Rogerio N. Costa Pinto
Steven R. Baker
Oscar B. Wilson
Dept. of Phys., U.S. Naval Postgraduate School, Monterey, CA 93943
A three-dimensional finite element model of a high-power, low-frequency ring-shell flextensional transducer [Sparton of Canada, Ltd., model 34A0610] has been developed for use with the ATILA code [Decarpigny et al., J. Acoust. Soc. Am. 78, 1499--1507 (1985)]. A three-dimensional model is needed to represent nonaxisymmetric vibrations that can occur in a dense sonar array. The model was derived from a two-dimensional axisymmetric model developed by Blottman [J. B. Blottman, Naval Undersea Warfare Center, New London Laboratory, Technical Memorandum No. 89-1090 (1989)]. In extending Blottman's model to three dimensions, reasonable simplifications were made to minimize the number of elements required to faithfully represent the dynamical behavior of the transducer in the frequency range of interest. A description of the model and the results of in-air modal and in-water harmonic analyses will be presented. [Work sponsored in part by the Naval Postgraduate School and the Naval Undersea Warfare Center.][sup a)] Lieutenant Commander, Brazilian Navy.