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arXiv · 2105.03297

Elimination of ringing artifacts by finite-element projection in FFT-based homogenization

Richard J. Leute·Martin Ladecký·Ali Falsafi·Indre Jödicke·Ivana Pultarová·Jan Zeman·Till Junge·Lars Pastewka
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Abstract

Micromechanical homogenization is often carried out with Fourier-accelerated methods that are prone to ringing artifacts. We here generalize the compatibility projection introduced by Vond\v{r}ejc, Zeman & Marek [Comput. Math. Appl. 68, 156 (2014)] beyond the Fourier basis. In particular, we formulate the compatibility projection for linear finite elements while maintaining Fourier-acceleration and the fast convergence properties of the original method. We demonstrate that this eliminates ringing artifacts and yields an efficient computational homogenization scheme that is equivalent to canonical finite-element formulations on fully structured grids.

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Richard J. Leute, Martin Ladecký, Ali Falsafi, Indre Jödicke, Ivana Pultarová, Jan Zeman, Till Junge, Lars Pastewka. 2021-05-07. Elimination of ringing artifacts by finite-element projection in FFT-based homogenization. https://doi.org/10.1016/j.jcp.2021.110931

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