利用源强密度声辐射模态重建声场

Acoustic field reconstruction using source strength density acoustic radiation modes

为了利用声场中少量测点声压数据精确重建复杂结构的辐射声场,提出了源强密度声辐射模态分析理论和声场重建公式.在结构表面定义的空间上,利用以源强密度分布函数为参量的结构辐射声功率泛函表达式定义了一个线性自伴正辐射算子,该算子的特征函数为结构的源强密度声辐射模态.然后通过对矩形平板和带有半球帽的圆柱体的源强密度声辐射模态的分析,证明了源强密度声辐射模态具有空间滤波特性,并利用该性质建立了声场重建公式.球体仿真和平板实验验证了所提出的声场重建方法的可行性和稳健性.基于源强密度声辐射模态的声场重建方法简单,利用较少测点数据就可以获得较高的声场重建精度,特别适合于复杂结构的低频声场重建.

To use a small number of acoustic pressure measurement data to reconstruct the radiated acoustic field of the complicated structure, a theory of source strength density acoustic radiation modes is proposed and a formula of acoustic field reconstruction is developed. In the space defined on the surface of the structure, functional form of the acoustic radiation power expression in which parameter is source strength density is constructed. In terms of the functional a linear self-adjoint and positive radiation operator is defined whose eigenfunctions are source strength density acoustic radiation modes. And then it is proved that source strength density acoustic radiation modes possess space filter characteristic through analyzing the source strength density radiation modes of rectangular plate and cylinder with hemisphere ends. The formula of acoustic field reconstruction with the space filter nature is obtained. The sphere simulations and plate experiment validate the feasibility and robustness of the proposed acoustic field reconstruction method. The acoustic field reconstruction method based on the proposed radiation modes is simple, has high accuracy that can be obtained by using only a few measurement data, so this method is especially applicable for low frequency acoustic field reconstruction of the complicated structure.