ASA 126th Meeting Denver 1993 October 4-8

5aPA14. Sound propagation in inhomogeneous media above a ground with a barrier.

Y. L. Li Michael J. White

U.S. Army Construction Eng. Res. Lab., P. O. Box 9005, Champaign, IL 61826-9005

To study the problem of scattering of acoustic waves from a ground with a barrier, the exact expression of the Green's function due to a line source embedded in a layered medium has been successfully incorporated into the Helmholtz--Kirchhoff integral equation. An extension of the method of moments, which can solve the Helmholtz--Kirchhoff integral equation for studying the problem of sound scattering in the inhomogeneous medium has been developed. Using the method, the effects of scattering in the region beyond a barrier are studied for situations when the background medium is inhomogeneous. The effects of the inhomogeneous atmosphere are discussed. Several interesting examples will be presented.