Le spectrofiltre est un filtre de Wiener utilisé pour isoler le bruit de combustion du moteur Diesel. Ce filtre est déterminé pour chaque point de fonctionnement et nécessite un traitement important des données. Il est donc difficile de mener des études perceptives sur le bruit de combustion obtenu selon plusieurs réglages moteur. Afin de pallier à cet inconvénient, cette thèse a pour objectif de définir un filtre commun qui puisse synthétiser un bruit de combustion en tout point de fonctionnement. Pour cela, une étude perceptive a montré que la substitution du spectrofiltre conventionnel par un autre filtre de Wiener permet la synthèse d’un bruit de combustion. L’utilisation d’un spectrofiltre commun est donc possible. L’analyse modale expérimentale permet d’estimer le filtre de Wiener à partir de données caractéristiques de la structure du moteur. Après analyse sur un signal synthétique, la méthode ESPRIT apparait la plus appropriée, mais nécessite quelques optimisations pour être adaptée aux particularités des spectrofiltres. Les filtres de Wiener de plusieurs régimes sont estimés selon différentes conditions d’estimation, définies par le critère ESTER. Une évolution fictive de l’amortissement selon le régime moteur est observée, et rattachée au fenêtrage temporel effectué dans le calcul du spectrofiltre. Une expérience perceptive est ensuite menée pour identifier si le critère ESTER permet d’estimer des filtres assez précis pour synthétiser des bruits de combustion similaires aux bruits de combustion conventionnels. Les résultats amènent à concevoir le spectrofiltre obtenu au ralenti comme un bon filtre commun, tant d’un point de vue physique que perceptif. / The spectrofilter is a Wiener filter used to extract combustion noise. This filter requires an important data processing and is determined in all operating conditions. Thus it is difficult to carry out perceptual studies on combustion noise from various motor adjustments. To overcome this drawback, this PhD dissertation aims to define a common filter which can synthesize a combustion noise in all operating conditions. For this, a perceptual study showed that the substitution of the conventional spectrofilter by another Wiener filter allows the synthesis of a combustion noise. The use of a common spectrofilter is thus possible. The experimental modal analysis allows to estimate the Wiener filter from characteristic data of the engine structure. After studying on a synthetic signal, the ESPRIT method seems to be the most appropriate, but requires some optimizations to be adapted to spectrofilter peculiarities. The Wiener filters of several running speeds are estimated in different estimating conditions, defined by the ESTER criterion. A fictitious damping evolution with the running speed is observed and linked to the temporal windowing applied on the spectrofilter computation. A perceptual experience is then carried out to identify if the ESTER criterion allows to estimate accurately filters to synthesize combustion noises similar to conventional combustion noises. The results lead to conceive the spectrofilter obtained in idling condition as a good common filter, as in a physical point of view that perception.

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.

[pt] Com a assinatura da Lei 11.097 de 13 de Janeiro de 2005, o Biodiesel fica introduzido na matriz energética brasileira. Até o fim de 2007, a mistura deste biocombustível ao diesel mineral, derivado do petróleo, é voluntária pelas distribuidoras de combustíveis. A partir de Janeiro de 2008, todo o óleo diesel será comercializado obrigatoriamente com 2% de Biodiesel misturado e, a partir de 2013 a mistura deverá conter 5% de Biodiesel. O mercado potencial de Biodiesel para esta meta de 2008 é de aproximadamente 800 mil toneladas anuais. Revela-se, portanto, um enorme esforço de todas as esferas interessadas neste mercado: instituições de ensino e pesquisa, agro-indústrias, indústrias ligadas ao setor energético, entre outras, com objetivo de se atingir a meta estipulada pela Lei. Como parte deste esforço, no presente trabalho foram levantados aspectos técnicos, econômicos, sociais e ambientais sobre a implementação do programa de implementação do Biodiesel na matriz energética brasileira, visando identificar os prós e contras da utilização deste biocombustível. Um modelo de análise termodinâmica de uma usina termelétrica foi desenvolvido para descrever o comportamento de motores ciclo diesel de grande porte operando com 4 tipos diferentes de Óleo Combustível e 5 tipos de Biodiesel. / [en] With the Federal Act number 11.097, from January 13, 2005, Biodiesel is introduced in the Brazilian energy matrix. To the end of 2007, a voluntary mixture of this fuel to mineral diesel oil can be prepared by fuel distributors. From January 2008, diesel oil will have to be commercialized with 2% of Biodiesel. This percentage is to be increased to 5% by 2013. The goal for 2008 means, approximately, 800 thousand ton of Biodiesel annually. All parts involved, universities, research institutes, agro business and energy industries, among others, have been putting a great deal of effort to meet the target set by Federal Government. The present work is a small contribution to this effort. Technical, economical, social and environmental aspects of the problem have been taking into account in the present study, in order to identify pros and cons of the utilization of Biodiesel. A simple thermodynamic model of a thermal-electric power plant was developed to predict the behavior of a large capacity diesel engine operating with conventional fuel (four different types of fuel oil) and with Biodiesel.

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.

Dans l’environnement concurrentiel d’aujourd’hui, la mondialisation des marchés et les enjeux socio-écologiques du développement durable représentent des défis majeurs pour l’industrie automobile. Afin de relever ces défis, les entreprises doivent investir dans des outils de développent plus performants. Pour améliorer la performance d’un moteur thermique en termes de consommation et d’émissions une compréhension enrichie de la boucle d’air autour du moteur et de l’interaction entre ses composants est indispensable Cette thèse suit deux axes de recherche dans ce contexte. Dans un premier temps, les problèmes liés à la modélisation d’une boucle d’air globale sont traités. En particulier, sont modélisés le débit d’air entre les différents sous-systèmes, la combustion en fonction du degré vilebrequin, la pulsation du débit et de la pression et l’estimation de la force aérodynamique sur les vannes des turbocompresseurs à géométrie variable (TGV). Cette étude de modélisation détaillée à été utilisée pour mettre en place un simulateur de la boucle d’air, qui prend en compte ces interactions et qui peut prédire l’influence des sous-systèmes sur la boucle globale. En suite, l’effort de notre recherche a été consacré à la modélisation des actionneurs mécatroniques de la boucle d’air et de leur comportement non linéaire dû au frottement, aux variations de la température, etc. Un modèle dynamique non linéaire à été développé et intégré dans le simulateur. Ce modèle peut être adapté aux plusieurs types d’actionneurs commerciaux. Le simulateur complet à été implémenté sous AMESim pour les modèles du moteur et de la boucle d’air, et sous Simulink pour le contrôle. Les modèles ont été paramétrées selon les spécifications d’un moteur commercial et le simulateur à été validé expérimentalement. Finalement, des lois de commande robustes ont été étudiées pour le contrôle en position (contrôle locale) des actionneurs. Un contrôleur adaptatif à été développé pour garantir la performance des actionneurs malgré des changements dans le frottement, ainsi que dans la charge externe. La performance de toutes les méthodes étudiées, a été validée expérimentalement. / Today’s globally competitive market and its associated environmental and social issues of sustainable development are major challenges for the automobile industry. To meet them, the industry needs to invest in high performance development tools. For improving engine performance in terms of consumption and emission, the interactions between the subsystems of the engine air-path need to be understood. This thesis followed two major axes of research in this context. First, the problems related to the modeling of the global air-path system were studied, which include the airflow characteristics between the different subsystems of the air-path, high frequency combustion modeling and pulsating airflow, and estimation of the exhaust aerodynamic force on the vanes of variable geometry turbochargers (VGT). The detailed modeling study was used for developing an engine air-path simulator, which takes into account these interactions and predicts the influence of subsystems on the global air-path. The second axis of research was focused on modeling of mechatronic actuators of the air-path, taking into account their nonlinear behavior due to friction and changes in operating conditions. A generic nonlinear dynamic model was developed and included in the simulator. This model can be adapted to most commercial actuators. The complete simulator has been implemented using AMESim for engine and air-path modeling, and Simulink for control. It has been parameterized according to the specifications of a commercial diesel engine and validated against experimental data. Finally, robust local controllers were studied for actuator position control, aimed at guaranteeing the performance of the actuators under parametric uncertainty and external disturbances. An advanced controller was developed, which adapts to changes in friction characteristics of the actuator and external load changes. The performance of all controllers has been demonstrated experimentally.

<p>This master thesis report discusses the use of self-organizing maps in a diesel engine management system. Self-organizing maps are one type of artificial neural networks that are good at visualizing data and solving classification problems. The system studied is the Vindax(R) development system from Axeon Ltd. By rewriting the problem formulation also function estimation and conditioning problems can be solved apart from classification problems. </p><p>In this report a feasibility study of the Vindax(R) development system is performed and for implementation the inlet air system is diagnosed and the engine torque is estimated. The results indicate that self-organizing maps can be used in future diagnosis functions as well as virtual sensors when physical models are hard to accomplish.</p>

This master thesis report discusses the use of self-organizing maps in a diesel engine management system. Self-organizing maps are one type of artificial neural networks that are good at visualizing data and solving classification problems. The system studied is the Vindax(R) development system from Axeon Ltd. By rewriting the problem formulation also function estimation and conditioning problems can be solved apart from classification problems. In this report a feasibility study of the Vindax(R) development system is performed and for implementation the inlet air system is diagnosed and the engine torque is estimated. The results indicate that self-organizing maps can be used in future diagnosis functions as well as virtual sensors when physical models are hard to accomplish.

In this study, canola oil has been selected for the test on a diesel engine and its suitability as an alternative fuel has been examined. To decrease the high viscosity of canola oil, the effect of temperature on viscosity has been researched. Then the fuel delivery system has been modified to heat canola oil before injecting the oil into the combustion chamber. Also, ethanol has been tested as an additive by blending with canola oil. An experimental setup has been installed according to standards to carry out tests. The set up has been controlled with a computer to take measurements more precisely and to perform experiment automatically. Experimental investigations have been conducted on a four cylinder, direct injection diesel engine. Full load-variable speed tests have been conducted to evaluate engine performance parameters. In addition 13 mode ESC test cycle has been performed to determine the exhaust emissions. Engine performance and emissions characteristics of canola oil and canola-ethanol blend containing 30% ethanol have been compared with those of baseline diesel fuel. Experimental results show that engine performance decreased for canola oil. Addition of ethanol into canola oil has been noticed to improve performance a little with respect to pure canola oil. Although, maximum performance has been obtained with diesel fuel, minimum specifics energy cost is obtained with canola oil. It has been observed that hydrocarbon (HC) emissions decrease with canola oil, blending ethanol with canola oil increase HC emissions and maximum values are read for diesel fuel. Carbon monoxide (CO) emissions have been observed to be the highest for canola oil but blending ethanol has a decreasing effect on CO emissions. As for particulate matter (PM), use of canola oil has been seen to be more pollutant than diesel but adding ethanol in canola reduces PM emissions significantly.

Disertacijos tyrimų aktualumą lemia energijos panaudojimo efektyvumo didinimas bei aplinkos taršos mažinimas transporto sektoriuje. Darbe sprendžiami eksperimentiniai, matematinio modeliavimo ir metodologiniai uždaviniai, siekiant kompleksiškai ištirti dyzelinių variklių, dirbančių II kartos RRME, alkoholio ir dyzelino mišiniais, eksploatacinius darbo rodiklius. Disertacijoje analizuotas ir įvertintas degalų mišinių panaudojimo lengvųjų automobilių ir pagalbiniame laivo dyzeliniuose varikliuose efektas. Tiriamojo darbo problematika, tikslas, uždaviniai suformuoti išanalizavus transporto sektoriaus sandarą, svarbą oro taršos ir energijos sunaudojimo srityse bei ES strateginius planus. Laboratorijos bei eksploatacijos sąlygomis ištirti I, II kartos biodegalų ir dyzelino mišiniai. Tyrimams panaudotuose varikliuose išbandyti butanolio ir metanolio su rapso metil/butilesteriais bei dyzelino 2 ir 3 komponentų mišiniai. Išbandyti II kartos RRME mišiniai: Sėjamosios judros (lot. Camelina sativa) kartu su kiaulienos RRME ir mikro dumblių (lot. Clorella sp.). Atlikti dyzelino ir mišinių palyginamieji variklinių savybių tyrimai. Panaudojant mišinius, energijos panaudojimo efektyvumas didėja ~1–4 %; esant šiek tiek išaugusiai NOX koncentracijai, CO, CH koncentracijos sumažėjimas siekia iki 20 %, o deginių dūmingumas – 55–85 %. Įvertinti terminės ir mechaninės apkrovos kriterijai, indikuojantys variklio konstrukcinį patikimumą dirbant dyzelinu ir degalų mišiniais. Ištirta biodyzelinų... [toliau žr. visą tekstą] / The relevance of dissertation research is determined increasing efficiency of energy use and reduction of environmental pollution in the transport sector. In order to accomplish the complex research of diesel engines (running on 2nd generation FAME, alcohol and diesel blends) performance indicators the experimental, simulation and methodological tasks are solved in dissertation. The analysis and evaluation of effect of fuel blends use in passenger car and vessel auxiliary diesel engines is presented in dissertation. The problem, aim, tasks of research work formulated after analysis of transport sector structure, the importance of air pollution and energy consumption and the EU's strategic plans. The blends of 1st and 2nd generation biofuels were investigated using laboratory equipment and in the exploitation conditions. 2 and 3 component blends of diesel, methanol, butanol, rape methyl/butyl esters were tested in diesel engines. Tested 2nd generation FAME blends: False flax (lat. Camelina sativa) with pork lards FAME and sea algae (lat. Clorella sp.). The comparable research of parameters while engine ran on diesel and blends was carried out. In the case of blends use the energy efficiency increases ~1–4%; at slightly increased NOX concentration the CO and CH concentrations decreased up to 20% and exhaust smoke, and smokiness decreased – 55–85%. The evaluation of thermal and mechanical load criteria which indicate 1.9 TDI 1Z engine reliability operating on diesel fuel and... [to full text]

One major aspect of environmental pollution affecting human life and climate is air pollution. The harmful pollutants in the air include mostly hydrocarbons, carbon monoxide, carbon dioxide, nitrogen oxides as well as soot and other particulate matter. These pollutants result in several damaging effects on environment and living beings which include acid rain, photochemical smog, global warming and various health hazards in human beings even cancer. Major contribution of these pollutants is from man-made sources such as industrial and automotive emissions that employ fossil fuels. In our country, diesel constitutes more than 40% of the fossil fuel consumption. Studies show that diesel engine emissions contribute to 80% of nitrogen oxides amongst other air pollutants. In the context of stringent emission regulations being implemented all over the world, exhaust emission control, in general and nitrogen oxide emission in particular, is gaining significant importance. A review of recent literature indicates the significance and popularity of electrical discharge based non thermal plasma for exhaust cleaning applications in general, and NOx cleaning in particular. While the existing pre-combustion and catalyst based post-combustion nitrogen oxides (NOx) abatement techniques have inherent disadvantages owing to short shelf life, saturated engine modifications, cost concerns etc., the electrical discharge based non- thermal plasma techniques offer certain advantages in terms of cost and life factors. Several non-thermal plasma techniques viz., pulsed plasma, surface plasma, dielectric barrier discharge plasma etc., have been studied under different laboratory conditions. Interestingly, due to the high oxidizing environment that prevails in the discharge plasma zone, complete reduction of NOx by the plasma alone is becoming a challenging task. This has led the researchers to utilize additional processing techniques in cascade with discharge plasma. This additional gas cleaning technique may involve the use of adsorbents, catalysts or some other secondary treatment for eliminating the nitrogen oxides produced due to oxidizing reactions in the plasma chamber. One such additive can be an adsorbent, which can be commercially obtained or prepared from industrial wastes. In this thesis the adsorption properties of two industrial wastes were explored for the first time in conjunction with discharge plasma. The synergistic effect of plasma combined with an adsorbent shows promising results in NOx removal thus offering an effective solution to two environmental issues namely air pollution and open waste dumping. While the plasma, generally, refers to direct plasma treatment of exhaust, it can also be used for generation of ozone in a separate reactor which can subsequently be injected into the exhaust stream resulting in indirect plasma treatment. The current work focuses on both direct and indirect dielectric barrier discharge plasma treatment for NOx reduction in diesel engine exhaust cascaded with either oyster shells, a mariculture waste or lignite ash from lignite coal fired plant. Instead of conventional petro-diesel, biodiesel produced from the seeds of pongamia pinnata is used as the fuel. This biofuel, on one hand, causes considerable reduction in volatile organic compounds, particulate matter, soot, oil mist etc., but on the other hand may have higher concentrations of nitrogen oxides, an aspect that has motivated us to take up the research work envisaged in this thesis. It was observed in the laboratory environment that for a given power, both direct and indirect plasma treatments have resulted in NOx removal to the tune of 85 to 95% when cascaded with the adsorbents studied.