2.5维预制体结构参数的设计方法

由于缺少三维织物的设计理论，使确定2.5维预制体结构参数的确定成为三维纺织复合材料预制体设计人员面临的难题。为此，给出了相似2.5维预制体的定义,按纤维体积含量保持不变推导出相似2.5维预制体结构参数的关系式，以便根据原织物的结构参数计算出新织物的结构参数，特别是可以准确预测新织物的厚度。同时用3个实例验证了该关系式。研究结果表明，所得到的相似2.5维预制体结构参数关系式具有实用价值。

Design method related to 2.5-D preform structural parameters

Being lack of related theory up to now, the designers of 3-D preform are confronted with difficulty when calculating the structural parameters of 2.5-D preform. For this reason, this paper defined the concept of the similar 2.5-D preforms, and worked out the equations of structural parameters’s inner relationships of similar 2.5-D preforms by keeping their fiber volume fractions fixed. By means of the equations, new preform structural parameters could be calculated based on original preform structural parameters, and especially preform thickness could be predicted truly. The equations developed by the paper was verified by three experimental examples. The results show that the 2.5-D preform structural parameters equations possess practicability.