2aUW7. Modeling the effects of shear conversion on low grazing angle bottom penetration.

Session: Tuesday Morning, May 14

Time: 10:20

Author: Stanley A. Chin-Bing
Location: Naval Res. Lab., Stennis Space Center, MS 39529-5004
Author: Joseph E. Murphy
Location: Univ. of New Orleans, New Orleans, LA 70148


Modeling shear conversion with finite-element/finite-difference codes at a kilohertz and above is difficult due to the number of computational elements needed for such small wavelengths. Typically six to ten nodes per wavelength are required to attain good accuracy. Thus, a typical shallow-water two-dimensional scenario can require hundreds of thousands of computational elements. In this model study, a brute-force hybrid approach is applied. The computational resources of supercomputers with large memories are combined with hybrid modeling techniques to produce simulations of compressional/shear-wave conversions at low grazing angles over range-dependent bathymetry. Examples will be presented that illustrate the effects of these conversions in both horizontally stratified and inhomogeneous anelastic ocean bottoms. [Work supported by ONR/NRL and by High Performance Computing grants.]

from ASA 131st Meeting, Indianapolis, May 1996