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Modern motor vehicle batteries
Komárek, Radim ; Šebela, Kamil (referee) ; Štětina, Josef (advisor)
In response to pressure from the European Union to reduce emissions, requirements on car manufacturers are increasing, paving the way for a shift from traditional internal combustion engines to electric drives with energy stored in batteries. The battery itself is made up of modules in which battery cells are stored. To get the correct voltage output, the battery modules and the cells in them need to be wired. Where parallel wiring of the cells with serial wiring of the modules is most appropriate. The most commonly used cells are cylindrical and prismatic cells, which are further divided into prismatic cells and pouch cells. Cylindrical designs are suitable for applications where maximum power output is required, while prismatic designs are better in energy efficiency. Thermal management is very important to keep the batteries within a narrow temperature window. Liquid cooling is preferably used, which has an order of magnitude higher efficiency. This thesis focuses on the analysis of these technologies and their impact on the efficiency and lifetime of battery systems in the automotive industry.
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Thermal simulation for space applications
Kostelník, Tomáš ; Maxa, Jiří (referee) ; Vyroubal, Petr (advisor)
This master´s thesis is focused on the problem of modelling heat transfer in Earth orbit. In the theoretical part, the main types of standard orbits are described, including terminology related to this issue. Furthermore, the subsystems of space probes are described with a focus on a specific description of their functions. The thesis also includes a discussion of the issues related to thermal management of space satellites, with a focus on multilayer insulation and thermal surface finishes. The work also includes a description of the various mechanisms of heat transfer in space, with a deeper focus on thermal radiation heat transfer, which is key in the context of this thesis. The experimental part is focused on the design of a calculator focused on the computation of radiation boundary conditions for different orbits of a space vehicle and their verification using a CFD solver on a model example of a cubesat.
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Integration of MHS into microsatellite for qualification mission
Macejko, Jakub ; Götthans, Jakub (referee) ; Götthans, Tomáš (advisor)
Tato diplomová práce se zabývá proveditelností demonstrační mise za použití CubeSatu, která by měla kvalifikovat miniaturizovaný tepelný spínač pro vesmírné aplikace. Studie posuzuje různé konfigurace CubeSatů od 1U do 3U se zaměřením na jejich schopnost provádět potřebné tepelné testy. Zjišťuje, že zatímco menší konfigurace poskytují nákladově efektivní testovací platformu, větší konfigurace nabízejí komplexní testovací možnosti.
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Utilization of light emitting diode lighting
Podola, David ; Černý, Michal (referee) ; Paloušek, David (advisor)
This bachelor thesis deals with problems of illumination by LED diodes. Basic concepts of lighting technology are defined in the first part. The second part is dealing with the construction of body LED diodes and explains the principle of white light formation to LED. Introduces problems of cooling. Gives an overview of the available power sources for LEDs. Provides an overview of how to control lighting by using motion sensors and presence sensors. Will be made basic economic balance sheet, which will evaluate the advantages of using LED sources. Attachments provide the LED catalogs of manufacturers, accessories for LED and comment on other sources of information.
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Emisivity and its Impact on the Heat Conductivity
Gančev, Jan ; Hejátková, Edita (referee) ; Szendiuch, Ivan (advisor)
This work deals with the issue of emissivity and its impact on the heat dissipation.The first part describes the basics of thermal management, the issue of emissivity and its measurement. In the second, experimental part, are dedicated the emissivity values of examined specimens. These values are then used as initial conditions for the thermal simulation. In the last part are compared the measured results and the simulated results and is evaluated the impact of emissivity for the heat dissipation.
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Optimization of the printed circuit board for power LED
Schenk, David ; Klíma, Martin (referee) ; Ing. Josef Vochyán, Ph.D., ALCZ Jihlava (advisor)
This diploma thesis deals with the problems of heat transfer on printed circuit boards. The first part consists of a theoretical analysis of the principles of conduction of heat in different environments, comparing the properties of common type’s base materials for PCBs in terms of thermal properties and focuses on heat transfer from the chip. In the following part they are general information about the program ANSYS ® Workbench ™. Next part consists of the basic designs of PCBs and their improving. PCBs thermal properties for different configurations are verified with calculations, simulations and practical measurements. In the last part there are created design recommendations for PCBs design based on the comparison of the results of initial proposals and proposals to improvements.
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Modern Trends in Vehicle Front Lights Design
Rada, Jakub ; Maršálek, Ondřej (referee) ; Raffai, Peter (advisor)
This bachelor’s thesis deals with the modern trends in the design of the headlamps. The first part presents the sequential stages of development of systems used for headlamps and their design solutions. The second part focuses on the possible cooling alternatives of functional parts in lighting modules, completed with the results of comparative laboratory tests performed by front manufacturers of automotive lighting. The final section contains a comparison of the currently most widely used technologies in the vehicle front lighting.
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Development and design of a modular battery box.
Rozinek, Josef ; Buday, Vladimír (referee) ; Porteš, Petr (advisor)
Tato práce se zabývá problematikou battery packů. V první části popisuje návrh battery packu z hlediska volby baterií, jejich tvaru, velikosti, typu a konfigurace zapojení. Dále uvádí vliv těchto charakteristik na výkonnost battery packu a jeho spolehlivost. Zabývá se problematikou termálního managementu battery packů a jeho vlivu na životní cyklus baterií. V druhé části se zabývá praktickým návrhem konceptu battery packu pro Lithium-polymerové baterie. Kalorimetricky je zde zjištěno množství produkovaného tepla při vybíjení, které je poté využito v CFD simulaci chlazení článku.
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Influence of temperature on light-technical parameters of LED
Sláma, Pavel ; Štěpánek, Jaroslav (referee) ; Pavelka, Tomáš (advisor)
This thesis deals with LEDs and how temperature influences their parameters. In the first part it is analyzed how semiconductors and semiconductor junctions work, which is fundamental for understanding mechanisms of diodes. Next up is description of electroluminescence and basic description of physical principles, on which it works. Following part is supposed to introduce reader to electro-technical parameters and powering possibilities of LEDs. Following chapter focuses on description of lightning-technical parameters. It aims to describe their meaning and their relation to LEDs. Next part is about influence of temperature. Firstly, it names the parameters which are altered by temperature change. Follows the description of thermal management and its influence on right behavior of LED diodes. The last part contains construction of measuring workplace for analyzing temperature influence on lightning-technical parameters of LEDs. Measurement of chosen electrical and lightning parameters follows up.
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Simulation of heat dissipation for power component
Sedlář, Tomáš ; Macháň, Ladislav (referee) ; Čožík, Ondřej (advisor)
The diploma thesis deals with the simulation of heat dissipation for LED Seoul SZ5-P. The heat transfer is discussed first. Further, the issue of thermal management and its design is analyzed. The dependence of LED junction temperature on area of single and double layer printed circuit board is simulated with Ansys Icepak. Additionally, influences of the number and placement of vias on the printed circuit board and aluminum substrate printed circuit board are simulated. Last but not least, the equations describing the dependence of printed circuit board area on desired LED junction temperature are derived. Finally, the values of heat transfer coefficient including convection and radiation are determined for various heat losses and junction temperatures.
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