In contradistinction with road transport exhaust particulate matter (PM) emission, non-exhaust PM emission has not decreased substantially in recent years. One source of non-exhaust PM emission is studded tyre-pavement contact. A-state-of-the-art experimental machines must be developed and improved in order to make a contribution to decrease of non-exhaust PM emission consequently improving human health. This thesis carried out at the department of Machine Design at KTH Royal Institute of Technology deals with redesign of the tribometer available at the department premises to mount and test scaled down studded tyre-pavement PM generation. Three concepts of redesigned tribometer were generated and evaluated against each other, out of which one was selected to be designed in detail, manufactured, assembled and tested. Final concept validation was conduction of an experiment with studded and plain tyres running on a granite sample. PM10 and PM0.5 results were collected and analysed and final redesign of the tribometer was assessed. / I motsats till utsläpp av partiklar från vägtransporter har utsläpp av partiklar från andra källor än avgaser inte minskat avsevärt under de senaste åren. En källa till utsläpp av partiklar utöver avgaser är kontakten mellan dubbdäck och vägbana. Det är nödvändigt att utveckla och förbättra de senaste laborationsmaskinerna för att kunna bidra till att minska icke avgasrelaterade utsläpp och därmed människors hälsa. Denna avhandling, som utförts vid avdelningen för maskinkonstruktion vid KTH (Kungliga Tekniska Högskolan), handlar om att omkonstruera den tribometer som finns tillgänglig vid institutionen för att kunna montera och testa en nedskalad produktion av partiklar från däck och beläggning med dubbdäck. Tre koncept för en omkonstruerad tribometer skapades och utvärderades mot varandra, varav en valdes ut för att konstrueras i detalj, tillverkas, monteras och testas. Den slutliga valideringen av konceptet bestod av att genomföra ett experiment med dubbade och vanliga däck som kördes på ett granitprov. PM10- och PM0.5-resultaten samlades in och analyserades, varpå den slutliga omkonstruktionen av tribometern utvärderades.

Particulate emissions from road transportation are known to have an adverse impact on human health as well the environment. As the effects become more palpable, stricter legislation have been proposed by regulating bodies. This puts forward a challenge for the automotive industry to develop after treatment technologies to fulfil the progressively stricter legislation. At present, the most common after-treatment technologies used for particulates are the diesel and gasoline particulate filters. The typical size distribution of the particles is such that the smallest particles in terms of size are in numbers the largest, although they are not influencing the total particle mass significantly. The most recent legislation have included restrictions on the particle number as well as particle mass. In this thesis numerical tools for studying the transport and interaction of particles in an exhaust flow are evaluated. The specific application is particle agglomeration as a mean to reduce the number of particles and manipulate the size distribution. As particles agglomerate the particle number distribution is shifted and larger sized agglomerates of particles are created reducing the number of ultra-fine particles. The particle agglomeration is obtained by forcing sudden acceleration and deceleration of the host gas carrying the particles by variations in the cross sectional areas of the geometry it is passing through. Initially, a simplified one dimensional model is utilized to assess the governing parameters of particle grouping. Grouping here means that the particles form and are transported in groups, thus increasing the probability for agglomeration. The lessons learned from the 1D-model are also used to design the three dimensional geometry: an axisymmetric corrugated pipe. Two different geometries are studied, they both have the same main pipe diameter but different diameter on the corrugations. The purpose is to find the potential onset of flow instabilities and the influence of 3D-effects such as recirculation on the agglomeration. The CFD simulations are performed using DES methodology. First the simulations are run without particles in a non pulsatile flow scenario. Later particles are added to the setup in a one way coupled approach (no particle-particle interaction). The main results were: 1) An additional criterion for grouping to the ones given in previous work on the 1D model is proposed. It is found that grouping is more likely if the combination of the pulse frequency and geometric wavelength is large. Furthermore, smooth pulse forms (modelling the modulation in the flow due to the geometry) yielded more grouping than other more abrupt pulse shapes. However, idealised inlet pulses underestimate the extent of grouping compared to actual engine pulses. 2) For the geometry with larger maximum cross sectional area stronger flow separation was observed along with higher turbulent kinetic energy. 3) Particles were added in the flow field and a reduction in the particle count was observed in the initial simulations for particles going from the first corrugated segment to the last. Natural extensions of the present work would be to consider pulsatile flow scenarios, particle-particle interaction and a polydisperse setup for the particles / <p>QC 20181008</p>

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京都大学 / 新制・課程博士 / 博士(工学) / 甲第23493号 / 工博第4905号 / 新制||工||1766(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高野 裕久, 教授 米田 稔, 准教授 上田 佳代 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

La contaminación atmosférica originada por la producción animal intensiva afecta al medio ambiente global, a la salud de las personas y al bienestar de los animales de la propia granja. Se trata de una problemática de creciente interés en países en los que, como en el caso de España, se ha investigado poco hasta el momento. Esta tesis doctoral se centra en la medición experimental de concentraciones y emisiones de gases (amoniaco, metano, óxido nitroso y dióxido de carbono) y partículas (PM10) en granjas de pollos de cebo y de conejos, principalmente en clima mediterráneo, analizando los factores que afectan a dichas emisiones. Para ello, la tesis se compone de cinco trabajos de investigación diferenciados, aunque estrechamente relacionados entre sí. En primer lugar, se estudia en detalle la metodología empleada para medir las emisiones, basado en un balance en el que las variables son la concentración de gases y el flujo de ventilación; por otra parte, se desarrolla un procedimiento para el análisis de la incertidumbre cuyo objetivo es obtener indicadores de la calidad de los resultados. En segundo lugar, se aborda la medición del flujo de ventilación en granjas comerciales mediante el desarrollo de un circuito para la adquisición de información sobre el funcionamiento de los ventiladores. Posteriormente, y en aplicación de los dos anteriores estudios, se determinan las emisiones de gases en dos granjas comerciales de conejos y una de pollos en el litoral mediterráneo español, obteniendo resultados muy útiles para la mejora del inventario nacional de emisiones. Finalmente, se ha cuantificado la influencia de la actividad de los pollos de engorde en las emisiones de partículas y de gases, y se ha evaluado la aplicabilidad de un método para la determinación indirecta de la ventilación basado en el balance de dióxido de carbono. Los resultados obtenidos en estos experimentos y en los correspondientes análisis contribuyen al conocimiento general acerca de las emisiones / Calvet Sanz, S. (2008). Experimental studies on gas and dust emissions to the atmosphere in rabbit and broiler buildings [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8304

[pt] As emissões de combustíveis fósseis derivados do petróleo têm um impacto significativo no meio ambiente, nas mudanças climáticas, na poluição do ar e outros. Por isso, existe um grande interesse por fontes alternativas de energia, principalmente aquelas que podem reduzir as emissões de poluentes atmosféricos. Este trabalho teve por objetivo avaliar os perfis das concentrações de poluentes regulamentados (material particulado e CO2) e não regulamentados (benzeno, tolueno, etilbenzeno, xilenos, HPA, hidrocarbonetos alifáticos, aldeídos e metais) originados da queima de diferentes combustíveis em um motor estacionário do ciclo diesel e verificar os possíveis efeitos toxicológicos utilizando células epiteliais brônquica. Os combustíveis utilizados foram: mistura binária diesel com 5 por cento de biodiesel (B5), biodiesel de soja (B100), biodiesel de soja aditivado (B100 adt) e etanol aditivado. Para obter uma maior confiabilidade dos resultados realizou-se a verificação do método para a determinação de monoaromáticos e aldeídos por meio de cromatografia gasosa com detector de ionização de chama (CG-DIC) e cromatografia líquida de alta eficiência (CLAE), respectivamente. O MP foi determinado por gravimetria, Os HPA associados ao MP foram determinados por cromatografia gasosa acoplada a espectrometria de massa (CG-EM), hidrocarbonetos alifáticos (HA) por CG-DIC e metais foram analisados por espectrometria de massa com plasma indutivamente acoplado (ICP-MS). Os perfis das concentrações foram avaliados considerando: o tempo de queima de combustível (15, 30 e 60 min) e, o tempo de armazenamento (7, 14 e 21 dias) a 40 graus Celsius, para avaliar os processos oxidativos que podem ocorrer durante o armazenamento, especialmente no caso do biodiesel. A operação do motor quando ele ainda está frio, por exemplo, em 15 minutos, apresentou maior emissão de MP, benzeno e etilbenzeno para o biodiesel de soja (B100) em comparação com a mistura de diesel com 5 por cento de biodiesel (B5). O estudo dos perfis das concentrações dos compostos mono aromáticos, hidrocarbonetos alifáticos e hidrocarbonetos policíclicos aromáticos (HPA) mostraram resultados semelhantes aos descritos na literatura, em que o combustível B5 emiti mais poluentes do que o biodiesel. No entanto, comparando alguns poluentes individualmente, as emissões de benzeno e etilbenzeno foram maiores para B100 e B100 adt. O B5 apresentou o maior perfil de concentração para a soma HPA na fase gasosa do que na forma particulada em períodos de funcionamento do motor mais longos. O tempo de armazenamento reduziu as emissões de MP em 40 por cento para B100, 20 por cento para B100 adt e 3 por cento para B5. Em relação à concentração de compostos aromáticos, a redução foi de aproximadamente 60 por cento desses poluentes para B100 e B100 adt. A menor emissão de poluentes foi durante a queima do etanol aditivado. / [en] The emissions of fossil fuels derived from oil have a significant impact on the environment, climate change, air pollution, and others. Therefore, there is great interest in alternative energy sources, especially those that can reduce emissions of air pollutants. The aim of this study was the evaluation of concentration profiles of criteria pollutants, particulate matter (PM) and CO2 and unregulated pollutants (i.e., benzene, toluene, ethylbenzene, xylenes, polycyclic aromatic hydrocarbons (PAH), aliphatic hydrocarbons, aldehyde and metals) originated from burning of different fuels: The evaluated fuels were the binary mixture of fossil diesel with 5 percent biodiesel (B5), biodiesel soybean (B100), additivated biodiesel soybean (B100 adt) and additivated ethanol using a stationary diesel engine cycle, operating at the speed of 1800 rpm and 0 percent load. For a larger reliability of results, the method validation for determination the monoaromatic and aldehydes by gas chromatography flame ionization detection (GC-FID) and high-performance liquid chromatography (HPLC), respectively. PM mass was determinate by gravimetry, PAH associated to the PM were determined by gas chromatography coupled to mass spectrometry (GC-MS), aliphatic hydrocarbons were determined by GC-FID, and metals were determined by inductively coupled plasma mass spectrometry (ICP-MS). The concentration profiles were evaluated considering: 1) burning time (15, 30, and 60 minutes) and; 2) storage time (7, 14, and 21 days) at 40 Celsius Degrees to evaluate the oxidative processes that occur during storage, especially for biodiesel. When it is still cold (i.e., 15 minutes), the operation of the engine showed negative effect on particulate matter (PM), benzene, and ethylbenzene emissions for B100 compared to B5. In this study, the concentration profiles of the monoaromatic, aliphatic hydrocarbons, and PAH showed similar results to those reported in the literature, where B5 fuel emits more pollutants than pure biodiesel. However, comparing some pollutants individually, the benzene and ethylbenzene emissions were higher for B100 and B100 adt. For long engine operation periods, B5 showed the highest concentration profile for the PAH sum in the gaseous in comparison to PAH sum in the particulate phase. The storage time reduced the PM emissions in 40 percent (B100), 20 percent (B100 adt), and 3 percent (B5). Regarding the concentration of aromatics, the reduction was circa 60 percent for B100 and B100 adt. The lowest emission of pollutants was observed for additived ethanol burning.

[pt] O estudo avaliou a melhoria na qualidade do ar com a substituição do fogão a lenha tradicional por um modelo ecoeficiente. O monitoramento foi realizado em duas fases: em julho de 2022, durante o uso do fogão tradicional, e em julho de 2023, com o fogão ecoeficiente, ambos na comunidade quilombola do Calolé, Cachoeira, BA. Como comparação, residências com fogões a GLP em São Gonçalo também foram analisadas. Sensores em tempo real mediram poluentes como Material Particulado (MP(2.5) e MP(10)), Dióxido de Carbono (CO2) e Formaldeído (HCHO), além de temperatura e umidade, com coleta adicional de MP(2.5) usando bomba de exposição. O material particulado apresentou maior variação entre os combustíveis. A troca para o fogão ecoeficiente reduziu significativamente a carga de poluentes nas cozinhas: MP(2.5) caiu de 138 mais ou menos 216 microg m(-3) para 45 mais ou menos 154 microg m(-3) e MP(10) de 202 mais ou menos 287 microg m(-3) para 59 mais ou menos 191 microg m(-3). Também foram observadas reduções de CO2 (477 mais ou menos 62 ppm para 443 mais ou menos 34 ppm) e HCHO (0,004 mais ou menos 0,004 mg m(-3) para 0,006 mais ou menos 0,002 mg m (-3)). A análise química do material particulado indicou a presença de hidrocarbonetos policíclicos aromáticos (HPA). O consumo de lenha reduziu em até 52 por cento após a troca do fogão. As concentrações médias observadas para fogões a GLP foram ainda menores: 12 mais ou menos 29 microg m(-3) para MP(2.5), 18 mais ou menos 41 microg m(-3) para MP(10), 506 mais ou menos 125 ppm para CO₂ e 0,013 mais ou menos 0,010 mg m(-3) para HCHO. / [en] The study evaluated the improvement in air quality following the replacement of traditional firewood stoves with an eco-efficient model. Monitoring was conducted in two phases: in July 2022, during the use of traditional stoves, and in July 2023, with eco-efficient stoves, both in the Calolé quilombola community, Cachoeira, BA. As a comparison, households using LPG stoves in São Gonçalo were also analyzed. Real-time sensors measured pollutants such as Particulate matter (PM(2.5) and PM(10),), Carbon Dioxide (CO2), and Formaldehyde (HCHO), along with temperature and humidity, with additional PM(2.5) samples collected using an exposure pump. Particulate matter showed the greatest variation among the fuels. The shift to eco-efficient stoves significantly reduced pollutant loads in the monitored kitchens: PM(2.5) decreased from 138 more or less 216 microg m(-3) to 45 more or less 154 microg m(-3), and PM(10) from 202 more or less 287 microg m(-3) to 59 more or less 191 microg m(-3). Reductions in CO2 (from 477 more or less 62 ppm to 443 more or less 34 ppm) and HCHO (from 0.004 more or less 0.004 mg m(-3) to 0.006 more or less 0.002 mg m(-3)) were also observed. Chemical analysis of the collected particulate matter indicated the presence of polycyclic aromatic hydrocarbons (PAHs). Firewood consumption decreased by 52 percent following the stove replacement. The average concentrations for LPG stoves were even lower: 11.6 more or less 29 microg m(-3) for PM(2.5), 18 more or less 41 microg m(-3) for PM(10), 506 more or less 125 ppm for CO₂, and 0.013 more or less 0.01 mg m(-3) for HCHO.