Accession Number:

ADA222625

Title:

Acoustic Scattering by Near-Surface Inhomogeneities in Porous Media

Descriptive Note:

Final rept. May 1986-May 1989

Corporate Author:

OPEN UNIV MILTON KEYNES (UNITED KINGDOM) FACULTY OF TECHNOLOGY

Report Date:

1990-02-21

Pagination or Media Count:

252.0

Abstract:

A theoretical and experimental investigation into the influence of near-surface buried inhomogeneities on the reflection of air-borne acoustic fields at a porous ground surface has been conducted based on the assumption that the ground supports only one wave type. Two theoretical treatments of this problem are presented, both involving reformulations of initial boundary value problems as boundary integral equations. Predictions of these formulations are compared with each other and with experimental data. The theoretical models enable constraints and possibilities to be discussed in the context of use of level difference spectra for acoustic detection of surface and sub-surface inhomogeneities. A final appendix is concerned with a theoretical study of surface waves on proelastic surfaces. Keywords Acoustic scattering Boundary elements Surface waves Reflection Transmission.

Subject Categories:

  • Acoustic Countermeasures
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE