任意边界条件下具有声学混合界面的声振耦合空间系统传递特性研究

The main reason for the noise produced in ship cabin is the vibro-acoustic transmission of acoustic mixed interface. For the acoustic mixed interface inside the cabin, the lack of the overall study on the structure sound transmission caused by the vibration of elastic structure and the opening sound transmission produced by the energy exchange property for the acoustic transparent opening, restricts the theoretical development and technological innovation of vibro-acoustic transmission problem. The purpose of this thesis is to establish a vibro-acoustic coupled spaces system theoritical model with an acoustic mixed separation under arbitrary bondary conditions, and on this basis, the theoretical calculation and experimental verification are carried out to study the space field distribution characteristics, the regularity of sound transmission and the coupling mechanism in the vibro-acoustic coupled spaces system.Thereinto, the acoustic analysis of coupled aperture is developed based on the acoustic transparent property and energy exchange property for the coupling aperture; The vibration analysis model of structure with an opening is established based on energy principle; Based on the structural acoustic coupling relation, the acoustic transmission problem analysis method for the vibro-acoustic coupled spaces system is established; Through the investigation on the effect of the acoustic impedance boundary, the elastic structure boundary, the size and position of the opening on the sound field distribution characteristics in the vibro-acoustic coupling space systems, to reveal the regularity of sound transmission and coupling mechanism for the vibro-acoustic coupled spaces system.To provide the analysis method and theoretical support for the prediction for ship cabin acoustic transmission.

声学混合界面声振传递问题是船舶舱室噪声产生的主要原因。对于舱室内部的声学混合界面而言，缺乏同时考虑由弹性结构振动引起的结构声传递和声学透明开口能量交换性导致的开口声传递的整体研究，制约了声振传递问题的理论发展与技术革新。本课题旨在建立任意边界条件下具有声学混合界面的声振耦合空间系统理论模型，并在此基础上通过理论计算和实验验证研究声振耦合空间系统声场分布特性、声传递规律及耦合机理。其中，考虑耦合开口声学透明性及能量交换性形成耦合空间声学分析理论；基于能量原理建立带开口结构振动分析模型；通过结构-声耦合关系，建立声振耦合空间系统声传递问题分析方法；通过研究声阻抗边界、弹性结构边界、开口大小和位置等因素对声振耦合空间系统声场分布特性的影响，揭示声振耦合空间系统声传递规律及耦合机理。为船舶舱室声传递预测提供分析方法和理论支撑。

声学混合界面声振传递问题是船舶舱室噪声产生的主要原因。在考虑声学开口的能量交换性、声学“透明性”、开口大小任意性基础上，建立耦合空间声学分析理论, 预测矩形耦合空间、L型耦合空间、T型耦合空间固有频率及振型，分析声学开口尺寸和位置对耦合空间系统模态的影响，为声振耦合空间声学理论研究提供理论基础。从能量角度建立带开口结构振动分析模型及任意边界条件下具有声学混合界面的声振耦合空间系统理论模型，分别预测不同开口结构边界、开口位置条件下开口结构及具有声学混合界面的声振耦合空间系统模态特性，所建立的声振耦合空间理论模型同时考虑声学混合界面处声传递路径及结构传递路径，为声学舱室内振动噪声问题研究提供理论参考。通过理论分析、数值仿真及试验手段分析声阻抗对耦合空间声场特性的影响，研究开口结构边界、开口位置及开口尺寸对声振耦合空间系统声传递的影响，获悉声振耦合空间内声学混合界面处声传递规律，探究开口结构与耦合声场之间耦合关系，为船舶舱室声传递预测提供分析方法和理论支撑。