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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.

In the last few decades a significant effort has been stablished in the automotive industry as well as in academic community towards increasing the renewable fuels applications in internal combustion engines, such as alcohol and gas derived sources. Meanwhile, turbo charging direct-injection spark-ignition engines have become fundamental features to achieve downsizing purposes, increasing power generation efficiency and attending high restrictive emissions regulations that have being taking place recently. For this study, experimental tests were carried out in a single cylinder research engine considering direct injection (DI) and port fuel injection (PFI) operations with anhydrous ethanol. The aim of this paper is to present a review and conduct further investigation about methodologies applied for imaging post processing considering chemiluminescence technique applied in an optical research engine.

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.

This paper deals with the study of different design configurations for intake valves and valve seats on a current production cylinder head and their effect on airflow behavior and optimization, under steady flow condition. The analysis was performed trough a Design for Six-Sigma methodology (DFSS). The cases were simulated through computational fluid dynamics (CFD) software and a prototype considering the best configuration was built and tested at flow bench. Correlation between simulation and experimental data was performed in order to validate the results for current, as well as, for future studies. The goal is to determine how geometric design variations on intake valve profiles and valve seats affect airflow on the particular cylinder head.

This paper deals with the application of a natural gas direct injection spark ignition single- cylinder engine model. The research scope includes the air flow characterization during compression stroke and also the charge stratification. Piston bowl effects are analyzed during the gas jet deflection towards the spark plug (wall-guided effect) in order to guarantee the charge stratification in this region, as well as an equivalence ratio which will result in the mixture combustion. The influence of two different swirl ratios in the parameters discussed above is analyzed. The goal is to obtain the evolution of the methane concentration in the cylinder during the gas jet development and the compression stroke. This result is an important reference to determine parameters such as the start of injection and the spark plug position so it could be applied in order to avoid the misfire occurrence.