棉纤维集合体内部压力传递规律及其变形机理分析

Cotton fiber assemblies will be widely used in the daily life that it can be frequentative squeezed and opened in manufacturing, storage and transportation process.Compressional behavior is an important property of a fibrous mass in relation to its usefulness for bulk purposes.An important problem that has been research by textile scientists and engineers for over sixty years is modeling and texting the compression and recovery behavior of fiber assemblies.The goal of this research is to relate the mechanical properties of individual fibers and how they are arranged in the assembly to the bulk properties of the entire assembly. In this paper, compressive mechanical properties is the main study object in the dynamic mechanical,aims at the problem available in designing assemblies.The internal force distritution will be collected to analyse compressive force of transfer law, as well as deformation of cotton fiber assemblies will be tested for fiber microscopic and assemblies macroscopic deformation parameters.By analyzing the relationship between compressive force and deformation, annotates its properties for compression deformation. Finite element software will be adopted to calculate and analyze the stress and deformation distribution,simulates this process in the force transmission from upper layer to low layer,validate in transfer law of compressive force and deformation.Research results on compressional behavior can provide guidance for designing,processing and applications of cotton textiles.

棉纤维集合体是应用较为广泛的纺织品，其在生产加工、储运过程中被反复多次机械压缩、开松。棉纤维集合体压缩性能的优劣与其各生产环节效率息息相关，也直接影响其各项力学性能。故本项目以棉纤维集合体压缩力学性能为研究对象，采集压缩条件下棉纤维集合体的内压力值，分析棉纤维集合体压缩力传递规律；测量棉纤维集合体压缩条件下纤维微观、集合体宏观的物理参数，分析其与压缩力之间的关系，诠释棉纤维集合体压缩形变特征；利用有限元软件，建立棉纤维集合体压缩传递力学模型，模拟棉纤维集合体压缩力传导过程，进一步验证棉纤维集合体压缩力及形变的传递规律，可为棉纺织品设计、加工、应用环节提供有效技术指导。

棉纤维集合体是应用较为广泛的纺织品。棉纤维集合体压缩性能的优劣与其各生产环节息息相关。本项目以棉纤维集合体压缩力学性能为研究对象，测量棉纤维集合体微观、宏观的物理参数，分析棉纤维集合体压缩力传递规律；诠释棉纤维集合体压缩力传导过程及变形特征。项目研究发现纤维集合体的空隙与其厚度、空隙数量、空隙面积相关，可由纤维集合体空隙率、纤维曲折系数、相邻纤维接触点长度等参数表达。纤维集合体的空隙结构与相对密度、压力建立参数化关系，且纤维的三维取向分布呈二维函数分布。PFC颗粒软件模拟棉纤维集合体，发现纤维集合体内的接触力为网状力链。压缩作用下，纤维间力链网随压力的加载而趋于密集，部分力链增强。薄膜压力传感器采集棉纤维集合体内部压力，发现纤维集合体受压压力分布并非均匀一致，随压缩推进而不断调整压力分布，且其与相对密度密切相关。纤维集合体的轴、侧向压力存在一定关系，且均与相对密度呈指数关系。利用黏弹性理论建立棉纤维集合体的黏弹性本构模型，分析了棉纤维集合体压缩、蠕变、松弛的力学行为，发现模型参数可表征其力学行为，各参数与载荷、加载形式、回潮率等指标相关。测试棉纤维及其集合体摩擦性，发现纤维间以线接触摩擦为主，纤维变形切向角可反应纤维变形程度。纤维集合体的摩擦呈Stribeck曲线规律，相对密度与其摩擦力数值相关。本项目为纤维集合体力学性能研究提供新方法，并填补了纤维集合体压力传递方面的空白。