Study on Moisture Migration in Humidity Control Building Material with Different Pore Morphologies

Because of the complicated porous structure of humidity control building material (HCBM), random growth method is applied to create isotropic and anisotropic porous microstructures with different porosity, the impact of porosity and pore morphology on water vapor migration in the porous medium are studied. The results show that diffusion properties of water vapor in porous medium largely depend on connectivity of pores, and are related to porosity of porous medium, generally speaking, the bigger the porosity, the better the diffusion properties of water vapor in porous medium; Water vapor diffusion ability along the direction of smaller growth rate of anisotropic structure is worse than water vapor diffusion ability along the direction of bigger growth rate of anisotropic structure. Water vapor diffusion ability of water vapor diffusion direction is perpendicular to the direction of larger growth rate of anisotropic structure is the worst, the comparison between water vapor diffusion ability in isotropic structure and water vapor diffusion ability of water vapor diffusion direction is parallel to the direction of larger growth rate of anisotropic structure should refer the connectivity and porosity of porous medium. The mechanism of water vapor diffusion can be studied intuitively by the method.