Experimental evaluation of crucial noise and vibration metrics for engine mount

A multi-objective experimental evaluation method concerning the crucial noise and vibration metrics for engine mounts was developed to provide the trade-off guidelines. We illustrated the noise, vibration, and harshness (NVH) design requirements for rubber engine mounts. Three mount stiffnesses for front mounts were used for development testing according to the results of dynamic analysis. Powertrain rigid body modal validation showed that all three mounts met the powertrain bounce frequency target. The experimental modal results were in a good agreement with the dynamic analysis predictions. The dynamic force validation showed a first promising step toward good design for NVH. Because the single performance of dynamic force was not appropriate for the comprehensive mounts development, we defined a combined NVH performance of an engine mount as the sum of five weighted individual crucial metrics concerning the mount attenuation, idle NVH, interior noise, secondary ride and subjective assessment. The weighting factors were set according to the local driving environment. We proposed the term “normalized integration area” to efficiently identify the mount performance of isolation and interior noise. Based on the evaluation method developed, we identified the trade-off mount specification for the application case.