Maximizing the accuracy of finite element simulation of elastic wave propagation in polycrystals
Abstract
Three-dimensional finite element (FE) modelling, with representation of materials at grain scale in realistic sample volumes, is capable of accurately describing elastic wave propagation and scattering within polycrystals. A broader and better future use of this FE method requires several important topics to be fully understood, and this work presents studies addressing this aim. The first topic concerns the determination of effective media parameters, namely, scattering induced attenuation and phase velocity, from measured coherent waves. This work evaluates two determination approaches, through-transmission and fitting, and it is found that these approaches are practically equivalent and can thus be used interchangeably. For the second topic of estimating modelling errors and uncertainties, this work performs thorough analytical and numerical studies to estimate those caused by both FE approximations and statistical considerations. It is demonstrated that the errors and uncertainties can be well suppressed by using a proper combination of modelling parameters. For the last topic of incorporating FE model information into theoretical models, this work presents elaborated investigations and shows that to improve agreement between the FE and theoretical models, the symmetry boundary conditions used in FE models need to be considered in the two-point correlation function, which is required by theoretical models.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 01, 2020
- Source ID
- 10.1121/10.0002102
Entities
People
- G. Sha
- M Huang
- M. J. S. Lowe
- Peter Huthwaite
- S. I. Rokhlin
Organizations
- Air Force Research Laboratory
- Beijing Institute of Aeronautical Materials
- China Scholarship Council
- Engineering and Physical Sciences Research Council
- Imperial College London
- Ohio State University