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Hydrogen fuels
Umlauf, Martin ; Bébar, Ladislav (referee) ; Jícha, Jaroslav (advisor)
Paper presents a basic review and comparison of energy-conservation made of renewable sources. Principal question of paper concerns evaluation of hydrogen-use made of electrolysis of water. First part of the thesis focuses on the production of energy from renewable sources and the possibility of energy-accumulation. The next section describes methods of hydrogen production and utilization of hydrogen as a fuel for combustion engines. Attention is paid to various aspects dealing with construction of combustion engines using hydrogen. Final part of the study presents comparison between combustion engines using known sorts of fuels as to their pollution and emission-level. Next comparison deals with economic cost per kilometer, when different sort of fuels are taken into account. Conclusion concerns approximate calculation of the production of hydrogen from water by electrolysis using photovoltaic power plants.
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Determination of Hydrogen Mixture Influence on Internal Combustion Engine
Roušar, Jiří ; Dlugoš, Jozef (referee) ; Novotný, Pavel (advisor)
The aim of the Bachelor thesis is comparing a hydrogen combustion engine with conventional combustion engines and comparing the advantages and disadvantages of the hydrogen combustion engine. The features of hydrogen are introduced, as well as its production, transportation and storage. The work contains a research of construction designs of a conventional engine modifications to the hydrogen engine. The realisation of technically possible modifications to the conventional engine is included in the thesis.
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Hydrogen production from renewable energy source
Lakva, Petr ; Baláš, Marek (referee) ; Jícha, Jaroslav (advisor)
Hydrogen, as a form of storage for the excess energy from renewable sources, is a technically and economically viable option. However, the technology is not mature enough to compete with the other renewable energy possibilities. In this thesis, a study based on coupling two 330 kW wind-turbines with an NELP. 40 electrolyzer this connection should improve the utilization of wind power. In this thesis are two options of energy utilization. The energy produced by the wind-turbine is stored in the form, of hydrogen and is then delivered for consumption at variable power through a fuel cell, second option is use of produced hydrogen as alternative fuel for cars. This study is a general introduction for the wind energy system with hydrogen storage. Future studies should be more complex and detailed in order to understand and model the system with greater accuracy and to increase the possibility for the utilization of wind energy to generate hydrogen. This would enhance wind power competitiveness and sustain the continuously changing world energy demands.
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Electrolyzer for hydrogen production
Kunovjánek, Miroslav ; Knotek, Tomáš (referee) ; Sedlaříková, Marie (advisor)
The work is concerned with a production of hydrogen and oxygen through by the help of electrolytic process in a device called electrolyzer. The basis of the work is assurance of the best efficiency of this process by testing a variety of materials and surfaces of electrodes, and testing different types of alkalic electrolytes.
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Plasma diagnostics of electric discharges generated in selected configurations in liquids
Vašíček, Michal ; Bartlová, Milada (referee) ; Kozáková, Zdenka (advisor)
My diploma thesis is focused on a comparison of direct-current and high frequency (15-80 kHz) electric discharge, which generates non-thermal plasma in water solution of sodium chloride. Mainly current-voltage and Lissajous charts are discussed in the first part of this thesis. These charts describe different discharge phases: electrolysis, bubble formation, discharge breakdown and discharge regular operation in a pin-hole of a dielectric barrier. Influence of frequency, electrolyte conductivity, thickness of the diaphragm (or length of the capillary) and pin-hole diameter on discharge breakdown and bubble generation was studied, too. Measurements were realized in a polycarbonate reactor with total volume of 110 ml, which was divided by a changeable polyacetal insulating wall. This wall divided the reactor into two approximately equal spaces with one stainless steel planar electrode in each part. The Shapal-MTM ceramic discs (thickness of 0.3–1.5 mm and diameter of the central pin-hole of 0.3-0.9 mm) were mounted in the centre of the insulating wall. Initial conductivity of sodium chloride solution was chosen within the interval of 100900 S/cm. The second part of my thesis compares an influence of the direct-current (DC) and high frequency (HF) power sources on physical solution properties (conductivity, pH and temperature) and generation of hydrogen peroxide. A plasma reactor with total volume of 4 l and with mixing set up was divided into two equal spaces with one planar platinum electrode in each part. Diaphragm with thickness of 0.6 mm and pin-hole diameter of 0.6 mm was installed in the middle of the separating wall. Experiment was held at discharge operation of 45 W for 40 minutes with both power sources. Detection of hydrogen peroxide was realised by using a titanium reagent forming a yellow complex, which was analysed by absorption spectroscopy. If HF discharge power is plotted as a function of applied frequency, exponential decrease of frequency with increasing power can be observed. Higher breakdown voltage is necessary for thicker dielectric barriers, on the other hand for bigger diameter of the pin-hole lower breakdown voltage and higher power is needed in DC as well as in HF regime. Breakdown voltage is decreased by the increasing conductivity in both regimes; due to more charge carriers in the higher conductivity lower breakdown voltage is needed. However frequency in HF regime and DC discharge power increases. HF discharge power is decreased by the increasing conductivity. Solution conductivity and temperature are increased by initial conductivity value in both discharge regimes. Solution pH drops to acidic conditions when HF or DC positive regime is applied due to the generation of reactive species and electrolysis (in DC regime). However solution becomes alkaline when DC negative regime is applied. Concentration of hydrogen peroxide is produced linearly when HF or DC negative regime is applied and it depends on initial solution conductivity.
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Low Energy Nuclear Reactions
Paták, Roman ; Kaplan, Zdeněk (referee) ; Píštěk, Václav (advisor)
This bachelor thesis deals with collection and arrangement of information about cold fusion. The introduction describes discovery of the cold fusion, problems associated with it and the response of the scientific community. Furthermore, there are explained the assumed basic conditions of its emergence and some of the experiments are detailly described. Finally, the possible direction of the cold fusion utilization in the future is easily outlined.
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Analysis of usage hydrogen in power supply
Krček, Martin ; Ptáček, Michal (referee) ; Radil, Lukáš (advisor)
The work deals with harnessing the hydrogen in electricity production. It surveys hydrogen production, storage, transportation and its use as power source for fuel cells and combustion turbines. Characteristics of a hydrogen production electrolyzer were gauged in laboratory and its efficiency was evaluated.
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Galvanizing of steel components
Turkovič, Matúš ; Hanusová, Petra (referee) ; Zelený, Martin (advisor)
This thesis deals with galvanic, i.e. electrochemical plating. It is concerned with chemical and physical principles that accompanying plating followed by general overview of metal coatings as well as describes the process of their application. In detail, it is focused on nickel coatings. Part of the work is focused also on practical deposition of such coatings on steel samples as well as on study of effects of plating conditions on prepared coatings.
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Hydrogen fuels
Tyagunova, Victoria ; Bébar, Ladislav (referee) ; Jícha, Jaroslav (advisor)
This thesis presents a basic review of production and use of hydrogen fuels. The main focus of this paper is the use of hydrogen in industry and power engineering. The first part concerns various industrial production technologies. The next section is dedicated to the description of hydrogen use for energy conservation, fuel cells, power plants and combustion engines. it includes the comparison of hydrogen and classic fuels. The final part focuses on the economy and costs of hydrogen production and use. This paper will evaluate hydrogen as a potencial fuel for future and will estimate it’s advantages and disadvantages in comparison with conventional fuels.
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Hydrogen production
Kunický, Ondřej ; Šnajdárek, Ladislav (referee) ; Poláčik, Ján (advisor)
Bachelor thesis deals with the production of hydrogen by electrolysis. The introductory part describes the basic properties of hydrogen, the possibilities of its storage and transport, hydrogen safety, the hydrogen economics, and the impact on the environment. Greater attention is then paid to the current possibilities of using hydrogen and its production from fossil and renewable sources. The next part of this thesis deals with possibilities of increasing the efficiency of electrolysis and the control of its performance. At the end, there is a practical measurement of electrolyser and a calculation of the efficiency of hydrogen production by electrolysis.
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