运用分形方法预测石墨化碳泡沫方向导热系数

Prediction of the Orientation Thermal Conductivity of Carbon Foam using Fractal Model

石墨化碳泡沫是高导热系数材料,具有方向导热性能,垂直发泡方向(xy平面)和沿发泡方向(垂直xy平面)的导热系数有明显的差异。应用分形方法通过确定碳泡沫的泡孔结构的分形维数,结合泡孔热阻单元,分析了石墨化碳泡沫的导热特性,推导出了碳泡沫的方向导热模型。计算结果与文献中石墨化碳泡沫样品的实测值基本一致,该方法为更好地利用其优良的方向导热性能提供了理论基础。

There is a distinct difference in the ability of the high conductivity graphitie carbon foam to conduct heat parallel to the xy-plane compared with heat conduction perpendicular to the xy-plane. With fractal theory, the area fraetal dimension of carbon foam is deduced, and by thermal resistance, a thermal orientation conductivity model of carbon foam is proposed. Through computation, the orientation thermal conductivity of carbon foam is acquired. The value of model forecast is consistent with the actual observed of carbon foam in the literatures. This method has provided the theoretical basis for better using its fine orientation heat conduction performance.