空隙率与含水率对SiC颗粒有效热导率的影响

The influence of voidage and moisture content on the effective thermal conductivity coefficient of SiC particles

为研究Si C颗粒材料的导热性能,设计了一热探针法测热导率实验装置,对不同空隙率与含水率的Si C颗粒材料有效热导率进行了测量。实验结果表明:含水率一定时,有效热导率随空隙率的增大而减小,开始下降较快,当空隙率大于0.48以后逐渐变缓。空隙率一定时,有效热导率随含水率的增大而增大,开始增加较快,但当含水率超过15%后,含水率对整个有效热导率的影响程度变小。根据测量数据,拟合得到Si C颗粒材料有效热导率关于空隙率和含水率的预测公式。

A measuring device based on thermal probe method was set up to measure the thermal conductivities of SiC particle materials with different void- ages and moisture contents. The experimental results showed that the effective thermal conductivity decreased with the voidage increasing for a certain moisture content. It decreased fast at first, and then gradually slowly when the voidage was greater than 0.48. The effective thermal conductivity increased with the moisture content increasing for a certain voidage. It increased quickly at first, but the moisture content had less influence on the effective thermal conductivity when it was greater than 15%. According to the experimental data, a prediction formula was obtained for explaining the relationship between the effective thermal conductivity and the voidage, the moisture content for SiC particle materials.