摘要
通过采用边界积分方法并结合水声无源材料自由场测试等工程实际,对几种典型复合边缘结构形式的水下扁平结构的散射声场分布规律开展了进一步地研究与分析。在此基础上,尝试在不改变主体扁平矩板结构声学性能的前提下,提出通过附加边缘结构设计即物理解决途径上对自由场测试中存在的边缘效应进行抑制或去除,为提高测试精度(尤其是低频段测试精度)创造条件,也为边缘效应抑制机理和技术的研究与开发奠定基础。数值仿真与理论分析结果表明:1.复合附加边缘矩板结构的散射声场频域分布特性与多数附加边缘类型扁平矩板结构散射声场分布的总体规律基本一致,在趋势上是相似的,而边缘重数的增加加剧了前向散射与镜向散射声场间的差异性和不同程度地增大了声场的波动程度;2.附加边缘声学结构设计(如共振吸声结构或软表面声学处理、增加有效边缘重数等)对抑制结构边缘效应负面影响是有效的和可行的,且具有较好的可控性。
In this paper, the characteristic of scattering field distribution for underwater flat structure with multiple edge shape is investigated and analyzed in detail based on the Boundary Integral Method （BIM） with taking into account practical engineering application, for instance, free field measurement for underwater acoustic passive material. And then in the condition of keeping acoustic performance of the main body of underwater flat and rectangular panel structure, appended edge shape design, which is whole physical settled way, is put forward in order to suppress and remove the influence of the edge effect originated from sample panel and component. It is in favor of improving the measurement precision and researching and developing the technique and mechanism of suppressing edge effect. The numerical simulation and theoretical analysis results are shown that： （1） the rule and trend of the scattering field distribution for underwater flat structure with multiple edge shape in the frequency domain is basically in agreement with a great number of the types of appended edge shape, and the difference between the forward scattering and backward scattering is enhanced to some extent by increasing the layer number of edge, and so does the fluctuant extent of the acoustic field. （2） The acoustic design of appended edge shape, such as resonant structure of sound absorption, the treatment of soft surface and the addition of layer number of edge layer etc., is helpful to reduce the negative influence of edge effect, and it is controlled lightly.
出处
《声学技术》
CSCD
2009年第6期734-741,共8页
Technical Acoustics
关键词
水下扁平结构
散射声场
边界元法
复合边缘结构
underwater flat structure
scattering acoustic field
Boundary Integral Method （BIM）
multiple edge shape
