Ultrasonic Wave Propagation in Non Homogeneous Media

Non Destructive Testing and Non Destructive Evaluation using Ultrasounds covers an important field of applications and requires a wide range of fundamental theoretical, numerical and experimental investigations. In the present volume, the reader will find some relevant research results on wave propagation in complex materials and structures which are concerned with today's problems on composites, bonding, guided waves, contact or damage, imaging and structural noise. The fifth meeting of the Anglo-French Research Group on "Wave propagation in non homogeneous media with a view to Non Destructive Testing", where all these results were presented, was held in Anglet, France, June 2-6, 2008.

Contenu

The WKB method applied to the reflectiontransmission by a depth-varying random distribution of cylinders in a fluid slab-like region.- Advances in ultrasonic testing of austenitic stainless steel welds. Towards a 3D description of the material including attenuation and optimisation by inversion.- Imaging of defects within austenitic steel welds using an ultrasonic array.- Materials and mechanical aspects of bonded joints.- The causal differential scattering approach to calculating the effective properties of random composite materials with a particle size distribution.- Modelling of scattering of ultrasounds by flaws for NDT.- Finite element computation of leaky modes in stratified waveguides.- Ultrasonic bulk wave propagation in concentrated heterogeneous slurries..- Dynamics of elastic bodies connected by a thin adhesive layer.- Acoustic wave attenuation in a rough-walled waveguide filled with a dissipative fluid.- Some advances towards a better understanding of wave propagation in civil engineering multiwires trands.- A numerical method for the simulation of NDT experiments in an elastic waveguide.- Finite elements for a beam system with nonlinear contact under periodic excitation.- Nonlinear acoustic fast and slow dynamics of damaged composite materials: correlation with acoustic emission.- Asymptotic expansions of vibrations with small unilateral contact.- Propagation of compressional elastic waves through a 1-D medium with contact nonlinearities.- 3D Finite Element simulations of an air-coupled ultrasonic NDT system.- The reverse time migration technique coupled with finite element methods.- Modelling of corner echo ultrasonic inspection with bulk and creeping waves.- Attenuation of Lamb waves in the vicinity of a forbidden band in a phononic crystal.- 3D orthogonality relations for the surface waves and the far field evaluation in viscoelastic layered solids with or without fluid loading.- Damage detection in foam core sandwich structures using guided waves.- Sensitivity of the guided waves to the adhesion of lap joints: Finite Element modeling and experimental investigations.- Guided waves in empty and filled pipes with optimized magnetostrictive transduction.- Piezoelectric material characterization by acoustic methods.- Ultrasound characterization of aggregated red blood cells: towards in vivo application.- A 3D semi-analytical model to predict the behavior of ultrasonic bounded beam traveling in cylindrical solid bar embedded in a solid matrix..- Comparison between a multiple scattering method and direct numerical simulations for elastic wave propagation in concrete.- Investigation of a novel polymer foam material for air coupled ultrasonic transducer applications.- Dual signal processing approach for Lamb wave analysis.- Structural health monitoring of bonded composite patches using Lamb waves.- Simulation of structural noise and attenuation occurring in ultrasonic NDT of polycrystalline materials.- Ultrasonic array reconstruction methods for the localization and the characterization of defects in complex NDT configurations.- Investigation of damage mechanisms of composite materials: Multivariable analysis based on temporal and wavelet features extracted from acoustic emission signals.- Investigation of damage mechanisms of composite materials: Multivariable analysis based on temporal and wavelet features extracted from acoustic emission signals.- Propagation of elastic waves in a fluid-loaded anisotropic functionally graded waveguide: Application to ultrasound characterization of cortical bone.- Coherent wave propagationin solids containing spatially varying distributions of finite-size cracks.