Calculation of the Directivity Pattern of a Cylindrical Shell Transducer with Syntactic Foam

Underwater sound transducers are often employed under high hydro-pressure. To realize a transducer with the desired directivity in the deep sea, we devise a new transducer construction in which a high-sound-speed material called syntactic foam is attached to a sensitive cylindrical element. To predict the directivity of the transducer, we give a calculation method of the directivity pattern by finite element analysis considering an infinite space. Numerical calculated results agree well with measured directivity patterns, and realization of a transducer with desired directivity is found to be possible.