预制体织造过程的数字单元法模拟研究

Research on Digital Element Method Simulation of Weaving Process of Preforms

预制体作为复合材料的增强相,决定着复合材料的性能。而预制体的性能往往取决于纱线的空间结构,为了反映织物内部纤维束的宏观三维空间结构和微观截面几何构型,通过将纱线离散化,用数值模拟和仿真方法模拟织造过程。本文综述了复合材料预制体织造过程的数字单元法模拟研究进展。在微观几何结构方面,详述了数字单元法研究由理论到应用的发展历程,对先进的数字单元建模方法进行了介绍,指出当前模型对于数字单元法模拟纺织过程较为理想化,未考虑纤维的抗弯刚度、空气阻尼效应以及横向压缩引起的能量损失等工艺参数,指出今后的研究中可进一步优化数字单元法,实现参数化建模,深入研究纤维束变形机理以获得纤维更为真实的微观几何结构模型。

As the reinforcing phase of the composites,the preform determines the performance of the composites.The performance of the precast often depends on the spatial structure of the yarn.To reflect the spatial configuration and micro-geometric structure of the yarn inside the fabric,through the discretization of the yarn,the weaving process is simulated by numerical simulation and simulation methods.We review the progress on digital element method simulation of the weaving process of composite preforms.In terms of micro-geometric structure,this paper details the development process of digital element method research from theory to application and introduces the advanced digital element modeling method.It points out that the current model is idealized for the digital element method to simulate the textile process,and does not consider the bending stiffness of the fiber,the air damping effect and the energy loss caused by lateral compression,etc.This paper also points out that the digital element method can be further optimized in future research and parametric modeling can be realized,and that the deformation mechanism of the fiber bundle is studied to obtain a more realistic micro-geometric structure model.