CE 5310 Lecture Notes - Lecture 7: Max Born, Standing Wave, Mie Scattering
Document Summary
Dispersion phenomenon is that the shape of the wave packet changes as it propagates in space. The slight difference in the phase velocities of individual wave components causes such phenomenon. In linear elastic, homogeneous and isotropic materials, the dispersion can occur when propagating waves are guided within boundaries. A dispersive wave packet that includes several wave components with different phase velocities will travel with group velocity. Also, the energy of the wave packet is transferred by this velocity, so the group velocity and the energy velocity of a wave packet should be identical. Scattering is a complex elastic wave reflection phenomenon, occurring when propagating elastic waves encounter discontinuities (hereafter, scatterers) such as cavities and defects (graff, 1991). Thus, the wave scattering is boundary value problem. Figure 1 shows the schematic representation of wave scattering and the total wavefield including incident and scattered waves. If the geometry of a discontinuity is complicated, it is difficult to solve the wave scattering problem.
