4aUW3. Animations of acoustical pulse (time-domain) signal propagation in a realistic waveguide to high frequencies.

Session: Thursday Morning, May 16

Time: 8:55

Author: Nataly A. Sidorovskaia
Location: Dept. of Phys., Univ. of New Orleans, New Orleans, LA 70148
Author: Michael F. Werby
Location: Naval Res. Lab., Code 7181, Stennis Space Center, MS 39529


Recent developments have made it possible to perform propagation calculations in realistic oceans to high frequencies. It is possible to deal with on the order of hundreds of modes rather quickly and by storing the frequency-domain field over some specified range over the water column and for a fine frequency mesh, it is possible by a new Fourier transform algorithm to reconstruct time-domain solutions in reasonable times. Time frames can be produced for various pulse forms and realistic animations can be created. Thus this enables concentration on the physics of pulse arrivals as well as distortion effects from submerged inclusions. The insight that arises from these calculations, whether they are still shots or actual animations, is very revealing and affords an additional perspective of the complete process that otherwise would not be revealed by less ambitious calculations. A variety of animations and still shots for several physical environments are presented and much of the theoretical results with the intuitive powers that only animations offer are described. [Work supported by Naval Research Laboratory and Office of Naval Research.]

from ASA 131st Meeting, Indianapolis, May 1996