Numerical Simulations Of Soil-Water Movement In Drip Irrigation Under A Ponding Condition

Proper management of irrigation can increase water-use efficiency and agricultural productivity. Microirrigation, such as drip irrigation, offers the opportunity for precise applications of water. The design and management of drip irrigation systems requires understanding of water distribution and dynamics within the wetted soil volume. The information may be obtained by means of experiments and numerical simulations.In this study, a lab experiment was carried out to determine the relationship between trickle discharge rates and the corresponding ponding areas for different soils. The relationship was used to modify the top boundary condition of a numerical model, which was applied to simulate three-dimensional axisymmetric infiltration processes. The modified model properly quantified the effect of surface ponding areas related to trickle discharge rates and soil hydraulic properties on the infiltration processes. Simulated results showed that the ponding area resulted in water moving more quickly in the horizontal direction than in the vertical direction. The simulated results were well comparable to the experimental data. The study provides the necessary information for improving drip irrigation design and management.