复合棒型换能器锥形前辐射头弯曲振动特性

宽频带声换能器在军用及民用上都有着广泛的应用 ,近几年来国内外都开展了一些研究工作。利用复合棒型换能器的纵向振动基频与前辐射头弯曲振动的恰当耦合 ,可展宽换能器的频带 ,前辐射头是一关键部件。本文用有限元方法计算并分析了前辐射头在水中及空气中不同边界条件下的弯曲振动特性 ,结果表明 :并非所有几何尺寸的辐射头都能激发出弯曲振动来 ,两端自由时和螺栓端固定时 ,弯曲振动基频与辐射头厚度的关系恰恰相反。

On the Flexural Vibration Characteristics of the Head of a Compound Bar Transducer

Wide band acoustic transducers are widely used in military and civil applications. The band of the compound bar transducer can be widened by mode coupling between the longitudinal piston mode and flexural mode of the head in the multimode broadband design, and the head is the most critical part. In this paper, the characteristics of the flexural vibration of the head is analyzed for in-air and in-water situations by using finite element method under different boundary conditions. Our conclusions is that not all sizes of head can have the flexural mode; the relation between reference frequency of flexural vibration and the thickness of the head is just opposite when two ends is free and the area of bolt is fixed at one end.