单向纤维复合材料导热性预测

本文利用均匀化方法预测复合材料导热性。采用这一方法给出了单向纤维复合材料沿纤维方向的导热性表达式;将该方法与有限元技术结合得到了在垂直于纤维方向上复合材料导热性数值形式的预测结果。根据这些结果我们用曲线形式给出了材料导热性同各组分体分比间的关系,分析了体分比、纤维截面形状和分布方式、纤维和基体间的相对导热系数等因素对材料整体导热性影响。注意到纤维分布的随机性,本文还研究了纤维相对位置对材料导热性的影响,指出相对位置的变化可导致材料的各向异性导热性。本文指出基体相导热性对材料整体导热性的影响比纤维相的影响更重要。和已有的理论和实验结果的比较说明,本文提出的方法是很有效的。

PREDICTION OF THERMAL CONDUCTIVITY OF UNIDIRECTIONAL FIBER REINFORCED COMPOSITES

The homogenization method is used to predict the thermal conductivity. of unidirectional fiber reinforced composites. A prediction expression of the thermal conductivity in the direction along the fiber is given by means of this method. Based on the method, using finite element technique,the data results of the thermal conductivity in the direction normal to the fiber are obtained. On the basis of the results obtained,the dependence of the thermal conductivity of composites on the fiber volume fraction is given in curves. The effects of the volume fraction, cross section shape of fibers and their distributing array in the matrix, and the relative conductivity of the fiber and matrix, on the thermal conductivity of composites are analyzed. Observing the random distribution of the fiber in the matrix, the effect of the relative position between fibers on the thermal conductivity of composites is also studied , and it is pointed out that the change of this position may induce anisotropy of composites. It is found that the influence of the matrix property on the conductivity of composites is more important than that of the fiber's property, Comparison with the results of other theoreticl methods and experiments implies that the method proposed is effective.