Structural Design to Maximum Radiating Power of Langevin Bolted Ultrasonic Transducer

Abstract

Langevin bolted transducers (BLT) with two piezoelectric ceramics inserted between the front and rear plates are widely used in ultrasonic cleaner transducers and components of underwater acoustic antennas for a fish finder [1, 2]. And it is very important to attain a maximum ratio of vibrating velocities of the front and rear plates of transducers in radiating medium by choosing the optimal dimension of the front and rear plates of ultrasonic transducers. Prior studies introduced the vibrating mode analysis of BLT using FEM analysis and ultrasonic applications [3, 4, 5]. But study about the detailed structural design of transducers with the maximum vibrating velocity ratio of the front and back plates in the radiating medium based on the electromechanical equivalent circuit analysis is hardly found. In this paper we identified the optimal geometrical dimension of the front and rear plates of transducers with maximum vibrating velocity ratio for 20kHz of working frequency and applied FEM analysis using the ANSYS software. These are based on the analysis of 1-D longitudinal vibrating equivalent circuit for BLT inserted two piezoceramics between the front and rear plates. The front plate is conical shaped and rear plate is cylindrical shaped and these are consisted of different materials.