ASA 124th Meeting New Orleans 1992 October

3aPA7. Finite-amplitude propagation of sound beams, improvements of the Bergen code.

Kjell-Eivind Fr(slashed oh)ysa

Dept. of Math., Univ. of Bergen, Allegt. 55, 5007 Bergen, Norway

An algorithm for numerical solution of the KZK nonlinear, parabolic equation is developed. It is a new and faster version of the Bergen code algorithms starting with Aanonsen et al. [J. Acoust. Soc. Am. 75, 749--768 (1984)]. The computational time on the nonlinear term is reduced, and the possible numerical instabilities when studying pulsed sound propagation are avoided. The algorithm is used for the study of pulsed finite amplitude sound propagation, and comparisons have also been made with experimental results. [Work supported by the Norwegian Research Council for Science and Humanities.]