title: A feasibility study of the use of bounded beams resembling the shape of evanescent and inhomogeneous waves.
abstract: Plane waves are solutions of the visco-elastic wave equation. Their wave vector can be real for homogeneous plane waves or complex for inhomogeneous and evanescent plane waves. Although interesting from a theoretical point of view, complex wave vectors normally only emerge naturally when propagation or scattering is studied of sound under the appearance of damping effects. Because of the particular behavior of inhomogeneous and evanescent waves and their estimated efficiency for surface wave generation, bounded beams, experimentally mimicking their infinite counterparts similar to (wide) Gaussian beams imitating infinite harmonic plane waves, are of special interest in this report. The study describes the behavior of bounded inhomogeneous and bounded evanescent waves in terms of amplitude and phase distribution as well as energy flow direction. The outcome is of importance to the applicability of bounded inhomogeneous ultrasonic waves for nondestructive testing.
authors: Georgia Institute of Technology, UMI Georgia Tech-CNRS 2958, George W. Woodruff School of Mechanical Engineering, Georgia Tech Lorraine, Laboratory for Ultrasonic Nondestructive Evaluation "LUNE", 2 Rue Marconi, 57070 Metz, France. nico.declercq@me.gatech.edu
authors: Nico F
authors: NF
authors: Declercq
authors: Oswald
authors: O
authors: Leroy
mesh_terms: D005240:Feasibility Studies; D005583:Fourier Analysis; D016011:Normal Distribution; D014465:Ultrasonics