流固耦合声子晶体管路声振特性及减振降噪研究

Fluid-structure interaction (FSI) piping systems are widely applied in industrial and military fields, where the requirement of vibration and noise reduction is extremely urgent. The vibration and acoustic properties of the FSI pipe are more complex because the vibration, flow noise and acoustic radiation couple with and influence each other. The bandgaps in Phononic Crystals (PCs) can effectively control the propagation of vibration and sound, which provides a new idea for the vibration and noise reduction. The current project will introduce the theory of PCs into the vibration and noise reduction design of FSI pipe systematically. An intensive study of the vibration and acoustic properties of the PC pipe will be carried out under the complex FSI conditions, as well as the coupling of acoustic and vibration. Finally, we will accomplish the design of vibration and noise reduction for the FSI pipe basing on the PC theory. In this project, we are planning to investigate the following aspects: An intensive study of the vibration bandgap properties of the FSI PC pipe, and overall consideration of the vibration stability and dynamic stress concentration properties. Investigation of the properties of flow noise in the pipe, structure-borne radiation of pipe wall and noise radiation of pipe openings. Research of the coupling and influence between the vibration and noise of the FSI PC pipe. Design and improvement of the experimental system, and completion of the experimental test and verification. Optimal design of vibration and noise reduction of the FSI PC pipe. The project research results are expectd to provide a new theoretical foundation and technical support for vibration and noise reduction of the FSI pipe.

流固耦合管路系统广泛应用于工业及军事领域中，减振降噪需求迫切。流固耦合管路中的振动、流噪声以及声辐射相互耦合与影响，声振特性复杂。声子晶体的带隙特性可以有效控制振动与声的传播，为减振降噪设计提供了新思路。本项目将声子晶体理论系统引入到流固耦合管路减振降噪设计中，深入研究复杂流固耦合条件下声子晶体管路的声振特性以及声振耦合，实现基于声子晶体理论的流固耦合管路减振降噪设计。项目将深入研究流固耦合声子晶体管路的振动带隙特性，同时兼顾振动稳定性与动态应力集中特性；研究流固耦合声子晶体管路内流噪声传播特性，管壁结构的结构声辐射特性以及管路开口处的噪声辐射特性；研究流固耦合声子晶体管路声振耦合与影响关系；设计与完善管路实验系统，完成实验测试与验证；研究流固耦合声子晶体管路的减振降噪综合优化设计。项目研究成果有望为流固耦合管路系统减振降噪设计提供新的理论基础与技术支持。

流固耦合管路系统广泛应用于工业及军事领域中，减振降噪需求迫切。流固耦合管路中的振动、流噪声以及声辐射相互耦合与影响，声振特性复杂。声子晶体的带隙特性可以有效控制振动与声的传播，为减振降噪设计提供了新思路。本项目将声子晶体理论系统引入到流固耦合管路减振降噪设计中，实现了基于声子晶体理论的流固耦合管路减振降噪设计。本项目主要内容及结论如下：.1．深入分析了声子晶体管路振动带隙特性。研究了复杂结构形式、复杂边界条件、复杂激励条件下的振动带隙特性；研究了声子晶体管路振动稳定性；分析了功能阶梯材料的应力分布的影响。.2．深入研究了声子晶体管路噪声特性。研究了周期扩张管、Helmholtz共振器以及组合等结构形式的带隙特性；分析了管路开口处的噪声辐射特性。.3．开展了流固耦合声子晶体管路声振耦合与影响分析。分析了流固耦合声子晶体管路振动与噪声之间的耦合与影响关系；研究了声振耦合对管口声辐射的影响。.4．开展了流固耦合声子晶体管路减振降噪综合优化设计。基于声子晶体管路声振影响关系，统筹振动、流噪声以及声辐射特性，综合优化设计了相应的管路系统；形成流固耦合声子晶体管路系统减振降噪综合设计方案，实现了声振综合控制。.5．完成了流固耦合声子晶体管路实验测试与验证。设计与完善了管路实验系统，声振综合测试，完成了基于声子晶体带隙理论的流固耦合管路减振降噪原理性验证。.总之，本项目研究为流固耦合管路系统的减振降噪综合设计方面提供了新的理论基础和技术途径。