Finite element and semi-analytical study of elastic wave propagation in strongly scattering polycrystals

Autor: Huang, Ming, Huthwaite, Peter, Rokhlin, Stanislav I., Lowe, Michael J. S.
Rok vydání: 2021
Předmět:
Zdroj: Proceedings of the Royal Society A 478(2022): 20210850
Druh dokumentu: Working Paper
DOI: 10.1098/rspa.2021.0850
Popis: This work studies scattering-induced elastic wave attenuation and phase velocity variation in 3D untextured cubic polycrystals with statistically equiaxed grains using the theoretical second-order approximation (SOA) and Born approximation models and the grain-scale finite element (FE) model, pushing the boundary towards strongly scattering materials. The results for materials with Zener anisotropy indices A>1 show a good agreement between the theoretical and FE models in the transition and stochastic regions. In the Rayleigh regime, the agreement is reasonable for common structural materials with 11, a semi-analytical model is proposed by iterating the far-field Born approximation and optimising the iterative coefficient. The proposed model agrees remarkably well with the FE model across all studied materials with greatly differing microstructures; the model validity also extends to the quasi-static velocity limit. For polycrystals with A<1, it is found that the agreement between the SOA and FE results is excellent for all studied materials and the correction of the model is not needed.
Comment: 26 pages, 9 figures, 3 tables, submitted to Proceedings of the Royal Society A
Databáze: arXiv