モード励振法を用いたアクティブ遮音制御に関する研究（パワーモードによる制御メカニズムの解明および実験による検証）

摘要

This paper deals with active control of transmitted sound power of a panel subjected to an incident sound wave. Based upon modal actuation reported in previous works, this paper presents modal actuation-based control for the purpose of reducing transmitted sound power of a panel. From a viewpoint of acoustic power modes, a dominant factor in structure-borne sound, a fundamental mechanism of sound transmission power of a panel is clarified, followed by a numerical analysis. It is shown that the (1, 3) structural mode (one of the elements of the first acoustic power mode) plays an important role in the sound transmission mechanism, and hence the (1, 3) mode needs to be extracted and suppressed. For this end, three cases of actuation method are presented, control effect in terms of each control strategy being discussed. Finally, an experiment is conducted, demonstrating the significant control effect achieved by suppressing the transmitted sound power at low frequencies using the proposed method in this work.%一般に壁面の遮音性能は質量に依存し，特に低周波rn数の音を遮断するには重い構造を用いる必要がある．rnこのことは機器の軽量化の大きな障害になっている．rnそこで，軽い構造によって遮音性能を向上させるため，rnアクティブに透過音を制御する研究が行われている．