毛细多孔物料降速干燥阶段的水分蒸发机理

The Mechanism of the Moisture Evaporation Inside the PorousCapillary Material in the Decreasing Rate Period of Drying

基于毛细管内水分蒸发特性和毛细孔隙分布规律，分析了含湿毛细多孔物料干燥过程中水分蒸发机理，得出以下结论：在典型毛细多孔物料的降速干燥阶段，蒸发过程只在物料内部的某一蒸发区间进行。并建立了描述蒸发区间位置的微分方程，得到了蒸发区间内蒸发强度的计算式，并讨论了毛细多孔体孔隙大小分布对蒸发区间和蒸发强度的影响。

The evaporation region medel,based on the characteristic of the moisture evaploration inside a capillary tube and the pore distribution,is presented for analyzing the moisture evaporation inside the porous capillary material in the decraseing rate period of drying. The differential equation describing the moisture evaporation region is established and the general expression calculating the evaporation intersity is obtained, Then,the influences of the pore distribution on the evaporation region and the evaporation intensity are alse discussed.