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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.

Nowadays, the most common technologies used in the aircraft ice protection systems use indirect methods that identify atmospheric conditions prone to ice accretion, and not in fact the ice accretion over the surfaces, not measuring this accreted ice. On top of that, the ice protection systems are designed based on a certain flight phase considered the most critical for the system and its operation does not depend on the severity of the ice condition. Using direct methods for detecting the ice accretion on the protected areas and a control system based on the feedback of these sensors, it is possible to reduce the energetic consumption and measuring the ice accreted, optimize it, reducing the penalties for the propulsion system and the aircraft design.

The objective of this work is to perform a trade-off study between aircraft air conditioning systems based on conventional technology (Engine Pneumatic Bleed based) and the proposed bleedless architecture, based on the MEA (More Electric Aircraft) and Bleedless Engines concept. The pneumatic bleed system components are thus eliminated and a dedicated compressor serves as the main power supply to the air conditioning and pressurization system. Both the conventional and the proposed ECS architecture are described and the system main parameters are calculated. The aircraft used as baseline for the study is a typical regional jet. The operational characteristics and aspects of costs, weight, energy efficiency, maintainability and impacts on other systems of the aircraft were also considered. The proposed air conditioning architecture is compared to a conventional one in terms of weight, system price and power and fuel consumptions.