozzle ring on the turbocharger. Test is done on a gas stand which simulates the thermal load conditions of the turbocharger, same which is exposed to on the engine.
32

Analýza vlivu výrobních procesů na deformace kolejnic / Analysis of the Production Processes Influence on Rail Deformations

Skalník, Vít January 2020 (has links)
The aim of this work is to assess the possibilities of using numerical simulation tools in the process of laser welding of the guide rail of a car seat. In the diploma thesis, a description of the components and the problem, which consists in the deformation of the groove of the guide rail, was made. A description was made of the manufacturing operations that the components go through. The positives of selected welding methods were evaluated and the choice of those used in production was justified. A description of the issues of laser welding, deformation and the use of simulation tools was made. The influence of individual production operations was evaluated in terms of the size and nature of deformations. Using the Visual – Mesh, Visual – Weld and Visual – Assembly simulation tools, which are products of the French company ESI Group, the same state of the simulated and real process was achieved. Subsequently, a proposal for the elimination of deformations and its verification using a simulation tool could be approached. The use of a spacer wedge, which acts on the most deformed places of the groove, was proposed. By its application, the resulting deformations were eliminated or significantly reduced. In the last part of the work, a technical and economic evaluation was made, taking into account the current global crisis and the important role of the automotive industry.
33

Optimalizace výroby dutin v keramice s nízkou teplotou výpalu / Optimization of Cavity Fabrication in Low Temperature Co-fired Ceramics

Dóczy, Robert January 2014 (has links)
This work deals with the fabrication of closed cavities in Low Temperature Co-Fired Ceramics (LTCC). In recent years, the LTCC ceramics have become widely used in the areas of sensors, MEMS and micro-fluidic applications. When fabricating such devices, it is important that the cavities maintain their compactness and dimensions after the manufacturing process . This is achieved primarily with the right choice of lamination process and its parameters and also by appropriate setting of the firing profile. The theoretical part describes the various steps in the production of LTCC structures and the most common technological processes used for creating structures with cavities and micro - channels . In the practical part are selected laminating procedures performed on the test pattern, which contains cavities of different sizes. Emphasis was placed on the correct execution of each method , while gradually modifying the lamination parameters. The achieved results are further discussed in terms of process parameters and their influence on the dimensions of manufactured cavities.
34

Geodetické měření posunů a deformací dřevěné střešní konstrukce velkého rozpětí / Geodetic Deformation Measurement of Wide-Span Timber Roof Structures

Karas, Jindřich January 2013 (has links)
The aim of this thesis is deformation measurement of wide-span timber roof structures of swimming pool in Brno - Kohoutovice. The thesis deals with measuring of other stage, processing of surveying data, evaluation of deformation and graphic interpretation. Results of measurements follows up two stages in years 2009 and 2010. The part of the thesis is calibration measurement of surveying instruments and used measuring accessories.
35

Analýza deformačně indukovaných změn fázového složení oceli TRIP metodou EBSD / Analysis of Strain - induced Variations of Phase Composition of the TRIP Steel using EBSD Method

Pešina, Zbyněk January 2008 (has links)
The diploma thesis deals with phase composition measurement of the TRIP steel, using EBSD method. The steel was delivered as thermo-mechanically treated via two different routes. The phase composition of the steel was examined during gradual plastic deformation in the range 0 to10.99%. One route of thermo-mechanical treatment exhibited good agreement with the literature in terms of measured fraction of the retained austenite (15.6%) as well as its decrease during the deformation (to 8.9% at the maximum imposed strain). The samples of the second route did not show any agreement in either of the parameters spoken.
36

Optimalizace technologických parametrů vstřikování plastového dílce / Optimization of technological parameters of injection plastic parts

Hamáček, Richard January 2011 (has links)
This project is dealt with optimalization of moulding procedure of plastic housing of headlamp for project DCW 204 Mopf halogen. The aim is reach a shorter injection moulding cycle time with keeping of claim quality of plastic part. Optimalization will be done based on modification of moulding pressing time. We observe warpage in axis X in the most problematical points of housing by using of contactless measuring optical technologie ATOS III Triple Scan. Simulation analysis for injection moulding was used for prediction of housing warpage up to unforming in every chosen moulding pressing time. According to reaching data in this way comparison of predicted warpage was able to done up to unforming time and real warpage of housing after unforming. According to reaching data in a different period of time warpage of housing during time flowing was observed.
37

Vyhodnocení materiálových charakteristik při statických a dynamických zkouškách / Evaluation of materials characteristics exploiting static and dynamical tests

Riesner, Jan January 2011 (has links)
The project elaborated in frame of engineering studies branch M-STG describe characteristics of plasticity of non-anneal materials E 235, E 190 and E 220. Materials characteristic was receive by static and dynamical tests. Based on the literature study it was conducted survey of the current state of experimental techniques for high-speed deformation. The materials were designed by Holomon approximation of rigid-plastic material model without hardening. It was conducted force analyses for machine Unison MG 2790 for rewind bending and bend with compressive force considering the identified material model. It was describe the impact passive and active forces to move the neutral axis.
38

Predikce deformací svarových spojů pomocí počítačové simulace / Prediction of welding joint distortion by computer simulation.

Vaněk, Mojmír January 2012 (has links)
In this master’s thesis there are set down dependencies of distortion of T-joints on the size of heat input and welding speed. Dependencies were found for single- and double-fillet welds, for single- and multiple-pass welding. The computer simulations were carried out in programs Visual-Weld and SYSWELD. The size of the melted zones, stress fields, material structure and hardness of the weld specimens were specified. Simulation results were compared with experimentally detected values.
39

Optimalizace sběrného výfukového potrubí Škoda 1,2 MPI / Optimalization of Exhaust Manifold for Škoda 1,2 MPI

Kubiš, Milan January 2015 (has links)
The subject of this diploma thesis is optimalization of exhaust manifold of ŠKODA 1,2 MPI engine with respect for the plastic deformation at heat stress. The first part is focused on general description of converter module, whose component the exhaust manifold is. In the next part of the thesis is computation of a heat load of the exhaust manifold. The last part is devoted to the seal analysis of the whole converter module of a ŠKODA three-cylinder engine.
40

Návrh a sestavení laboratorního vzoru laserového deflektometru pro měření mechanického napětí v tenkých vrstvách / Design and set up of a laboratory sample of a laser deflectometer for measurement of mechanical stress within thin films

Šustek, Štěpán January 2016 (has links)
This diploma thesis describes the design of a device for measuring stress in thin films – laser deflectometer, realization of its design and its experimental testing. The thesis is divided into five chapters. The first chapter deals with the stress in thin films and its influence on substrate – thin film system. The second chapter provides an overview of devices widely used for measuring stress in thin films and describes some their advantages and disadvantages. In the third chapter some design possibilities of the device are presented. The final solution of device called deflectometr is introduced in the fourth chapter. The last chapter includes the functional testing the device.

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