Reflection and refraction of a harmonic SH wave at the interface of two dissimilar media with microheterogeneity

Reflection and refraction of harmonic SH-waves from the interface of two dissimilar media with microheterogeneity is studied. The effect of the microheterogeneity on the overall behavior of the media is taken into account by adding higher order displacement gradients in the stress-strain relationship. It is found that a harmonic wave reflects back with the same angle of the incident wave, like in a classical case. However, it is found that the direction of propagation of the refracted wave is dependent on the wave number. It is also shown that the critical angle for which the incident wave cannot be transmitted to the other half plane is dependent on the wave number. © 2012 American Society of Mechanical Engineers

A Novel approach for modeling mechanical behavior of porous media

Nanotechnology 2011: Advanced Materials, CNTs, Particles, Films and Composites - 2011 NSTI Nanotechnology Conference and Expo, NSTI-Nanotech 2011A multi-scale novel homogenization technique is introduced to model mechanical behavior of open-cell porous media. The proposed method consists of primarily four components. The first component is based on two assumptions. First, a random porous structure can be approximated by superimposing regular grids that are interacting with each other at "junction" points. The second component consists of replacing each grid by an equivalent continuum. The forces at the junction points are also replaced by interacting body forces. The third component is to represent the equivalent media by single medium by expressing the "average stresses" in the elastic mixture in terms of the "average displacement" It is discussed how to extract the information about the geometrical and mechanical properties of the grids by comparing the analytical and experimental data for the dispersion of waves propagating in porous medium.Clean Technology and Sustainable Industries Organization (CTSI);European Patent Office;Greenberg Traurig;Innovation and Materials Science Institute;Jackson Walker L.L.P