Cavity-Loaded Piston Resonators

Abstract

A piston-type resonant element for use in underwater sound-transducer arrays is described. The acoustic loading on the piston is varied by the use of a shallow cavity. The element is stable under high hydrostatic pressure, and its efficiency is higher than 90% over a broad bandwidth. An equivalent circuit that successfully reproduces the measured characteristics of the transducer is developed.

ELECTROACOUSTIC TRANSDUCERS FOR A 10,000-psig UNDERWATER SOUND TRANSDUCER CALIBRATION FACILITY FOR THE FREQUENCY RANGE 10 TO 4000 Hz

“…The noninal capacitance of each disk is 3200 pF, making the total capacitance about 0.225 jF . The transducer is filled completely with Dow Corning 220 silicone fluid, thus eliminating the need for a seal around the magnesium plate with its attendant zhear losses [8]. The stability under hydrostatic stress with this consLruction is much better than that of designs in which the piezoelcctric material is subject to one-or two-dimensional stress [9,10].…”