Robust, high-resolution, indexed 3D slowness surfaces for Rayleigh-type waves on Lithium Niobate via parallelised Newtonian flow phase tracking

Grigg, Harriet; Gallacher, Barry J.; Craig, Nathan P.

doi:10.1016/j.jsv.2021.116533

Cited by 1 publication

(1 citation statement)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Other methods have been developed to numerically simulate waves in complex materials, some of which take advantage of matrix formulations [20][21][22][23]. Especially in the case of polycrystalline materials, velocity surfaces [24] or slowness surfaces [25,26] are used to characterize local anisotropy. To take into account inhomogeneity and anisotropy is important in sound wave propagation [27,28] as it gives a clearer view on wave propagation and scattering and also on the emerging sound dispersion in composite or multilayered structures.…”

Section: Introductionmentioning

confidence: 99%

Some Theoretical and Experimental Extensions Based on the Properties of the Intrinsic Transfer Matrix

2022

View full text Add to dashboard Cite

The work approaches new theoretical and experimental studies in the elastic characterization of materials, based on the properties of the intrinsic transfer matrix. The term ‘intrinsic transfer matrix’ was firstly introduced by us in order to characterize the system in standing wave case, when the stationary wave is confined inside the sample. An important property of the intrinsic transfer matrix is that at resonance, and in absence of attenuation, the eigenvalues are real. This property underlies a numerical method which permits to find the phase velocity for the longitudinal wave in a sample. This modal approach is a numerical method which takes into account the eigenvalues, which are analytically estimated for simple elastic systems. Such elastic systems are characterized by a simple distribution of eigenmodes, which may be easily highlighted by experiment. The paper generalizes the intrinsic transfer matrix method by including the attenuation and a study of the influence of inhomogeneity. The condition for real eigenvalues in that case shows that the frequencies of eigenmodes are not affected by attenuation. For the influence of inhomogeneity, we consider a case when the sound speed is varying along the layer’s length in the medium of interest, with an accompanying dispersion. The paper also studies the accuracy of the method in estimating the wave velocity and determines an optimal experimental setup in order to reduce the influence of frequency errors.

show abstract