Effect of Phase Staggering Exterior Noise Sources on Acoustic Levels

Noise generated by tracked vehicles is influenced by dynamic forces generated during suspension and track interaction. The forces cause the suspension components on the exterior of the vehicle, such as road wheels and drive sprockets, to ring at resonant frequencies. A portion of the interaction forces propagate through the suspension and into the vehicle chassis, where they radiate both exterior and interior noise from vehicle panels. This paper demonstrates these phenomena using an example based on a hypothetical tracked vehicle. The results show that staggering the phase between the excitation forces generated by the track and suspension has a significant effect on the exterior acoustic levels and radiation patterns. The interior acoustic levels can also be reduced significantly.