溢流式嵌镶圆管发射换能器的有限元分析

溢流式嵌镶圆管水声换能器是一种有效的低频宽带发射器，一般存在2种可供利用的谐振方式，即溢流环的液腔谐振和嵌镶圆管的径向谐振。本文首先应用解析的方法获得2种谐振的频率方程，然后应用有限元法建立了一个对称结构的溢流式嵌镶圆管换能器模型，通过ANSYS软件分析换能器的振动情况和响应曲线，并与解析法进行了对比。根据设计制作了溢流环换能器样件，并通过了相应的消声水池试验，试验结果表明，有限元模型计算准确且快捷，显示直观，其谐振频率设计误差可控制在5％以内。最终制作的换能器拥有2．35kHz的液腔谐振频率和6．4kHz的径向谐振频率，最大发射电压响应级为141．97dB，其径向谐振的-6dB带宽为3．9-9．4kHz，可提供全频段的发射带宽（包括液腔谐振在内）为2．1～10kHz±4dB。

Finite Element Analysis of Free-flooded Segmented Ring Transducer

The frequency equations about two resonances of free-flooded segmented ring transducer are obtained via traditional analytic method, and then a circumferential symmetry finite element model of the free-flooded segmented ring transducer is established. The two resonances and the vibrationperformance of the transducer are predicted through ANSYS, and a prototype of the free-flooded ring transducer is designed. The anechoic tank test for the prototype shows that the finite element method（FEM） is suitable for analyzing the cavity resonant performance of the free-flooded ring and the radial resonant performance of the segmented ring transducer, and the design error about resonant frequency can be conti＇olled within 5%. A final transducer prototype based on the above research achieves the cavity resonance of 2.35 kHz, the radial resonance of 6.4 kHz, the maximum transmit voltage response level of 141.97 dB, the radial resonant - 6 dB bandwidth of 3.9 to 9.4 kHz, and the overall available bandwidth （including the cavity resonance） of 2.1 to 10 kHz ＋4 dB.