Design og studier av lydkilde for SOBER-prosjektet

Abstract

An ultrasonic sound source was constructed for the University of Bergen’s participation in the Sonic Boom European Research project. A piezoceramic disc was chosen as the active element and some of its properties were examined. The most important material parameters were estimated by means of a Mason type model. The Mason model was further used to compute dimensions and specific impedances of acoustic coupling layers. A quarter-wave and a three-quarter-wave coupling layer were tried in laboratory measurements. Symmetry and other properties of the transducer’s sound beam were inspected at different source levels. Measurements at low amplitudes were compared to the far field of a plane circular piston source. The Bergen Code was employed in solving the KZK equation for a finite amplitude sound beam.