压实膨润土的导热特性研究

Study on the Thermal Properties of Compacted Bentonite

摘要: 利用Hot disk热常数分析仪测定了压实新疆阿尔泰膨润土在不同条件下的导热性能。探讨了干密度、含水量、孔隙度、饱和度与导热性能的关系，并运用了多种模型对热传导系数进行了预测对比分析。结果表明：阿尔泰膨润土的热传导系数、热扩散系数和体积比热均随着干密度和含水量的增大而增大；相同含水量条件下，均随孔隙度的增大而减小；在饱和度大于20%时，饱和度与热传导系数、热扩散系数和体积比热具有明显的指数关系。通过对比，得到实验所得方程与Kahr模型能较好地预测阿尔泰膨润土的热传导系数。

Abstract: To analyze the relationship between dry density, water content, porosity, saturation and thermal properties, Hot disk thermal constants analyzer is used to measure the thermal properties of compacted Xinjiang Altay bentonite under different conditions. The test results of thermal conductivity are analyzed by several models. The experimental results show that thermal conductivity, thermal diffusivity and volumetric specific heat increase as the dry density and water content increase, and for the same water content, the thermal conductivity, thermal diffusivity and volumetric specific heat decrease as the porosity increase. When the saturation is more than 20%, exponential relationships between saturation and the thermal conductivity, thermal diffusivity, volumetric specific heat are observed respectively. By contrast, the equation obtained by experiments and Kahr’s model is more suitable for predicting the thermal conductivity of Xinjiang Altay bentonite.