| The flextensional transducers are typically used as low frequency, high power projectors. Because the class VII flextensional transducers have small QM factor and are adapt to deep water application, we will do detailed research to them in this article.Because the structures of class VII flextensional transducers are very complex, we will do the research using finite element analyse software ANSYS in this article. Firstly, in order to analyse the relationship between the structure parameter and the performance of the transducer, some analyses has been done to the model of the transducer. The analyses referred above include the modal analysis and harmonic analysis, and the performance parameters include the resonance frequency in the air and water, the conductance in the air, the transmitting voltage response in the water and the QM factor. Secondly, in order to analyse the effect of each structure parameter to the stress intensity of the transducer, static stress analysis have been done to the model by simulating the outside force. Lastly, the optimum dimension have been got basing on the relationship referred above. The resonance frequency of the model in the water is 1850Hz, and the transmitting voltage response is 133dB, and the quantity of QM factor is 3.8.Finally, according to the dimension of the model, practical transducer has been made and measured. The resonance frequency of the transducer is 1.5kHz, the transmitting voltage response is 125dB, and the quantity of QM factor is 2.7. The result shows that the class VII felxtensional transducer have the advantage of low frequency , relatively lower QM factor, and small size, and it is omni-directional working at the fundamental flexural mode. ANSYS software is very useful in the class VII flextensional transducer design. |
