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Hybrid vehicles have been developed for improving efficiency and the consequent reduction of fossil fuels consumption in the transportation sector. The complexity of such vehicles allows for countless architectures, being one of them the range extender concept, which corresponds to an electrically powered vehicle equipped with a small combustion engine to improve the vehicle range. In the literature there is no current consensus whether range extenders should adopt simple engine technology aiming at cost reduction, or should they incorporate complex systems in order to achieve a remarkable thermal efficiency and low emissions. In the context of exploring the advanced options for range extenders, the combustion characterization is a fundamental step, which provides information on combustion behavior for several fuel types under a wide range of combustion modes. That information can both yield useful insights for engine development and provide combustion datasets for engine simulation.

Compression ignition engines are widely used in the cargo and passenger transport sectors, this is due to their high energy efficiency and can operate with renewable fuels. The search for increased efficiency in internal combustion engines and reduced emissions are increasingly stringent, so to meet regulatory emission standards, new technologies are being studied and developed to reduce emissions generated by engines, in the case of diesel engines compression ignition, studies of techniques to reduce NOx and soot have been carried out. One of the techniques studied is the application of the DFI - Ducted Fuel Injection concept, which makes the fuel spray pass through a small cylindrical duct installed upstream of the injection orifice of the injector nozzle, thus improving the air/fuel, making it more homogeneous and allowing a more complete combustion. This work addresses a study of this application of DFI with different compression ratios.

Recently, the advance of computational fluid dynamics simulation applied on design of internal combustion engines (ICE) has highlighted the need of reliable chemical kinetics models for most common fuels applied on ICE operation, such as ethanol, gasoline and blends. Therefore, the mainly motivation for this study is determine and evaluate the influence of the water content on ethanol flames for laminar flame speed and chemical kinetics. For this goal, laminar flame speed measurements by OH-Emission and OH-PLIF were conducted on anhydrous and hydrous ethanol premixed flames at atmospheric pressure. Distinct fuel samples were evaluated at several equivalence ratios. Chemical kinetic simulation considering Marinov´s mechanism was performed in order to match velocities obtained from experimental data versus values obtained through numerical simulation, and to verify the characteristics of hydroxyl production at conditions studied.

Since 70′, ethanol has risen as an alternative and ecological fuel, it has also been pointed as a potential candidate for replacing partial, or even totally, oil derived fuel application on internal combustion engines, supporting automotive industry. Ethanol is obtained from renewable sources and contributes to pollutants emission reduction in the atmosphere. In Brazil, it is obtained from sugarcane, but it can be obtained from others vegetable growing, such as beet or corn, common in other countries. For Brazilian automotive applications two types of ethanol are commonly applied: anhydrous, that contains at most 0.4% water in volume and has been used in gasoline blends up to 27%; and hydrous, with a maximum water content of 4.9% in volume, used as a substitute to gasoline on flex fuels engines. Although the widely application of ethanol, there is still lack of data available in literature regarding the fuel properties.

The use of numerical simulations in the development processes of engineering products has been more frequent, since it enables prediction of premature failures and study of new promising concepts. In industry, numerical simulation has the function of reducing the necessary number of validation tests prior to spending resources on alternatives with lower likelihood of success. The internal combustion Diesel engine plays an important role in Brazil, since they are used extensively in automotive applications and commercial cargo transportation, mainly due to their relevant advantage in fuel consumption and reliability. In this case, the most critical pollutants are oxides of nitrogen (NOx) and particulate matter (PM) or soot. The reduction of their levels without affecting the engine performance is not a simple task. This paper presents a methodology for guiding the combustion analysis by the prediction of NOx emissions and soot using numerical simulation.

The technical evolution of turbofan engines has been accomplished by increasing the engine thermal and propulsive efficiencies. The former is mainly a function of component efficiencies, cycle temperatures and pressures, while the latter is basically related to the engine BPR and FPR. However, several technological challenges are faced to increase those levels of efficiencies. In the thermal efficiency side, higher pressure ratios, for a given stage loading, are obtained by increasing the number of compressor stages, adding weight and size penalties to the engine, and increasing the compressor delivery temperature. Higher cycle temperatures, mainly those found in the burner exit and the stator outlet require higher cooling flows, for a given blade material technology level. Higher cooling flows lead to penalties in the engine efficiency, since the air used in the cooling is bled from the compressor.