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.

Porous structure parameters have strong influence on the phenomenon of flow and heat transfer in the capillary porous wick of a loop heat pipe.

The volume shrinkage characteristics of porous materials in the drying process are investigated based on the definitions of Volume Shrinkage Coefficient and Shrinkage Isotropicity,with fresh ginger,carrot,potato and banana as the drying materials.

Atthe same time, the influence is discussed of mean pore radius and solid matrix strength of the wetporous material,as well as the temperature and velocity of hot air on the volume shrinkage rate onthe basis of the experimental results.

There is an area of drying rate unvarying with air flow velocity,which is called self-sim-ulation area of Re Number,during porous media drying of microwave and cold air convection.