In the present work, we analyze the applicability of two-step homogenization applied to 3D woven composites with high crimp reinforcement. The available micromechanical homogenization approaches (Hashin, Chamis, Hashin-Shtrikman bounds etc.) were developed and validated for unidirectional composites. These formulas have also been used by the community to homogenize tows in 2D and 3D woven composites including reinforcement architectures with high crimp ratios. However, a rigorous study of their applicability to high-crimp geometries is yet to be performed. We utilize Finite Element Analysis (FEA) to calculate the overall engineering constants (Young’s moduli and shear moduli) of tows having various crimp (𝐶𝑅) and wavelength-to-fiber diameter (𝜆/𝑑) ratios. For this analysis, periodic sinusoidal unit cells following shapes of individual fibers are used. Fiber volume fraction is set to 70% and is the same in all cases. Transversely isotropic carbon fiber and isotropic epoxy matrix are used. The results are compared with overall responses of tows modeled using homogenized tow properties obtained from micromechanics and FEA as well as explicitly modeled tows containing multiple parallel fibers. The results of our analysis show dependence of the overall elastic properties on both crimp ratio and the normalized wavelength. Separation of fiber/tow scales is achieved at 𝜆/𝑑 = 50.
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Finite Element Analysis of 3D Woven Composites Using Consumer Graphical Processing Units
The focus of this paper is application of a Graphical Processing Unit (GPU) based solver to linearly elastic finite element analysis (FEA) of composites with threedimensional (3D) woven reinforcements. Aspects specific to this material system including local material orientations, high contrast between elastic properties of constituents, large number of degrees of freedom, and simulation runtimes are discussed. Speedups offered by parallelization via GPUs and regularity of structured grids enable matrix-free implementation of FEA, which requires reassembly of the global stiffness at every iteration of solution of the system of linear equations, but in turn significantly reduces memory requirements. This makes linear analysis of composite structures with explicit reinforcement representation (tens of millions of degrees of freedom) possible on personal computers. Potential applications of this procedure include fast calculation of effective properties for design of novel 3D woven architectures and efficient solution of problems with high degrees of material nonlinearity requiring frequent stiffness matrix updates.
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- Award ID(s):
- 1662098
- NSF-PAR ID:
- 10299919
- Date Published:
- Journal Name:
- Proceedings of the 35th ASC Technical Conference, Hoboken, NJ, USA, 2020
- Page Range / eLocation ID:
- 1181-1189
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.12783/asc35/34923
