Predicting noise, vibration and harshness performance degradation through fatigue analysis

Abstract

Vehicle performance from a noise, vibration and harshness (NVH) perspective is typically evaluated at zero mileage. As the vehicle accumulates miles, systems that are considered as NVH sources and systems that are part of a noise and vibration path tend to see some degradation due to loosened joints, burnished gears, burnished bearings, etc. Up to date, efforts made to understand and predict NVH performance degradation are very limited. NVH degradation is not usually caused by a hard failure, such as cracks or bends; it is rather produced by fatigue degradation. In this work, we review the main literature written in the area of reliability performance degradation caused by fatigue. We evaluate how the same methods can be used for NVH degradation evaluation. We also introduce a new method to evaluate NVH degradation through damage analysis based on bench testing and stress-life curves.