基于瞬态热线法的橡胶粉导热系数的测量分析

Measurement and Analysis of Thermal Conductivity of Rubber Powder Based on Transient Hot Wire Method

基于瞬态热线法,通过自主设计的松密度-导热系数实验台,能准确测量导热系数与其松密度之间的关系。文中分别测量了松密度大小对普通胶粉、具有相同含量的松焦油、煤焦油的胶粉导热系数的影响。结果表明,粉体的导热系数大小与松密度呈线性关系:随着粉体材料的松密度增加,其导热系数线性增强。比较发现,含煤焦油和松焦油的胶粉的导热系数高于普通胶粉导热系数;相同松密度下,含煤焦油的胶粉导热系数高于含松焦油的胶粉导热系数,普通胶粉导热系数最低。通过分析表明,这种胶粉导热性能的差异与颗粒之间接触面积、空气含量及颗粒表面不同含油层的厚度相关。

A prototype of experimental apparatus was designed for measuring the thermal conductivity of powder materials based on the transient hot wire method in the present work.Several different sample materials,including dry ground tire rubber powder(D-GTR),GTR with pine tar and GTR with coal tar,were adopted for the detecting of the relationship between the bulk density ρ and thermal conductivity λ.It is found that a linear behavior is shown between ρand λ,i.e.increasing ρ can effectively enhance λ.However,different influences of the pine tar and coal tar on the thermal conductivity are found through comparison of the results in which the most significant effect affecting the thermal conductivity of GTR powder is presented for the coal tar.The contact area among particles,content of air and different thickness of tar coating are contributed to these differences in this work.