Study on the Influence of Backing Materials on Acoustic Performance of Hydrophone

摘要

In this paper, a finite element model is established for the acoustic properties of hydrophone sensitivity and lateral mode suppression, and optimization design is carried out. The effects of different backing materials and backing structures on the acoustic characteristics of hydrophones were analyzed and verified by experiments. The result shows that the higher the Young's modulus and the thicker of the backing, the higher the sensitivity of the hydrophone, at the same time, the sensitivity fluctuation in the working frequency range is smaller. When a lightweight material is used as the backing, it is easy to introduce a transverse vibration mode, resulting in sensitivity pits, the transverse mode can be avoided by cutting the piezoelectric material and the backing into smaller units. Through the experiments, we can found that the designed hydrophone has a receiving sensitivity about -200dB in the frequency range of 800Hz-5000Hz, the undulation is less than 3dB and it also has good sound transmission performance.