Accession Number : AD0739722

Title :   Impedance of Interstitial Gaps in Transducer Arrays.

Descriptive Note : Technical memo.,

Corporate Author : PARKE MATHEMATICAL LABS INC CARLISLE MASS

Personal Author(s) : Sherman,Charles H.

Report Date : NOV 1970

Pagination or Media Count : 9

Abstract : The interstitial gaps between transducers in an array present an extremely difficult feature of the overall problem of acoustic radiation from Sonar arrays. Accurate solutions in practical cases can probably be obtained only by numerical finite element methods, although Mangulis has obtained some useful results for infinite planar arrays by a more analytical approach. It is usually possible to divide the region between transducers in an array into separate interstitial gaps such that behind each gap there is a certain volume filled with water and bounded by transducer housings and other parts of the structure. In the finite element approach the entire interstitial volume can be included in the analysis. In Mangulis' approach the interstitial surface facing the pen medium is divided into imaginary rigid elements with some specified internal impedance accounting for the remainder of the interstitial volume. He then makes use of the special properties of the infinite planar array to solve the problem. Any array can be approached in the same fashion. The basic informlation required before this approach can be applied, or before Mangulis' results can be used, is the interstitial impedance. The objective of this memorandum is to discuss some methods of estimating this impedance. (Author)

Descriptors :   (*SONAR ARRAYS, ACOUSTIC IMPEDANCE), TRANSDUCERS, MATHEMATICAL MODELS

Subject Categories : Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE