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。 Based on the evaporation characteristics of capillary water and the distribution of capillary porosity, the mechanism of moisture evaporation in the process of drying porous material with wet capillary was analyzed. The conclusion is drawn as follows: During the desiccation drying phase of typical capillary porous material, An evaporation interval. The differential equation describing the evaporation interval was established. The calculation formula of the evaporation intensity in the evaporation interval was obtained. The influence of pore size distribution on evaporation interval and evaporation intensity was also discussed.