考虑Knudsen扩散影响的水泥基材料湿扩散系数  

Determination of Moisture Diffusion in Cement-Based Materials in the Presence of Knudsen Diffusion

作　　者：陈德鹏[1] 钱春香[2] 

机构地区：[1]安徽工业大学建筑工程学院,安徽马鞍山243002 [2]东南大学材料科学与工程学院,江苏南京211189

出　　处：《建筑材料学报》2009年第6期635-638,共4页Journal of Building Materials

基　　金：教育部新世纪人才支持计划资助项目(NCET-05-0473)

摘　　要：根据水泥基材料的多孔介质特点和内部孔隙尺寸分布特征,结合多孔介质中的湿传输机理,认为水泥基材料的湿传输研究必须考虑Knudsen扩散的影响.根据中、微孔体积的等效直径理论以及气体分子运动论相关原理,推导建立了Knudsen扩散影响系数的理论计算公式,在此基础上,探讨了水泥基材料湿扩散系数的确定方法,并通过实际问题的分析进行了验证.The influence of Knudsen diffusion was proposed in case that Knudsen diffusion is not negligible according to the mechanism of moisture transfer in cement-based materials based on the porous medium characteristic and pore distribution of them. A theoretical formula for calculating the influence of the coefficient of Knudsen diffusion was deduced on the basis of the theoretical equivalent diameter of mesco-micro pore and the kinetic theory of gas. Then the calculation method of moisture diffusion in cement-based materials considering the effect of Knudsen diffusion was discussed with a practical case to show its application.

关 键 词：水泥基材料 湿传输 Knudsen扩散 湿扩散系数 

分 类 号：TU528.01[建筑科学—建筑技术科学]