Abstract
Keywords:Diesel engine, radiated noise, computational analysis, NVH
Aim of this paper is to focus on the contribution of computational analysis to the achievement of stringent NVH targets. On one side several simulations have been performed to verify that the minimum powertrain bending natural frequency is met, as well as that accessories fundamental natural frequency is above the specific target. On the other side, forced response analysis have been run in order to optimize the main components, so that a lot of attention has been paid to the design of the engine block, the bedplate, the upper part of the oil pan, the engine timing cover and cylinder heads. Numerical results in terms of surface vibration levels due to forced excitation have been compared to scatter-band data available for similar diesel engines: this allowed identifying critical areas where additional stiffening was recommended to reduce radiated noise as well as those areas where a potential mass saving is applicable.