[pt] O desenvolvimento de um motor de quatro tempos, de ignição por centelha, com injeção direta de combustível dentro da câmara de combustão foi uma iniciativa importante para o mercado automobilístico mundial. O potencial termodinâmico deste tipo de motor e sua notória melhoria na economia de combustível têm feito com que a tecnologia seja foco de um grande número de projetos de pesquisa, com o objetivo de entender, desenvolver e aperfeiçoar o sistema de injeção direta de combustível. No entanto, para atender aos novos limites de emissões estabelecidas pela especificação EURO 5, foi necessária uma reavaliação do projeto da geometria do injetor, o que ocasionou no desenvolvimento de um novo componente com um maior número de furos e com uma redução do diâmetro dos mesmos (injetor multifuros). Essa alteração no projeto visa garantir uma melhor pulverização, otimização da relação ar/combustível e, consequentemente, um melhor processo de queima na câmara de combustão, atendendo dessa forma os limites de emissões estabelecidos pela diretriz normativa vigente. Os processos de preparação da mistura, injeção, vaporização e controle do escoamento de ar dentro do cilindro têm sido as principais fontes de publicações de periódicos que estudam o sistema de injeção direta. O presente trabalho, por sua vez, tem por finalidade avaliar a formação de depósitos de compostos inorgânicos nos injetores, provenientes da utilização de combustíveis formulados com diferentes teores de sulfato. O motor utilizado para execução dos testes foi o EP6CDT da PSA Peugeot Citroen. No estudo foram realizados ensaios em bancada de testes e em veículos (estrada e dinamômetro). Outros veículos com a mesma tecnologia, disponíveis no mercado brasileiro, também foram testados. As variáveis avaliadas durante o projeto foram: a composição química de diferentes combustíveis, fator de correção do tempo de injeção (FRA) e a vazão através dos bicos injetores no decorrer dos testes. Os estudos indicaram que a mudança na geometria dos injetores, somada a composição das gasolinas nacionais testadas, originou a formação dos depósitos que será discutida ao longo deste trabalho. / [en] The development of a four-stroke engine, spark ignition, with direct injection of fuel into the combustion chamber was an important initiative for the global automotive market. The thermodynamic potential of this type of engine and its significant improvement in fuel economy have meant this technology as focus of a large number of research projects, with the objective to understand, develop and improve the system of direct fuel injection. However, to meet new emission limits set by Euro 5 specification, it was necessary to reevaluate the geometry design of the injector, which resulted in the development of a new component with a larger number of holes and with a diameter reduction (multi-holes injector). This change in the project aims to ensure a better spray, optimizing air / fuel ratio and, consequently, a better process of combustion inside the combustion chamber, satisfying the emission limits established by the applicable norms. The processes for preparing the mixture, injection, atomization and air flow control inside the cylinder have been the main source of periodic publications that study the direct injection system. Therefore, this paper purpose is to evaluate the formation of inorganic deposits in the injectors using fuels formulated with different amounts of sulfate. The engine used for running the tests was the EP6CDT of PSA Peugeot Citroen. For this study one has performed tests on test bench and in vehicles (road and dynamometer). Other vehicles, with the same technology available in Brazil, were also tested. The variables evaluated during the project were: the chemical composition of different fuels, the correction factor from the injection time (FRA) and flow through the injectors during the tests. This study has indicated that the injector geometry modification, coupled with tested compositions of gasoline, resulted in the formation of deposits that will be discussed throughout this work.

L'impact des particules fines (PM10-PM2.5) sur la santé a été largement étudié depuis de nombreuses années, notamment pour les sites de proximité automobile. De nombreux dépassements de la valeur limite en PM10 imposée par les directives européennes ont lieu en France et en Europe, en milieu urbain et plus fréquemment en proximité automobile. Les émissions véhiculaires sont une des sources majeures de particules. Ces émissions proviennent à la fois des échappements (TE) mais aussi des émissions hors échappement (TNE) (abrasion des freins, des pneus et de la route, resuspension des poussières de la chaussée dû au déplacement des véhicules…). En France, très peu d'études en proximité automobile ont été effectuées. Les études de déconvolution des sources en France et en Europe s'appuient la plupart du temps sur des parcs automobiles non adaptés (parc américain) ou trop anciens. De plus, seule la source TE est considérée, ce qui sous-estime largement la contribution véhiculaire aux PM10. La meilleure connaissance de la formation, de la caractérisation et de la quantification des particules émises par le trafic est devenue primordiale. L'objectif final étant la détermination des contributions des émissions véhiculaires TE et TNE aux sources primaires de particules, la caractérisation précise de ces sources est primordial. Pour cela, la recherche de traceurs véhiculaires en phases gaz et particulaire a constitué une grosse partie de ce travail. La combinaison de l'étude sur banc à rouleau de cinq véhicules bien représentés dans le parc automobile roulant français et de l'étude effectuée en proximité automobile (Rocade Sud de Grenoble) a constitué le socle de ce travail. Dans la première étude, certains composés chimiques sont apparus comme indicateurs des émissions TE (EC, HAP légers, profils d'alcanes typiques, quelques métaux comme Fe, Cu etc.). Des différences importantes sont observées entre les véhicules diesel sans filtre à particules (FAP) et les véhicules essence et diesel sans FAP. La seconde étude, comparant le site trafic (Grenoble-Echirolles) avec un site de fond urbain (Grenoble- Les Frênes), a mis en évidence certains composés chimiques comme spécifiques des sources TNE et TE sur la base des connaissances acquises avec les mesures sur banc et sur l'enrichissement de certains composés par rapport au site de fond (EC, Cu, Fe, Sn, Mn…). On peut souligner certains enrichissements majeurs comme EC (78%), Cu (82%), Fe (88%), etc. La résolution temporelle a été faite sur une base de 4h, permettant ainsi une caractérisation chimique détaillée en fonction des heures de pointe et "creuses". Une troisième étude, en site trafic également (Grenoble-Le Rondeau) mais sous influence du salage en hiver, est venue compléter nos recherches. Enfin, en nous appuyant sur les résultats de la première partie, nous avons cherché à déconvoluer les sources véhiculaires TE et TNE (Echirolles et Le Rondeau) au moyen d'un modèle statistique d'analyses multivariées, la PMF (Positive Matrix Factorization), apportant ainsi la contribution possible de ces sources aux PM10. Les émissions véhiculaires (TNE+ TE) y contribuent à 34% à Echirolles et à 53% au Rondeau. Quelques incertitudes sont discutées par rapport aux résultats trouvés avec ceux provenant de l'étude géochimique détaillée en première partie. / Fine particles (PM10-P2.5) are recognized to be deleterious to human health particularly in the roadway vicinity. In European countries, and in particular in France, the European daily limit value is exceeded in many sites more than 35 times a year. One of the major sources of fine particles in urban and roadside sites is road traffic. Emissions from road traffic involve exhaust and non-exhaust emissions (resuspension of road dusts, from the brakes, tyres and road-surface-wear, from the corrosion of vehicle components…). Numerous studies have been performed in order to account for exhaust emissions, however not in France. Generally, the profiles used in source apportionment models are not adapted (since they are American profiles) to the French or European fleets. In addition, the contribution of the nonexhaust fraction to total particulate matter (PM) mass is generally not accounted for in the source apportionment results. Therefore, PM10 emissions are underestimated. As a result, better knowledge about formation, characterization and quantification of particles from traffic are becoming necessary. The goals of this work are numerous because ambient air and exhaust emission measurements have been involved. The aim is to accurately discriminate exhaust and nonexhaust sources, in order to provide groundbreaking insights into the contribution and chemical composition of traffic sources. Therefore, the analyses of gas and particle tracers represent a big part of this work. The relationships between the measurements of 5 in-use vehicles well-represented in the French fleet and measurements performed in the vicinity of a suburban highway (southern ring road of Grenoble) have been firstly examined. In the first study, several chemical compounds, organics and inorganics, appeared as tracers of vehicular exhaust (EC, light PAHs, typical alkanes profiles, metals like Fe, Cu etc.). Large differences are noticeable between Diesel vehicles without DPF and petrol vehicles/diesel vehicle retrofitted with a DPF. In the second study, comparison with results from an urban background site (Grenoble-Les Frênes) and from the traffic site (Grenoble-Echirolles) highlighted several specific chemical compounds of exhaust and non-exhaust sources (EC, Cu, Fe, Sn, Mn…). Large increments due to the local traffic have been observed (EC (+78%), Cu (82%), Fe (88%), etc.). The 4-hour temporal resolution allowed for the detailed characterization of chemical species during rush hours and less busy periods. An additional field campaign was performed in another roadside site (Grenoble-Le Rondeau) but in winter during salting conditions. Supplementary information was obtained concerning non-exhaust sources. Finally, thanks to the results from the first part of this work, a Positive Matrix Factorization (PMF) analysis was applied to roadside data (Echirolles and Le Rondeau) in order to discriminate non-exhaust and exhaust traffic sources and to estimate their contribution to PM10. Major contributions for traffic sources (exhaust and non-exhaust) were 34% (Echirolles) and 53% (Le Rondeau). Uncertainties linked to these results are discussed with the results of the first part (detailed chemical study) of this work.

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