The experimental and numerical results on the processes of capillary impregnation and drying of porous materials are presented. Two methods of humidification of the media with high developed surface and inner porous structures are considered. Comparison of the methods is performed, and the influence of the impregnation velocity on the silica gel grain geometries is analyzed. The drying of the silica gel is carried out in three modes: microwave, convective and acoustic convective modes. The effect of the mode on the drying velocity and quality of the drying material is demonstrated. A mathematical model based on 2D diffusion law is proposed for description of the experimental data. Numerical distributions of moisture in cylindrical silica gel samples are obtained for different initial moisture values. In this case, empirical diffusion coefficients along with water-yielding capacity dependence on the acoustic-convective frequency are implemented.
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