Z-Structured Piezoelectric Transducers: A New Approach for Low-Frequency Small-Size Underwater Projectors

In the ocean engineering applications, the underwater projector with the performance of low frequency, small size, lightweight, and high power is urgently needed. To meet these demands, a z-structured piezoelectric transducer (ZPT) is developed. This new type projector employs the bender beams to achieve a compact zigzag structure. Its coupled longitudinal-bending vibrations are useful to lower the resonance frequency and amplify the output vibrations of ZPT. The finite-element simulations reveal that the bender beams of ZPT affect its performance a lot. Thinning or lengthening the beams will lower its resonance frequency. The tested results of ZPT prototype show a transmitting voltage response (TVR) of 123.9 dB at its resonance frequency of 1.32 kHz. Besides, its size of
$\Phi \,\,120\,\,\times112$
mm and its weight of only ~2.4 kg are attractive. This study indicates that ZPT is capable of being used as a low-frequency small-size underwater projector.