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The primary belt drive is required to synchronize the crankshaft and camshaft of internal combustion engines, keeping the belt tensioned. In order to provide optimum setting of the belt force (compensation of fluctuations in the belt force due to temperature, wear or dynamic effects) automatic belt tensioning system is used, nevertheless, the components of such systems are liable to high dynamic loading condition. Oscillatory loading and noise arise from the engine internal combustion and primary belt drive components can present failures even with conservative designs concerning to static loading. This paper intends, by means of numerical methods, such as Finite Elements Method (FEM) through the commercial software Abaqus, analyze the dynamic behavior of critical components of the primary belt drive system, in order to avoid failures due to dynamic excitation and resonance.

To overcome the proposals concerning to the reduction of the fuel consumption and gases emissions required by the regulatory councils around the world, but also required by the actual market, since economic vehicles have been more valorized than ever, the automotive industry have dispended considerable efforts in the development of new technologies, such as hybrid cars, and in the improvement of the current projects. Friction of any magnitude retards the motion and results in energy loss, causes temperature increase and should be reduced in order to improve the system efficiency. This paper intends, by means of analytical calculation based on dynamic systems and comparisons with Finite Elements Analysis, propose a robust method to analyze friction losses in automotive mechanical systems. Transmission application was chosen to conduct this analysis.

Dual Clutch Transmissions have conquered an important fraction of the market, mainly in Europe, as a result of their improvements concerning efficiency. Once the power flow from engine to the transmission is not interrupted, fuel efficiency increases radically. Furthermore, extreme fast and soft shifts provide the most dynamic and smooth acceleration of any vehicle on the market, being particularly suitable on high performance vehicles. The drivers have also experienced singular comfort, since they can choose whether to control the shifting or let the computer do it automatically. Nevertheless, to overcome the elevated requirements imposed to the system components, in special the release bearings, the industry has dispended considerable efforts on the development of new processes and design methodologies.