三维编织复合材料宏细观多尺度传热分析

近年来三维编织复合材料在航空、航天等领域得到了广泛应用,而热传导性能是其重要的物理性能之一。根据三维四向编织复合材料细观单胞模型,建立其热传导性能的宏细观多尺度模型,包括等效热传导系数的均匀化模型和温度场分布的多尺度模型;基于宏细观多尺度有限元算法,计算三维四向编织复合材料的等效热传导系数,并与实验结果进行对比;在此基础上,研究编织角和纤维体积含量对热传导系数的影响规律,并确定材料内部的温度场分布。结果表明:等效热传导系数与实验值吻合较好,细观单胞模型能较为真实地反映三维四向编织复合材料的结构构形,宏细观多尺度方法能有效预测三维编织复合材料的热传导性能,并且能有效捕捉材料内部的局部振荡效应。

Multiscale Heat Transfer Analysis of Three-Dimensional Braided Composites

3D braided composites have been widely used in aerospace engineering and thermal conductivity is one of its important physical properties. Based on the mesoscopic unit cell of 3D 4-directional braided composites, the macro- and micro- multi-scale models for predicting thermal properties of 3D braided composites are established, including the homogenization model for the equivalent properties and multi-scale model for the temperature distribution. And the equivalent properties are calculated by the multiscale finite element algorithm, and agree well with the experimental results. The influences of the braiding angle and fiber volume fraction on the thermal conductivity coefficient are also studied. In addition, the distributions of temperature field inside composites are determined, providing a basis for the analysis of the thermo-mechanical coupling