近场结构声辐射模态分析

Modal analysis of structural acoustic radiation in the near field

为减小由瑞利积分计算结构声辐射功率的复杂性及结构振动模态声辐射耦合对辐射效率的影响,提出以有限离散思想为基础的结构近场声辐射模态分析方法,该方法对结构辐射表面进行离散化,利用叠加原理建立近场声辐射模态模型和辐射声功率的计算公式。以简支板为例,利用有限元和边界元法对近场结构声辐射进行仿真分析,计算了结构声辐射模态,辐射效率,声功率及场点声压等声场特性参数,并讨论了不同力作用位置对结构声辐射的影响,得到了简支板结构在简谐激励力作用下的近场声辐射特性。该分析对复杂结构声的近场声辐射仿真计算和主动控制有重要指导意义。

In order to reduce the complication of the solution of acoustic radiation power by the rayleigh integral and avoid the effect of structural acoustic mode coupling on the acoustic radiation efficiency, the new method is presented. The approach computes acoustic radiation mode in the near field based on the finite discrete theory. Numerical example of the modal analysis of acoustic radiation of plate with the simple boundary is given. A modal analysis model of plate acoustic radiation in light fluid based on the finite element method and the boundary element method is proposed for calculating acoustic radiation mode, radiation efficiency, sound power and nearfield pressure. The characteristics of structural acoustic modal radiation of plate are shown. The analysis will benefit the simulation and control of the complex structural acoustic radiation.