声激励位置对简单导管声辐射特性的影响

文章借助NASTRAN软件，研究了单极子和偶极子声激励位置对简单刚性导管声辐射特性的影响。结果表明：（1）声源的径向位置对导管声辐射影响大，而轴向位置影响小，声源越靠近导管壁，辐射声功率峰值越大；（2）对于单极子而言，声源偏离径向中心位置时，声场的对称性取决于声源的频率值；（3）偶极子声源的方向对于导管声辐射特性的影响很大，必须加以考虑。

Influence of Excitation Location on Sound Radiation of a Simple Duct Excited by Sound Source

Using a method based on NASTRAN infinite element technology, this paper studied the influence of excitation location on sound radiation of a simple hard duct excited by monopole and dipole source. The results show that: (1) The radial location of source has great influence on the sound radiation of duct, while the axial location does not. As the source moves towards duct wall, the radiation power becomes higher. (2) The symmetrical characteristic of sound field contours de-pends on the source’s frequency when a monopole moves towards the duct wall. (3) The orientation of dipole has a significant impact on the sound radiation of duct, which must be ignored.