A numerical model for simulating a dry forward in-situ combustion process in two dimensions, was developed. The primary focus is on the simulation of the compositional changes that take place inside the porous medium during the running of the process. The model allows any number of hydrocarbon components and six others, namely, liquid water, water vapour. oxygen, nitrogen, carbon dioxide, and carbon monoxide. It describes the flow of water. oil, and gas, and includes the gravity and capillary effects. The vapourisation and condensation effects of both hydrocarbons and water enhanced the heat transfer, primarily by conduction and convection, ahead of the combustion front. Equilibrium calculations are performed on the components in both the liquid and vapour phases. The changes in pressure, temperature, and flUid compositions govern the direction of the interphase mass transfer. Heat is generated by two types of reaction, namely, low temperature oxidation and burning of the crude oil. The model allows the movement of a thin burning front inside the burning cell. It is found to give a better temperature profIle. representative of the combustion process. Oxygen mole fraction is calculated throughout the porous medium according to the reaction kinetics. thus no assumption is made regarding the degree of oxygen consumption. The effects of oxygen bypassing caused by the kinetic-limited combustion is therefore represented. A total of 18 components were used in the computer runs. Results show the preferential vapourisation of the lighter components in the vicinity of the high temperature burning front. The lighter components then move towards the producer. faster than do the heavier ones. This segregation produce fuel that is heavier than the original oil. High temperature in the upstream cells causes a reduction in the oil viscosity. which in turn increases its mobility, thus transporting more heat downstream. The rise in temperature in the condensation cell results in a decrease in the rate of water vapour condensation; extending the condensation zone downstream. In the high pf(>ssure run. all the hydrocarbon in the downstream cells condenses. In the burning cell however. both the vapour and the liquid phases are present due to the high front temperature. The vapour phase is richer in the light components while the liqUid is richer in the heavy components.

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A detailed multi-zone thermodynamic simulation has been developed for the direct-injection (DI) diesel engine combustion process. For the purpose of predicting heterogeneous type combustion systems, the model explores the formation of pre-ignition radicals, start of combustion, and eventual heat release. These mechanisms are described based on the current understanding and knowledge of the diesel engine combustion acquired through advanced laser-based diagnostics. Six zones are developed to take into account the surrounding bulk gas, liquid- and vapor-phase fuel, pre-ignition mixing, fuel-rich combustion products as well as the diffusion flame combustion products. A three-step phenomenological soot model and a nitric oxide emission model are applied based on where and when each of these reactions mainly occurs within the diesel fuel jet evolution process. The simulation is completed for a 4.5 liter, inline four-cylinder diesel engine for a range of operating conditions. Specifically, the engine possesses a compression ratio of 16.6, and has a bore and stroke of 106 and 127 mm. The results suggest that the simulation is able to accurately reproduce the fuel jet evolution and heat release process for conventional diesel engine combustion conditions. The soot and nitric oxide models are able to qualitatively predict the effects of various engine parameters on the engine-out emissions. In particular, the detailed thermodynamics and characteristics with respect to the combustion and emission formation processes are investigated for different engine speed/loads, injection pressures and timings, and EGR levels. The local thermodynamic properties and energy, mass distributions obtained from the simulation offer some fundamental insights into heterogeneous type combustion systems. The current work provides opportunities to better study and understand the diesel engine combustion and emission formation mechanisms for conventional diesel engine combustion modes. The flexible, low computational cost features of this simulation result in a convenient tool for conducting parametric studies, and benefits for engine control and diagnostics.

In the case of fires frequently wide range of inhomogeneous material is burnt. A lot of combustion products arise during this event, which may adversely affect the environment. Most often detected compounds are carbon dioxide, carbon monoxide, sulfur dioxide, sulphane, hydrogen cyanide, nitrous gases and also organic compounds, which show adverse effects for organism. It is possible to identify and quantify most of them by chemical analysis, but their impact on the ecosystem is not predictable on the basis of these results. An effective tool to predict the impact of combustion products on the ecosystem are ecotoxicity tests. In this thesis, the water leachates of samples from fire places were prepared and subjected to ecotoxicological tests. Two alternative test of ecotoxicity on aquatic organisms were used: the first on the organism Thamnocephalus platyurus (ThamnotoxkitFTM) and the second on the organism Daphnia magna (DaphtoxkitFTM). Another testing aquatic organism was Artemia salina. Ecotoxicity was also tested using a standard phytotoxicity tests; white mustard (Sinapis alba) and white onion (Allium cepa) root growth inhibition tests and lesser duckweed (Lemna minor) growth inhibition test. On the basis of obtained ecotoxicological values LC (EC, IC)50 the impact of matrices from fire places on the ecosystem was evaulated.

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This master thesis focuses on the testing of the combustion equipment and the wood fuel combustion process. The aim of the thesis is to get acquainted with this issue and to analyze solutions for monitoring and control of heat source parameters according to valid legislation. The result of this thesis is the realization and verification of the software design of the combustion test system using the NI LabVIEW development environment.

The subject of the diploma thesis is research of the testing process exhaust clamps. There is a description of a testing device designed to provide simulations of the real operating conditions on an exhaust assembly. The testing device is named the Hot Gas Test Bench. The thesis solves the optimization process of the test setup by determining the optimal fuel ratio, which is given by air flow as oxidizer and flow of natural gas as fuel. The input parameters which provide flow of mentioned fluids are speeds of blowers. In diploma thesis is created a design of initialization and control process to ensure the optional combustion ratio during the entire length of the test.

The scope of this dissertation work is a description of modern methods of reducing exhaust emission in diesel engines. The fundamental part is the application of these methods for diesel engines for off-road use that means for engines that are used in tractors and road machines. The mentioned evidence for the practical utility of the results of this dissertation thesis in practice and their verification on the actual engine are given in the conclusion.

Erdöl und Erdgas liegen als flüssige Kohlenwasserstoffe in porösen Sedimentgesteinen im geologischen Untergrund vor. Um diese Kohlenwasserstoffe zu gewinnen, wird der Untergrund durch Tiefbohrungen zur Förderung erschlossen. Anschließend erfolgt die Förderung des Erdöls in drei Phasen: der Primär-, Sekundär- und Tertiärförderung. In der primären Phase wird Erdöl durch den Druck in der Lagerstätte gewonnen, in der sekundären Phase durch künstliche Aufrechterhaltung des Drucks und in der tertiären Phase durch technische Beeinflussung der strömungsmechanischen und thermodynamischen Eigenschaften des Erdöls. Dennoch verbleibt insbesondere bei Schweröllagerstätten ein Anteil von 45 bis 90 % des ursprünglich in der Lagerstätte vorhandenen Erdöls in der Lagerstätte. Aufgrund strömungsmechanischer und thermodynamischer Einschränkungen ist eine Gewinnung dieses Anteils technisch und/oder wirtschaftlich nicht möglich. Meist wird die Lagerstätte nach Abschluss der Förderung verfüllt und die übertägigen Anlagen zurückgebaut. Zugleich steigt weltweit der Bedarf an Energiequellen, insbesondere an solchen, die für die Dekarbonisierung und Umstellung auf umweltschonende Energien benötigt werden. Wasserstoff wird voraussichtlich als chemischer Energieträger der zukünftige Schlüsselrohstoff für die Energiewende sein. Diese Forschungsarbeit untersucht die Weiternutzung bzw. Erschließung ausgeförderter Erdöllagerstätten zur Wasserstoffgewinnungmittels thermischer Verfahren. Diese Verfahren orientieren sich an bereits etablierten Methoden für die übertägige Verfahrenstechnik. Durch das Verfahren wird die Lagerstätte mithilfe der Verbrennung des in dieser vorhandenen Restöls erhitzt und das entstehende Koks durch eine Wasserinjektion in Synthesegas umzuwandeln. Durch die hohen Temperaturen entsteht in der Lagerstätte eine Atmosphäre aus Wasserdampf, die zur Vergasung des Kokses führt. Das Gas wird durch die Wasserfront aus der Lagerstätte in die Produktionsbohrungen verdrängt und kann anschließend an der Oberfläche aufbereitet werden. Im Kontext der Lagerstättenprozesse entsteht nicht nur Wasserstoff, sondern auch weitere Verbrennungsprodukte wie Kohlenstoffmonoxid, Kohlenstoffdioxid, Sauergase und Kohlenwasserstoffgase. Diese werden verfahrenstechnisch aufbereitet und dampfreformiert in den obertägigen Anlagen. Zur Erfüllung der Anforderungen an blauen Wasserstoff ist die Reinjektion von Kohlenstoffdioxid erforderlich. In der Dissertation wird ein numerisches Berechnungsschema eingeführt und ausführlich getestet, um die lagerstättentechnische Simulation der thermischen Wasserstoffgewinnung durchzuführen. Anhand von Modelllagerstätten werden mithilfe dieses Schemas relevante Prozessparameter ermittelt und für die Übertragung auf die konkrete Lagerstättensimulation aufbereitet. Das Verfahren zur Wasserstoffförderung wird an einer antiklinalen Lagerstätte mit geostatistischer Heterogenität simuliert. Die Ergebnisse werden zur weiteren Auswertung bezüglich Integritätsfragen, Übertageanlagen sowie wirtschaftlicher und strategischer Aspekte herangezogen.