纤维增强复合材料宏细观传热分析

利用有限元单胞方法,通过对复合材料结构进行多尺度建模,分析了复合材料的传热性能,讨论了不同因素对于复合材料热传导性能的影响。首先采用有限元单胞法获得单层板的热物理性能,再根据具体铺层次序获得多层板的热物理性能,最后针对一种实际使用的航天复合材料支架结构进行了防热和承载能力的计算和试验。结果表明,复合材料单层板的热传导性能呈各向异性,沿纤维方向的热导系数与纤维体积比呈线性关系,垂直纤维方向的热导系数与体积比呈非线性关系,计算结果与试验结果吻合较好,文中采用的方法可用于复合材料结构的导热计算。

Micro-macro scale heat transfer analysis of fiber reinforced composites

By use of the finite element cell method, the thermal conductivity of composites is analyzed through Multi-Scale modeling for composites structure. The effect of different factors on composites thermal conductivity are discussed. Firstly, the thermal properties of laminate are obtained by finite element cell method. Followed, the thermal properties of Lamia are obtained according Laminate layer order. Finally, thermal protect and carrying capacities analysis are proceeded aimed at a certain composites bracket structure actually used in space vehicle. The results indicate that the thermal conductivity of Laminate shows anisotropy. The conductivity along fiber direction is in direct proportion to the volume fraction of fiber, while the conductivity vertical to the fiber direction is nonlinear relative with the volume fraction of fiber. The calculation results agree well with experiment results. The method used in this paper is capable for composites heat transfer calculation.