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Výpočtová simulace rovnání trubek / Computational simulation of leveling of pipesPeter, Ondřej January 2017 (has links)
The master thesis deals with the computational simulation of cross-roll leveling of tubes with various degrees of thickness. Based on the Lagrange approach, a several FEM models of curved tube were developed and subsequently solved in ANSYS commercial software. Furthermore, a several models of curved tube were solved by algorithm based on the Euler approach created at UMTMB FME BUT. Based on the comparison of output parameters from both algorithms it was found that the output parameters are comparable to the d/D ratio (inner/outer diameter of the tube) = 0.43.
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Analýza procesu ohybu trubky / Analysis of Tube Bending ProcessŠrom, Jan January 2017 (has links)
Master thesis analyzes rotary draw bending of the tubes without using a mandrel. Bending process is accompanied by many defects due to large displacement of formed material. One of the major defects is flattering of the cross section also called ovality. In order to decrease ovality comes up a proposal of the changes to the tool design. Modifications of tool’s geometry are numerically analyzed by finite element method in software ANSYS. According to the results of the simulations an optimized pressure die is manufactured. Several experimental tests are accomplished to verify the effect of the optimized tool design. Approximately 100 bends confirm a decrease of ovality using modified pressure die.
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Parní kotel na odpadní teplo z kogenerační jednotky / Heat Recovery Steam Boiler for Cogeneration UnitVilga, Filip January 2017 (has links)
The main goal of this Master's thesis was to design heat recovery steam boiler for cogenera-tion unit of a biogas plant while flue gas was flowing from an engine exhaust. Its temperature and required pressure of a steam were assigned. The thesis contains thermal, aerodynamic, hyd-raulic calculations and verification of wall thicknesses for pressure parts of the boiler. Follow-up results of these calculations served for making of projection drawings as well as equipment needed for reliable boiler operation.
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Rekuperace tepla z odpadních plynů tavicí pece / Heat recovery from melting furnace waste gasesDobai, Szabolcs January 2019 (has links)
This master’s thesis deals with the design of heat recovery system from melting furnace waste gases. The first part is devoted to a brief description of heat exchangers, with the special importance being placed on the shell-and-tube heat exchanger. The second part contains a calculation of stoichiometric combustion, design of geometrical dimensions, calculation of pressure drops and power. At the end of the thesis there are various possibilities of utilization of the obtained waste heat and their basic economic assessment.
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Cavitation Induced by Rotation of Liquid / Cavitation Induced by Rotation of LiquidKozák, Jiří January 2020 (has links)
Tato disertační práce se zabývá experimentálním a numerickým výzkumem kavitace vyvolané rotací. Pro potřeby tohoto výzkumu byla využita transparentní osově symetrická Venturiho dýza, díky čemuž bylo možné zkoumat dynamiku kavitujícího proudění pomocí analýzy vysokorychlostních nahrávek.
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Příprava kalibračních měrek pro metodu zkoušení vířivými proudy / Preparation of calibration gauges for eddy current testing methodMachovič, Daniel January 2020 (has links)
The aim of the diploma thesis is to clarify the topic of calibration samples used in eddy current testing on equipment in nuclear energy. The theoretical part of the diploma thesis is focused on the eddy current testing method, which belongs to the technology of non-destructive defectoscopy. This part of the work describes the principle of the method, its scope, limitations and dividing of sensors used in this test method. The work briefly describes the physical principle of the laser, its types and operating modes. The practical part of the work is focused on the production of a calibration samples by laser. Another point of the work is the comparison of data obtained from eddy current measurements on samples made by laser and on calibration samples used in practice.
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Stanovení akustické pohltivosti materiálu / Determination of the Material Acoustic ImpedanceVozárová, Juliana January 2020 (has links)
This diploma thesis deals with the determination of the material acoustic absorption in an impedance tube. The aim of the work is to propose a measuring experiment and to design measuring device with the intention of reducing costs. The aim is to carry out a measuring experiment on a manufactured measuring device. The results of the experiment are evaluated in terms of meeting the requirements formeasuring device. The results of the tested materials are compared with the values from the supplier.
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Generation and Analysis of Streamwise Vortices from Vortex Tube ApparatusCarlson, Bailey McKay January 2020 (has links)
A pressurized vortex tube is used to generate streamwise vortices in a wind tunnel and the resulting flow behavior is analyzed. The apparatus is intended to verify computational data from the AFRL by offering a method of conducting real-world counterpart experiments. The apparatus design process and other considered approaches are discussed. The vortex tube is operated at pressures of 20, 30 and 40 psi while the wind tunnel is operated at 3, 5, 10 and 20% capacity. Flow measurements are performed using particle image velocimetry to observe vortices and freestream interactions from which velocity and vorticity data is comparatively analyzed. Results indicate that vortex velocity greater than freestream flow velocity is a primary factor in maintaining vortex structures further downstream, while increased supply pressure and reduced freestream velocity also reduce vortex dissipation rate. A brief analysis of the vortex interaction with a downstream airfoil is presented to support future work.
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Modeling of Cold Pilgering of TubesAzizoğlu, Yağız January 2017 (has links)
Cold pilgering is a challenging tube forming process in terms of modeling due to the complexity in kinematic of tools, friction condition and material behavior. The process development has mostly been based on simple formulas and costly full-scale tryouts. The aim in this study is to develop validated Finite element models of cold pilgering to increase the understanding of influence of the process parameters on the produced tubes. In the course of this thesis, three-dimensional mechanical and thermo-mechanical Finite element models of cold pilgering were developed. The commercial code MSC.Marc was used in the simulations. General 3D models are needed to be able to capture asymmetric deformation in cold pilgering. It was found that tool deflections together with elastic deformation of roll dies have considerable influence on the rolling force. Furthermore, the strain rate and temperature effects on the response of the material and thereby on the rolling force were evaluated.
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Thermal modelling of feedwater heatersAllie, Mohammed Nazier January 2016 (has links)
Manufacturers of feedwater heaters (FWHs) are obliged to disclose a specification sheet to the client that describes their FWH design. However, the client is unable to verify the performance of this FWH design without comparing it to the results that are predicted by a thermal model. An additional limitation is that the manufacturer will only disclose the minimum number of design parameters. The purpose of this study was to develop a thermal model that can predict the performance of a FWH. The model requires the minimum design input data to predict the performance parameters that may be compared to values predicted by the vendor. A FWH in a regenerative water-steam Rankine cycle achieves heat transfer to the feedwater by condensing steam on the shell side. This is called a single zone FWH. The tube plate type FWH is the most common type of FWH referenced in literature but the following variations may exist: • The Eskom fleet consist of both tube plate and header type FWHs. • FWHs may be orientated vertically or horizontally. Internal shrouded regions, that define it as a 2 or 3 zone FWH, may be present in the FWH. The length of the drains cooler (DC) zone may either be identified as long or short. A general model was required to capture all these design variations. Plant visits were arranged with engineers at several power stations to obtain the minimum input data and to confirm that these FWH design variations existed within the Eskom fleet. The model was based on existing tube plate models found in literature. It was then extended to accommodate the FWH variations mentioned above. A further improvement was made by including an additional heat transfer sub-zone that removes excess superheat in the condensing (COND) zone. The vendor does not disclose the correlations used to predict the film heat transfer coefficients (h) in their design. Therefore, the user is granted the option of selecting a correlation from a list of popular correlations, specific to a heat transfer mode. Note that the uncertainty associated with this thermal model is affected by the uncertainty of each correlation selected in the model.
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