Composite forming simulation for non-crimp fabrics based on generalized continuum approaches

连续纤维增强复合材料（CFRP）具有重量轻、性能高等优点。在可能的增强材料中，NCF（无卷曲织物）提供了一个有趣的解决方案，并越来越多地用于高负荷结构。这些纤维是直的，通过可调整的针脚粘合在一起。然而，这些nfc的形成是微妙的。所涉及的变形机制是特定的，没有可靠的方法来模拟成形过程。用于成形仿真的经典柯西力学模型不能同时表达纤维的几乎不可伸缩性、纤维与线之间的滑移以及纤维的弯曲刚度。这个项目的目标是开发使用广义连续介质模型考虑这些不同点的模拟方法。为了模拟纱线之间可能存在间隙的情况，将构建介观模型。将在纱线和钢筋水平上进行机械测试，以确定在模拟中实施的模型，特别是广义连续环境模型。复杂形状预成形件的实验成形试验将验证悬垂模拟的有效性。

Continuous fiber reinforced composites (CFRP) are used to provide light weight and high performance. Among the possible reinforcements, NCF (Non Crimp Fabric) provides an interesting solution and are increasingly used for highly loaded structures. The fibres are straight and bonded together by stitches that can be adapted. Nevertheless, the forming of these NCFs is delicate. The deformation mechanisms involved are specific and there are few reliable approaches to simulating the forming process. The classical Cauchy mechanical models used for forming simulation are not able to simultaneously express the almost inextensibility of the fibres, the slippage between the fibres and the stitches and the bending stiffness of the fibres. The objective of this project is to develop simulation approaches that takes these different points into account using generalized continuous media models. To model the cases where gapping between the yarns will be possible, mesoscopic models will be constructed. Mechanical tests, at the yarn and reinforcement level, will be carried out to identify the models implemented in the simulations and in particular the generalized continuous environment models. Experimental forming tests on preforms of complex shapes will validate the draping simulations.