Bubble Transducer for Radiating High-Power Low-Frequency Sound in Water

Abstract

The bubble transducer consists of a conventional low-impedance electrodynamic driver with an air-filled rubber membrane, or “bubble,” of adjustable volume over the diaphragm. The system at resonance produces large volume displacement of the water with small linear diaphragm displacement at frequencies below 200 cps. For constant diaphragm volume velocity, the addition of the resonating bubble increases the power output by a factor of approximately 1000.