This research work characterises diesel engine soot physiochemical properties and engine performance and emissions for the combustion of two common mineral diesel fuels (low and medium sulphur) and a RME B100 biodiesel fuel at two geometric compression ratios (19.5:1 and 16.5:1) and a broad range of EGR (10 to 55%) for an otherwise unmodified VW 1.9TDI 130PS engine. The principal focus of the research is the physiochemical characterisation of soot sampled from the engine exhaust manifold and also a DPF in the exhaust and exploring how the fuel type, compression ratio and EGR influence the soot properties and how these properties then influence the evolution of the soot in the exhaust.

Particulate number (PN) standards in current and future emissions legislation pose a challenge for designers and calibrators during the warm-up phases of cold direct injection spark ignition (DISI) engines. To achieve catalyst light-off conditions in the shortest time, engine strategies are often employed that inherently use more fuel to attain higher exhaust temperatures. These can lead to the generation of locally fuel-rich regions within the combustion chamber and hence the formation and emission of particulates. To meet these emissions requirements, further understanding of the DISI in-cylinder processes during cold-start are required. This thesis investigates the effect of cooling an optical research engine to temperatures as low as -7°C, one of the legislative test conditions. A high-speed 9 kHz optical investigation of the in-cylinder combustion and fuel spray along with in-cylinder pressure measurements was completed with the engine motored and fired at 1500 rpm during combustion conditions that were essentially homogeneous and stoichiometric. Results showed significant differences between the flame growth structures at various operating temperature conditions with the notable presence of fuel-rich regions, which are understood to be prominent areas of particulate formation. Measured engine performance parameters such as indicated mean effective pressure (IMEP) and mass fraction burned (MFB) times correlated with the observed differences in combustion characteristics and flame growth speed. It was shown that flash boiling of the fuel spray was present in the fully heated engine case and significantly reduced the penetration of the spray plume and the likelihood of piston crown and cylinder liner impingement. The flow and combustion processes of a transient production cold start-up strategy were analysed using high-speed particle image velocimetry (HSPIV). Results highlighted a broad range of flame structures and contrasting flame stoichiometry occurring at different times in the start-up process. Turbulent flow structures were identified that have an effect on the fuel spray development and combustion process as well as providing a path for cold-start emissions reduction. PN and transient hydrocarbon (HC) emissions were measured at cold conditions to further elucidate the effect of operating temperature and correlate emissions data with in-cylinder measurements. A clear link between the quantity and size range of particulate and HC emissions and operating temperature was shown and the precise in-cylinder location of HC emissions, caused by fuel impingement, was inferred from the HC emissions data.

Les explosions de mélanges de gaz inflammables/solides combustibles ne sont pas bien comprises en raison de la complexité des transferts thermiques, des mécanismes de cinétiques et des interactions entre la turbulence /combustion. L'objectif principal de ce travail est d'étudier la sévérité des explosions des nanoparticules de carbone noir/méthane afin de comprendre l'influence de l'insertion des nanoparticules sur les explosions de gaz. Des tests ont été effectués sur ces mélanges dans un tube de propagation de la flamme et dans une sphère d'explosion standard de 20 L. L'influence de la turbulence initiale et de la taille de particule élémentaire du noir de carbone a également été étudiée. Il semble que l'insertion de nanoparticules de noir de carbone augmente d'environ 10% la sévérité de l’explosion pour les mélanges pauvres en méthane. Par conséquent, il semble que les nanoparticules ont un impact sur la sévérité de l'explosion même pour les systèmes à basse turbulence, contrairement aux systèmes impliquant des poudres de taille micrométrique qui nécessitent une dispersion à des niveaux élevés de turbulence. L'augmentation de la vitesse maximale de montée en pression est plus élevée pour des poudres avec un petit diamètre de particule, notamment en raison des phénomènes de fragmentation. En outre, un modèle numérique de propagation de front de flamme associé à un mélange gaz/noir de carbone a été développé pour examiner l'influence du noir de carbone sur la propagation de la flamme. Les résultats du modèle numérique suggèrent que la contribution de la chaleur radiative favorise l'accélération de la flamme. Ces résultats sont en accord avec les résultats expérimentaux de sévérité de l'explosion pour certains mélanges hybrides / Flammable gas/solid hybrid mixture explosions are not well understood because of the interaction of the thermal transfer process, the combustion kinetics mechanisms and the interactions between turbulence and combustion. The main objective on this work is to study the explosion severity and flame burning velocities of carbon black nanoparticles/methane to better understand the influence of added nanopowders in gas explosions. Tests have been performed in a flame propagation tube and in the standard 20 L explosion sphere. The influence of carbon black particles on the explosions severity and in the front flame propagation has been appreciated by comparing the results obtained for pure gas mixtures. It appeared that the carbon black nanoparticles insertion increases around 10% the explosion severity for lean methane mixtures. Therefore, it seems that nanoparticles has an impact on the severity of the explosion even for quiescent systems, contrary to systems involving micro-sized powders that requires a dispersion at high turbulence levels. The increment on the maximum rate of pressure rise is higher for powders with lower elementary particle diameter, which is notably due to the fragmentation phenomena. A flame propagation numerical model associated to a gas/carbon black mixture has been developed to examine the influence of carbon blacks on the flame propagation. The results of the numerical model suggest that the radiative heat contribution promotes the flame acceleration. This result is consistent with the experimental increase on the explosion severity for some hybrid mixtures

Este trabalho analisa os efeitos da transferência de calor por radiação térmica em uma chama laminar resultante da combustão de metano com ar. No processo, são resolvidas as equações da continuidade, da quantidade de movimento, da conservação das espécies químicas e da energia. Ainda é utilizado um modelo de formação de fuligem a duas equações e o modelo de combustão de Arrhenius considerando um mecanismo com 112 reações químicas. Para avaliar os efeitos da radiação térmica, o divergente do fluxo radiante é calculado considerando quatro modelos diferentes para os gases: o modelo do gás cinza, a soma ponderada de gases cinzas, e os métodos SLW e CW. Nessa modelagem, é considerado um meio participante composto por monóxido de carbono, dióxido de carbono, vapor d’água e fuligem. No modelo do gás cinza e da soma ponderada de gases cinzas, o coeficiente de absorção da mistura é obtido por correlações que consideram a temperatura local e a concentração do meio. Nos modelos SLW e CW, o coeficiente de absorção é calculado baseado no banco de dados HITEMP. Assim, primeiramente os resultados do divergente do fluxo radiante são confrontados com os diferentes modelos considerando campos pré-estabelecidos de temperatura e concentrações da mistura de gases com a presença de fuligem e, em seguida, é feita uma análise da influência da radiação considerando uma chama difusa oriunda do processo de combustão de metano com ar. Apesar de o meio analisado ser opticamente fino, situação em que os efeitos da absorção são muito baixos, os resultados encontrados para o divergente do fluxo radiante com os modelos de radiação usados na pesquisa mostraram uma diferença média de aproximadamente 20% entre os modelos, chegando a uma diferença máxima local de mais de 50% quando foi considerado o modelo WSGG. Por outro lado, nas situações em que é considerado todo o processo de combustão, a diferença maior ocorre na comparação de casos em que a radiação térmica é negligenciada com os casos em que a radiação é considerada. Os efeitos causados entre os diferentes modelos de radiação no campo de temperaturas e concentrações dos gases foram pequenos. Assim, é observado que, mesmo em meios opticamente finos, a modelagem da radiação térmica é necessária, pois causa diferenças significativas nos resultados e que nesse tipo de meio não é necessário o uso de modelos mais sofisticados de radiação, pois os efeitos da absorção dos gases é muito pequeno. / This work analyses the effects of thermal radiation heat transfer on methane-air laminar diffusion flames. The analysis is based on the solution of the equations of continuity, fluid motion, species mass-fraction and enthalpy. The soot formation is accounted with a twoequation model while a chemistry mecanism with 112 reactions is used for the combustion of methane. To evaluate the effects of thermal radiation, the divergence of the radiative heat flux is calculated based on four different gas models: the gray gas, the weighted sum of gray gases, the SLW and the CW model. In the modeling, it is considered a participating media composed of carbon monoxide, carbon dioxide, water vapor and soot. Both in the gray gas model and in the weighted sum of gray gases model, the absorption coefficient of the mixture is obtained by correlations that depend on the local temperature and concentration of the medium. On the other hand, in the SLW and CW models, the absorption coefficient is calculated based on the HITEMP spectral database. Thus, the results of the divergence of the radiative heat flux are compared with the different gas models based on a temperature and concentration fields previously obtained, and then, the four gas models used are considered in the entire combustion process to verify the influence of the radiation heat transfer. The results obtained for the divergence of the radiative heat flux considering the four different radiation models used showed an avereged difference of 20%, with a maximum local difference of more than 50%, when the WSGG model was considered. On the other hand, in situations where the whole combustion process is considered, the major difference occurs when is compared the results obtained with a radiation model and the ones where it is neglected. The effects observed with the different radiation models in the temperature field and the gas concentrations were small. Thus is observed that, even in optically thin media, the thermal radiation gas modeling is necessary, and in this particular kind of media, the use of sofisticated gas models are not necessary, because the absorption effect fo the gases are small when compared with their emission.

Sérios problemas ambientais têm origem em processos de combustão incompletos. Entre os produtos indesejados está a fuligem, considerada como um dos principais fatores da mudança climática observada nos último anos. Desta forma, ferramentas para diagnóstico da emissão de material particulado se fazem necessárias. Com o advento do laser, o desenvolvimento de técnicas óticas não intrusivas teve início. Dentre elas, destaca-se a técnica denominada incandescência induzida por laser (laser induced incandescence – LII), a qual pode gerar resultados resolvidos no espaço para a fração volumétrica de fuligem. Neste contexto, este trabalho apresenta um estudo experimental sobre a produção de fuligem em duas situações: na primeira, foram estudadas chamas laminares pré-misturadas de etileno e ar aplicando-se a técnica LII. Os resultados foram calibrados a partir da fração volumétrica de fuligem média empregando a técnica de extinção de luz, obtendo-se, então, resultados quantitativos espacialmente resolvidos da fração volumétrica de fuligem. A utilização de diferentes gases no escoamento anular também foi avaliada. A segunda situação abordada envolve o estudo de chamas laminares não pré-misturadas utilizando o gás natural como combustível. O impacto da diluição de inertes em diferentes proporções sobre a fração volumétrica de fuligem em diversas alturas da chama foi estudado por meio da técnica LII. Os resultados obtidos foram comparados à outros resultados presentes na literatura e servirão como validação de futuros modelos de formação de fuligem. / Serious environmental problems are assigned to incomplete combustion processes. Among the unwanted products, soot can be related as an important factor of climate changes observed in the last years. Thus, particulate material emissions diagnostic tools are necessary. Due the laser advent, the development of non-intrusive optical techniques was possible. One of the most importante technique is the laser induced incandescence, LII, which can generate spatially and temporally resolved results of soot volume fraction. In this context, an experimental study regarding the soot production was developed in two different situations: in the first one, premixed laminar flames of ethylene and air were investigated by applying the LII technique. The results were calibrated through the average of soot volume fraction results obtained by the light extinction technique. Therefore, it was possible to obtain quantitative results of spatially resolved soot volume fraction. Different gases employment at the annular flow were also evaluated. The second situation studied involves the analysis of natural gas laminar non-premixed flames. The impact of different inert gas dilution ratio on the soot volume fraction at different heights of the flame was evaluated by the LII technique. The results were compared to other authors and will serve as validation for future soot formation models.

Este trabalho analisa os efeitos da transferência de calor por radiação térmica em uma chama laminar resultante da combustão de metano com ar. No processo, são resolvidas as equações da continuidade, da quantidade de movimento, da conservação das espécies químicas e da energia. Ainda é utilizado um modelo de formação de fuligem a duas equações e o modelo de combustão de Arrhenius considerando um mecanismo com 112 reações químicas. Para avaliar os efeitos da radiação térmica, o divergente do fluxo radiante é calculado considerando quatro modelos diferentes para os gases: o modelo do gás cinza, a soma ponderada de gases cinzas, e os métodos SLW e CW. Nessa modelagem, é considerado um meio participante composto por monóxido de carbono, dióxido de carbono, vapor d’água e fuligem. No modelo do gás cinza e da soma ponderada de gases cinzas, o coeficiente de absorção da mistura é obtido por correlações que consideram a temperatura local e a concentração do meio. Nos modelos SLW e CW, o coeficiente de absorção é calculado baseado no banco de dados HITEMP. Assim, primeiramente os resultados do divergente do fluxo radiante são confrontados com os diferentes modelos considerando campos pré-estabelecidos de temperatura e concentrações da mistura de gases com a presença de fuligem e, em seguida, é feita uma análise da influência da radiação considerando uma chama difusa oriunda do processo de combustão de metano com ar. Apesar de o meio analisado ser opticamente fino, situação em que os efeitos da absorção são muito baixos, os resultados encontrados para o divergente do fluxo radiante com os modelos de radiação usados na pesquisa mostraram uma diferença média de aproximadamente 20% entre os modelos, chegando a uma diferença máxima local de mais de 50% quando foi considerado o modelo WSGG. Por outro lado, nas situações em que é considerado todo o processo de combustão, a diferença maior ocorre na comparação de casos em que a radiação térmica é negligenciada com os casos em que a radiação é considerada. Os efeitos causados entre os diferentes modelos de radiação no campo de temperaturas e concentrações dos gases foram pequenos. Assim, é observado que, mesmo em meios opticamente finos, a modelagem da radiação térmica é necessária, pois causa diferenças significativas nos resultados e que nesse tipo de meio não é necessário o uso de modelos mais sofisticados de radiação, pois os efeitos da absorção dos gases é muito pequeno. / This work analyses the effects of thermal radiation heat transfer on methane-air laminar diffusion flames. The analysis is based on the solution of the equations of continuity, fluid motion, species mass-fraction and enthalpy. The soot formation is accounted with a twoequation model while a chemistry mecanism with 112 reactions is used for the combustion of methane. To evaluate the effects of thermal radiation, the divergence of the radiative heat flux is calculated based on four different gas models: the gray gas, the weighted sum of gray gases, the SLW and the CW model. In the modeling, it is considered a participating media composed of carbon monoxide, carbon dioxide, water vapor and soot. Both in the gray gas model and in the weighted sum of gray gases model, the absorption coefficient of the mixture is obtained by correlations that depend on the local temperature and concentration of the medium. On the other hand, in the SLW and CW models, the absorption coefficient is calculated based on the HITEMP spectral database. Thus, the results of the divergence of the radiative heat flux are compared with the different gas models based on a temperature and concentration fields previously obtained, and then, the four gas models used are considered in the entire combustion process to verify the influence of the radiation heat transfer. The results obtained for the divergence of the radiative heat flux considering the four different radiation models used showed an avereged difference of 20%, with a maximum local difference of more than 50%, when the WSGG model was considered. On the other hand, in situations where the whole combustion process is considered, the major difference occurs when is compared the results obtained with a radiation model and the ones where it is neglected. The effects observed with the different radiation models in the temperature field and the gas concentrations were small. Thus is observed that, even in optically thin media, the thermal radiation gas modeling is necessary, and in this particular kind of media, the use of sofisticated gas models are not necessary, because the absorption effect fo the gases are small when compared with their emission.

Les particules de suie émises par les moteurs d'avion influencent le climat en absorbant/diffusant la lumière solaire. Elles agissent aussi comme noyaux glaciogènes dans l’atmosphère en participant à la formation des traînées de condensation et des cirrus artificiels, ce qui augmente la nébulosité et affecte l'équilibre radiatif de l'atmosphère. Dans les zones aéroportuaires, elles contribuent à la dégradation de la qualité de l’air et peuvent affecter la santé humaine. Connaître leurs propriétés physico-chimiques est donc primordial pour évaluer leurs impacts environnementaux, sanitaires et agir pour leur réglementation. Nous avons caractérisé les propriétés physiques et chimiques de suies émises par un turboréacteur SaM146-1S17 alimenté avec du kérosène JET A-1 et fonctionnant à différents régimes, dont le régime de croisière. Des informations précises sur leur morphologie, leur (nano)structure, leur composition/spéciation chimique ont été obtenues par microscopie électronique à transmission (TEM), spectroscopie infra-rouge (FTIR), spectroscopie d'absorption des rayons X (NEXAFS) et photoémission X (XPS). Ces techniques ont également permis de caractériser des suies de laboratoire produites par un générateur commercial (miniCAST, Jing Ltd.) et de montrer qu’il permet de générer de bons analogues des suies aéronautiques. La production de quantités importantes de ces analogues aux propriétés physico-chimiques contrôlées offre de nouvelles perspectives quant à l’étude en laboratoire de la réactivité des suies aéronautiques vis-à-vis des environnements atmosphériques et biologiques, permettant d’améliorer notre compréhension de leurs impacts environnementaux et sanitaires. / Soot particles emitted from aircraft engines influence climate by absorbing and scattering sunlight. They also act as ice condensation nuclei in the atmosphere by participating to the formation of condensation trails and artificial cirrus clouds that increase the cloudiness and affects the radiative balance of the Earth’s atmosphere. In airport areas, they contribute to the degradation of air quality and can affect human health. Knowing their physical and chemical properties is therefore of prime importance to assess their environmental and health impacts as well as acting for their regulation. We have characterized physical and chemical properties of soot emitted by a SaM146-1S17 turbofan engine fueled with kerosene JET A-1 and operated at different regimes, including the cruise regime. Accurate information about their morphology, (nano)structure, chemical composition/speciation have been obtained by transmission electron microscopy (TEM), infrared spectroscopy (FTIR), Near-Edge X-ray Absorption Fine Structure (NEXAFS) and X-Ray Photoelectron Spectroscopy (XPS). These techniques have also been used to characterize laboratory soot produced by a commercial generator (miniCAST, Jing Ltd.) and to show that it can generate relevant analogues of aeronautic soot. The production of large amounts of these analogues with controlled physico-chemical properties offers new prospects for laboratory studies of aeronautic soot’s reactivity with respect to atmospheric and biological environments aiming at improving our understanding of their environmental and health impacts.

Made available in DSpace on 2014-06-11T19:29:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-04-25Bitstream added on 2014-06-13T18:58:33Z : No. of bitstreams: 1 yamanaka_es_me_araiq.pdf: 1186411 bytes, checksum: 0eaad1b837a55ef238caa6cd5300b6eb (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A fuligem proveniente das queimadas de cana-de-açúcar exerce um importante papel na translocação dos HPAs, gerados em processos de combustão incompleta, através dos diversos compartimentos ambientais. Quando trazido até áreas urbanas, o material particulado fino gerado na queima pode provocar problemas respiratórios e carregar consigo os HPAs, dentre os quais há alguns com alto potencial carcinogênico. Tendo em vista o pequeno número de estudos relacionados a HPAs na matriz de fuligem de cana e a utilização de extrações com solventes em praticamente todos esses, o objetivo deste trabalho foi a verificação do comportamento térmico dos HPAs prioritários da US-EPA, adsorvidos em fuligem de cana, frente a um programa de aquecimento controlado, no intuito de obter informações para a implementação e otimização de um sistema de dessorção térmica para extração dessas substâncias. Foram aplicadas as técnicas de termogravimetria (TG), análise térmica diferencial (DTA) e calorímetria exploratória diferencial (DSC) a amostras de: padrões de 16 HPAs isolados; fuligem de cana fortificada com cada um destes padrões; fuligem fortificada com todos os 16 padrões simultaneamente (amostra composta); material de referência certificado SRM 1649a da NIST e finalmente, uma amostra de material particulado atmosférico obtida na cidade de Araraquara, São Paulo. Foram obtidas as temperaturas de fusão e sublimação dos padrões isolados, além das faixas de temperatura que acompanham suas perdas de massa, que variaram de 70 a 380 ºC. No estudo da adsorção na matriz, foi observado que esta contribui para um padrão de perda de massa mais homogêneo e difuso, sugerindo uma possível interação, entretanto sem modificar o intervalo de vaporização/sublimação dos HPAs... / The soot originated from the sugar cane burning plays an important role in the translocation of PAHs, generated in incomplete combustion processes, through multiple environmental compartments. When brought to urban areas, fine particulate matter generated in the burning can cause respiratory problems and carry PAHs, among which are some with high carcinogenic potential. Given the small number of studies related to PAHs in the sugar cane soot matrix and the use of solvent extraction in almost all of these, the aim of this paper was to check the thermal behavior of de US-EPA priority PAHs, adsorbed on sugar cane soot and subjected to a controlled heating program, in order to get information for the implementation and optimization of a thermal desorption system for the extraction of these substances. Thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC) techniques were applied to samples of: 16 US-EPA PAH standards, individually; sugar cane soot fortified with each of these standards; soot spiked with all 16 standards simultaneously (composite sample); NIST Standard Reference Material 1649a (urban dust); and finally, an airborne particulate matter sample, obtained in the city of Araraquara, Sao Paulo, Brazil. Melting and vaporization/sublimation temperatures of the isolated standards were obtained, together with the temperature ranges that accompany their mass loss, which varied from 70 to 380 ºC. In the study of matrix adsorption, it was observed that it contributes to a more homogeneous and diffuse mass loss, suggesting a possible interaction with the PAHs, however without modifying the range of vaporization/sublimation of adsorbed PAHs. The comparison of the composite sample with SRM 1649a and airborne particulate matter brought certain... (Complete abstract click electronic access below)

Sérios problemas ambientais têm origem em processos de combustão incompletos. Entre os produtos indesejados está a fuligem, considerada como um dos principais fatores da mudança climática observada nos último anos. Desta forma, ferramentas para diagnóstico da emissão de material particulado se fazem necessárias. Com o advento do laser, o desenvolvimento de técnicas óticas não intrusivas teve início. Dentre elas, destaca-se a técnica denominada incandescência induzida por laser (laser induced incandescence – LII), a qual pode gerar resultados resolvidos no espaço para a fração volumétrica de fuligem. Neste contexto, este trabalho apresenta um estudo experimental sobre a produção de fuligem em duas situações: na primeira, foram estudadas chamas laminares pré-misturadas de etileno e ar aplicando-se a técnica LII. Os resultados foram calibrados a partir da fração volumétrica de fuligem média empregando a técnica de extinção de luz, obtendo-se, então, resultados quantitativos espacialmente resolvidos da fração volumétrica de fuligem. A utilização de diferentes gases no escoamento anular também foi avaliada. A segunda situação abordada envolve o estudo de chamas laminares não pré-misturadas utilizando o gás natural como combustível. O impacto da diluição de inertes em diferentes proporções sobre a fração volumétrica de fuligem em diversas alturas da chama foi estudado por meio da técnica LII. Os resultados obtidos foram comparados à outros resultados presentes na literatura e servirão como validação de futuros modelos de formação de fuligem. / Serious environmental problems are assigned to incomplete combustion processes. Among the unwanted products, soot can be related as an important factor of climate changes observed in the last years. Thus, particulate material emissions diagnostic tools are necessary. Due the laser advent, the development of non-intrusive optical techniques was possible. One of the most importante technique is the laser induced incandescence, LII, which can generate spatially and temporally resolved results of soot volume fraction. In this context, an experimental study regarding the soot production was developed in two different situations: in the first one, premixed laminar flames of ethylene and air were investigated by applying the LII technique. The results were calibrated through the average of soot volume fraction results obtained by the light extinction technique. Therefore, it was possible to obtain quantitative results of spatially resolved soot volume fraction. Different gases employment at the annular flow were also evaluated. The second situation studied involves the analysis of natural gas laminar non-premixed flames. The impact of different inert gas dilution ratio on the soot volume fraction at different heights of the flame was evaluated by the LII technique. The results were compared to other authors and will serve as validation for future soot formation models.

Pour concevoir des foyers aéronautiques plus fiables et moins polluants, les industriels ont de plus en plus recours à des simulations numériques s’appuyant sur de nombreux modèles physiques. Si l’on s’intéresse en particulier aux problématiques des charges thermiques pariétales et des émissions polluantes, la modélisation des phénomènes couplés de combustion, de formation des suies et de transfert radiatif est nécessaire. Ainsi, cette thèse a pour objectif de développer une méthodologie permettant de simuler ces phénomènes couplés de manière instationnaire, dans un foyer représentatif des systèmes industriels. Un modèle de formation des suies simple et robuste, à caractère empirique, a d’abord été mis au point sur une configuration de flamme 1D laminaire prémélangée. Ce modèle a été choisi car, étant compatible avec des mécanismes réactionnels globaux, il est bien adapté aux simulations instationnaires en géométrie complexe. Dans un deuxième temps, il a été appliqué à la simulation instationnaire de l’écoulement turbulent réactif diphasique dans un foyer doté d’un prototype d’injecteur industriel. Les niveaux de température obtenus ainsi que la topologie du champ de fraction volumique de suies ont été comparés aux résultats expérimentaux. Les écarts constatés ont été analysés et des corrections ont été proposées. Enfin, une stratégie de couplage entre l’approche LES (Large Eddy Simulation) et un outil de simulation des transferts radiatifs basé sur la méthode de Monte Carlo a été mise au point et éprouvée sur le foyer étudié. L’écoulement apparaît peu affecté par le rayonnement, mais en revanche, les transferts radiatifs ont un impact relativement important sur les flux reçus par les parois / Numerical simulations, involving numerous physical models, are more and more employed to design more reliable and less pollutant industrial combustors. In particular, focusing on wall thermal load and pollutant emission issues, coupled phenomena such as combustion, soot formation and radiative transfer have to be modelled. Thus, the aim of this PhD thesis is to develop a methodology to simulate these coupled phenomena in an unsteady way, in an industrial-like combustion chamber. A simple and robust empirical soot formation model has been developed and applied in a first step to a 1D laminar premixed flame configuration. This model was chosen because it is well adapted to unsteady simulations in complex geometries, as it is compatible with global reaction mechanisms. In a second step it was applied to the unsteady simulation of the two-phase turbulent reactive flow in a combustor equipped with an industrial injector prototype. Predicted temperature levels and topology of the soot volume fraction field were compared to experimental results. Some discrepancies were observed: they were analysed and corrections were proposed. Finally, a coupling strategy between the LES (Large Eddy Simulation) approach and a radiative transfer simulation tool based on the Monte Carlo method was developed and tested on the same combustor. It appears that radiative transfer does not greatly modify the flow, but has a relatively important effect on wall heat fluxes.