Research of the new low frequency, broadband free-flooded piezoelectric underwater acoustic transducer

The transducer which has characteristics of low frequency, broadband, deep submergence is an important direction in research of the underwater acoustic transducer. The resonant frequency of transducer was reduced and the characteristic of deep submergence was enhanced by using the free-flooded structure. A low frequency, broadband transducer with the multicavity free-flooded structure was studied with finite element method in the paper. Then, the finite element modal of transducer was set up with ANSYS software and the structure of the transducer was optimized. A low frequency, broadband transducer with the multicavity free-flooded structure was designed and the excitation of transducer was a free-flooded piezoelectric ring. Finally, the prototype for experiment was produced. Basing on testing, the bandwidth of the transducer was 3kHz-7kHz, which the ripple of the transmitting voltage response does not exceed ±3dB. The transducer achieved target of design.