为了研究石墨泡沫/共晶盐复合相变材料的等效导热系数，提出了一个立方单元模型。即6块中间开孔的板围成的立方体结构。此模型可通过改变板厚及连通孔直径表征复合材料不同孔隙度下的内部结构。首先根据热阻分析得到石墨泡沫/空气的等效导热系数，与文献中的实验数据进行了对比，验证了立方单元模型的适用性。接着计算得出不同孔隙度下石墨泡沫/共晶盐的等效导热系数。最后分析了连通孔的直径对等效导热系数的影响。发现随着孔隙度的增大，等效导热系数值呈下降趋势。固体石墨骨架对共晶盐的导热系数具有很大的提升作用。随着孔隙度的增加，连通孔直径的变化对整体等效导热系数的影响逐渐变小。
In order to study the effective thermal conductivity (ETC)of the graphite/eutectic salt composite,a cubic unit cell model was proposed in this paper.The cubic structure was comprised of the six plates which has one hole in the center.This model has a good ability to accommodate different structure in the composite through changing the thickness of plate and the diameter of the interconnected pore.Firstly,the ETC of graph-ite/air composite is derived and comparisons of the results between the proposed model and published data in the literature show good agreement.So the validity of the current model is verified.Secondly,the ETC of graphite foam/eutectic salt in the different porosity is calculated.Finally,the effect of the diameter of the inter-connected pore on the overall ETC was analyzed.The results show that with the increase of porosity,the ETC of the composite is on the decline.The solid graphite skeleton has great promotion effect on the thermal conduc-tivity of eutectic salt.The effect of the interconnected pore diameter on the overall thermal conductivity decrea-ses gradually,when the porosity increases.
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