Damper arrangement to reduce structure born sound based on structural intensity

Abstract

Vibration measures can be taken at three main locations: the vibration source, the propagating part, and the radiating part. However, implementing measures at the vibration source is often challenging, and countermeasures at the radiating part are inefficient. Therefore, measures taken at the propagation part are typically preferred. To achieve this, the technique of structural intensity (SI) is commonly used, which is effective in understanding the propagation path. In this paper, we propose reducing vibration using a viscous damper layout based on the SI distribution at the propagation part. We present the most effective layout for vibration reduction in a 3 degree of freedom (DOF) system. Our results show that adding a damper on the response side is effective. Additionally, we discuss the relationship between the ratio of change of SI and velocity for a flat plate. Based on these findings, we propose a new method for identifying the damper location by SI. The method involves determining the location where the spatial rate of change of SI is highest in the path from the excitation and response points. We verify the effectiveness of our proposed method on a flat plate and demonstrate its effectiveness on an automobile body for vibration reduction.