Numerical Modeling And Experiment On Soil Molsture Movernent Of Single Water Storage Pit

Agricultural water is the main user and the ratio to the national water is about 73%,but its waste is very severe. The research of saving water has already been proceeded to release the supply and demand contradiction of water resource all over the world. Orchard irrigation technology has also been developed recently. However, the research report about irrigation in single pit has hardly been met. The saving irrigation about water storage in single pit is dug on the surface of the fruit tree canopy projection outer diameter .The objectives of this study are to establish the suitable mathematics model about homogeneous and non-homogeneous soil, to analyze the results of experiments and calculation and to master the soil moisture movement mechanism of the water storage pit irrigation method in order to establish the theory base for suitable technical design schemes of orchards water saving-irrigation.The main contents of this paper are the following:l.The infiltration and soil moisture movement experiment system for the single homogeneous and non-homogeneous soil water storage pit was set up, which can easily measure the wetting front advance and the soil water-content with the suction pressure metro on time. The practice approve this devices are valuable to research the problem of soil water storage irrigation in single pit.2. Establishing the mathematics models of homogeneous and non-homogeneous soil water storage pit irrigation , which were discreted with the Alternating Direction Implicit method and were calculated with numeral method. The results of experiments and calculations are basically in accordance, which indicate that the calculation is applicable. The main conclusions are:1. The main trend of the homogeneous and non-homogeneous soil water infiltration fit well, the shape of wetted soil mass is ellipsoid.2. The factors affecting the infiltration of the soil water are the pit depth, pit radius and the irrigation water quota.3. The Alternating Direction Implicit method (ADI method)is practical for studying the problem of the soil water movement in single pit.