摘要
为更好描述含水条件下保温材料导热系数的变化,基于保温材料的高分散相体积特点,在经典Cheng-Vachon模型基础上,通过改变分散相形状,提出了一种适用于任意分散相体积分数的多孔介质导热系数预测模型。通过引入体积修正系数,来间接反映传热路径、界面热阻、分散相形状等因素对导热系数的影响,进而提高模型的预测精度。最后,利用实测数据及已有模型对改进模型的有效性进行验证。结果表明:试验结果验证了模型的可靠性,导热系数与分散相体积成负相关关系,而导热系数与含水率成正相关关系。拓展了Cheng-Vachon模型在保温材料导热系数预测中的应用范围。
In order to better describe the change of thermal conductivity of the wet insulation materials,a thermal conductivity model for the two-phase porous media with any porosity was proposed based on the Cheng-Vachon model.A volume correction parameter was introduced to reflect the influence of pore shape,connectivity,and other factors on the thermal conductivity.With this correction parameter,the prediction accuracy of the proposed model had been improved.To verify the dependability of the proposed model,the measured data and the existed model were used to evaluate the model.The results show that there is a negative correlation between thermal conductivity and porosity,and thermal conductivity is positive correlated with water content.The results have extended the application of the Cheng-Vachon model in the condition of the dispersed phase with high volume fraction.
作者
刘超
王后密
关召帅
李东庆
明锋
LIU Chao;WANG Houmi;GUAN Zhaoshuai;LI Dongqing;MING Feng(CCCC-SHB Fourth Engineering Co.,Ltd.,Luoyang 471013,China;State Key Laboratory of Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《人民黄河》
CAS
北大核心
2023年第12期157-162,共6页
Yellow River
基金
国家自然科学基金资助项目(41701060)。
关键词
渠道工程
保温材料
导热系数
体积修正
channel engineering
insulation material
thermal conductivity
volume correction
