Chamshaft Vibration Characteristic Assessment when Applying Needle Roller Bearings as Solution for Efficiency Increase 2012-36-0628

One of the steps towards higher efficiency internal combustion engines (ICEs) is the application of new improved subsystems, with lower power consumption. One of such subsystems is the needle roller bearing valvetrain, where rolling bearings replace the common sliding bearings designs as camshaft supports, hence decreasing the frictional torque and increasing liquid power at the crankshaft. However, the first question to arise is the vibration characteristic of the system for the new design. In order to initiate the assessment of the vibration behavior of the camshaft, some fundamental investigations should be made, such as natural frequency identification. For that, one might benefit from virtually evaluate these characteristics via FEA / Rotordynamics algorithm, reducing the need for expensive experimental setups of the complete valvetrain. This work intends to assess the applicability of these both methods to the camshaft vibration problem. Also, experimental data are used in order to check theorical results and the validity of models.