Mathematical Simulation of Water Movement through Unsaturated Nonhomogeneous Soils

Source abstract

Abstract The general states of flow of water through unsaturated nonhomogeneous soils have been simulated by the nonlinear diffusion equation. A numerical technique is developed and programed for the IBM 7094 to solve the explicit‐implicit difference scheme analogue of the nonlinear partial differential equation of parabolic‐type. The data utilized in this study for the simulated soil profile are obtained from the experimental work of Nielsen et al. (1964) for vertical drainage and infiltration. Computed cumulative loss and average rate are in reasonable agreement with their field measurements. The results indicate that the average rate of drying and wetting are controlled largely by the physical properties of the soil and their corresponding boundary conditions.