阶梯型圆盘的指向性及相关因素研究

Study on the directivity and its relevant factors of the flexural vibrating stepped-plate

针对自由边界条件的阶梯圆盘,以带有一个上凸的阶梯为例,将盘面视为中心盘面和圆环面两部分组成,利用瑞利积分、声场迭加的方法,对阶梯盘的指向性进行计算,计算结果与Gallego测试的结果相吻合.进一步分析了阶梯盘指向性与材料、基底厚度等之间的关系.结果表明:指向性与阶梯盘材料关系并不显著;在相同谐振频率下,随着阶梯盘基底厚度的增加,主瓣的指向性将越尖锐,同时副瓣也变得窄细、尖锐.

The stepped plate can be divided into two parts by the nodal circle, one is the inner plate, and the other is the ring cycle plate. The radiated acoustic field directionality of a flexural vibrating circular plate with one raised step under free boundary is calculated by using Rayleigh integral and acoustic superposition method in this work. The calculated results agree with the Gallego experimental test results. Furthermore, the directionality related with materials and the base thickness are also investigated. It can be found that the directivity is independent on materials. Under same resonant frequency, with the increase of base thickness the main lobe is sharper and the side lobe also becomes narrower and sharper.