纱线在纺织材料中起桥梁作用，两组分交变复合结构纱具有片段化功能效应，对开发智能纺织品具有重要意义。本项目基于申请人团队研发的双通道环锭纺技术，旨在进一步完善该系统纺制两组分交变复合结构纱的成纱原理，实现精确调控纱线结构。本项目拟解决两大问题：一是纤维集合体高精度牵伸。利用显微计算机断层扫描技术获取牵伸区粗纱纤维集合体三维几何模型，进而构建纤维集合体与牵伸系统交互作用的力学模型，借助有限元法模拟不同构型单纤维抽拔过程受力，合理配置摩擦力界分布，以提高牵伸精度；二是气流场作用下前纤维束尾端与后纤维束头端的高速动态精确连接。针对纤维束所处气流集聚区气流场建立几何模型，并将具有较大柔性和长径比的纤维抽象为弹性细杆模型，建立纤维/流场耦合作用有限元动力学模型，实现纤维运动轨迹的数值模拟，采用高速摄像法和数字图像处理技术验证纤维运动轨迹，优化流场状态。

Yarn plays a bridge role in textile materials, and the two-component alternating composite structure yarn has the function of fragmentation, which is of great significance to the development of intelligent textiles. This project is based on the two-channel ring-spinning technology developed by the applicant's team, and aims to further improve the yarn formation principle of the system for spinning two-component alternating composite structure yarns, and realize the precise control of yarn structure. This project intends to solve two major problems: one is high-precision drafting of the fiber assembly. Firstly, the three-dimensional geometric model of the fiber assembly in the draft zone is obtained by using the Micro Computed Tomography (Micro-CT), and then a mechanical model of the interaction between the fiber assembly and the drafting system is constructed. The stress state of the single fiber in extracting process will be simulated with the help of the Finite Element Method, to improve the drafting accuracy with a reasonable distribution of friction boundary; the second is the precise connection of the tail end of the front fiber bundle and the head of the rear fiber bundle under the negative pressure air flow field. Firstly, establish a geometric model for the airflow field in the air gathering area where the fiber bundle is located, and abstract the fiber with greater flexibility and aspect ratio as an elastic thin rod model. Then, establish a finite element dynamic model of the coupling effect between the fiber and the flow field to achieve fiber moving trajectory. The high-speed camera and digital image processing technology will be used to verify the fiber trajectory, and optimize the flow field state.