Effect of Intentional Dry Friction Damping on the Performance of an Elastomeric Engine Mount

Abstract

Automotive engine mounts are used to protect engine from road irregularities and to isolate transmission of vibrations created by the engine which have a drastic effect on the noise generated inside the passenger cabin. Most common types of engine mounts are elastomeric and hydraulic mounts, the former having better vibration isolation characteristics whereas the latter displays better shock isolation. Elastomeric mounts are widely used for their low initial cost, while hydraulic mounts with inertia track and decoupler are chosen for their good vibration isolation and shock excitation characteristics. However, hydraulic mounts with inertia track and decoupler are not appropriate for small segment and commercial vehicles due to their high initial cost. In this paper, the effect of the addition of a dry friction damper on the performance of elastomeric automobile engine mounts is investigated. Results showed that addition of dry friction damping to the elastomeric engine mount significantly improves the transmissibility throughout a wide frequency range where the best results are obtained at the resonance frequency.