High-Fidelity Fibrous Shell for Fiber-Reinforced Composites Preforming

Simulating the preforming of fiber-reinforced composites is essential for manufacturing optimization. However, classical shell elements often yield inaccurate results due to the materials' unique deformation mechanisms, such as fiber quasi-inextensibility and slippage. A high-fidelity fibrous shell element was developed to address these issues. The model incorporates a modified virtual work principle and kinematics to accurately simulate material normal rotation. In-plane bending was introduced to eliminate numerical instabilities and improve prediction accuracy. For multi-orientation laminates, a homogenized multilayer strategy was proposed, grouping plies by orientation and using a master-slave contact algorithm. This strategy maintained high accuracy while improving computational efficiency by an order of magnitude. Validation experiments confirmed the model's accuracy in predicting deformation, shear angles, and inter-ply slippage, providing an effective solution for industrial-scale composite preforming simulation.