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arXiv · 1701.09131

On the choice of homogenization method to achieve effective mechanical properties of composites reinforced by ellipsoidal and spherical particles

Viwanou Hounkpati·Vladimir Salnikov·Alexandre Vivet·Philippe Karamian-Surville
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Abstract

In this paper, several rigorous numerical simulations were conducted to examine the relevance of mean-field micromechanical models compared to the Fast Fourier Transform full-field computation by considering spherical or ellipsoidal inclusions. To be more general, the numerical study was extended to a mixture of different kind of microstructures consisting of spheroidal shapes within the same RVE. Although the Fast Fourier Transform full field calculation is sensitive to high contrasts, calculation time, for a combination of complex microstructures, remains reasonable compared with those obtained with mean-field micromechanical models. Moreover, for low volume fractions of inclusions, the results of the mean-field approximations and those of the Fast Fourier Transform-based (FFTb) full-field computation are very close, whatever the inclusions morphology is. For RVEs consisting of ellipsoidal or a mixture of ellipsoidal and spherical inclusions, when the inclusions volume fraction becomes higher, one observes that Lielens' model and the FFTb full-field computation give similar estimates. The accuracy of the computational methods depends on the shape of the inclusions' and their volume fraction.

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Viwanou Hounkpati, Vladimir Salnikov, Alexandre Vivet, Philippe Karamian-Surville. 2017-01-31. On the choice of homogenization method to achieve effective mechanical properties of composites reinforced by ellipsoidal and spherical particles. https://arxiv.org/abs/1701.09131

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