Comparative research on equivalent circuit and finite element analysis of longitudinal vibration type low-frequency piezoelectric hydrophones

The equivalent circuit theory and ANSYS Finite Element Simulation are used to calculate the performance parameters of longitudinal vibration type composite rod piezoelectric hydrophone, and the two calculation results are compared. It is shown that the resonant frequencies of the receiving sensitivity obtained by the two methods are not in the same place, and there are some differences in the value of receiving sensitivity, and that the bandwidths of receiving sensitivity are all rather wide in the lower frequency band far from the resonance point. It is known that the equivalent circuit theory only considers the one-dimensional longitudinal vibration and idealizes the model. However, the ANSYS finite element analysis considers the longitudinal and transverse modal coupling of the whole model structure, which is closer to the actual model. Therefore, ANSYS has more advantages in the simulated optimization design of hydrophone. The equivalent circuit theory can provide theoretical guidance for finite element simulation because of its obvious physical significance.