A validation study of the detachable shell dyno excitation method for structure-borne road noise evaluation

Road-induced noise within a vehicle is always a relative quantity of its excitation. Therefore, automotive NVH engineers strive to keep the excitation as precise and reproducible as possible when it comes to road noise measurement. To achieve this purpose, a dyno excitation method using precision CNC-milled detachable shell is proposed and its proper operational condition for road noise evaluation is investigated in this article. The proposed dyno excitation method not only enables a highly reproducible matching excitation to the actual proving ground excitation up to 500 Hz, but also circumvents typical unfixed phase relation of the road noise input problem by applying symmetric excitation surfaces between the left and right wheel about the longitudinal axis. Additionally, the influence of the roller diameters on this excitation method is experimentally examined. (C) 2018 Institute of Noise Control Engineering.