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Regulations have been established for the monitoring and reporting of greenhouse gas (GHG) emissions and fuel consumption from the transport sector. Low carbon fuels combined with new powertrain technologies have the potential to provide significant reductions in GHG emissions while decreasing the dependence on fossil fuel. In this study, a lean-burn ethanol-diesel dual-fuel combustion strategy has been used as means to improve upon the efficiency and emissions of a conventional diesel engine. Experiments have been performed on a 2.0 dm3 single cylinder heavy-duty engine equipped with port fuel injection of ethanol and a high-pressure common rail diesel injection system. Exhaust emissions and fuel consumption have been measured at a constant engine speed of 1200 rpm and various steady-state loads between 0.3 and 2.4 MPa net indicated mean effective pressure (IMEP).

The introduction of the flexible fuel vehicles in Brazil had the first objective to protect the customer against fuels - commercial gasoline (E22) and hydrated ethanol (E100 or AEHC) - price variations. Nevertheless, while the Flex technology became dominant in the Brazilian market, the environmental aspect of the possibility of using a renewable fuel, ethanol from sugar cane, increased in importance due to the reduction in non-recyclable CO₂ and its benefits for the greenhouse effect. The objective of this article is to propose a practical method to quantify the avoided CO₂ using available engine management system parameters, basic chemical calculations, literature information and simplifying assumptions. The resulting equations show that it is possible to have a practical avoided-CO₂ calculation procedure which can be performed on-board and used for customer information and for quantifying the environmental advantage of using ethanol in fleets of flexible fuel cars.

The search for better energetic efficiency of the flexible fuel engines will guide the next design changes in this technology. The use of direct injection and the downsizing of volumetric displacement compensated by supercharging is a possible solution to reduce the fuel consumption. The direct injection brings the thermodynamic benefits of the charge cooling; the reduced displacement reduces the pumping work in partial loads and engine friction, while the supercharging allows the performance of a bigger engine. The combination of these technologies with hydrated ethanol (E100 or AEHC) represents a performance and CO₂ reduction opportunity, but also a challenge in terms of cold start and durability. The objective of this study is to evaluate and compare the behavior and the potential in full load conditions of an engine equipped with direct fuel injection and turbocharger, using Brazilian Hydrated Bioethanol (called as E100) and Brazilian gasoline (called E22).

Due to the increasing importance of vehicle energy efficiency, design changes on flex fuel engines aiming fuel consumption and CO₂ emissions reduction becomes priority. It is known that, due to chemical difference between hydrated ethanol (E100) and commercial gasoline (E22), parameters as combustion pressure, burn speed and knock tendency vary according to the fuel and are decisive for the engine thermal efficiency. This study has the objective to show and quantify the influence of the cooling liquid temperature in these parameters and on the thermal, mechanical and global efficiencies of an Otto flexible fuel engine, aiming to observe opportunities of fuel consumption reduction and performance improvement, as a way to compensate the fixed compression rate of flex engines. The results show that it is possible to have better efficiency in partial and full loads, adjusting the cooling liquid temperature according to the used fuel.

Fuel consumption and CO₂ emission are important drivers of automotive industry product evolution. In Europe, the manufactures have the compromise to reduce their fleet consumption steadily and, in Brazil, a still voluntary but growing labeling program makes the vehicular energetic efficiency one of the main concerns during the concept phase. Different from the full hybrid technology, where the car can be driven purely by the electric motor, the mild hybrid has been mentioned in literature as cost-effective route to reduce CO₂ emissions through the combination of a highly responsive low power electric motor, which acts supporting the internal combustion engine in special driving situations, with energy recovery and storage system composed of advanced batteries. Therefore the mild hybrid system can be understood as one type of downsizing strategy.

Fuel consumption and CO₂ emission are important drivers of automotive industry product evolution. In Europe, the manufacturers have the compromise to reduce their fleet consumption steadily and, in Brazil, a still voluntary but growing labeling program makes the vehicular energetic efficiency one of the main concerns during the concept phase. Although powertrain efficiency plays a decisive role, also vehicular parameters such as weight, aerodynamic, tires rolling resistance and electrical and mechanical loads have an important influence on fuel consumption and CO₂ emissions. The cost-benefit analysis of the modifications in these parameters needs to be performed in the early project stages, where prototypes are still not available.

This paper presents a review on the fatigue mechanisms in automotive valve springs manufactured on high-strength steel, as well as in other similar parts, like as helical suspension spring. The review was conducted with a phenomenological focus to support new developments in material for use in Otto and Diesel engines. Mechanical fatigue is a common process of damage that occurs in components subjected to cyclic loads, but in the particular case of valve springs, this problem is controlled through the project restriction, usually with the limitation of higher levels prescription of shear stress. In an attempt to increase this limit, allowing greater efforts at the elastic region the Material Engineering designs materials with higher toughness and the Manufacturing Engineering plays in the prevention or defects minimization, often inherent to the material.

The development of innovative designs for mobility is a result of numerous studies that aim to discover new potential for projects or enhance existing ones. The automotive sector shares these aspirations. Looking briefly at how cars have evolved in their history and the speed with which they are improved, it is possible to see how these studies are essential and together with the design result in more efficient and better quality products. As important as an innovative Shape Design are the external and internal finishing of the car, they bear by themselves a thorough research of user trends and lifestyle, being therefore the starting point for the technical approach and viability of new technologies, colors and finishing that preserve and value of the product as a whole.

The globalization of the economy has increased competition and intense dispute for new markets. It has accelerated the evolution of technology in all segments. Manufacturing automation, robotics production lines, programmable logic controllers (PLC), simulation and offline programming of equipment technologies are known by the main companies, but the integration of these technologies is always a complex issue and requires timing. Actually it expands time in development of standards, in design software and simulations, while much work still remains to be done in the field. Aligned with the technology of Digital Factory there is a technology of Virtual Commissioning. With this technology it is possible to bring to the lab environment a lot of solutions found so far only in the installation phase. The real commissioning is still necessary, but with less activity and uncertainties.

The present article shows the effect of the mass and friction reduction inside the engine over the carbonic gas emission reduction in the atmosphere. Authors have confirmed that the mass reduction and low friction in the internal components of the OTTO cycle engine, achieved by exhaust and admission valves re-dimensioning and sealer's substitution can help to reduce fuel consumption and, consequently, CO2, the main greenhouse effect gas. It is exposed and discussed different measurements of torque and power curves, friction power, and specific fuel consumption compared in the same engine without the proposed improving actions.

This paper presents the development of a system that allows the decentralisation of the management of day-by-day activities. This is done by redistributing the responsibilities, in a clear and objective way, and forming teams capable of auto-management their manufacture process. This system is based in elementary management units (teams). This structure makes possible the fast and precise identification of non-conformity, providing a reply (specific actions of containment and correction) in a skilful time; preventing (of this form) that the problems become “epidemic” and that the non-conformity costs become greater and out of control. However, a review of support areas structures becomes necessary. Those areas, primordial functions are to support the teams in the resolution of the day-by-day problems and assuming the responsibility on the chronic problems (those on which the manufacture teams do not have resources to solve).