Small low frequency underwater transducers based on discrete periodic structures

A piezoelectric hydroacoustic radiator consisting of a discrete periodic structure with assemblies whose inertial elements are piezoelectrically active and whose elastic elements are passive is considered. Formulas for the resonance frequencies of the radiator and the oscillation amplitudes of its radiating surface are analyzed. Optimal phase shifts between the voltages fed to the piezoelectric elements are found. Experimental results are presented for the case of a three-assembly structure that demonstrates that the above systems may be used as multifrequency radiators.