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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.
81

Vliv vnitřní recirkulace spalin na charakteristické parametry spalování / The influence of the furnace gas recirculation on characteristic parameters of the combustion process

Macenauerová, Tereza January 2015 (has links)
This thesis deals with the evaluation of emissions of NOx and CO formed during the combustion process when the burner utilizing fuel staging and internal flue gas recirculation is used. In the theoretical part the NOx formation mechanisms and methods used to suppress their formation are described. This is followed with the currently valid legislation in the Czech Republic in terms of the emission limits for NOx and CO in stationary sources. In the work, combustion tests were performed at the burners testing facility at UPEI BUT. The tests revealed that the most important parameters, which influence the NOx formation, are fuel staging, increasing combustion air excess and the utilization of new equipment that induces the flue gas to be drawn back into the burner. The equipment is installed in the burner’s air channel. The dependence of flue gas temperature, heat flux to the combustion chamber’s section walls and in-flame temperatures distribution in the horizontal symmetry plane of the combustion chamber on various parameters were investigated. The parameters included the geometry of the equipment for flue gas recirculation, primary/secondary ratio, geometry of nozzles for secondary fuel supply, tangential orientation of these nozzles towards the burner axis, and the excess of combustion air.
82

Vliv oxidů těžkých kovů na tvorbu a vlastnosti portlandského slínku / Influence of heavy metal oxides on the formation and properties of Portland clinker

Kašpárková, Kateřina January 2016 (has links)
The Master’s thesis is focused on a study of the effect of increased content of heavy metals present in a raw meal on the formation and properties of prepared clinker and acquired cement. Main attention is devoted to changes on the physical, mechanical, microstructural and hydration properties. The theoretical part contains an overview of clinker minerals occurring in Portland cement including the possibility of incorporation of heavy metals into their structure and affecting the properities of the cement. In the experimental part, there is compared the effect of heavy metal oxides on the composition and hydration properties of portland clinker and physical-mechanical and microstructural properities of cement pastes prepared from this clinker.
83

Environmentální zdanění v Evropské unii se zaměřením na automobilový průmysl

Červenková, Pavlína January 2019 (has links)
The diploma thesis focuses on environmental taxation of road motor vehicles in EU countries. Firstly, the thesis deals with negative external effects of transport which are the reason for the existence of the environmental taxes. Secondly, tools used for regulation of negative external effects in the area of environmental protection including environmental tax reform are described. Subsequently, the thesis presents legislation for taxation of road transport in the European Union and analyses the road motor vehicle taxation in the EU member states with regard to environmental aspects. Moreover, the systems of taxation of ownership of road motor vehicles in selected countries of the European Union (Denmark, Italy, Netherlands and Sweden) are described and the levels of taxation of cars and trucks in the Czech Republic and in selected countries of the European Union are compared. The thesis also includes a proposal for taxation of road motor vehicles in the Czech Republic with regard to the environmental impacts of road transport.
84

Provozní účinnosti zdrojů tepla / Operational efficiency of boilers

Doležal, Lukáš January 2019 (has links)
The topic of this diploma thesis is the operational efficiency of heat sources. The work had several goals. The first was to determine the efficiency of the wood boiler according to available calculation methods and to compare the methods among them. The second was to determine the difference in the performance of the flue gas analyzer and the real calculation. Further, to determine the efficiency of a boiler firing different wood species - spruce and hornbeam based on their properties and elemental composition. Experimental measurement of various operating states of effectiveness took place in an older two-generation family house, which was also the subject of the project part. Due to lack of project documentation, it was necessary to focus and plot the object. Afterwards, the building was thermally inspected and the design of the heating system and the reconstruction of the whole heating system was carried out. The project was developed in two variants for two different heat sources - a heat pump and a solid fuel boiler for heating and water preparation. The thesis deals with the technical report, the conceptual solution of the related professions, the evaluation of the heat source variants and the project documentation.
85

Provozní účinnost kotlů / Working efficiency of boilers

Rejsa, Vojtěch January 2020 (has links)
This work deals with the determination of the operational efficiency of solid fules boilers for their inclusion in the relevant emission class according to ČSN EN 303-5. Two steel boilers of the same manufacturer, type and performance but of different ages, were measured. The experimental measurments in the real operation of the boilers were carrien out during the combustion of two types of fuels, namely brown coal and spruce wood.The operational efficiency of the monitored sources was calculated from the measured data using both direct and undirect methods. The found efficiency of the boilers corresponds to the expected values, due to their construction, age and the way of using individual components and regulations. In the project part of this work there is a proposal of heating of the family house for the condition of the building before and after the insulation. The calculation was made for the solid fuel boiler and heat pump. The building is heated by radiators and floor heating. The design of the whole system, technical report and project documentation were prepared for each variant.
86

Vliv zatížení spalovacího motoru na výstupní parametry traktorových souprav / Effect of engine load on the output parameters of the tractor kits

Paulmichl, Roman January 2013 (has links)
The thesis deals with the current situation in the construction of tractors, particularly engines and accessories. The work includes a methodology for measuring tractor rigs in traffic as well as methodology for plough/plow kits measuring. The measured values were tabulated, graphically presented and analysed. The thesis provides an overview of the issue of the combustion engine load placed on the engine by working conditions in transport, during primary soil tillage with different modes of operation of the tractor set. The thesis aim is to find out the practical effect of the engine load on the monitored parameters and to indicate possibilities for achieving higher efficiency in tractor units with minimum fuel performance
87

Analýza radiační kontroly skladu vyhořelého jaderného paliva v JE Temelín / Analysis of radiation control in the storage of spent nuclear fuel at NPP Temelín

PAPAN, Juraj January 2012 (has links)
Problems of dealing with radioactive materials, especially burnt out nuclear fuel, are a delicate and discussed topic in the Czech Republic and other advanced countries nowadays. In this work, the realization of radiation control of warehouse of burnt-out atomic fuel of nuclear power plant Temelín is analysed. Step by step there are stored packaging files filled with burnt-out fuel which is produced by the running of atomic reactors. In the introductory chapters individual packaging files are described. The shielding of stored burnt-out nuclear fuel and prevention of release of radionuclides beyond the protective casing of packaging files depend on their quality. Further the lo-cality of nuclear plant Temelín, where the warehouse of burnt-out nuclear fuel is placed including manipulations which are carried out with the packaging file, is described. The emphasis is placed on monitoring technological parameters during the storage of pack-aging files. The target of this work is to analyse the radiation control of warehouse of burnt-out nuclear fuel, precautions of radiation protection valid for this object and con-sider the possibility of optimalization of used measuring devices, suggest the adjustment of the way of carried out monitoring. For meeting the goals of this works it was neces-sary to carry out monitoring the current radiation situation in the storage boat which is partly filled with packaging spaces when according to the following calculations I ap-proached to the prediction of the level of radiation situation during the maximum filled storage boat. These calculations are at the same time the background for the proposal of adjustment of regime precautions in this object with the aim to optimise the professional radiation. One of the basic strategic targets of the operator of nuclear plant Temelín, company ČEZ a.s., is to ensure a safe operation of the biggest Czech nuclear plant, one of the basic conditions for meeting this target is to ensure the radiation control and pro-tection in the required quality. The results, which are the output of this work, will be given to the department Operation of radiation protection for other practical usage, pos-sible adjustment of a current operation documentation which solves the radiation control of the storage of burnt-out nuclear fuel.
88

Výpočtová studie Millerova cyklu benzínového motoru s turbodmychadlem / Computational Study of the Miller Cycle on a Gasoline Engine with a Turbocharger

Černý, Roman January 2017 (has links)
The scope of this thesis is the Miller engine cycle analysis and its practical application on a turbocharged spark ignited engine. Based on the sensitivity analysis of the limits affecting the ideal Miller cycle thermal efficiency a thermodynamic model of the engine with a prolonged expansion was set up in the GT-POWER software. The results of the analyses were used to evaluate the feasibility of the reference engine conversion for an operation with Miller cycle.
89

Analýza vlivu převodového ústrojí na tahový výkon traktoru / Analysis of powertrain impact on pull power capacity of a tractor

Zicha, Marek January 2017 (has links)
This diploma thesis “Analysis of powertrain impact on pull power capacity of a tractor” is focused on evaluation of measured data gained from performance testing of tractors Claas Arion 640 for two different types of transmission. There are also discussed the measuring methods and there is detailed described the function of measured transmissions.
90

Analýza tepelné spotřeby objektu / Analysis of Heat Energy Consumption of Buildings

Houzar, Tomáš January 2017 (has links)
Master’s thesis is focused on analysis of thermal consumption in the buiding. This work describes current state of family house and possible suggestions for heating and water heating. Part of solution is created program, which supposed to serve as universal calculation program for design and economic evaluation of suggested solar systém and allows a comparison between commonly used sources for heating and water heating.

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