The Small Flow Underground Drip Wet Body Change Rule And The Northwestern Region Of Applied Research

The small flow rate under the condition of drip irrigation soil infiltration moist bodychange rule is the important parameters in the design of underground drip irrigationfor the application of drip irrigation technology in irrigation and water conservancyconstruction and management is of great realistic significance. In this article, throughindoor single point source water diffusion and confirming the moisture diffusionexperiment, got in different head flow, irrigation water, drops the head spacing andother factors in the underground drip irrigation of point source infiltration under theconditions of the shape of the moist soil body, the wetting front movement situation,the change laws of soil moisture content, etc. The conclusion as follows:1) single point source underground drip irrigation water infiltration process,increase with the gradually drop head flow, wetting front in the horizontal direction andvertical direction of the migration distance also showed a trend of growth, but in ahorizontal direction of migration distance growth faster than the growth rate of verticalmigration distance.2) in the same wet area, the vertical downward part of the soil moisture contentcompared with horizontal soil moisture content, the vertical position of the minimal soilmoisture content, soil moist as wetting front spread outward, in boundary of moisturecontent in gradually decline.3) confirming the water infiltration process is divided into two stages: the firststage for free infiltration stage, the wet body shape won’t appear convergencephenomenon; Phase, the second phase of intersection infiltration between each drophead surrounding soils at this time there will be a wet body blend, volume change wetbody silhouette; At the interface between intersection wetting front in the direction ofthe vertical downward migration distance is greater than the vertical upward directionof migration distance; At the interface between convergence wet body diffusionvelocity and flow rate is less, mainly depends on the size of the irrigation water.4) in the distance between head and irrigation water drops under the sameconditions, the wet body intersection depending on head flow, flow rate, the greaterthe time between the sooner. Convergence phenomenon happens, in the intersectionarea of wet body shape is obvious changes, but the parts of the soil moisture content is almost unchanged, so for a dense spacing type crops such as cotton, corn, but atthe same time of increasing drop head flow by controlling irrigation water to raise thewater required for crop growth, to improve the yield of crops.