三维机织几何结构的数值表征

推荐一种利用一组数值型参数来定量表征三维机织几何结构的方法。在给定的几何约束和加工约束条件下，由4种纱线系统组成的三雏机织几何结构可用9个结构参数予以数值表征。根据贯穿或分层的角联接结和正交接结的几何特征，分别建立了与之对应的结构参数以及参数间的联系。进一步的研究表明，对于角联接结的三维机织几何结构，9个结构参数中仅有4个是独立的；而对于正交接结的三维机织几何结构，独立的结构参数为5个。一旦确定了独立的结构参数，三维机织几何结构就能被确定；反之，只要织物几何结构已知，则与之相对应的结构参数也就确定了。这里所推荐的数值表征方法可用于三维机织几何结构的设计，如根据三维机织复合材料的性能要求确定各取向纤维的分布等，从而为建立一种具有普适意义的三维机织结构几何模型提供了前提条件，同时也为三雏机织复合材料力学性能的设计提供了统一的设计平台。

Representation of Geometric Architecture of Three-dimensional Woven Structures by Numerical Method

A numerical method is proposed to represent the geometrical pattern of fibrous architecture of 3D woven structures. A set of structural parameters is defined to numerically describe the fibrous architectures under some geometrical and processing constrains. Different geometrical patterns, such as angle interlock and orthogonal interlock with through thickness or layer to layer bindings, are classified. A unit cell of 3D structures is defined with four constituent yam systems represented by nine structural parameters. A mapping relationship between the fibrous architecture and the corresponding structural parameters is thus established. Further study indicates that four out of the nine parameters are necessary to represent 3D woven structure with an angle interlock binding, and that five parameters are retired to describe the structure with an orthogonal interlock binding. Once the structural parameters are determined, the fibrous patterns can be unambiguously identified, and vice versa. In addition to structure presentation, the method can further be applied as a means of structure design, such as determining the numbers of yarns in each yarn system.