通过声辐射模态研究结构声辐射的有源控制

以简支平板为例,通过声辐射模态建立了弹性结构声辐射的有源主动控制策略。并分析了声辐射模态的数学和物理意义。研究发现在中、低频时,声辐射模态对应的辐射效率随着模态阶数的增加而迅速降低。在此基础上,本文提出了一种新的控制策略,即抵消前k阶声辐射模态的伴随系数,使得前k阶声辐射模态的声功率为零。本文以点力作动器作为控制力源进行了数值计算研究。

Research active structural acoustic control by radiation modes

Based on the radiation modes, it is presented an active control strategy for sound radiation from elastic structures with an example of simply supported rectangular panel. The physical characteristics and mathematical meaning of the radiation modes is analyzed. The radiation efficiency of the radiation modes falls off very rapidly with increasing modes order at low frequency. A new control strategy is developed in which by canceling the adjoint coefficient of the first k radiation modes, the sound powers of the first k radiation modes is zero theoretical. The numerical calculation is made by using point force actuators as control forces.