Role of Dynamic Stiffness in Effective Isolation
Published June 5, 2019 by SAE International in United States
Annotation of this paper is available
In any machinery, avoiding noise and vibration completely is a difficult task due to the structural dynamic behaviors of components. To safeguard the operator, it is important to best isolate the operator station from NVH environment. Cabin isolation is an important aspect to minimize structure borne noise and tactile vibrations to be transferred into the cabin. Isolators are selected based on the isolation system inertial properties at mounting locations in the operating frequency range interested. The most important assumption to select isolators are that the active side and passive side of the isolators are nearly rigid so impedance mismatch is created for effective isolation.
This paper describes the importance of dynamic stiffness of the structures on both the active and passive side for better NVH performance. NVH performance of passive side is evaluated analytically and computationally in terms of tactile vibrations and structure borne noise for various ratios of the dynamic stiffness over isolator stiffness. The isolator selection criterion is also discussed based on rigid body modes, operating frequency range, transmissibility ratio, and kinematic energy distributions.
CitationDasabai, B. and Yang, Y., "Role of Dynamic Stiffness in Effective Isolation," SAE Technical Paper 2019-01-1495, 2019, https://doi.org/10.4271/2019-01-1495.
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