ASA 126th Meeting Denver 1993 October 4-8

2pEA6. Underwater testing of a thermoacoustic sound projector.

Steven C. Black

Naval Res. Lab., Underwater Sound Reference Detachment, P. O. Box 568337, Orlando, FL 32856-8337

For about the last 10 yr, there has been a growing interest in the thermoacoustic method of transduction. Recently, research has been conducted at Los Alamos National Laboratory on the development of a high-power, low-frequency underwater sound projector based on the concept of a thermoacoustic engine [G. W. Swift, J. Acoust. Soc. Am. 84, 1145 (1988)]. The design of this new transducer consists of a long straight tube deployed vertically. The upper portion of the tube is gas filled and contains the heat engine driver. The lower portion is water filled and acts as an impedance matching section. A small-scale demonstration device has been built and was tested both in air and in water. The demonstration device is approximately 9 m in length and operates in the frequency range of 100 to 200 Hz. In conjunction with experimental testing, modeling of the in-water behavior of this demonstration device was also performed. Results from the modeling and the in-water testing will be presented. [Work sponsored by SPAWAR.]