ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01

3aPAb10. Efficient computation of sound field in horizontally stratified media using a WKB-type approximation with Airy functions.

Y. L. Li

Dept. of Elec. and Comput. Eng., Univ. of Illinois, Rm. 332 North CSRL, 1308 W. Main St., Urbana, Illinois 61801

Conventional fast field programs model a general refractive index profile with a system of horizontal layers. The choice of layer thickness and number of layers depends on frequency, range, and intrinsic properties of the refractive index profile. These constraints result in excessive computation time for many practical cases. To avoid the long run times associated with the layered model, a WKB-type approximation with Airy functions has been applied to the efficient computation of the height-dependent acoustic pressure. Numerical results demonstrate that the new fast field program can reduce the computer time about 50-fold. For higher frequencies, the new fast field program can save more computer time. [Work supported by the US Army CERL.]