结构振动模态耦合对辐射声功率的影响  

Effect of Structural Modal Coupling on Total Radiated Sound Power

作　　者：李双[1] 陈克安[1] 

机构地区：[1]西北工业大学航海学院,西安710072

出　　处：《机械科学与技术》2007年第11期1390-1393,共4页Mechanical Science and Technology for Aerospace Engineering

基　　金：国家自然科学基金项目(10274060)资助

摘　　要：定量研究了结构振动模态耦合对辐射声功率的影响。首先利用结构振动模态的叠加性,基于辐射声功率的二次型表达式,将总的声功率分解为各个模态自身辐射的声功率和模态间的耦合对声功率的贡献两部分;然后引入声辐射模态,得到一般结构模态间的耦合对声功率贡献的通用数学表达式。研究结果表明:在中低频范围内,振动模态间的耦合对辐射声功率的影响由振动模态的幅度大小、振动模态间的相位差以及振动模态与低阶辐射模态向量的内积等因素决定;以矩形平板为例进行了分析,并讨论了模态耦合问题在结构声辐射有源控制中的应用,最后进行了计算机仿真实例分析和验证。Using the structure modal superposition method and the quadratic form of radiated sound power, we divide the total sound power into the two parts ： the sound power radiated by each individual mode and the sound power contributed from modal coupling. Then with the acoustic radiation mode, we derive the general-purpose expression that determines the contributions of modal coupling to a structure＇s total radiated sound power. Finally, taking a rectangular panel for an example, we discuss the application of modal coupling to the control of a structure＇s sound radiation from a certain source. The results show that within medium and low frequency ranges, the effect of modal coupling on radiated sound power depends on the amplitude of vibrational modes, their phase difference, and inner products from low-order radiation mode vectors.

关 键 词：辐射声功率 模态耦合 声辐射模态 

分 类 号：TB53[理学—物理]