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Studies aimed at partial or total use of renewable fuels in diesel engines has increasingly attracted the interest of the automotive industry, in particular due to its characteristics of strength, durability and greater thermal efficiency. The oil esters derived from biological sources, who receive the generic name for biodiesel, is one of the alternatives used internationally. Their physicochemical properties are similar to diesel oil for providing an acceptable dynamic process of preparation and combustion in the engine. This paper presents and evaluates the results of experimental tests carried out in four trucks used exclusively B20 biodiesel (20% biodiesel and 80% petroleum diesel), and one with B100 (pure biodiesel), in real operating conditions.

Vehicles manufacturers, in search of cost reduction, fill the tanks of recently manufactured vehicles with the least volume of fuel necessary for future commercialization. The adoption of such practice, depending on the diesel fuel storage conditions, may lead to oxidation products formation in the fuel system and to problems during the first start of these vehicles. Some vehicles manufacturers, trying to minimize the occurrence of these problems, replace the diesel fuel in the vehicle tank with new fuel when vehicle storage time reaches 90 days. As a result of such occurrences, the opportunity for a first fill diesel fuel development, that presented better oxidation stability during storage, was identified. In the first stage of the special diesel fuel development, various analyses where conducted in laboratory, in the sense of defining criteria for the fuel formulation, taking into consideration the chemical variability of commercial Brazilian diesel fuel type A and biodiesel.

In engineering development, simulation methods are frequently used to perform thermal and mechanical stress components analysis. In brake systems, where the components are exposed to mechanical and thermal loads, the numerical analysis is very helpful. Once a numerical model for brake assembly is available, it will be possible to understand the effects of successive brake applications on the temperature distribution in drum brake's friction materials. This is a fundamental aspect to determine, for instance, the thermal stress distribution which is related to the warming and cooling of the brakes. In this work, an analytical solution to calculate stabilized temperature was used to establish a heat flux through a pneumatic S cam drum brake's friction material applied to a numerical model in a finite element analysis.

With the constant evolution of vehicle systems becomes increasingly challenging the Components project. The demand for mass and cost optimization in a challenging project schedule scenario generates a great challenge to the engineering teams, who look for design and development methods more assertive. In order to reduce the risk of failure, testing time and design cost, simulation tools are being increasingly used. A major challenge in the component project for trucks and buses is the knowledge of the real loads that the components are subjected. In the case of propeller shaft bearings several factors should influence the magnitude of the efforts. The biggest influent factors that has been studied and discussed widely for many years are the torque and joints angles.

Simulations tools like AVL Cruise and Vehicle Dynamics where used to carry on a comparative study between two trucks equipped with automated manual transmissions in two configurations: the original with 12 gears, and a proposal with 16 gears. The original configuration is world-wide used and in this way, the present study was fundamental to decide whether choosing the new proposal would bring the Brazilian option any advantages. In order to evaluate the whole vehicle behavior fuel consumption evaluation and vehicle performance were analyzed. From the present study, it was showed that the 16 gears transmission was the best alternative for the Brazilian application.

Evaluation of vehicle performance is one of the most important phases of the new vehicle development. Start Ability and Top Speed are factors that are noticed by users, therefore are very important to the final product. Vehicle performance evaluation has been largely benefited from the use of simulation tools. In fact, MAN Latin America (ML) employs simulation programs to evaluate the performance of its vehicles (trucks and buses) achieving good results. However, those programs are normally “closed codes” which makes difficult the physical comprehension of results. Altogether, this article presents Vehicle Dynamics, a macro developed by ML engineering team. The aim of this macro is the automatic calculation of Start Ability, Grade Ability, Top Speed, among other performance parameters.