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Nowadays computer simulation is an important tool to support new internal combustion engine projects, but still further studies are necessary for its use in fuel development. In order to study the influence of fuel properties on engine combustion and emission performance, a computer model was designed based on a Flex-Fuel engine geometric data. Model was validated with experimental tests done on an engine dynamometer. A simulation software was used to simulate the experimental conditions, by using Wiebe two zone combustion and Woschni heat transfer models. In-cylinder maximum pressure, IMEP and emission data were calculated for different gasoline-hydrous ethanol blends at 3875 rpm, 60 Nm and 105 Nm. Total hydrocarbons concentration was simulated comparing the experimental data of hydrocarbons added with unburned ethanol emission measured with a FTIR analyzer.

This work presents a new methodology to evaluate intake valve and combustion chamber deposits formation on port injection flexible fuel spark-ignition engines. This test methodology was adapted from ASTM 6201 standard, using a commercial Brazilian engine that can be run with blends of gasoline and ethanol in any proportion from pure gasoline to pure ethanol. It also describes every step of the methodology development, test conditions and the main criteria discussed by workgroup created by The National Agency of Oil, Natural Gas and Biofuels - ANP to propose a suitable standard for Brazilian spark ignition engine's fuels. This methodology will also be used to evaluate the results of detergent dispersant additives that may comply with the compulsory Brazilian gasoline additivation that will be due at January 2014.

Experiments in engine test cells are under the influence of several parameters and types of equipment, which may impact the test results. Many variables of interest are derived from the combination of more than one quantity, increasing the results uncertainty of the final reported value. This paper describes a detailed procedure to calculate uncertainty of measurement of emission tests using a FTIR (Fourrier Transformed Infrared) emission analyzer. A Flex-Fuel engine using gasoline and ethanol was tested under different operating conditions on an engine dynamometer equipped with automation system. For each operating condition at least four different measurements were taken. The expanded uncertainty was calculated by the combination of Type A (due to repeatability) and Type B (due to calibration, sensor resolution and others).

This work has as its purpose to evaluate the greenhouse effect gases (GHGs) emissions from ethanol-powered buses, which were introduced in the urban transportation system of the city of São Paulo, in 2007, by means of Project BEST - BioEthanol for Sustainable Transport with the goal of promoting ethanol usage in substitution to diesel in public transportation, aiming at the reduction of atmospheric pollution in great urban centers and at the reduction of global warming. The engine is advanced even for the strict European emission standards, because it meets the EURO 5 specifications and the Enhanced Environmental Vehicle (EEV), besides surpassing the limits imposed by the P-7 stage of PROCONVE. Today, ethanol-powered buses became a reality, because the chassis and the engine, then imported, as well as the additive for the ethanol, are already manufactured in Brazil.

In internal combustion engine valves, wear often develops at the interface of the valve seat and the insert as a result of the high pressures produced by the combustion process at the moment of the closing event. An alternative to study the wear is by carrying out experimental tests in specific wear testing machines. The main drawback is that they are time consuming and expensive due to the need to carry out many tests for the usually observed scatter in the results. In the area of numerical methods, the wear simulation has been widely developed in the last years because it can solve complicated time consuming problems with general geometries. The aim of this work is to characterize the wear rate coefficients for bi-metallic pairs commonly used in internal combustion engine valves using experimental results and numerical solutions by using the Finite Element Method. Then, a numerical valve model is provided to demonstrate that the numerical and experimental solutions are in agreement.

Valve engine manufactures have to satisfy the demands of a market that requires to increase the strength of their products and to extend the time between servicing. In a combustion engine valve, the mechanical stresses are generated during the closing event by loads coming mainly from the return spring, the inertia loads of retainer, keeper and stem, closing velocity, valve tilt and the thermal loads from the combustion. The objective of this work is to understand the valve closing process, and to predict numerically the maximum stresses in new valve designs in a shorter time and at lower costs compared with experimental procedures. In this work, the experimental valve stem stress response under impact velocity was registered using strain gauges and then compared by Finite Element Method solutions showing good agreement.

Through a market analysis, PETROBRAS identified an opportunity to launch a new product dedicated to diesel boats market. This paper describes the activities performed by PETROBRAS research center (CENPES) during the new diesel development: new or improved methodologies to ensure reliable comparative performance, fuel consumption and smoke emissions analysis, with appropriate precision to elucidate differences between the new fuel and the conventional marine diesel. Performance tests were conducted by using radar monitoring. For fuel consumption, constant engine speed tests were made, with fuel flow measurement and acquisition. Smoke tests were performed using a total flow smokemeter, installed directly on the exhaust gas pipe. Results showed that, because of its special characteristics, the new diesel allows performance gains up to 6% and smoke emissions reduction up to 83%. Fuel consumption remains in the same level of regular marine diesel.

This paper describes a computational and experimental study to document the detailed flow field around a prototyping vehicle, used as tool in the preliminary design process. The concept car called ALLSCAPE has obtained the 3th place at IV International concourse of design Peugeot P.L.E.A.S.E. Innovate 2007. Experimental tools of fluid mechanic will be used to know the aerodynamic behavior of this future prototype. The methodology propose was based on studies of the body in a subsonic wind tunnel with a cross-sectional section of 0,45×0,45 m and rank of speeds from 5m/s to 35m/s. A similarity study was made geometric and dynamic which result in a 1:12 scale model. Also an artificial ground was used to in order to create the ground effect in this varied the separation between the model and the ground. The computational methodology used was CFD (Computational Fluid Dynamics). The software used was the ANSYS-CFX 10.0TM.

This paper assesses the use of E85 fuel in Brazilian flex fuel light duty vehicles. E85 is composed of 85% of anhydrous ethanol and 15% of gasoline in volume base. Advantages and disadvantages of the E85 use are presented in comparison to hydrated ethanol (H100) that is currently available in the Brazilian market. Additionally, the blend H81 made by 81% of hydrated ethanol and 19% of E22 gasohol (gasoline with 22% of anhydrous ethanol), resulting on a fuel with 15% of gasoline was also investigated. The main difference between E85 and H81 is the water content due to the use of hydrated ethanol. As the E85 is not available in Brazil, this is the correspondent feasible mixture with commercial fuels in the country. Both fuels were assessed and compared to hydrated ethanol regarding cold start, cold driveability, speed recovery, pollutant emissions, fuel economy and deposit formation with engine and vehicle tests performed in the Petrobras Research Center (CENPES) laboratories.

On an injection mold, the runner system is divided in: main runner, secondary distribution runners and injection gates. As for the injection gates, one of the most widely used designs is the pinpoint gate, for being simple and leaving small marks on the injected part. In the literature, the authors diverge for the values for the optimization of the gate, recommending further studies for each application. On that note, the objective of this study is to analyze through CAE the values recommended for the pinpoint gate in order to obtain the optimized injection process, varying the material, shape and thickness of the product. At the end of the study, a reference chart will be presented with the gate dimensions that were the most efficient in the computer simulation for each type of part, to aid in the project of future injection molds.

The anodization process, which is characterized by forming a thin oxide layer through chemical process, contributes to increase the surface hardness where it is deposited, improving the resistance of the part in terms of corrosion and abrasion. This treatment has been applied to automotive engine pistons with the objective of improving the component durability confirmed by the observance of significant gain in terms of performance related to wear on the top hat and on the first land. With the anodized layer on the whole piston, the piston machining process has potential to be reduced, resulting in lower costs. Based on this opportunity to reduce process costs and improve component performance, this paper shows the engine validation process required to evaluate the application of an anodized layer around the whole piston.

Traffic accidents cause significant material and social losses. Reducing accidents requires actions in different fronts and involves multiple players, and is not a straightforward task. In spite of this, both in developed and also in development countries, plans are being put in place to reduce these losses. This paper discusses shortly the efforts to reduce accidents, and presents some of trends and the features that electronic modules have made possible, that are aimed to increase road safety.

SMART RRS is an FP7 SST 2007 RTD1 European collaborative project funded by the EC with the participation of 10 institutions from 5 countries. The project aims to develop a new smart road restraint system that will reduce the number of deaths and injuries caused in road traffic accidents by integrating primary and tertiary sensor systems in it, providing greater protection to all road users, warning motorists and emergency services of danger for prevention purposes and alerting emergency teams of accidents as they happen to minimize response time to the exact location of the incident. This new smart restraint system will: Reduce the number of accidents through better information on the actual state of the road and traffic flow (climatic conditions, traffic flow, obstructions, hazards, accidents). Eliminate dangerous profiles from road restraint systems (crash barriers) that currently endanger vulnerable road users.

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.

Avionics Systems are increasingly used to perform safety-critical functions at high altitudes. But their increasing capacity and concentration of memory and logics leads to more frequent occurrences of single event upsets, especially in high altitudes. In this work we discuss the process of eliciting and validating requirements to handle single events upsets in avionic systems. To do that we initially summarize and update the concepts of radiation environment of the atmosphere, radiation induced errors, single event upsets, etc. presented in a previous paper. Then, we discuss some of their effects on avionic systems and ways of mitigation, reported in the literature. Finally, we discuss provisions to demand the adoption of such mitigation measures, and their sufficiency by transforming them into requirements, according to recommendations of compliance described in standards as SAE ARP 4754A and RTCA DO-254.

The need for entertainment and information has been a desire ever since people began driving cars. Over the last decade, the entertainment systems for vehicle applications have transformed from a basic audio system to an infotainment and information center similar to what is available in the home or office. The vehicle passenger compartment has already integrated the major innovations available in the home entertainment market, such as Video, Gaming, DVD, MP3, USB, Navigation and Internet connectivity. This rapid growth has been driven by both customer demand and increased affordability. This revolution has driven major changes in vehicle design to accommodate the new concepts and features. Vehicles are now an extension of our homes and offices in terms of convenience, information and entertainment, with content delivered in a safe and pleasant manner for the driver and passengers.

Nowadays the necessity of diminish the processing time is searched incessantly in the industry in general, what it is not different for the automotive industry. The test of internal combustion engines (ICE) adds in general, a significant cost for the automobiles manufacturers due to difficulties found during the calibration of the engines[1][2]. Regarding the higher costs that involves all the process, we consider the use of Neuro-Fuzzy systems to facilitate the calibration, to diminish the running time and to avoid the using of expensive equipments by means of the introduction of a new strategy for controlling of air-fuel mixture. This strategy can describe the non linear characteristics of the ICE and adds a level of adaptability to the system, through the adjustment of its parameters by functional data of the engine[1].

It is presented in this study a methodology based on numerical simulation by means of the computational fluid dynamics for the analysis of air flow inside the engine tunnel for commercial vehicles, aiming primarily at the performance of the cooling system. The simulations have been carried out with the software Ansys CFX v12.1. Starting from the geometries of the water and engine charge air radiators, a 3D finite volume model is automatically generated for this system by means of a macro written with Excel, taking into account the dimensions, forms and quantity of tubes, as well as the fluid inside them, in order to represent the heat exchanges which occur on the water and air radiators.

The Hybrid FE-SEA method is a recently developed numerical technique that deals with the so-called mid-frequency problem. Such problems involve the dynamic analysis of systems that include, at the same frequency range, components with high and low modal density. Systems with a reduced number of modes are usually modeled using deterministic methods, as the Finite Element (FE) Method, while modal dense systems need to be treated by means of statistical methods such as the Statistical Energy Analysis (SEA). Neither FE nor SEA can properly describe a system that displays the mid-frequency behavior due to a prohibitive computational cost (FE) or the lack of accuracy (SEA). The floor structure of an aircraft is a typical case of a mid frequency problem, where the floor beams are relatively rigid and have very few modes while the floor panels have a very high modal density.