Currently, new technologies in automotive industry are mainly driven by CO2 regulation and fuel economy. For most of the OEMs, the priority is to optimize internal combustion engines, make light-weighting and develop hybrid vehicles or fully electric vehicles. In this context, it is difficult and expensive trying to reach absolute silence in the cars. A good NVH strategy for non-specialist OEMs will be to keep the noise to an acceptable level and make it as homogenous as possible.
This article presents several NVH guidelines for the powertrain in order to achieve homogenous noise in the cars. Firstly, master the level of powertrain vibration and maintain it at a suitable level. Secondly, eliminate abnormal noises which are unpleasant and disturbing, such as transient Diesel clatter noise. Thirdly, reduce the levels of emerging noises from powertrain components, such as turbo charger whistling so that they can be masked by background noise. For each guideline, examples of concrete NVH problems are described and optimization methodologies are presented.