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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.
91

Vyhodnocení vlivu tvaru otvorů clonek na výsledný tlak na dráze sekundárních elektronů v detektoru pomocí systému CAE / Using Computer Aided Engineering for analyse the detector

Novotný, Marek January 2011 (has links)
This diploma thesis deals with electron microscopy. Examined equipment is environmental scanning electron microscope (ESEM), namely scintillation a detector of the microscope. There is solved the influence of the profile of holes in diaphragms to the resulting pressure and gas flow on the path of secondary electrons at the detector. Introductory part of thesis informs about microscopy in general, with concentration on electron microscopy; especially on scanning microscope, because research is taken just on the environmental scanning electron microscope. Another part informs about both general principles of dynamics of gases and with finite volume method. Another part deals with concrete used software and with setting of individual parameters for calculation. At the beginning of calculation are used five basic profiles of holes in diaphragms for pressure 1000 Pa in the chamber of the sample. For modelling individual shapes is used 3D parametric modeller SolidWorks. Analysis of circulation of secondary electrons through detector is made by using Cosmos FloWorks module. The most suitable type of diaphragms is chosen from measured models. Another part of diploma thesis deals with measuring of chosen types of diaphragms for more pressures in the chamber of the sample; the pressure is 200, 400, 600, 800 and 1000 Pa. The outcomes of this research are both models of pressure and speed of circulation inside the detector and graphically processed values by using different diaphragms, respectively one type of a diaphragm in different pressures. Production drawings of each diaphragm, together with calculated models, are enclosed.
92

Analýza rozložení tlaků ve variantě detektoru SE se třemi clonkami pomocí systému CAE / Analysis of pressure distribution in the variant detector with three aperture by CAE system

Tomášek, Martin January 2012 (has links)
This master`s thesis analyzes the pressure distribution on the premises of scintillation detector secondary electron in the variant with three aperture. The aim of this study is analyzing the fluid flow depending on the application of the third aperture in the entrance of the detector, thus creating more self-pumped chamber, which is responsible for ensuring a better distribution of pressure in the premises of the detector. The result of the analysis would be determining how to change parameters within the detector. If it is found that application of the third aperture has a positive effect on water flow in the premises of the detector, this arrangement may be used for improvement of the detector. Master`s thesis is divided into several chapters. First describes the basic principles of electron microscopy, including sample preparation, conditions for the proper functioning of microscopes and sharing different types of electron microscopes. The next chapters describe briefly the physical descriptions of gases flow in low pressures and small apertures, the mathematical models and simulation software used in this analysis. The analysis is done in SolidWorks with the module called Cosmos FloSimulation. The conclusion summarizes the results of the analysis, including graphical representations of simulation.
93

Implementace nových vzduchových jističů ABB SACE Emax 2 do produktové řady nízkonapěťových rozváděčů MNS / Implementation of the new ABB SACE Emax 2 air circuit breaker series in a low-voltage MNS switchgear product portfolio

Studený, Michal January 2014 (has links)
The Master’s Thesis comprises a summary of the differences existing design of MNS switchgear series against AGOMIN project innovative proposal. The introduction deals with the introduction to the CAD program SolidWorks and its extension for enterprise data management SolidWorks Enterprise PDM. The body of the paper deals with a new range of air circuit breakers ABB SACE Emax 2 and their implementation into the product line of low voltage switchgears. Included are other improvements that together with implementation of circuit breakers AGOMIN project brings.
94

Technologické postupy pájení pouzder QFN / QFN Packages Soldering and Technology Procedures

Jakub, Miroslav January 2015 (has links)
This master´s thesis deals with QFN packages soldering and technology procedures optimization. The aim of theoretical part is description of QFN packages, their assembly and reflow soldering on PCB in HONEYWELL. The aim of the practical part is to propose a method of measuring temperature and optimizing the thermal profiles of selected PCB with QFN packages by using convection (HONEYWELL) and infrared (BUT) reflow ovens. Comparison and evaluation of thermal profiles for 3 production PCBś with QFN packages using solder paste AIM NC257-2 were realised. The main part of master´s thesis are appearance evaluation of solder joints, preparing microsection and measuring intermetallic layers thickness by using the optical and the scanning electron microscopes, analysation and study of QFN defects created during soldering proces. These tests were performed with 2 production PCB´s. Optimization of SPI and soldering technology procedures where were analyzed QFN packages were processed on one type of PCB. Interesting part of this diplomma thesis is creating of the 3D heat transfer model of QFN package during the reflow soldering in SolidWorks.
95

Návrh 3D tiskárny typu delta pi s temperovanou podložkou s využitím systémů CAE / Design of delta pi 3D printer with tempered bed using CAE systems

Koudela, Ondřej January 2015 (has links)
This master's thesis deals with 3D printing using non-commercial 3D RepRap type printers. This work briefly describes development trends of non-commercial RepRap printers, theory of FDM print with analysis and comparison of materials, which are used in printing and the issue of the finite volume method and theory of heat diffusion. The practical part based on simulations from SolidWorks Flow Simulation discussed two basic methods of heating hot bed, then the temperature profile of hot end and the heat flow in full assembly of the printer. Outcome of this work is design an optimized model and the physical assembly of 3D printer delta pi type.
96

Optimalizace chlazení koncentrátorového fotovoltaického článku pomocí systémů CAE / Optimization of cooling the photovoltaic cell using CAE systems

Sodomka, Pavel January 2014 (has links)
This thesis deals with the optimization of the concentrate photovoltaic cell cooling system through the CAE system. In the theoretical part, the thesis treats there the problematic of the photovoltaics and focuses on the concentrator cell and its problems coupled with the cooling system and the sink of heat. In the next theoretic part, it also analyses there the problematic of the conduit and transfer of heat. Moreover, the mathematical description of the fluid flow, the finite-volume method that is used in the SolidWorks Flow Simulation for the calculations, are also described there. In the practical part, the models and steps which depict precisely all the process of the heat cooling optimization are mentioned. All the proposed variants are mutually compared and put up for the discussion about their advantages and disadvantages. Lastly, the resultant model was also put through the simulation with the suggested radiational component that gave precision to the results. In the end of the thesis, there was made out the documentation of the final model drawings.
97

Analýza tvaru sacích kanálů současné koncepce diferenciálně čerpané komory / Analysis of the shape of the intake ports of the current concept differentially pumped chamber

Bílek, Michal January 2015 (has links)
This master´s thesis discusses the analysis of the shape of the intake ports of differentially pumped chamber for the current concept. The first part is an introduction to the microscopy issue, then it is focused on ESEM microscopes and it also includes a describtion of the Flow dynamics and a mathematical describtion. In the following chapters the software Solid Works, where the model of differentially pumped chamber is created, and the software Ansys Fluent, which is used for analysis, are described. The second part concerns the proposed concepts and the results of their simulations. At the end of the work the results are analyzed and evaluated.
98

Návrh modelu prádelny budoucnosti / Design of up-to-date laundry premise model

Marek, Tomáš January 2010 (has links)
Scope of this thesis is the design and evaluation of a laundry processing facility. Main goal was to prepare, design and evaluate part of the technological layout for a modern, high-volume laundry processing facility. The focus was on the main apparatuses, main process flow, as well as the supporting process flow, related equipment and key components of field instrumentation with standard description. 3D facility model was prepared on the basis of proposed technological layout, using the SolidWorks software package. This model shows placement of all key equipment and components as well as physical disposition of connection tubing within the building. Final part of work reviews proposed options of process parameters measurement. Such measurements which are important for the evaluation of energy consumption of considered laundry processing. We discuss both pros and cons of evaluated and selected suitable measurement devices, tools and procedures. Constructed 3D model of piping lines shows placing and dimensions of selected measurement devices.
99

Analýza vlivu proudění plynu v oblasti umístění vzorku v komoře enviromentálního rastrovacího elektronového mikroskopu / Analysis of the influence of the gas flow in the placement of the sample in the chamber of the environmental scanning electron microscope

Bednář, Eduard January 2016 (has links)
This thesis deals with the simulation of fluid dynamics in environmental scanning electron microscope and evaluate solvers setup, the degree of discretization, choice of turbulent model and proposal optimal design of environmental scanning electron microscope. The theoretical part describes the issue of environmental scanning electron microscopy, software SolidWorks and ANSYS Fluent, basic equations describing fluid status, fluid turbulence, the mean free path of molecules and electron scattering. The practical part of the thesis is to create the model of environmental scanning electron microscope AQUASEM II in CAD system SolidWorks and simulation of fluid flow in the sample chamber before aperture PLA1 by ANSYS Fluent. A series of simulations provided the perfect setting solver. These knowledge are used in the second stage of the practical part, where is proposed optimal shape of the table sample and the input aperture PLA1.
100

Působení sekundárních elektrických přístrojů na oteplení skříně rozváděče. / Influece of secondary apparatuses on assembly box heating

Dobiáš, Pavel January 2016 (has links)
This master's thesis deals with the temperature-rise of selected parts of the low-voltage switchgear. The theoretical part describes the physical principles and the basic mechanisms of heat transfer. The next part describes the possible effect of elevated temperature on the device inside the switchgear. The master's thesis is awarded by ABB Ltd., so another part is dedicated to MNS switchgear. The following part describes the permitted limit of temperature-rise of switchgear in accordance with IEC 61439-1. In the practical part is a calculation temperature-rise of selected part of switchgear based on IEC 60890. Model in SOLIDWORKS Flow Simulation was created for the same part of the switchgear and thermal analysis was performed. The values of allowable temperature rise of individual parts are compared with the results obtained by calculations and simulations. In the last part is verified the possibility of calculating the temperature-rise in the EPLAN software.

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