复合材料有效热导率的解析表达式一直是传热问题中人们想要解决的问题。本文选用合适的单元体,采用热阻模型和积分平均方法,分别对分散相为球体和圆柱体的两相复合材料的有效热导率进行了推导。对于多孔复合材料,当孔隙率较大或温度较高时辐射换热的影响不能忽略,本文分析了气孔为球体或圆柱体时辐射换热对其有效热导率的影响。将计算所得有效热导率与相关实验数据进行了比较,结果表明两者吻合较好,证明了公式的准确性。
A long-standing thermal transport problem is the analytical determination of the effective thermal conductivity in composite materials. Based on the thermal resistance model and integration method, two theoretical expressions for the effective thermal conductivity in two-phase composite materials in which the dispersed phase consists of spheres or cylinders in cubic arrangements were derived. For porous composite materials, the effect of radiation could not be neglected when the temperature or porosity of the composite materials were high, this effect was analysed when the porous are spheres or cylinders. The calculation values agreed well with the experimental results obtained from the other literatures which showed the method is effective.