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Exhaust Gas Energy Recuperation in a Commercial Vehicle Diesel Engine
Šroba, Roman ; Janoušek, Michal (referee) ; Vondrák, Adam (advisor)
The scope of this thesis investigates value added by a turbocharger with an associated motor-generator unit to a diesel engine used by a commercial vehicle. A thermodynamic model of the engine was prepared in GT-SUITE software. Case studies were primary focused on a reduction of specific fuel consumption as well as a nitrogen oxides production using an energy recuperation of exhaust gas. Furthermore, there are described potential benefits of using an electric assistance in order to increase an exhaust gas temperature during a steady state engine operation. Additionally, there is an investigation of potential benefits of a turbocharger assistance in a transition engine mode operating during rapid acceleration of the vehicle. The results of individual analysis will be taken into account for a selection of turbocharger regarding specific engine implementation. The results of simulation suggest that it is possible to lower specific fuel consumption, production of nitrogen oxides, as well as accelerate turbocharger response.
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Determination of emissions and harmful particles of exhaust gases of CNG, petrol and diesel vehicles
Rozsíval, Adam ; Libich, Jiří (referee) ; Bača, Petr (advisor)
The thesis deals with an analyses of emission and harmful particles of exhaust fumes of automobiles with an environmental impact. More precisely, it describes the basic characteristics of current fuel types and emission produced by internal combustion engines. Next, it deals with the measures and possibilities of decreasing car traffic emission with respect to environmental impact. It also describes the current European standards for emission and the systems of the cars that are able to decrease emission. The work also deals with the measuring of emission and the methods that are used. According to the measuring methods, the analysis of exhalation is done and it is based on the data of the real car fleet. Values of the emission analyses are compared. The financial aspect is a part of the analyses.
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Reduction of nitrogen oxides in flue gas on special catalysts
Vávra, Jan ; Krejčí, Tomáš (referee) ; Jecha, David (advisor)
The diploma thesis is focused on experimental reduction of nitrogen oxides on special catalysts. The latest and state-of-the-art flue gas cleaning technologies are used. Selective catalytic reduction results in the desired level of pollution. It is necessary to meet the prescribed emission limit. A ceramic honeycomb filter based on vanadium and titanium is used as the catalyst. The entire measurement is carried out on the experimental INTEQ II unit, which is installed in the flue gas cleaning laboratory at NETME Center. It is shown which operating parameters achieve better efficiency of flue gas cleaning. Comparison of the BASF and CERAM catalysts is also performed. Finally, a material balance of the system is performed and a new external electric heater is designed to accelerate the heating process.
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Possibilities of elimination of residual ammonia content from technological water in power plants
Hajzler, Jan ; Bartoníčková, Eva (referee) ; Opravil, Tomáš (advisor)
This master thesis aims to study the possibilities of eliminating, or separation of ammonium shares from technological water of plants, where is introduced a secondary method of flue gas denitrification (SCR, SNCR). The need for elimination of ammonium shares arose after introduction of emission cap, which have been tightened since January 2015. The denitrification technologies were installed on devices that did not comply with the new limits. The theoretical part of the thesis deals with the description of combustion processes, as a fluid, and high temperature combustion of solid fuels, mechanisms of emissions and their reduction options. At the conclusion of the theoretical part is discussed the contents of the ammoniacal nitrogen in waters used in electricity and heating facilities to transport, or from which are separated by solid products of some processes such as desulphurization. There are also discussed some options for removal of ammonium salts from technological waters. Experimental part deals with finding appropriate method of determination of ammoniacal nitrogen, and the possibilities of its elimination by conversion to insoluble compound. Last but not least, the work deals with the evaluation of the sustainability of the proposed solutions. And as well as the real possibilities of their application in practice.
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Reduction of nitrogen oxides from the flue gas stream on catalysts under non-standard conditions
Minář, Marek ; Brummer, Vladimír (referee) ; Jecha, David (advisor)
The objective of the presented diploma thesis is reduction of nitrogen oxides from the flue gas stream on catalyst under non-standart conditions. Emphasis is places on the description of selected pollutants in flue gas (especially nitrogen oxides), legislative requirements for air protection and technologies for removal of nitrogen oxides, expecially methods of selective catalytic and non-catalytic reduction. The practical part is devoted to the reduction of nitrogen oxides by selective catalytic reduction on a pilot plant INTEQ II in the laboratory NETME Center. The subject of interest is the determination of the NOx reduction efficiency depend on the temperature for selected catalyst. The end of the practical part pursues with comparison of measurement results and their evaluation.
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NOx Reduction System
Karafa, Pavel ; Bradávka, Marek (referee) ; Svída, David (advisor)
This diploma thesis deals with the issue of nitrogen oxides emissions in exhaust gases and possibilities of their reduction. The task of the thesis was analysis of systems for NOX reduction by contemporary diesel engines, design and construction of NOX reduction device for given diesel engine, then verify functionality of this system compiled from commercially available components. In the last part of thesis available measurements will be made with an analysis of achieved results.
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Measurement of the photocatalytic efficiency of FN NANO®2 coating on an idealized urban model
Nosek, Štěpán
An experiment was conducted to test the effectiveness of the FN NANO®2 coating in removing a harmful pollutant (NOX) by photocatalysis on a surface in a model of an urban street canyon. The experiment was conducted in a wind tunnel under controlled conditions, simulating two cases of street canyon pollution: from a line source within the canyon and a polluted incoming boundary layer. The results showed that the coating has an average efficiency of 15% when removed from NOX, with the efficiency decreasing with height within the street canyon. The removal efficiency depends on the type of pollution. In the case of the polluted incoming boundary layer, the coating showed very high efficiency in removing NO (average efficiency of 19%) and NO2 (average efficiency of 7%). These results show that both methods can be used to analyse the removal of NOX concentrations by the FN NANO®2 coating in a street canyon.
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Measurement of photocatalytic efficiency of FN NANO®2 coating on Legerova street model
Nosek, Štěpán
An experiment was conducted to test the effectiveness of the FN NANO®2 coating in removing a pollutant (NOX) by photocatalysis on a surface in a model of a real urban street canyon. The experiment was conducted in a wind tunnel under controlled conditions and simulated the case of pollution of a Legerova street model by an upwind boundary layer polluted by NOX concentrations from a car. The results showed that the coating has a higher degradation efficiency for NO (up to 15%) than for NOX (max. 12%), with the efficiency depending on the investigated position. The lowest efficiency was achieved in streets aligned parallel to the upwind boundary layer, which are naturally better ventilated.
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The role of NADPH oxidase and ros in invadopodia formation
Hanušová, Kristýna ; Brábek, Jan (advisor) ; Vrbacký, Marek (referee)
Invadopodia as specific organelles enabling tumour cells movement, spreading over the organism and ultimately formation of metastasis are possible and promising targets of tumour therapy. Recently, many interesting facts about assembly and mechanism of function of invadopodia were discovered. Invadopodia are centres of ECM degradation by extra-cellular proteases facilitating an invasion of tumour cells. For creation of invadopodia a precisely localized increased production of ROS is necessary. ROS work as crucial signalling molecules and participate in many processes resulting in invadopodia formation. ROS in tumour cells are produced by specific extra-mitochondrial NADPH oxidases (Nox). Several regulatory molecules participating in activation and localization of Nox to invadopodia have been discovered recently (Tks organizer proteins). Furthermore, a regulatory role of Src kinase in ROS production and subsequent invadopodia formation was confirmed. Key words: ECM degradation, invadopodia, invasion, proteases, Nox, ROS, Src kinase, Tks proteins
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