The Study Of Baffled Cylindrical Directional Transducer

Acoustic transducers made from piezoelectric ceramic cylinders usually use the breathing mode of vibration as projectors and hydrophones. The emission of transducers with broadband and directivity has much advantage in signal transmission, such as reducing of signal distortion, increasing of signal noise ratio, decreasing of interference and widening the efficiency. A baffled piezoelectric ceramic cylindrical directional transducer is designed in order to develop a cylindrical transducer with those characters in this target.The research of this paper is focused on the broadband emission of cylinder transducer used multiple resonant mode coupling method and directivity with the rigidity baffle. First of all, the reasons of multimode coupled in different excitation and how to produce directivity are analysed by theory. On this base, the structure and electroacoustical characteristic of the transducer are analysed by the software ANSYS. The rules on bandwidth and directivity of the transducer had been studied by changing the structure effect of both piezoelectric ceramic cylinder and baffle. Finally, a broadband transducer had been designed with bandwidth 15 to 30 kHz, with peak transmitting voltage response 139dB.Finally, the experimental prototype of transducer was processed and its impedance characteristic, transmitting voltage response and directivity were tested. The fluctuation of the experimental prototype of transducer within bandwidth 15 to 30 kHz is less than±4dB and the peak of transmitting voltage response is 137.8dB. The result shows that baffled cylindrical directionaltransducer can be used to produce emission with and broadband, and theexperimental results were approximately coincide with calculated conclusionsgetting by software ANSYS.