Study on water movement under trickle Irrigation
Liu Xiaoying(The Central Experimental Station on Irrigation of Hebei Province) Yang Zhengang Wang Tianzun(Hebei Agricultural University)
Based on the condition of trickle irrigation, a plane flow model is developed. The model is solved by combining ADI difference procedure with Newton-Raphson method. A FORTRAN program is presented. Experiments are conducted in the laboratory, and calculations are also made. The results indicate that discharge rates have remarkable effect on soil water movement, an increase in trickle discharge rate results in an increase of the ponded area around the nozzle, consequently an increase of the horizontal wetted area and a decrease of the soil wetted depth. It is also found that the maximum value of the wetting front in both horizontal and vertical directions is linearly related to the square root of the infiltration time. The shape of the wetting front at any infiltration time can be expressed by semielliptical equation.