High-Power Terfenol-D Flextensional Transducer

摘要

A flextensional underwater acoustic projector, powered by Terfenol-D and operatedat a depth of 400 ft (122 m), has been driven to a source level of 212 dB//uPa-m at the Naval Undersea Warfare Centers (NUWC) Seneca Lake Test Facility. The flextensional shell was a modified Class IV shape having concave, rather than convex, radiating surfaces. The geometry of the shell was similar to one described by Merchant U. S. Patent No. 3,258,738, June 28,1966. The shell cross-section was circumscribed by a rectangular area 9.8 x 5.0 inches (250 mmx 126 mm), and the height between the end flanges was 5.8 inches (148 mm). At the resonance frequency of 930 Hz, the projector was omnidirectional, and so the radiated acoustic power was 14 kW. The ac efficiency was 52 percent, and the overall (ac + dc) efficiency was 45 percent. The mass of the transducer was 34 Ibm (15.4kg). With a mechanical quality factor, Q sub m, of 4.7, the projector