声功率极小值的产生机理分析  

Mechanism analysis of the generation of radiated acoustic power minimum

作　　者：史英沙 黎胜[1,2] SHI Yingsha;LI Sheng(State Key Laboratory of Structural Analysis,Optimization and CAE Software for Industrial Equipment,Dalian University of Technology,Dalian 116024,China;School of Naval Architecture and Ocean Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学工业装备结构分析优化与CAE软件国家重点实验室,辽宁大连116024 [2]大连理工大学船舶工程学院,辽宁大连116024

出　　处：《哈尔滨工程大学学报》2024年第11期2084-2093,共10页Journal of Harbin Engineering University

基　　金：国家自然科学基金项目(11772080).

摘　　要：针对结构辐射声功率极小值产生机理尚不明确的问题,本文基于振动模态耦合声功率的正负对矩形板结构的辐射声功率极小值进行了研究。结合声辐射模态对结构振动模态的辐射效率进行了分析,研究了结构在不同流体介质中辐射声功率极小值的特性差异及其产生原因。结果表明:声功率极小值的产生主要与振动模态耦合相关,低阶奇-奇振动模态之间的耦合对声功率极小值有较大贡献。在本文中激励频率在第5到第6阶共振频率之间,第5、6阶振动模态耦合的声功率为负时,会较大降低矩形板的辐射声功率;水中矩形板的低阶奇-奇模态辐射效率高,模态耦合可以极大降低结构的辐射声功率并出现极小值。Addressing the unclear mechanisms behind the minimum structural radiation sound power,this paper ex-amines the radiation sound power minimum of rectangular plate structures by focusing on the positive and negative of the acoustic power of modal coupling between vibration modes.Acoustic radiation modes are used to analyze the radiation efficiency of structural vibration modes.The study investigates the difference in the minimum radiated a-coustic power from a vibrating plate when placed in different fluid media and explores the underlying causes.It re-veals that the minimum radiated acoustic power is mainly influenced by the cross-coupling between structural vibra-tion modes,with significant contributions from the coupling between lower-order odd-odd vibration modes.Specific-ally,the study finds that when the excitation frequency falls between the 5th and 6th order resonance frequencies and the acoustic power coupling of these modes is negative,the radiated acoustic power of the rectangular plate will be greatly reduced.The radiation efficiency of the lower-order odd-odd modes of the rectangular plate are high in water,and the modal coupling can greatly reduce the radiated sound power up to the minimum.

关 键 词：声功率 极小值 振动模态 声辐射模态 模态分析 模态耦合 辐射效率 激励位置 

分 类 号：TB532[理学—物理]