对两相材料薄板声功率及其灵敏度研究

采用有限元与声辐射模态相结合方法研究两相材料薄板声辐射声功率,并分析结构声功率关于设计参数的灵敏度。应用有限元方法来处理结构的振动环节,将位移向量用振型的线性组合表示,用振型叠加法求解模态坐标得到位移向量从而求出结构的速度分布;在声辐射环节,采用声辐射模态展开从而求得声功率。将薄板声功率对设计参数求偏导,得到声功率灵敏度。以四边简支两相材料薄板为例,着重对声功率关于板密度和厚度的灵敏度进行了研究。

Analysis of sound power and sensitivity of bi-material thin plate

In this paper, the sound power and sound radiation sensitivity of bi-material thin plate is studied by using FEM and sound radiation mode method. On the aspect of the structure vibration solved by FEM, the displacement vector is regarded as a linear combination of the modals, and using modal superposition method solves the modal coordinates to get the displacement vector and the velocity distribution of the structure;on the aspect of sound radiation, the sound power is obtained by the expansion of the acoustic radiation modes. The sound radiation sensitivity is defined by the partial derivatives of sound radiation power with respect to design variables. Taken a simple supported bi-material thin plate as a simulation example, the sound power sensitivities to the distribution density and thickness of the plate are investigated.