Modeling of Quasi-Parallel Fiber Networks at the Microscopic Scale

The understanding of the mechanical behavior of quasi-parallel fibers network is an important issue for the development of the manufacturing processes of fibers reinforced composite materials. This study presents a numerical model of quasi-parallel fiber networks, which consists of a realistic representation of the fiber network geometry, and a reliable simulation strategy to reproduce the main phenomena at the fiber scale. To obtain feedback on this approach, experimental compaction was performed on a bundle of polyester fibers. The experiment was combined with X-ray tomography scans of the specimen to extract the initial state and use it to create a CAD model, implemented in finite element simulations. Each fiber is modeled by 3D linear beam elements, and the contact law between the fibers is based on the Hertz contact model taking fiber friction into account. The comparison between numerical and experimental show good coherence, demonstrating the potential of the strategy.