Este trabalho buscou estudar os efeitos do nível de Swirl e alteração da massa de combustível injetada nas emissões de poluentes de um motor Diesel. Foram selecionados 15 cabeçotes de uma população de 100 cabeçotes e agrupados pelo nível de Swirl. Como o motor testado utiliza 5 cabeçotes, 15 cabeçotes foram separados e classificados em 3 categorias pelo nível de Swirl. Em seguida, o motor foi montado com as 3 categorias de cabeçotes no dinamômetro com o objetivo de levantar os efeitos nas emissões de gases e parâmetros de desempenho do motor. Foram medidas as emissões de NOx, CO, THC, fuligem, fumaça e consumo de combustível nos 13 pontos do ciclo ESC, complementadas com medições de torque e potência à plena carga. Além disso, nas condições de plena carga foi explorado o efeito da alteração da massa de combustível injetado, pela mudança do ponto final de injeção, nos parâmetros de desempenho e emissões. / This work aimed at the investigation of the effects of the level of Swirl and the amount of fuel mass injected in the emissions of pollutants on a diesel engine. Cylinder heads were selected from a population of 100 cylinder heads and them grouped by Swirl level. As the engine used in the tests have 5 cylinder heads, 15 cylinder heads were separated into 3 categories by the Swirl level. The engine was mounted with the 3 Swirl level cylinder heads categories with the aim to investigate all effects on emissions and performance such as NOx, CO, THC, soot, smoke, fuel consumption, power and torque. The tests were performed following the ESC cycle and exploring the full load curve behavior with changes of the end of injection point, therefore altering the amount of fuel mass injected.

Made available in DSpace on 2017-07-10T15:14:39Z (GMT). No. of bitstreams: 1 Felipe_F_Klajn.pdf: 2683541 bytes, checksum: 0af15ef4ad0f8ff5cdbd67bc79b87c2b (MD5) Previous issue date: 2016-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The search for alternatives to reduce diesel within the national energy matrix, particularly within the transport sector, has been studied and carried out in a gradual manner with partial insertions of biodiesel to diesel. This binary mixture, however, can be improved by the addition of ethyl alcohol (ethanol), which contain oxygen atoms in its structure and may be able to promote more efficient burning and to reduce exhaust emissions, both sulfur and non-sulfur. This work aimed to evaluate the energy performance of an engine-generator set working with diesel-biodiesel blends and diesel-biodiesel-ethanol, compared with the diesel type "A", i.e, diesel without the addition of biodiesel, as well as physicochemical characteristics of each treatment. The diesel-biodiesel mixtures were based on the currently marketed formulation (B7) and projections provided by the Senate Bill 613/2015 and Resolution No. 3/2015 CNPE for captive consumers or road fleets, ie, B10, B15 and B20. Each binary mixture this has undergone additions of anhydrous ethanol (99.6% p / p) to 1%, 5%, 10% and 15%. The treatments were subjected to 5 resistive loads of 1, 2, 3, 4 and 5 kW in triplicate. The set of data collected, analyzed the density, viscosity, calorific value, specific consumption (CE), energy efficiency (EE) and SO2 emissions. The density and viscosity of the mixtures were close to the diesel and within the specifications of the National Agency of Petroleum, Natural Gas and Biofuels (ANP). The calorific value decreased as the biofuel incorporated into the diesel grew. The best specific fuel consumption was observed in absolute terms at a load of 5 kW for B15E1 with 327.1 g kW-1 h-1followed by B10E1 (330.1 g kW-1 h-1) and diesel (g kW-1 h-1). The ternary mixture composed by adding 1% ethanol did not differ statistically from diesel-biodiesel blends for all applied loads. The greatest EE of 27.15% was observed at the load of 4 kW, to B10E15 mixture. The B15E1 mixtures, B20E1 and B20E0 were more efficient than diesel for all applied loads. The lowest emission of SO2 was 5 kW for the load B10E0 with 397.66 ppm, while the highest was in load of 1 kW for B15E15 with 3391.67 ppm. / A busca de alternativas para a diminuição do uso de diesel dentro da matriz energética nacional, principalmente dentro do setor de transportes, tem sido estudada e realizada de modo gradativo com inserções parciais de biodiesel ao diesel. Esta mistura binária, entretanto, pode ser melhorada com a adição de álcool etílico (etanol), que por conter átomos de oxigênio em sua estrutura pode ser capaz de promover uma queima mais eficiente e reduzir as emissões gasosas, tanto sulfuradas quanto não sulfuradas. Assim, este trabalho buscou avaliar o desempenho energético de um conjunto motor-gerador trabalhando com misturas diesel-biodiesel e diesel-biodiesel-etanol, comparando com o diesel tipo A , isto é, diesel sem a adição de biodiesel, bem como características físico-químicas de cada tratamento. As misturas diesel-biodiesel tiveram como base a formulação atualmente comercializada (B7) e projeções previstas pelo Projeto de Lei do Senado 613/2015 e Resolução CNPE nº 3/2015 para frotas cativas ou consumidores rodoviários, isto é, B10, B15 e B20. Cada mistura binária desta sofreu adições de etanol anidro (99,6% p/p) a 1%, 5%, 10% e 15%. Os tratamentos foram submetidos a 5 cargas resistivas de 1, 2, 3, 4 e 5 kW, em triplicata. Do conjunto de dados colhidos, foram analisados a densidade, viscosidade, poder calorífico superior e inferior, consumo específico (CE), eficiência energética (EE) e as emissões de SO2. A densidade e viscosidade das misturas ficaram próximas ao diesel e dentro das especificações da Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP). O poder calorífico inferior diminuiu a medida que o teor de biocombustíveis incorporados ao diesel cresceu. O melhor consumo específico em termos absolutos foi verificado na carga de 5 kW, para B15E1, com 327,1 g kW-1 h-1 seguido de B10E1 (330,1 g kW-1 h-1) e do diesel (334,7 g kW-1 h-1). As misturas ternárias compostas pela adição de 1% de etanol não diferiram estatisticamente das misturas diesel-biodiesel para todas as cargas aplicadas. A maior EE verificada foi de 27,15%, na carga de 4 kW, para a mistura B10E15. As misturas B15E1, B20E1 e B20E0 foram mais eficientes que o diesel para todas as cargas aplicadas. A menor emissão de SO2 foi verificada na carga de 5 kW para a mistura B10E0, com 397,66 ppm, enquanto a maior foi na carga de 1 kW, para B15E15, com 3391,67 ppm.

Tese de mestrado integrado. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 2008

Tese de mestrado. Manutenção Industrial. Faculdade de Engenharia. Universidade do Porto. 2004

Estágio realizado na empresa Technická univerzita V Liberec e orientado pelo prof. Doutor Michael Vojtisek-Lom / Tese de mestrado integrado. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 2010

In this work, an investigation on the fraction of tyre pyrolysis oil with a similar distillation range to that of automotive diesel (150 – 360 oC) was carried out to determine its suitability as an alternative or additive to petro-diesel fuel. The quality of this oil was evaluated by comparing its key properties to the requirements of South African National Standards for Automotive diesel fuel (SANS-342) and to conventional automotive diesel fuel. The viscosity, density, copper strip corrosion of this fuel were found to be within the acceptable limits set by SANS while sulphur content and flash point were out of their respective set limits. In addition, mixing rule equations for predicting viscosity and density for both pure and blends of the oil as a function of temperature were developed and evaluated. The equations were found to be suitable due to their low Absolute Percentage Deviation. Engine performance tests were carried out with blends of Distilled Tyre Pyrolysis Oil (DTPO) and petro-diesel fuel in a single cylinder air cooled diesel engine. The performance, emission and combustion characteristics of the diesel engine while running on these blends were evaluated and subsequently, a comparative analysis was performed with conventional petro-diesel fuel as the reference fuel. It was found that, the engine could run with up to 60% (DTPO) without any problem. Beyond this level the engine became unstable. The power and torque were similar at low and medium speeds. However, at high speeds, the power dropped with increase in DTPO in the blend. Fuel consumption was very comparable for all the test fuels. Carbon monoxide and unburned hydrocarbons were higher for the blends compared to petro-diesel fuel but oxides of Nitrogen were lower. The peak pressure for petro-diesel fuel was marginally higher than that of the blends. Present results indicate that, petro-diesel fuel can be blended with up to 60% DTPO and produce acceptable performance. Testing the diesel engine under different operating conditions is a time consuming and expensive process that also requires the use of specialised equipment which may not be readily available. An Artificial Neural Network (ANN) model based on a back-propagation learning algorithm was developed to predict engine performance and emissions separately, based on fuel blend and speed. The performance and accuracy of the model were evaluated by comparing experimental and ANN predicted results. The ANN was able to predict both engine performance and emissions with acceptable levels of accuracy. The values of correlation coefficient between experimental and predicted data being greater than 0.99. From this work, it can be implied that engine emission and performance can be predicted using neural network-based mode, consequently, it will be able to do further investigations without running laboratory experiments. Energy recovery from waste is an interesting field for engineers and scientists. It is hoped that this work will prompt new research ideals on how tyre pyrolysis oil can be improved for use as diesel engine fuel and building better models for diesel engine performance and emissions

The introduction of alternative fuels such as natural gas is likely to occur at an increasing rate. The dual-fuel concept allows these low cetane number fuels to be used in compression-ignition (CI, diesel) type engines. Most CI engine conversions have pre-mixed the alternative fuel with air in the intake manifold while retaining diesel injection into the cylinder for ignition. The advantage is that it is simple for practical adaptation; the disadvantage is that good substitution levels are only obtained at midload. A better solution is to inject both the alternative and diesel fuels directly into the cylinder. Here, the fuel in the end-zone is limited and the diesel, injected before the alternative, has only a conventional ignition delay. This improves the high-end performance. Modern, very high pressure diesel injectors have good turndown characteristics as well as better controllability. This improves low-end performance and hence offers an ideal platform for a dual-fuel system. Several systems already exist, mainly for large marine engines but also a few for smaller, truck-sized engines. For the latter, the key is to produce a combined injector to handle both fuels which has the smallest diameter possible so that installation is readily achieved. There exists the potential for much improvement. A combined gas/diesel injection system based on small, high pressure common-rail injectors has been tested for fluid characteristics. Spray properties have been examined experimentally in a test rig and modelled using CFD. The CFD package Fluent was used to model the direct-injection of natural gas and diesel oil simultaneously into an engine. These models were initially calibrated using high-speed photographic visualisation of the jets. Both shadowgraph and schlieren techniques were employed to identify the gas jet itself as well as mixing regions within the flow. Different orientations and staging of the jets with respect to each other were simulated. Salient features of the two fuel jets were studied to optimise the design of a dual-fuel injector for CI engines. Analysis of the fuel-air mixture strength during the injection allowed the ignition delay to be estimated and thus the best staging of the jets to be determined.

Thesis (M. P. A.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

<p>To fulfil emission requirements specified by environment demands, such as Euro 4 and Euro 5, there is a need to utilize engines based on technologies such as Variable Turbine Geometry (VGT) and Exhaust Gas Recirculation (EGR). A model of an engine using VGT and EGR was created by Ph.D student Johan Wahlström at Linköping University. This thesis evaluates Wahlström's model and shows how it successfully describes the engine and its behaviour. The thesis also confirms theories about the occurrens of non.minimum phase behaviour in different transfer functions, e.g. from VGT signal to the mass flow through the compressor.</p><p>An interesting phenomenon when applying VGT and EGR is a nonlinearity leading to, for example, that the same pressure in the intake manifold can occur for two different VGT signals. Such phenomenon can cause problems when designing a control system. Furthermore, this nonlinearity also results in a replacement of the nonminimum phase behaviour with an overshoot when a large (above 80%) VGT control signal is used.</p><p>This thesis also provides a linearized model, which describes the engine satisfactory. The linearization results in transfer functions with two zeros and three poles, whose locations do not change much when varying engine speed and load (except at high load and low engine speed). This fact will most likely make it possible to utilize just a few different linearizations for all speeds and loads. However, altering VGT and EGR positions greatly affect the transfer functions. Thus, several linearizations are probably needed to cover all operating points.</p><p>When designing a future control system a good strategy is to utilize a decoupled system since the model has strong cross-connections. Another solution would be to apply multi dimensional control strategy, e.g. LQ-theory.</p>

<p>This essay is written within my education for Technical Officer in the Swedish armed forces. The essay describes the alternative fuels that the Swedish armed forces can make use of if the supply of fossil fuels is insecure. The alternative fuels that are described and compared are; Synthetic diesel, Organic diesel, Methanol and Ethanol. The essay describes the process of producing the alternatives, the need for modification and the economics for each alternative. The alternatives are compared and assessed for their ability to secure the supply of fuel to the Swedish Armed Forces. The result of the study is that, while synthetic diesel has the best chemical constitution but is not produced in Sweden, the best alternative fuel for the Swedish armed forces at this moment is organic diesel.</p>