Automotive engines are becoming increasingly technically complex and associated legal emissions standards more restrictive, making the task of identifying optimum actuator settings to use significantly more difficult. Given these challenges, this research aims to develop a process for engine calibration optimisation by exploiting advanced mathematical methods. Validation of this work is based upon a case study describing a steady-state Diesel engine calibration problem. The calibration optimisation problem seeks an optimal combination of actuator settings that minimises fuel consumption, while simultaneously meeting or exceeding the legal emissions constraints over a specified drive cycle. As another engineering target, the engine control maps are required as smooth as possible. The Multidisciplinary Design Optimisation (MDO) Frameworks have been studied to develop the optimisation process for the steady state Diesel engine calibration optimisation problem. Two MDO strategies are proposed for formulating and addressing this optimisation problem, which are All At Once (AAO), Collaborative Optimisation. An innovative MDO formulation has been developed based on the Collaborative Optimisation application for Diesel engine calibration. Form the MDO implementations, the fuel consumption have been significantly improved, while keep the emission at same level compare with the bench mark solution provided by sponsoring company. More importantly, this research has shown the ability of MDO methodologies that manage and organize the Diesel engine calibration optimisation problem more effectively.

Investigar, em motores veiculares pesados, alimentados com combustível diesel, a emissão de dioxinas e furanos clorados (PCDD/Fs) e hidrocarbonetos policíclicos aromáticos (PAHs), através da análise de material particulado e gases do sistema de exaustão. Investigar a mutagenicidade do material particulado e gases coletados. Material e Métodos: Os testes de emissão foram feitos em banco de provas dinamométrico de bancada de acordo com Ciclo 13 Pontos de testes, utilizando-se motores Diesel nacionais de aplicação veícular. Um mini-túnel de diluição foi usado para obtenção de amostras de material particulado. As análises de PCDD/Fs e PAHs foram realizadas em laboratório nacional. Para a análise de PCDD/Fs utilizou-se o método USEPA 8290 (1994) e para a análise de PAHs foi utilizado o método USEPA TO 13A (1999). A análise de mutagenicidade foi realizada de acordo com o Teste de Ames (TA98). Resultados: As medições de PCDD/Fs indicaram em geral valores abaixo do limite de detecção do método analítico. Em uma das amostras foi verificado que o OCDD ficou acima do limite de detecção, enquanto em outra isto ocorreu para o OCDF e para o 1,2,3,7,8-PeCDF. Em relação aos PAHs analisados verificou-se a presença dos seguintes compostos: Naftaleno, Acenaftileno, Acenafteno, Fluoreno, Fenantreno, Antraceno, Fluoranteno, Pireno, Benzo[a]antraceno, Criseno, Benzo[b]fluoranteno, Benzo[k]fluoranteno. A média encontrada para 5 amostras analisadas foi de 3.580,5 µg/g de material particulado. Os PAHs encontrados neste trabalho indicam alguma similaridade com a literatura disponível, para valores em % e µg/g de material particulado total coletado. O teste de Ames indicou que o material particulado coletado de motores diesel tem alta atividade mutagênica. Conclusões: A emissão de PCDD/Fs, para o nível de tecnologia dos motores Diesel testados mostrou-se pouco significativa, considerando-se combustível conforme especificado e método e limite de detecção utillizados. Em relação aos PAHs, os resultados indicaram que motores diesel têm uma contribuição importante na formação destes compostos. A alta atividade mutagênica observada mostra que as emissões de veículos Diesel são potencialmente tóxicas. Recomenda-se a continuidade de estudos para definição da regulamentação desses poluentes. / To investigate emission of chlorinated dioxins and furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs) in heavy duty diesel engines, through the analysis of particulate material and gases in the exhaust.To verify mutagenicity of collected particulate material and gasesous sample extracts. Material and Methods: The engine emissions tests were done in dynamometer test bench according to 13-Mode Cycle, using brazilian engines, vehicle application. A mini dilution tunnel was used to obtain particulate matter and gaseous sample. PCDD/Fs and PAHs analyses were carried out in a certified national laboratory. Dioxins and furans were analyzed according with Method 8290 (USEPA, 1994) and PAHs by Method TO13A (USEPA, 1999). The mutagenicity analyses were done in accordance with Ames test (TA98) Results: The measurements of dioxins and furans in diesel engines operating in controlled conditions in dynamomter bench test, had indicated emissions values in general below the detention limit of the analytical method. In one of the samples it was verified that the OCDD was above the detention limit, while in another one this occurred for OCDF and 1,2,3,7,8-PeCDF. In relation to 16 PAHs it was verified the presence of the following compounds: Naphthalene, Acenaphthylene, Acenaphthene, Fluorene, Phenanthrene, Antracene, Fluorantene, Pyrene, Benzo[a]antracene, Chrysene, Benzo[b]fluoranthene and Benzo[k]fluorantene. The average value of the sum of PAHs found in five samples was 3,580.5 µg.g-1. The PAHs found in this study indicates some similarity with available literature for values in % and µg/g of particulate matter.The Ames test showed that the collected particulate material from diesel engines presents high mutagenic activity. Conclusion: The emission of PCDD/Fs, for the level of technology of the tested Diesel engines revealed little significant, considering the specified fuel, method of analysis and limit of detention used. In relation to the 16 PAHs, the tests results had indicated that diesel engines has an important contribution in the formation of these compounds. The high mutagenic activity observed shows that the emissions of Diesel vehicles are potentially toxic. The continuity of studies for definition of the regulation of these pollutants is recommended.

The transportation sector continues to be a primary source of greenhouse gas (GHG) emissions, contributing more than any other sector in the United States in 2017. Medium-duty and heavy-duty trucks trail only passenger cars as the largest GHG contributor in this sector [1]. The intense operating requirements of these vehicles create a reliance on the diesel engine that is projected to last for many decades. Therefore, it is vital that the efficiency and environmental sustainability of diesel engines continue to be advanced.<br><br>Cylinder deactivation (CDA) is a promising technology to improve diesel engine fuel efficiency and aftertreatment thermal management for emissions reduction. This work presents original experimental results demonstrating fuel efficiency improvements of CDA implemented on a modern engine at idle operating conditions through testing of various CDA configurations. Idle calibration optimizations result in up to 28% fuel consumption reduction at steady-state unloaded idle operation and 0.7% fuel consumption reduction over HD-FTP drive cycles at equivalent emissions levels. The low-load thermal management performance of CDA is also investigated through creep and extended idle transient cycles, during which CDA is shown to reduce fuel consumption by up to 40% with similar thermal management performance and reduced NOx and soot emissions. <br><br>Variants of CDA implementation are explored through an experimental comparison of deactivation strategies. The effort described here compares charge trapping strategies through examination of in-cylinder pressures following deactivation because: (1) choice of trapping strategy dictates the in-cylinder pressure characteristics of the deactivated cylinders, and (2) deactivated cylinders can affect torque, oil consumption, and emissions upon reactivation. Results discussed here suggest no significant differences between the strategies. As an example, the in-cylinder pressures of both trapping strategies are shown to converge as quickly as 0.8 seconds after deactivation.<br><br>Finally, the NVH effects of CDA are characterized through studies of torsional vibration, linear vibration, and acoustics. CDA causes frequency content at reduced frequencies compared to conventional operation, which has effects on all aspects of NVH. This creates possible constraints on achievable fuel efficiency and thermal management performance by restricting CDA usage. An alternate form of CDA, dynamic cylinder activation (DCA), is explored as a possible option of avoiding undesirable frequency output while maintaining the desired engine performance. <br>

Environmental pollution is an important problem of our world. Governments are aware of this problem and emission regulations are continuously improved. One of the strictest regulations is about unburned and burned hydrocarbon emissions. In internal combustion engines the origin of the burned and unburned hydrocarbons is fuel and engine oil. As a result of the sanctions and the necessity of improved combustion performance of the engine, manufacturers work on manufacturing technology and engine tribology. With the improvement of these areas oil loss from internal combustion engine is reduced. Engine oil consumption mechanisms are specific research areas in the internal combustion engine development. Oil consumption occurs via to two main routes: &ldquo / Valve train&rdquo / and &ldquo / in cylinder components&rdquo / . In cylinder components have three sub mechanisms: evaporation, ring scraping and blowback. In this thesis, blowback oil loss mechanism is studied. 2D flow model of piston-cylinder mechanism is developed in Fluent. Land pressures and ring end gap flow data are taken from this model. An iterative computer program is developed to calculate backflow oil consumption. In this program, an empirical entrainment correlation compiled from literature is used. The calculated oil consumption values match with the range of the values in the literature.

Investigar, em motores veiculares pesados, alimentados com combustível diesel, a emissão de dioxinas e furanos clorados (PCDD/Fs) e hidrocarbonetos policíclicos aromáticos (PAHs), através da análise de material particulado e gases do sistema de exaustão. Investigar a mutagenicidade do material particulado e gases coletados. Material e Métodos: Os testes de emissão foram feitos em banco de provas dinamométrico de bancada de acordo com Ciclo 13 Pontos de testes, utilizando-se motores Diesel nacionais de aplicação veícular. Um mini-túnel de diluição foi usado para obtenção de amostras de material particulado. As análises de PCDD/Fs e PAHs foram realizadas em laboratório nacional. Para a análise de PCDD/Fs utilizou-se o método USEPA 8290 (1994) e para a análise de PAHs foi utilizado o método USEPA TO 13A (1999). A análise de mutagenicidade foi realizada de acordo com o Teste de Ames (TA98). Resultados: As medições de PCDD/Fs indicaram em geral valores abaixo do limite de detecção do método analítico. Em uma das amostras foi verificado que o OCDD ficou acima do limite de detecção, enquanto em outra isto ocorreu para o OCDF e para o 1,2,3,7,8-PeCDF. Em relação aos PAHs analisados verificou-se a presença dos seguintes compostos: Naftaleno, Acenaftileno, Acenafteno, Fluoreno, Fenantreno, Antraceno, Fluoranteno, Pireno, Benzo[a]antraceno, Criseno, Benzo[b]fluoranteno, Benzo[k]fluoranteno. A média encontrada para 5 amostras analisadas foi de 3.580,5 µg/g de material particulado. Os PAHs encontrados neste trabalho indicam alguma similaridade com a literatura disponível, para valores em % e µg/g de material particulado total coletado. O teste de Ames indicou que o material particulado coletado de motores diesel tem alta atividade mutagênica. Conclusões: A emissão de PCDD/Fs, para o nível de tecnologia dos motores Diesel testados mostrou-se pouco significativa, considerando-se combustível conforme especificado e método e limite de detecção utillizados. Em relação aos PAHs, os resultados indicaram que motores diesel têm uma contribuição importante na formação destes compostos. A alta atividade mutagênica observada mostra que as emissões de veículos Diesel são potencialmente tóxicas. Recomenda-se a continuidade de estudos para definição da regulamentação desses poluentes. / To investigate emission of chlorinated dioxins and furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs) in heavy duty diesel engines, through the analysis of particulate material and gases in the exhaust.To verify mutagenicity of collected particulate material and gasesous sample extracts. Material and Methods: The engine emissions tests were done in dynamometer test bench according to 13-Mode Cycle, using brazilian engines, vehicle application. A mini dilution tunnel was used to obtain particulate matter and gaseous sample. PCDD/Fs and PAHs analyses were carried out in a certified national laboratory. Dioxins and furans were analyzed according with Method 8290 (USEPA, 1994) and PAHs by Method TO13A (USEPA, 1999). The mutagenicity analyses were done in accordance with Ames test (TA98) Results: The measurements of dioxins and furans in diesel engines operating in controlled conditions in dynamomter bench test, had indicated emissions values in general below the detention limit of the analytical method. In one of the samples it was verified that the OCDD was above the detention limit, while in another one this occurred for OCDF and 1,2,3,7,8-PeCDF. In relation to 16 PAHs it was verified the presence of the following compounds: Naphthalene, Acenaphthylene, Acenaphthene, Fluorene, Phenanthrene, Antracene, Fluorantene, Pyrene, Benzo[a]antracene, Chrysene, Benzo[b]fluoranthene and Benzo[k]fluorantene. The average value of the sum of PAHs found in five samples was 3,580.5 µg.g-1. The PAHs found in this study indicates some similarity with available literature for values in % and µg/g of particulate matter.The Ames test showed that the collected particulate material from diesel engines presents high mutagenic activity. Conclusion: The emission of PCDD/Fs, for the level of technology of the tested Diesel engines revealed little significant, considering the specified fuel, method of analysis and limit of detention used. In relation to the 16 PAHs, the tests results had indicated that diesel engines has an important contribution in the formation of these compounds. The high mutagenic activity observed shows that the emissions of Diesel vehicles are potentially toxic. The continuity of studies for definition of the regulation of these pollutants is recommended.

No description available.

El proceso de atomización desde una vena o lámina líquida hasta multitud de gotas dispersas en un medio gaseoso ha sido un fenómeno de interés desde hace varias décadas, especialmente en el campo de los motores de combustión interna alternativos. Multitud de estudios experimentales han sido publicados al respecto, pues una buena mezcla de aire-combustible asegura una evaporación y combustión mucho más eficientes, aumentando la potencia del motor y reduciendo la cantidad de contaminantes emitidos. Con el auge de las técnicas computacionales, muchos modelos han sido desarrollados para estudiar este proceso de atomización y mezcla. Uno de los últimos modelos que han aparecido es el llamado ELSA (Eulerian-Lagrangian Spray Atomization), que utiliza un modelo Euleriano para la parte densa del chorro y cambia a un modelo Lagrangiano cuando la concentración de líquido es suficientemente pequeña, aprovechando de esta manera las ventajas de ambos. En el presente trabajo se ha desarrollado un modelo puramente Euleriano para estudiar la influencia de la geometría interna de la tobera de inyección en el proceso de atomización y mezcla. Se ha estudiado únicamente el proceso de inyección diésel. Este modelo permite resolver en un único dominio el flujo interno y el externo, evitando así las comunes simplificaciones y limitaciones de la interpolación entre ambos dominios resueltos por separado. Los resultados actuales son prometedores, el modelo predice con un error aceptable la penetración del chorro, el flujo másico y de cantidad de movimiento, los perfiles de velocidad y concentración, así como otros parámetros característicos del chorro. / Martí Gómez-Aldaraví, P. (2014). DEVELOPMENT OF A COMPUTATIONAL MODEL FOR A SIMULTANEOUS SIMULATION OF INTERNAL FLOW AND SPRAY BREAK-UP OF THE DIESEL INJECTION PROCESS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/43719 / TESIS / Premios Extraordinarios de tesis doctorales

Automotive engines are becoming increasingly technically complex and associated legal emissions standards more restrictive, making the task of identifying optimum actuator settings to use significantly more difficult. Given these challenges, this research aims to develop a process for engine calibration optimisation by exploiting advanced mathematical methods. Validation of this work is based upon a case study describing a steady-state Diesel engine calibration problem. The calibration optimisation problem seeks an optimal combination of actuator settings that minimises fuel consumption, while simultaneously meeting or exceeding the legal emissions constraints over a specified drive cycle. As another engineering target, the engine control maps are required as smooth as possible. The Multidisciplinary Design Optimisation (MDO) Frameworks have been studied to develop the optimisation process for the steady state Diesel engine calibration optimisation problem. Two MDO strategies are proposed for formulating and addressing this optimisation problem, which are All At Once (AAO), Collaborative Optimisation. An innovative MDO formulation has been developed based on the Collaborative Optimisation application for Diesel engine calibration. Form the MDO implementations, the fuel consumption have been significantly improved, while keep the emission at same level compare with the bench mark solution provided by sponsoring company. More importantly, this research has shown the ability of MDO methodologies that manage and organize the Diesel engine calibration optimisation problem more effectively. / Jaguar Land Rover

Motivado pela grande necessidade da utilização de combustíveis alternativos, o presente trabalho apresenta o estudo experimental e simulação termodinâmica (zero-dimensional) do desempenho de um motor de combustão interna de ignição por compressão utilizando álcool e óleo Diesel. Primeiramente são apresentados definições e conceitos relacionados a motores de combustão interna; a seguir apresenta-se o problema e os objetivos almejados. Posteriomente apresentam-se os resultados obtidos em dinamômetro confrontando-os com uma simulação no software Chemkin®. Dos resultados obtidos em dinamômetro, destacam-se as comparações das curvas características do motor para ambos os combustíveis. Também é discutida a metodologia empregada e as modificações realizadas. Todas as modificações realizadas no motor foram realizadas com o uso de componentes comercialmente disponíveis. Utilizou-se como facilitador da ignição, para o álcool, o \"Princípio do Ponto Quente\". As curvas características para ambos os combustíveis foram obtidas segundo a norma NBR-ISO 1585. Mediu-se, também, consumo de combustível, pressão na câmara de combustão e temperaturas do sistema. Destes dados obtém-se a comparação da pressão de combustão para os dois combustíveis. É feita também a comparação entre as pressões de combustão obtidas com a simulação termodinâmica. Esses resultados, por um lado, sustentam a viabilidade desta substituição entre os combustíveis, por outro lado mostram as dificuldades em se utilizar um combustível alternativo como o álcool nos motores de ignição por compressão. / Due to a huge necessity to use alternatives fuels, this study presents an experimental performance investigation and it\'s thermodynamics simulation (zero-dimensional) of an ignition engine Diesel cycle working with ethanol and Diesel. First of all some definitions and concepts related to internal combustion engines are given. Following this, an explanation of the problem and the aims are exposed; after that the dynamometer data have been presented and compared with engine simulation carried out with Chemkin®. From the dynamometer data, characteristics performance curves for both fuels can be highlighted. The applied methodology and technical modifications are also presented. All changes proposed in the engine are based on commercial components. To facilitate the mixture ignition into the combustion chamber, the glow plugs principle was used. Dynamometer tests were carried out according to norms NBR ISO 1585. Fuel consumption, chamber pressure and temperatures were also acquired. From these data combustion pressure for both fuels are compared. The experimental pressure is compared also to the results obtained with the thermodynamics simulation. The present results show the possibility of interchangeability between the ethanol and diesel in a compression ignition engines.

Motivado pela grande necessidade da utilização de combustíveis alternativos, o presente trabalho apresenta o estudo experimental e simulação termodinâmica (zero-dimensional) do desempenho de um motor de combustão interna de ignição por compressão utilizando álcool e óleo Diesel. Primeiramente são apresentados definições e conceitos relacionados a motores de combustão interna; a seguir apresenta-se o problema e os objetivos almejados. Posteriomente apresentam-se os resultados obtidos em dinamômetro confrontando-os com uma simulação no software Chemkin®. Dos resultados obtidos em dinamômetro, destacam-se as comparações das curvas características do motor para ambos os combustíveis. Também é discutida a metodologia empregada e as modificações realizadas. Todas as modificações realizadas no motor foram realizadas com o uso de componentes comercialmente disponíveis. Utilizou-se como facilitador da ignição, para o álcool, o \"Princípio do Ponto Quente\". As curvas características para ambos os combustíveis foram obtidas segundo a norma NBR-ISO 1585. Mediu-se, também, consumo de combustível, pressão na câmara de combustão e temperaturas do sistema. Destes dados obtém-se a comparação da pressão de combustão para os dois combustíveis. É feita também a comparação entre as pressões de combustão obtidas com a simulação termodinâmica. Esses resultados, por um lado, sustentam a viabilidade desta substituição entre os combustíveis, por outro lado mostram as dificuldades em se utilizar um combustível alternativo como o álcool nos motores de ignição por compressão. / Due to a huge necessity to use alternatives fuels, this study presents an experimental performance investigation and it\'s thermodynamics simulation (zero-dimensional) of an ignition engine Diesel cycle working with ethanol and Diesel. First of all some definitions and concepts related to internal combustion engines are given. Following this, an explanation of the problem and the aims are exposed; after that the dynamometer data have been presented and compared with engine simulation carried out with Chemkin®. From the dynamometer data, characteristics performance curves for both fuels can be highlighted. The applied methodology and technical modifications are also presented. All changes proposed in the engine are based on commercial components. To facilitate the mixture ignition into the combustion chamber, the glow plugs principle was used. Dynamometer tests were carried out according to norms NBR ISO 1585. Fuel consumption, chamber pressure and temperatures were also acquired. From these data combustion pressure for both fuels are compared. The experimental pressure is compared also to the results obtained with the thermodynamics simulation. The present results show the possibility of interchangeability between the ethanol and diesel in a compression ignition engines.