文章从结构振动模态与声辐射模态的概念出发,研究了两端简支单层圆柱壳振动模态与声辐射模态的耦合关系。在此基础上,利用模态扩展构造一个模态滤波矩阵,从有限个结构测点测量数据中得到结构的声辐射模态参与系数,进而计算结构的辐射声功率;并利用矩阵条件数对结构测点布置数目与位置进行了研究。数值算例表明:这种测点布置方法与结构辐射声功率的计算方法是可行的,这为该领域的理论分析和工程应用提供了一定的参考。
The relationship between vibration and sound radiation of a cylindrical shell simply supported at both ends is studied from the viewpoint of the structural modes and acoustic radiation modes. After the relationships between structural modes and radiation modes are obtained, a modal filter matrix is derived, by which the acoustic radiation mode velocity can be extracted from the response of allotted measure points. The acoustic power of a structure can be calculated through a weighted sum of acoustic radiation mode velocity. Then a method for sensor placement is presented based on the condition number. In an iterative manner, the initial candidate set of sensor locations is reduced to the number of available sensors. Numerical examples show the method for sensor placement and calculating acoustic power is feasible. It can be used to estimate the acoustic characteristics of a structure in practice.