Solutions to range-dependent benchmark problems by the finite-difference method
Stephen, Ralph A.
MetadataShow full item record
KeywordFinite difference method; Range; Benchmarks; Wave equations; Sound levels; Shear waves; Acoustics
An explicit second-order finite-difference scheme has been used to solve the elastic-wave equation in the time domain. Solutions are presented for the perfect wedge, the lossless penetrable wedge, and the plane parallel waveguide that have been proposed as benchmarks by the Acoustical Society of America. Good agreement with reference solutions is obtained if the media is discretized at 20 gridpoints per wavelength. There is a major discrepancy (up to 20 dB) in reference-source level because the reference solutions are normalized to the source strength at 1 m in the model, but the finite-difference solutions are normalized to the source strength at 1 m in a homogeneous medium. The finite-difference method requires computational times between 10 and 20 h on a super minicomputer without an array processor. The method has the advantage of providing phase information and, when run for a pulse source, of providing insight into the evolution of the wave field and energy partitioning. More complex models, including velocity gradients and strong lateral heterogeneities, can be solved with no additional computational effort. The method has also been formulated to include shear wave effects.
Author Posting. © Acoustical Society of America, 1990. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 87 (1990): 1527-1534, doi:10.1121/1.399452.
Showing items related by title, author, creator and subject.
Stephen, Ralph A. (Acoustical Society of America, 1996-10)A numerical scattering chamber based on the time-domain finite-difference solution of the two-way elastic wave equation is applied to a sea surface scattering problem, and excellent agreement is obtained in amplitude and ...
Differences between sound scattering by weakly scattering spheres and finite-length cylinders with applications to sound scattering by zooplankton Stanton, Timothy K.; Wiebe, Peter H.; Chu, Dezhang (Acoustical Society of America, 1998-01)A modeling study was conducted to determine the conditions under which fluidlike zooplankton of the same volume but different shapes (spherical/cylindrical) have similar or dramatically different scattering properties. ...
Hunt, Mary M.; Gove, Lee; Stephen, Ralph A. (Woods Hole Oceanographic Institution, 1983-11)In order to study seismic wave propagation through laterally varying sea floor structures, a software package has been created to generate synthetic seismograms by finite differences. The elastic wave equation can ...