中文摘要：

目前孔道网络干燥理论中普遍以“人造多孔介质”为孔道网络模拟的研究目标，尚未涉及实际多孔体的应用问题。以农副产品中常见孔隙直径范围（10^-7～10^-4m）的自然多孔介质为研究对象，运用分形几何学、多孔介质渗流物理和传递过程原理。建立了描述多孔介质干燥过程热质传递的分形孔道网络模型和规则孔道网络模型。模型中考虑了多孔介质孔隙内的液相流动、汽相扩散、温度梯度以及孔道微细结构特征等诸多因素对干燥过程热质传递特性的影响。为了更准确地契合自然多孔介质的孔道网络拓扑结构，应用分形孔道网络替代了通常采用的规则孔道网络。

英文摘要：

A fractal pore network model for unsteady drying process of a natural porous body is developed based on the theories of fractal geometry, drainage and percolation through porous media and transport- process. Various phenomena, such as liquid-phase flow, vapor-phase diffusion, temperature gradient, as well as pore microstructure characteristic were considered into the mathematical model. To get a better accordance with a real pore network topological structure, a fractal pore network, instead of a regular pore network, was established.