SIMULATION OF DRYING PROCESS OF A MOIST POROUS SOIL

Global climate changes caused by global warming have critical consequences on the quality of arable land. A drying process of a moist porous sample of arable soil is studying in this contribution on the bases of the model of air and moisture transfer. The transfer considers from the porous sample to the external environment. In addition, the model also takes to the account the phase transition of water to saturated water vapor in the pores of the sample. Using the variables separation method, we determine an exact model solution that includes the concentration of dry air, the concentration of water, the concentration of water vapor and the evaporation rate function. The model consists of four equations. Three of them describe diffusion processes for air, water, and water vapor in the soil sample including phase transition. The fourth equation is algebraic one and describes three complementary parts of the soil pores volume space, the parts, where air, water, and water vapor are present. The dynamics of the solution changes in the sample is also determined. The dynamics give us a notion about the entire sample drying process. The presented methodology may be partially used to determine the quality of arable land in the global soil market.