Abstract: Joint using the finite element method and acoustic radiation modal method to solve the sound power structure sheet radiation, the structure radiation sound power about the design variable sensitivity was analyzed. In the structure vibration link, surface vibration velocity was obtained using the finite element method; in the sound radiation link, the sound field information about radiation of surface vibration can be obtained by expansions of the acoustic radiation modes. For the radiation of a stiffened panel, sound power sensitivity with respect to design variable was analyzed, and the results showed that the sound power was reduced by using stiffeners when the excitation frequency was far from the natural frequency of the body, but it had negative influence and was useless by using stiffeners when the natural frequency was close to the excitation frequency.

Key words: acoustics, sensitivity analysis, finite element method, acoustic radiation mode, sound power

摘要： 联合利用有限元方法和声辐射模态方法求解薄板结构辐射的声功率，并分析结构辐射声功率关于设计变量的灵敏度。在结构振动环节，利用有限元方法对结构进行动力响应分析得到表面振速；在声辐射环节，采用声辐射模态展开获得振动表面辐射的声场信息。以加筋板结构为例，计算结构振动辐射的声功率及其关于设计变量的灵敏度。结果表明，当激励频率远离结构振动固有频率时，加筋可以降低结构辐射的声功率；而当加筋使结构固有频率接近激励频率时，加筋甚至产生负面影响，此时通过加筋降低结构辐射声功率是没有意义的。

关键词: 声学, 灵敏度分析, 有限元法, 声辐射模态, 声功率