Scattering of Elastic Waves by Random Heterogeneities

Scattering of Elastic Waves by Inclusions with Thin Interface Layers

Elastic waves are scattered by an elastic inclusion. The interface between the inclusion and the surrounding material is imperfect: the discontinuity in the displacement (traction) vector across the interface is taken to be proportional to the average of the traction (displacement) vectors on the two sides of the interface. Uniqueness theorems are obtained, and boundary integral equations over ...

Scattering of plane elastic waves by three-dimensional diffraction gratings

Scattering of elastic waves in damaged media.

The scattering of elastic waves in a medium with damage from microcracking is discussed. The influence of damage from penny-shaped microcracks within a homogeneous medium is considered. The microcracks are assumed to be randomly oriented and uniformly distributed. Explicit expressions are derived for the attenuation of longitudinal and shear elastic waves in terms of the damage parameter and th...

Stabilization of collapsing scroll waves in systems with random heterogeneities.

In three-dimensional reaction-diffusion systems, excitation waves may form and rotate around a one-dimensional phase singularity called the filament. If the filament forms a closed curve, it will shrink over time and eventually collapse. However, filaments may pin to non-reactive objects present in the medium, reducing their rate of collapse or even allowing them to persist indefinitely. We use...

Elastic Waves Scattering from Corrugated Metal Interfaces

This is a study of elastic waves diffracted by corrugated metallic surfaces. The corrugations consist of triangular grooves with variable parameters. The results of the narrow band experiments show significant diffraction patterns depending on angle and frequency. In addition, a continuous schlieren system is used to visualize the diffracted orders. Measurements were also carried out using a br...