Electroacoustic modeling of magnetostrictive shells and rings.

The mathematical model of the electroacoustic performance of a force-driven free-flooding magnetostrictive cylinder shell used as an underwater sound transducer, originally presented at the 86th Meeting of the Acoustical Society of America in 1973 [J. Acoust. Soc. Am. 55, 471(A) (1974)] and later developed in NRL Report 7767 (Dec. 1974), has been coded into a computer program called EIGSHIP. This program is designed to predict electrical and mechanical impedances of the loaded shell, transmitting responses, electroacoustic efficiency, surface velocities, farfield beam patterns, and other relevant performance parameters. An experimental check on the predictive capabilities of EIGSHIP was undertaken using three specially constructed magnetostrictive shells which were tested under water load conditions in an indoor test facility. A discussion of the comparison of predicted and measured performance is presented. Also samples of typical computer runs are displayed and commented on. [ABSTRACT FROM AUTHOR]