Reduction of Sound Radiation by Using Force Radiation Modes: Effects of Attached Mass on Force Radiation Modes

摘要

The location of a vibration source within a machine is sometimes found to have a significant effect upon its radiated acoustic power. Previously, it was suggested that the radiation mode concept can be extended to understand the relationship between the acoustic power and the driving force distribution. It was demonstrated that the radiated acoustic power can be reduced by moving the driving force location to the nodes of the extended radiation modes (force radiation modes). In this paper, modification of the force radiation modes by attaching a mass is studied with the intention of moving a node to the driving force location. The results show that the force radiation modes can be modified by attaching a mass and that the mode shapes helps to determine the location of the mass which causes the sound radiation to be reduced.