自适应声学结构中基于声辐射模态的有源控制策略

研究了结构振动模态和声辐射模态之间的对应关系,并利用该关系建立了一种新的自适应声学结构有源控制策略,即引入单个或多个次级结构抵消初级结构振动模态对应的主导声辐射模态,使得主导辐射模态的声功率最小,从而控制总辐射声功率。研究结果表明:利用该控制策略,只需引入4个次级板同时抵消结构前4阶辐射模态的声功率,即可控制结构所有振动模态的声辐射,在宽频带范围内取得满意的控制效果。

A New Active Control Strategy Applied to Adaptive Acoustic Structure

Purpose.Ref.7,whose first author is the second author of this paper, can achieve satisfactory active control performance when applied to adaptive acoustic structure,but,in practical applications,it is not possible to use it to derive simple and easy-to-implement self-adaptive algorithm.We present now a new active control strategy that can be used to derive simple and easy-to-implement self-adaptive algorithm.In the full paper,we explain our new strategy in detail;in this abstract,we just list the two topics of explanation:(1) the respective relationships between acoustic radiation modes and corresponding structural vibration modes;these relationships are derived by us using the theory of Ref.8;(2) active control strategy,whose two subtopics are theoretical model(2.1) and active control strategy based on cancellation of dominant acoustic radiation modes(2.2).We used our new strategy to make numerical calculations,whose main results are shown in Figs.4 and 5 in the full paper.The results,including main results and other results,show preliminarily that:(1) by using four secondary panels to cancel respectively the corresponding four acoustic radiation modes,the sound power of each vibration mode can be almost completely cancelled;thus we can get satisfactory control performance on the broad band;(2) both the vibration mode distribution and the arrangement of secondary panels have significant influence on control performance.