Layout Method of Damping Material for Gearbox Based on Acoustic Contribution

Abstract

In order to realize the low noise design of marine gearbox, a layout method of damping materials for gearbox based on acoustic contribution was proposed. The present method can accurately and effectively determine the additional area of damping materials and achieve greatly the noise reduction effect. Firstly, taking a marine single-stage herringbone gearbox as the object, the finite element/boundary element model for the reducer structure was established. After applying the vibration excitation of the gear system, the radiated noise of each field point was solved. Secondly, by analyzing the acoustic transfer vector (ATV) and modal acoustic contribution (MAC), the surface of the gearbox was partitioned, and the partitioned surface was analyzed by using panel acoustic contribution (PAC). Finally, the damping material was added to the plate area which contributes greatly to the radiated noise, and the effect of the noise reduction under different schemes were compared. The results show that the layout design of damping materials based on the present method can reduce the radiation noise of observation points accurately and effectively in the range of 0~4 000 Hz.

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