摘要
从传输机制出发，建立了考虑胀缩效应的含湿多孔介质内部多种输运现象的机理模型，结合解吸等温特性与Ｋｅｌｖｉｎ方程，利用改进的Ｄａｒｃｙ定律推出了液相质传递系数等参数的数学表达式．还将一般分子扩散和Ｋｎｕｄｓｅｎ扩散有机组合，应用改进的Ｆｉｃｋ定律，获得了气相质传递系数等参数的表达式．本模型中各参数物理意义明确，易于确定．
his paper describes a new model for the inner transport phenomena in porous media. It takes into account the volume change process and the concrete transfer mechanism. In this model the desorption isotherm properties and Kelvin's equation are combined, and the modified Darcy's law is used to determine the mass transport coefficients of the liquid-phase moisture and other important parameters in the porous material. Besides, the general molecular diffusion and the Knudsen diffusion are incorporated, and the modified Fick's law is used to determine the mass transfer coefficients of the vapour phase moistureand other parameters. The parameters with clear physical meanings can be determined easily.
出处
《天津大学学报》
EI
CAS
CSCD
1994年第4期436-443,共8页
Journal of Tianjin University(Science and Technology)
关键词
多孔介质
干燥模型
传热
传质
porous material, drying model, desorption isotherm property, heat and masstransfer
