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This work describes the development and use of the Hardware-in-the-Loop (HIL) technique to evaluate the dynamic behavior of a torsional vibration rubber damper (TVD) used in a spark ignition internal combustion engine. The TVD was adapted to a test bench designed for this research and the HIL technique was applied considering the simulated dynamic response of the crankshaft. The results of the torsional vibration amplitudes are compared with measured values in a steady-state well identified condition, to experimentally validate the proposed mathematical model and the possibility to use the HIL technique to evaluate dampers and crankshaft behavior in realistic long term tests, where the rubber degradation also affects the dynamic response of the system. Finally, it was concluded that simulated and measured signals presented a good correlation in some engine operational conditions, reaching the objectives of this study.

This paper presents the comparison of two different approaches for crankcase structural analysis. The first approach is a conventional quasi-static simulation, which will not be detailed in this work and the second approach involves determining the dynamic loading generated by the crankshaft torsional, flexural and axial vibrations on the crankcase. The accuracy of this approach consists in the development of a robust mathematical model that can couple the dynamic characteristics of the crankshaft and the crankcase, representing realistically the interaction between both components. The methodology to evaluate these dynamic responses is referred to as hybrid simulation, which consists of the solution of the dynamics of an E-MBS (Elastic Multi Body System) coupled with consecutive FEA (Finite Element Analysis).

This Paper presents a study of weight reduction in an exhaust manifold of a four cylinders, 3.0 liters Diesel engine. The mass of the entire engine shall be reduced from the current 290kg to 260kg and many components will be redesigned focused on this target. Basically, the wall thickness and flanges of the exhaust manifold will be redesigned and reduced to a value which shall guaranties the component durability. The calculations will be made determining the life cycle of the proposed exhaust manifold, checking if no structural problems can occur. The shape and size of the ducts remain unchanged for performance purposes and no material changes will be considered for the new component.